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Characterization Of Linear Type Traits In Nili Rivei Buffaloes Of Pakistan

By: Riaz Hussain Mirza | Prof. Dr. Khalid Javed.
Contributor(s): Prof. Dr. Muhammad Abdullah.
Material type: materialTypeLabelBookPublisher: 2013Subject(s): Department of Livestock Production | Phd. thesisDDC classification: 1708,T Dissertation note: The present study on conformation recording of Nili Ravi buffaloes was planned because there was lack of studies on this aspect of Nili Ravi buffaloes. The main objective of the study was to document and characterize linear type traits in Nili Ravi buffaloes so that the buffaloes with proper body characteristics could be identified for selection and breeding programs. Nili Ravi buffalo herds maintained at Livestock Experiment Station Bhunikey, Pattoki, distt. Kasur, Livestock Experiment Station, Chack Katora distt. Bahawalpur, Livestock Experiment Station Haroonabad distt. Bahawalnagar, Livestock Experiment Station Khushab, distt. Khushab, Livestock Experiment Station Rakh Ghulaman distt. Bhakhar and some private breeders were utilized in this study. The guidelines for conformational recording of dairy cattle provided by the International Committee for Animal Recording (ICAR) were followed in this study. A total of 437 milking buffaloes were scored for linear type traits on a scale of 1-9. First scoring was performed within 15 to 90 days of calving and then each after about 90 days interval. Genetic parameters viz. heritabilities, phenotypic and genetic correlations were estimated using Best Linear Unbiased Prediction (BLUP) evaluation techniques. Influencing factors such as age of the buffalo at scoring, stage of lactation, parity, herd and season of scoring were included in the model. Individual Animal Model was fitted under Restricted Maximum Likelihood (REML) Procedure. Data were analysed using the mixed model procedure of the Statistical Analysis Systems. Genetic parameters were estimated fitting an Individual Animal Model using the ASREML set of computer programs. A total of 1180 records on different linear type traits and body measurements were generated over a scoring period of 2 years. Most of the average values for linear type traits were seen to fall under the intermediate category of 4-6. The means±SD for different linear type traits were found as 5.07±1.35, 5.23±2.35, 5.41±1.45, 5.76±0.98, 6.73±1.53, 4.91±1.85, 4.99±0.88, 4.99±0.90, 5.39±2.13, 4.78±1.1, 5.36±1.56, 4.91±1.84, 5.76±1.67, 3.58±0.88, 5.66±2.24, 6.42±0.88, 4.88±0.69, 4.92±1.08, 4.87±0.84, 5.34±1.79, 4.76±1.78, 5.97±0.94, 5.04±2.488, 5.15±1.65 and 6.44±1.03 for stature, chest width, body depth, angularity, rump angle, rump width, rear legs set, rear legs rear view, foot angle , fore udder attachment, rear udder height, central ligament, udder depth, front teat placement, teat length, rear teat placement, locomotion, body condition score, top line, bone structure, rear udder width, udder balance, teat thickness, thurl width, and temperament, respectively. A highly significant effect of herd was observed on all of the linear type traits (P< 0.0001). Effect of stage of lactation was found to be highly significant for udder conformation related traits. Parity was observed as a highly significant source of variation for some of the body traits including stature, body depth, body condition score and bone structure. However most of the udder related traits were affected by this factor. A non significant effect of parity was observed on chest width, angularity, rump angle, rump width, central ligament, locomotion, top line, udder balance, thurl width and temperament. A highly significant effect of season of scoring was observed on chest width, angularity, rump angle, rear legs set, rear legs rear view, locomotion and thurl width among body traits. However, stature, body depth, body condition score, top line, bone structure and temperament were not affected by season of scoring. Udder conformation traits including fore udder attachment, rear udder height, central ligament, rear udder width, and udder balance were affected by the season of scoring, however rest of the udder traits including udder depth, front teat placement, teat length, rear teat placement and teat thickness were not significantly different in different seasons. Significant linear effect of age of the buffalo at scoring was seen on most of the linear type traits. including stature, body depth, rear legs set, rear legs rear view, foot angle, fore udder attachment, rear udder height, central ligament, udder depth, teat length, body condition score, bone structure, rear udder width, teat thickness and thurl width. However, chest width, angularity, rump angle, rump width, front teat placement, rear teat placement, locomotion, top line, udder balance and temperament were not affected by linear effect of age. Quadratic effect of age was found as significant on most of the linear type traits except chest width, angularity, rump width, front teat placement, rear teat placement, locomotion, udder balance and temperament. Univariate heritability estimates of linear type traits were observed as for stature, 0.36±0.092; chest width, 0.10±0.081; body depth, 0.32±0.081; angularity, 0.06±0.071; rump angle, 0.15±0.071; rump width, 0.38±0.092; rear legs set, 0.02±0.07; rear legs rear view, 0.08±0.07; foot angle, 0.09±0.07; fore udder attachment, 0.21±0.07; rear udder height, 0.09±0.07; central ligament, 0.09±0.09; udder depth, 0.10±0.091; front teat placement, 0.11±0.091; teat length, 0.08±0.091; rear teat placement, 0.11±0.081; locomotion, 0.06±0.06; body condition score, 0.14±0.091; top line, 0.03±0.05; bone structure, 0.09±0.09; rear udder width, 0.15±0.09; udder balance, 0.16±0.07; teat thickness, 0.22±0.091; thurl width, 0.31±0.09 and temperament, 0.14±0.07, respectively. Some important positive phenotypic correlations of linear type traits with 305 days milk yield were observed as 0.18±0.04 for body depth, 0.15±0.04 for rump angle, 0.13±0.04 for rump width, 0.30±0.04 for rear udder height, 0.43±0.03 for central ligament, 0.16±0.03 for rear teat placement and 0.19±0.04 for rear udder width. Rest of the phenotypic correlations were very low. Considerable negative phenotypic correlations included -0.16±035 for body condition score, -0.15±0.04 for top line, -0.16±0.03 for front teat placement, -0.14±0.04 for udder depth and -0.26±0.04 for fore udder attachment. Most of the linear type traits showed positive but low genetic correlation with 305 days milk yield including 0.140±0.0001 with stature, 0.210±0.0001 with body depth, 0.11±0.0001 with rump angle, 0.19±0.0002 with rump width, 0.14±0.0001 with rear udder height, 0.20±0.000001 with central ligament, 0.14±0.0000001 with rear teat placement, 0.13±0.0001 with rear udder width, 0.14±0.0000001 with udder balance, 0.09±0.0001 with thurl width and 0.12±0.0000001 with temperament. Phenotypic and genetic correlations of most the linear type traits with score day milk yield were generally higher than with 305 days milk yield. Phenotypic correlations with score day milk yield were observed as 0.09±0.03 for stature, -0.21±0.03 for chest width, -0.05±0.04 for body depth, -0.17±0.03 for angularity, -0.12±0.03 for rump angle, -0.16±0.05 for rump width, -0.32±0.03 for rear legs set, -0.16±0.04 for rear legs rear view, -0.22±0.03 for foot angle, -0.34±0.03 for fore udder attachment, -0.16±0.04 for rear udder height, -0.16±0.04 for central ligament, -0.25±0.03 for udder depth, 0.06±0.04 for front teat placement, 0.008±0.03 for teat length, -0.19±0.04 for rear teat placement, -0.15±0.04 for locomotion, -0.22±0.03 for body condition score, -0.35±0.03 for top line, -0.08±0.04 for bone structure, -0.17±0.05 for rear udder width, -0.18±0.04 for udder balance, -0.20±0.03 for teat thickness, -0.11±0.04 for thurl width and -0.11±0.05 for temperament, respectively. Genetic correlations with score day milk yield were observed as 0.57±0.05 for stature, 0.09±0.02 for chest width, 0.31±0.04 for body depth, 0.06±0.02 for angularity, 0.15±0.03 for rump angle, 0.30±0.05 for rump width, 0.04±0.02 for rear legs set, 0.06±0.01 for rear legs rear view, 0.06±0.02 for foot angle, 0.10±0.02 for fore udder attachment, 0.18±0.03 for rear udder height, 0.12±0.02 for central ligament, 0.18±0.02 for udder depth, 0.60±0.06 for front teat placement, 0.23±0.03 for teat length, 0.07±0.01 for rear teat placement, 0.021±0.02 for locomotion, 0.12±0.02 for body condition score, 0.08±0.02 for top line, 0.08±0.03 for bone structure, 0.19±0.04 for rear udder width, 0.19±0.03 for udder balance, 0.095±0.02 for teat thickness, 0.12±0.02 for thurl width and 0.27±0.05 for temperament, respectively. Among body measurements, head related measurements included head length, horn diameter at base, length and width of ear and poll width and their average values were found as 54.13±3.48, 18.65±2.06, 29.5±2.12 and 18.66±1.22, and 30.95±2.35 cm, respectively. Average values for neck length and neck circumference were observed as 53.32±4.56 and 95.77±8.58 cm, respectively. The height and length of body was measured at different body points and average values were found as 139.56±6.29 cm for horizontal body length, 154.01±7.61 cm for diagonal body length, 135.77±4.4 cm for height at sacrum, 132.04±4.57 cm for height at withers, 130.77±4.61 cm for height at 6th rib position, 126.34±4.51 cm for height at last rib position, 128.89±4.83 cm for height at hook bone and 118.81±4.45 cm for height at pin bone. The average values for heart girth, paunch girth, sprung at 6th rib position and sprung at last rib position were resulted as 194.46±10.31, 238.52±13.96, 45.15±4.48 and 68.72±5.2 cm, respectively. Mean estimates for top wedge area, front wedge area and side wedge area were obtained as 3152.79±309.53, 1030.17±136.34 and 3105.07±345.26 cm2, respectively. The length of tail and its diameter at base was measured and its value averaged 103.51±12.55 and 22.41±2.005 cm, respectively. Average values of skin thickness at neck, ribs, belly and tail region were found as 4.16±1.16, 5.85±1.36, 7.34±1.49 and 1.71±0.55 mm, respectively. Mean values for some other traits included 43.52±2.582 cm for rump length, 3.12±0.56 cm for heel depth and 523.13±81.63 kg for body weight. It was observed that herd was a significant source of variation for all body measurement traits. Age of the buffalo at classification was a significant source of variation for all of the body measurements except horn diameter at base, poll width, tail length, skin thickness at tail and height at hook bone. Most of the body measurements have been found to be lowly to moderately heritable in the current study. Heritability estimates for various body measurements were observed as 0.16±0.09 for horn diameter at base, 0.38±0.04 for ear length, 0.06±0.09 for ear width, 0.25±0.091 for head length, 0.14±0.09 for poll width, 0.03±0.06 for neck circumference, 0.05±0.07 for neck length, 0.05±0.09 for body length, 0.05±0.09 for diagonal body length, 0.41±0.09 for tail length, 0.28±0.091 for tail diameter at base, 0.04±0.09 for skin thickness at neck, 0.02±0.09 for skin thickness at ribs, 0.10±0.09 for skin thickness at belly, 0.07±0.08 for skin thickness at tail, 0.11±0.09 for height at sacrum, 0.28±0.09 for height at withers, 0.22±0.092 for height at 6th rib position, 0.25±0.092 for height at last rib position, 0.18±0.091 for height at hook bone, 0.07±0.08 for height at pin bone, 0.04±0.06 for sprung at 6th rib position, 0.07±0.06 for sprung at last rib position, 0.13±0.09 for heart girth, 0.05±0.09 for paunch girth, 0.11±0.09 for top wedge area, 0.05±0.06 for front wedge area, 0.16±0.07 for side wedge area, 0.13±0.08 for rump length, 0.02±0.06 for heel depth and 0.33±0.07 for body weight. Phenotypic correlations of 305 days milk yield with various body measurements were in low range. Positive phenotypic correlations ranged from 0.02±0.04 for sprung at 6th rib position to 0.17±0.05 for ear length. Some of the important body measurements have positive phenotypic correlation with 305 days milk yield as 0.15±0.04 for head length, 0.04±0.04 for diagonal body length, 0.04±0.02 for height at withers, 0.11±0.03 for height at sacrum, 0.11±0.04 for sprung at last rib position, 0.04±0.04 for heart girth, 0.08±0.03 for rump length and 0.07±0.03 for body weight. Negative phenotypic correlations with 305 days milk yield ranged from -0.03±0.03 for side wedge area to -0.25±0.03 for horn diameter at base. Some important negative phenotypic correlations included -0.25±0.03 for horn diameter at base, -0.04±0.04 for neck circumference, -0.12±0.03 for skin thickness at neck and -0.08±0.03 for front wedge area. Positive phenotypic correlation with score day milk yield included 0.09±0.05 for body weight, 0.07±0.002 for rump length, 0.09±0.003 for sprung at last rib position, 0.09±0.005 for height at hook bone, 0.08±0.02 for height at sacrum. Rest of all the traits were low in correlation with milk yield. Negative phenotypic correlation with score day milk yield included horn diameter at base as -0.15±0.02 and heel depth as -0.13±0.04. Rest of all negative phenotypic correlations were very low. Positive genetic correlations of 305 days milk yield varied from 0.02±0.002 for ear width to 0.23±0.02 for side wedge area. Some important body measurements have positive genetic correlation values as 0.121±0.000001 for head length, 0.162±0.000001 for diagonal body length, 0.080±0.000001 for height at withers, 0.15±0.000001 for height at sacrum, 0.15±0.000001 for sprung at last rib position, 0.14±0.0005 for heart girth and 0.16±0.007 for body weight. Negative genetic correlation for this trait was observed only for skin thickness at neck region as -0.16±0001. About 40 traits regarding udder and teat measurements before and after milking were analysed. Average values for udder length, width, height, depth and circumference before milking were found as 52.65±6.87, 53.52±6.19, 54.34±4.99, 18.76±3.87, and 77.05±11.69 cm, respectively while the corresponding values for the same traits after milking were found as 47.08±6.57, 48.15±5.79, 55.39±5.15, 18.11±4.11 and 67.04±8.11 cm, respectively. Teat impression distances between front teats, rear teats, fore and rear teats from right side and fore and rear teats from left side were found as 12.46±3.01, 7.01±1.91, 8.08±1.8 and 7.71±1.75 cm, respectively. Pre stimulation and after milking teat characteristics were found as 12.93±3.12 and 11.71±2.83 cm for distance between front teats; 7.48±1.93 and 6.61±1.58 cm for distance between hind teats; 8.34±1.91 and 7.54±1.60 cm for distance between fore and hind teats of right side; 8.004±1.95 and 7.17±1.60 cm for distance between fore and hind teats of left side; 10.19±2.17 and 9.057±1.50 for diameter of fore right teat; 10.92±2.45 and 9.611±1.66 cm for diameter of rear right teat; 10.33±2.11 and 9.33±1.45 cm for diameter of fore left teat; 11.25±2.54 and 9.937±1.76 cm for diameter of rear left teat; 10.71±2.63 and 11.2±2.39 cm, for teat length of fore right teat; 13.05±3.27 and 13.13±3.03 for teat length of rear right teat; 11.09±2.71 and 11.88±2.61 cm for teat length fore left teat and 13.75±3.04 and 14.47±2.99 for teat length of rear left teat, respectively. All of the udder conformation traits before and after milking were highly significantly different in different herds (P<0.0001). Stage of lactation was found to be highly significant source of variation (P<0.0001) for before milking udder length, before milking udder height, average before milking udder circumference, after milking udder length, after milking average udder circumference, teat impression distance between fore, between rear and between fore and rear teats on both sides. However, before milking average udder width, before milking udder depth, after milking average udder width, after milking udder height and after milking udder depth were not affected by this factor. All of the above mentioned traits were significantly affected by parity except after milking udder depth and teat impression distance between fore teats and between rear teats. Season of scoring significantly affected before milking udder length (P<0.01), before milking average udder width (P<0.05), before milking average udder circumference (P<0.01), after milking average udder width (P<0.01), after milking average udder circumference (P<0.0001), teat impression distance between fore and hind teats of left side (P<0.05). Rest of all the traits were not significantly different in different seasons. Most of the udder traits were significantly affected by linear and quadratic effect of age of the buffalo at classification. Herd was a significant source of variation for all teat related traits recorded at pre stimulation before milking time. Stage of lactation significantly affected pre stimulation distance between front teats, pre stimulation distance between hind teats, pre stimulation distance between fore and hind teats on right and left side, pre stimulation diameter of fore right teat, pre stimulation teat length of fore right teat, pre stimulation teat length of rear right teat, pre stimulation teat length of fore left and rear left teat. However, pre stimulation diameter of rear right teat, pre stimulation diameter of fore left teat and pre stimulation diameter of rear left teat were not affected by this factor. All of these parameters were affected by parity except pre stimulation distance between hind teats and pre stimulation teat length of fore left teat. Similarly all of these traits were affected by season of scoring except pre stimulation distance between fore, between hind, between right and between left teats. All of teat characteristics after milking were significantly affected by herd. Stage of lactation significantly affected after milking distance between fore and hind teats of right side (P<0.05), after milking teat length of fore right and rear right teat (P<0.01), after milking teat length of fore left teat (P<0.05) and rear left teat (P<0.0001). Rest of all traits after milking were not affected by stage of lactation. Most of the teat parameters after milking were significantly affected by parity except after milking distance between front and between rear teats, after milking teat length of rear right teat and after milking teat length of fore left teat. Distances among teats after milking and after milking diameter of rear left teat were not significantly affected by season. Rest of all traits were significantly affected by this factor. Heritability estimates for before milking udder length, average udder width, udder height, udder depth and average udder circumference were found as 0.08±0.07, 0.22±0.08, 0.22±0.09, 0.05±0.06 and 0.21±0.07, respectively. The corresponding values after milking for these traits were observed as 0.14±0.07, 0.20±0.08, 0.09±0.08, 0.02±0.08 and 0.09±0.07, respectively. Heritability estimates for before milking and after milking teat characteristics were found as 0.11±0.09 and 0.15±0.09 for distance between front teats; 0.03±0.06 and 0.03±0.07 for distance between hind teats; 0.32±0.09 and 0.06±0.07 for distance between fore and hind teats of right side; 0.16±0.08 and 00.09±0.07 for distance between fore and hind teats of left side; 0.21±0.08 and 0.11±0.08 for diameter of fore right teat; 0.05±0.05 and 0.02±0.05 for diameter of rear right teat; 0.19±0.08 and 0.25±0.09 for diameter of fore left teat; 0.07±0.06 and 0.03±0.07 for diameter of rear left teat; 0.12±0.06 and 0.08±0.06 for teat length of fore right teat; 0.02±0.05 and 0.11±0.07 for teat length of rear right teat; 0.29±0.09 and 0.29±0.092 for teat length of fore left teat and 0.14±0.08 and 0.08±0.07 for teat length of rear left teat, respectively. Phenotypic correlations of before and after milking udder length, average udder width, udder height, udder depth and average udder circumference with 305 days milk yield were found as 0.29±0.04 and 0.18±0.04; 0.30±0.04 and 0.33±0.04; -0.26±0.03 and -0.20±0.03; 0.07±0.04 and 0.06±0.05 and 0.18±0.04 and 0.14±0.04, respectively. Corresponding values in the same order for genetic correlations were observed as 0.17±0.0002 and 0.21±0.0003; 0.33±0.0002 and 0.19±0.0003; -0.29±0003 and -0.34±0003; 0.10±0.0001 and 0.07±0.0001 and 0.28±0.0004 and 0.23±0.0003, respectively. Phenotypic correlations of before and after milking udder length, average udder width, udder height, udder depth and average udder circumference with score day milk yield were found as 0.29±0.03 and -0.18±0.02; -0.32±0.02 and 0.17±0.01, -0.38±0.001 and -0.20±0.002, 0.28±0.01 and -0.04±0.04 and 0.21±0.04 and -0.15±0.04, respectively. Phenotypic correlations for pre stimulation and after milking teat characteristics with 305 days milk yield were found as 0.19±0.03 and 0.07±0.03 for distance between front teats; 0.20±0.04 and 0.20±0.04 for distance between hind teats; 0.21±0.03 and 0.21±0.03 for distance between fore and hind teats of right side; 0.18±0.03 and 0.18±0.03 for distance between fore and hind teats of left side; 0.07±0.03 and 0.27±0.04 for diameter of fore right teat; -0.04±0.03 and 0.14±0.04 for diameter of rear right teat; -0.03±0.04 and 0.20±0.04 for diameter of fore left teat; -0.02±0.04 and 0.20±0.03 for diameter of rear left teat; 0.24±0.03 and 0.28±0.03, for teat length of fore right teat; -0.13±0.03 and -0.009±0.04 for teat length of rear right teat; 0.01±0.02 and 0.12±0.03 for teat length fore left teat and 0.06±0.03 and 0.22±0.03 for teat length of rear left teat, respectively. Genetic correlations for pre stimulation and after milking teat characteristics with 305 days milk yield were found as 0.22±0.0002 and 0.12±0.0003 for distance between front teats; 0.26±0.0001 and 0.13±0.0001 for distance between hind teats; 0.11±0.0001 and 0.09±0.0001 for distance between fore and hind teats of right side; 0.10±0.0001 and 0.07±0.0001 for distance between fore and hind teats of left side; 0.11±0.0001 and 0.11±0.0001 for diameter of fore right teat; 0.09±0.0002 and 0.16±0.0001 for diameter of rear right teat; 0.001±0.000001 and 0.001±0.0001 for diameter of fore left teat; 0.001±0.000001 and 0.001±0.0001 for diameter of rear left teat; 0.080±0.00001 and 0.11±0.0001 for teat length of fore right teat; 0.07±0.000001 and 0.001±0.0002 for teat length of rear right teat; 0.003±0.000001 and 0.003±0.0003 for teat length fore left teat and 0.003±0.000001 and 0.002±0.0002 for teat length of rear left teat, respectively. Phenotypic correlations for pre stimulation and after milking teat characteristics with score day milk yield were found as -0.37±0.02 and -0.48±0.03 for distance between front teats; 0.04±0.04 and 0.06±0.04 for distance between hind teats; 0.04±0.04 and 0.03±0.04 for distance between fore and hind teats of right side; 0.03±0.039 and 0.08±0.04 for distance between fore and hind teats of left side; -0.33±0.03 and -0.16±0.04 for diameter of fore right teat; -0.46±0.03 and -0.26±0.04 for diameter of rear right teat; -0.41±0.03 and -0.24±0.04 for diameter of fore left teat; -0.30±0.03 and -0.28±0.04 for diameter of rear left teat; -0.43±0.03 and -0.49±0.03 for teat length of fore right teat; -0.36±0.02 and -0.47±0.02 for teat length of rear right teat; -0.41±0.034 and -0.43±0.03 for teat length fore left teat and -0.28±0.021 and -0.53±0.02 for teat length of rear left teat, respectively. Genetic correlations for before and after milking teat characteristics with score day milk yield were found as 0.13±0.016 and 0.15±0.02 for distance between front teats; 0.30±0.04 and 0.40±0.05 for distance between hind teats; 0.19±0.05 and 0.38±0.05 for distance between fore and hind teats of right side; 0.32±0.06 and 0.44±0.06 for distance between fore and hind teats of left side; 0.22±0.03 and 0.27±0.04 for diameter of fore right teat; 0.16±0.02 and 0.23±0.03 for diameter of rear right teat; 0.15±0.02 and 0.22±0.03 for diameter of fore left teat; 0.11±0.02 and 0.24±0.03 for diameter of rear left teat; 0.19±0.02 and 0.17±0.02 for teat length of fore right teat; 0.075±0.01 and 0.07±0.01 for teat length of rear right teat; 0.27±0.029 and 0.27±0.03 for teat length of fore left teat and 0.10±0.01 and 0.08±0.01 for teat length of rear left teat, respectively. Least squares means for various performance traits were found as 7.02±2.46 for score day milk yield, 1801.61±624.59 for lactation milk yield, 2074.1±360.85 for 305 days milk yield, 2149.09±680.59 for best milk yield, 272±69 for lactation length, 408.553±203.63 for preceeding dry period, 1762.05±305.97 for age at first calving, 477.68±64.53 for weight at first calving, 110±33 for age at scoring in months, 523.133±81.63 for weight at scoring in Kg. Most of the phenotypic studies on Nili Ravi breed are limited to recording only few body measurements. In order to explore the physical features of this breed, linear scoring system needs to be adopted which is based on measurement of certain specific parts of body as per international standards according to the ICAR guidelines. However, some of the linear scores developed for dairy cattle breeds do not fit for this breed and harmonization of certain trait definitions is needed even for the linear score system for this breed. The following points are important regarding linear scoring system for Nili Ravi buffaloes: " In case of rump angle, the score ranging as 1-3 which refers to higher pin bone than hook bone is not present in Nili Ravi buffaloes. The score for central ligament ranging as 1-3 which refers to convex floor of udder has not been observed in this breed. The position of front teat placement as inside of quarter scoring as 7-9 has not been observed in Nili Ravi buffaloes. The position of rear teat placement as outside of quarter scoring as 1-3 has not been observed in Nili Ravi buffaloes. The score for top line ranging as 8-9 which represents a back bent upwards has not been observed in this breed. The score of 1 and 2 which represents a rear udder deeper than the fore udder has also not been observed in the present study. A higher temperament score indicates that buffaloes tend to be excited especially at the time of milking and handling. This behaviour of buffaloes needs to be improved through selection and breeding. " A highly significant effect of herd was observed on all of the linear type traits. Effect of stage of lactation was found to be highly significant for udder conformation related traits including fore udder attachment, rear udder height, central ligament, udder depth, teat length and rear udder width. Most of the udder related traits were affected by parity such as fore udder attachment, rear udder height, udder depth, teat length, rear udder width and teat thickness. significant effect of parity was observed on chest width, angularity, rump angle, rump width, top line, thurl width, and temperament. " Initiation of conformation recording in public and private sector and use of selective and planned breeding will be helpful for the improvement in milk yield and to bring uniformity in body features of Nili Ravi buffaloes. " Scoring in first parity should be adopted as in later parities adjustment for age and parity will be needed. " Differences among herds for most of the traits suggest that performance can be improved by exploiting genetic potential through selection and breeding. Heritability estimates for most of the linear type traits were found as higher than the reported values available in literature. The reasons might be due to species differences and relatively small data set as well as incomplete pedigree records. Even then the results might be considered for inclusion of some of the linear type traits in selection programs. Keeping in view that this is a preliminary study on genetic aspects of linear type traits in Nili Ravi buffaloes, further studies and research with larger data set is needed to explore linear type traits and to validate the findings of the current study. " A positive genetic correlation of stature with milk yield suggest that taller and heavier buffaloes produced more milk and selection for taller buffaloes may result in improved milk yield but the efficiency of milk yield must be studied before making indirect selection for milk yield through stature. Negative phenotypic correlation of chest width with score day milk yield suggested that buffaloes with wider chest are relatively less efficient in milk production. Further studies are needed with larger data set to verify the results. A considerable positive genetic correlation between body depth and milk yield suggest that body depth may be considered for indirect selection of higher milk yield in Nili Ravi buffaloes. Considerable genetic correlation with milk yield suggest that rump width is important in this breed of buffaloes and can be used for indirect selection for improved milk yield. A considerable negative phenotypic correlation of fore udder attachment with milk yield is important however negligible genetic correlation suggest that fore udder attachment is independent of milk producing genes and separate selection for each trait should be considered keeping in view heritability of the trait in Nili Ravi buffaloes. A positive genetic correlation of rear udder height with milk yield suggested that selection for this trait might be helpful for improved milk yield in Nili Ravi buffaloes. Genetic correlation of teat length with score day milk yield is considerable in the current study but very low with 305 days milk yield. The findings of current study suggested that rear teat placemen has a considerable genetic correlation with milk yield and can be used for indirect selection for better milk yield. The results of current study are not in agreement with most of the reports in the literature regarding correlation of BCS with milk yield. Further research is needed to verify positive genetic correlation of BCS with milk yield before using BCS as selection criterion for milk yield in Nili Ravi buffaloes. Due to negative phenotypic correlation of body condition score with milk yield, an optimal score of below average ranging from 4 to 5 may be recommended. A positive genetic correlation of rear udder width with milk yield suggested that some of the same genes are controlling milk yield and rear udder width and indirect selection for improved milk yield is possible through selection for rear udder width in Nili Ravi buffaloes. This genetic correlation with milk yield is considerable but further studies are needed before the udder balance could be included for selection program in Nili Ravi buffaloes. " Current study indicated that teat thickness is not genetically important with negligible correlation with milk yield in Nili Ravi buffaloes but negative phenotypic correlation is considerable and buffaloes with thinner teats are suitable for more milk production. A low but positive genetic correlation of thurl width with milk yield provides a scope for further studies to explore this trait in Nili Ravi buffaloes. Further studies are needed with relatively larger data set to explore temperament and verify its relationship with milk yield in this breed of buffaloes. Generally, the least squares means for most of the body measurements were found in the normal range and were in agreement with most of the reports in literature. " Comparatively higher body weight was observed than the reports available for Nili Ravi buffaloes. One of the reason for this might be relatively better supply of feed and fodder during the course of study and also the records pertaining to 3rd and latter parities were more in number than the records on younger buffaloes. The top and side wedge area are almost similar with less variation showing that Nili Ravi buffaloes are relatively more wedge shaped. " Most of the body measurements were affected by the herd and age factors but the effect of parity, stage of lactation and season of scoring was variable for different traits and showed not very clear trend. Body weight was affected by all the factors studied in the current investigation. Most of the body measurements have been found to be moderately to highly heritable in the current study. Overall range of heritability estimates for body measurements was found as 0.08±0.09 to 0.92±0.00. " Skin thickness has been found under the genetic control and can be improved through selection and breeding keeping in view its importance and demand in the leather industry and also its correlation with milk yield. " Diagonal body length in the current study has shown a low but positive genetic correlation with milk yield and this trait might be considered in the selection program for Nili Ravi buffaloes. The negative genetic correlation of skin thickness in the neck region with 305 days milk yield is important and advocates the thinking of farmers about the negative correlation of skin thickness with milk yield. Genetic correlation of heart girth with milk yield although not very high but seems to be important and can be considered for indirect selection for milk yield through heart girth measurement. A reasonable genetic correlation of body weight with milk yield suggested that this trait should be considered in the selection program for improved milk yield in Nili Ravi buffaloes. " Udder colour has not been found important. Buffaloes with pendulous udders have produced more milk. The possible reason for this more milk is that such buffaloes were recorded in latter parities and age of those buffaloes was high and the size of their udder was large. The frequency of buffaloes with such type of udder is only 8%. Buffaloes with such type of pendulous udders are more prone to udder and teat injuries and mastitis and their life time production is less. Thick and lengthy teats have been observed in this breed and the reason might be due to hand milking and direct suckling of cows by the calves. " Most of the udder traits were significantly affected by herd, parity, stage of lactation and age of the buffaloes at classification. Most of the udder measurements have been found highly heritable and this provides a good scope for improvement of these traits through selection and breeding. A general decrease in the distance between fore, rear and fore and rear teats on both sides was observed after milking. This indicated that the distance measured after milking was a good indicator of actual distance between teats of this breed irrespective of stage of lactation. Udder length, width, udder circumference and height either recorded before milking or after milking have been found genetically correlated with milk yield and they should be considered for selection decisions in Nili Ravi buffaloes. A reasonable positive genetic correlation of distance between fore and between rear teats suggested that this distance is important for milk yield and should be considered for selection in Nili Ravi buffaloes. The results of present study suggest that teat diameter is not genetically much important for milk yield and the reason of thick teats is due to hand milking and direct suckling by the calves. " Teat distance between front teat, between rear teat, diameter of fore right and rear right teat and teat length of fore right teat have shown low but not negligible genetic correlations with milk yield and should be given some importance in making selection decisions in Nili Ravi buffaloes. " Brown colour buffaloes have not been observed in this study because such animals at Govt. livestock farms are culled at an early age, however farmers think that such type of buffaloes are better milk yielder and they like and demand such animals, development and conservation of these animals is advocated at experimental level to study their potential. " Further research is needed to evaluate visual image analysis system as a tool for quick and more accurate conformation recording.
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The present study on conformation recording of Nili Ravi buffaloes was planned because there was lack of studies on this aspect of Nili Ravi buffaloes. The main objective of the study was to document and characterize linear type traits in Nili Ravi buffaloes so that the buffaloes with proper body characteristics could be identified for selection and breeding programs. Nili Ravi buffalo herds maintained at Livestock Experiment Station Bhunikey, Pattoki, distt. Kasur, Livestock Experiment Station, Chack Katora distt. Bahawalpur, Livestock Experiment Station Haroonabad distt. Bahawalnagar, Livestock Experiment Station Khushab, distt. Khushab, Livestock Experiment Station Rakh Ghulaman distt. Bhakhar and some private breeders were utilized in this study.
The guidelines for conformational recording of dairy cattle provided by the International Committee for Animal Recording (ICAR) were followed in this study. A total of 437 milking buffaloes were scored for linear type traits on a scale of 1-9. First scoring was performed within 15 to 90 days of calving and then each after about 90 days interval.
Genetic parameters viz. heritabilities, phenotypic and genetic correlations were estimated using Best Linear Unbiased Prediction (BLUP) evaluation techniques. Influencing factors such as age of the buffalo at scoring, stage of lactation, parity, herd and season of scoring were included in the model. Individual Animal Model was fitted under Restricted Maximum Likelihood (REML) Procedure. Data were analysed using the mixed model procedure of the Statistical Analysis Systems. Genetic parameters were estimated fitting an Individual Animal Model using the ASREML set of computer programs.
A total of 1180 records on different linear type traits and body measurements were generated over a scoring period of 2 years. Most of the average values for linear type traits were seen to fall under the intermediate category of 4-6. The means±SD for different linear type traits were found as 5.07±1.35, 5.23±2.35, 5.41±1.45, 5.76±0.98, 6.73±1.53, 4.91±1.85, 4.99±0.88, 4.99±0.90, 5.39±2.13, 4.78±1.1, 5.36±1.56, 4.91±1.84, 5.76±1.67, 3.58±0.88, 5.66±2.24, 6.42±0.88, 4.88±0.69, 4.92±1.08, 4.87±0.84, 5.34±1.79, 4.76±1.78, 5.97±0.94, 5.04±2.488, 5.15±1.65 and 6.44±1.03 for stature, chest width, body depth, angularity, rump angle, rump width, rear legs set, rear legs rear view, foot angle , fore udder attachment, rear udder height, central ligament, udder depth, front teat placement, teat length, rear teat placement, locomotion, body condition score, top line, bone structure, rear udder width, udder balance, teat thickness, thurl width, and temperament, respectively.
A highly significant effect of herd was observed on all of the linear type traits (P< 0.0001). Effect of stage of lactation was found to be highly significant for udder conformation related traits. Parity was observed as a highly significant source of variation for some of the body traits including stature, body depth, body condition score and bone structure. However most of the udder related traits were affected by this factor. A non significant effect of parity was observed on chest width, angularity, rump angle, rump width, central ligament, locomotion, top line, udder balance, thurl width and temperament. A highly significant effect of season of scoring was observed on chest width, angularity, rump angle, rear legs set, rear legs rear view, locomotion and thurl width among body traits. However, stature, body depth, body condition score, top line, bone structure and temperament were not affected by season of scoring. Udder conformation traits including fore udder attachment, rear udder height, central ligament, rear udder width, and udder balance were affected by the season of scoring, however rest of the udder traits including udder depth, front teat placement, teat length, rear teat placement and teat thickness were not significantly different in different seasons.
Significant linear effect of age of the buffalo at scoring was seen on most of the linear type traits. including stature, body depth, rear legs set, rear legs rear view, foot angle, fore udder attachment, rear udder height, central ligament, udder depth, teat length, body condition score, bone structure, rear udder width, teat thickness and thurl width. However, chest width, angularity, rump angle, rump width, front teat placement, rear teat placement, locomotion, top line, udder balance and temperament were not affected by linear effect of age. Quadratic effect of age was found as significant on most of the linear type traits except chest width, angularity, rump width, front teat placement, rear teat placement, locomotion, udder balance and temperament.
Univariate heritability estimates of linear type traits were observed as for stature, 0.36±0.092; chest width, 0.10±0.081; body depth, 0.32±0.081; angularity, 0.06±0.071; rump angle, 0.15±0.071; rump width, 0.38±0.092; rear legs set, 0.02±0.07; rear legs rear view, 0.08±0.07; foot angle, 0.09±0.07; fore udder attachment, 0.21±0.07; rear udder height, 0.09±0.07; central ligament, 0.09±0.09; udder depth, 0.10±0.091; front teat placement, 0.11±0.091; teat length, 0.08±0.091; rear teat placement, 0.11±0.081; locomotion, 0.06±0.06; body condition score, 0.14±0.091; top line, 0.03±0.05; bone structure, 0.09±0.09; rear udder width, 0.15±0.09;
udder balance, 0.16±0.07; teat thickness, 0.22±0.091; thurl width, 0.31±0.09 and temperament, 0.14±0.07, respectively.
Some important positive phenotypic correlations of linear type traits with 305 days milk yield were observed as 0.18±0.04 for body depth, 0.15±0.04 for rump angle, 0.13±0.04 for rump width, 0.30±0.04 for rear udder height, 0.43±0.03 for central ligament, 0.16±0.03 for rear teat placement and 0.19±0.04 for rear udder width. Rest of the phenotypic correlations were very low. Considerable negative phenotypic correlations included -0.16±035 for body condition score, -0.15±0.04 for top line, -0.16±0.03 for front teat placement, -0.14±0.04 for udder depth and -0.26±0.04 for fore udder attachment.
Most of the linear type traits showed positive but low genetic correlation with 305 days milk yield including 0.140±0.0001 with stature, 0.210±0.0001 with body depth, 0.11±0.0001 with rump angle, 0.19±0.0002 with rump width, 0.14±0.0001 with rear udder height, 0.20±0.000001 with central ligament, 0.14±0.0000001 with rear teat placement, 0.13±0.0001 with rear udder width, 0.14±0.0000001 with udder balance, 0.09±0.0001 with thurl width and 0.12±0.0000001 with temperament.
Phenotypic and genetic correlations of most the linear type traits with score day milk yield were generally higher than with 305 days milk yield. Phenotypic correlations with score day milk yield were observed as 0.09±0.03 for stature, -0.21±0.03 for chest width, -0.05±0.04 for body depth, -0.17±0.03 for angularity, -0.12±0.03 for rump angle, -0.16±0.05 for rump width, -0.32±0.03 for rear legs set, -0.16±0.04 for rear legs rear view, -0.22±0.03 for foot angle, -0.34±0.03 for fore udder attachment, -0.16±0.04 for rear udder height, -0.16±0.04 for central ligament, -0.25±0.03 for udder depth, 0.06±0.04 for front teat placement, 0.008±0.03 for teat length, -0.19±0.04 for rear teat placement, -0.15±0.04 for locomotion, -0.22±0.03 for body condition score, -0.35±0.03 for top line, -0.08±0.04 for bone structure, -0.17±0.05 for rear udder width, -0.18±0.04 for udder balance, -0.20±0.03 for teat thickness, -0.11±0.04 for thurl width and -0.11±0.05 for temperament, respectively.
Genetic correlations with score day milk yield were observed as 0.57±0.05 for stature, 0.09±0.02 for chest width, 0.31±0.04 for body depth, 0.06±0.02 for angularity, 0.15±0.03 for rump angle, 0.30±0.05 for rump width, 0.04±0.02 for rear legs set, 0.06±0.01 for rear legs rear view, 0.06±0.02 for foot angle, 0.10±0.02 for fore udder attachment, 0.18±0.03 for rear udder height, 0.12±0.02 for central ligament, 0.18±0.02 for udder depth, 0.60±0.06 for front teat placement, 0.23±0.03 for teat length, 0.07±0.01 for rear teat placement, 0.021±0.02 for locomotion, 0.12±0.02 for body condition score, 0.08±0.02 for top line, 0.08±0.03 for bone structure, 0.19±0.04 for rear udder width, 0.19±0.03 for udder balance, 0.095±0.02 for teat thickness, 0.12±0.02 for thurl width and 0.27±0.05 for temperament, respectively.
Among body measurements, head related measurements included head length, horn diameter at base, length and width of ear and poll width and their average values were found as 54.13±3.48, 18.65±2.06, 29.5±2.12 and 18.66±1.22, and 30.95±2.35 cm, respectively. Average values for neck length and neck circumference were observed as 53.32±4.56 and 95.77±8.58 cm, respectively.
The height and length of body was measured at different body points and average values were found as 139.56±6.29 cm for horizontal body length, 154.01±7.61 cm for diagonal body length, 135.77±4.4 cm for height at sacrum, 132.04±4.57 cm for height at withers, 130.77±4.61 cm for height at 6th rib position, 126.34±4.51 cm for height at last rib position, 128.89±4.83 cm for height at hook bone and 118.81±4.45 cm for height at pin bone.
The average values for heart girth, paunch girth, sprung at 6th rib position and sprung at last rib position were resulted as 194.46±10.31, 238.52±13.96, 45.15±4.48 and 68.72±5.2 cm, respectively. Mean estimates for top wedge area, front wedge area and side wedge area were obtained as 3152.79±309.53, 1030.17±136.34 and 3105.07±345.26 cm2, respectively. The length of tail and its diameter at base was measured and its value averaged 103.51±12.55 and 22.41±2.005 cm, respectively. Average values of skin thickness at neck, ribs, belly and tail region were found as 4.16±1.16, 5.85±1.36, 7.34±1.49 and 1.71±0.55 mm, respectively. Mean values for some other traits included 43.52±2.582 cm for rump length, 3.12±0.56 cm for heel depth and 523.13±81.63 kg for body weight. It was observed that herd was a significant source of variation for all body measurement traits. Age of the buffalo at classification was a significant source of variation for all of the body measurements except horn diameter at base, poll width, tail length, skin thickness at tail and height at hook bone.
Most of the body measurements have been found to be lowly to moderately heritable in the current study. Heritability estimates for various body measurements were observed as 0.16±0.09 for horn diameter at base, 0.38±0.04 for ear length, 0.06±0.09 for ear width, 0.25±0.091 for head length, 0.14±0.09 for poll width, 0.03±0.06 for neck circumference, 0.05±0.07 for neck length, 0.05±0.09 for body length, 0.05±0.09 for diagonal body length, 0.41±0.09 for tail length, 0.28±0.091 for tail diameter at base, 0.04±0.09 for skin thickness at neck, 0.02±0.09 for skin thickness at ribs, 0.10±0.09 for skin thickness at belly, 0.07±0.08 for skin thickness at tail, 0.11±0.09 for height at sacrum, 0.28±0.09 for height at withers, 0.22±0.092 for height at 6th rib position, 0.25±0.092 for height at last rib position, 0.18±0.091 for height at hook bone, 0.07±0.08 for height at pin bone, 0.04±0.06 for sprung at 6th rib position, 0.07±0.06 for sprung at last rib position, 0.13±0.09 for heart girth, 0.05±0.09 for paunch girth, 0.11±0.09 for top wedge area, 0.05±0.06 for front wedge area, 0.16±0.07 for side wedge area, 0.13±0.08 for rump length, 0.02±0.06 for heel depth and 0.33±0.07 for body weight.
Phenotypic correlations of 305 days milk yield with various body measurements were in low range. Positive phenotypic correlations ranged from 0.02±0.04 for sprung at 6th rib position to 0.17±0.05 for ear length. Some of the important body measurements have positive phenotypic correlation with 305 days milk yield as 0.15±0.04 for head length, 0.04±0.04 for diagonal body length, 0.04±0.02 for height at withers, 0.11±0.03 for height at sacrum, 0.11±0.04 for sprung at last rib position, 0.04±0.04 for heart girth, 0.08±0.03 for rump length and 0.07±0.03 for body weight. Negative phenotypic correlations with 305 days milk yield ranged from -0.03±0.03 for side wedge area to -0.25±0.03 for horn diameter at base. Some important negative phenotypic correlations included -0.25±0.03 for horn diameter at base, -0.04±0.04 for neck circumference, -0.12±0.03 for skin thickness at neck and -0.08±0.03 for front wedge area.
Positive phenotypic correlation with score day milk yield included 0.09±0.05 for body weight, 0.07±0.002 for rump length, 0.09±0.003 for sprung at last rib position, 0.09±0.005 for height at hook bone, 0.08±0.02 for height at sacrum. Rest of all the traits were low in correlation with milk yield. Negative phenotypic correlation with score day milk yield included horn diameter at base as -0.15±0.02 and heel depth as -0.13±0.04. Rest of all negative phenotypic correlations were very low.
Positive genetic correlations of 305 days milk yield varied from 0.02±0.002 for ear width to 0.23±0.02 for side wedge area. Some important body measurements have positive genetic correlation values as 0.121±0.000001 for head length, 0.162±0.000001 for diagonal body length, 0.080±0.000001 for height at withers, 0.15±0.000001 for height at sacrum, 0.15±0.000001 for sprung at last rib position, 0.14±0.0005 for heart girth and 0.16±0.007 for body weight. Negative genetic correlation for this trait was observed only for skin thickness at neck region as -0.16±0001.
About 40 traits regarding udder and teat measurements before and after milking were analysed. Average values for udder length, width, height, depth and circumference before milking were found as 52.65±6.87, 53.52±6.19, 54.34±4.99, 18.76±3.87, and 77.05±11.69 cm, respectively while the corresponding values for the same traits after milking were found as 47.08±6.57, 48.15±5.79, 55.39±5.15, 18.11±4.11 and 67.04±8.11 cm, respectively. Teat impression distances between front teats, rear teats, fore and rear teats from right side and fore and rear teats from left side were found as 12.46±3.01, 7.01±1.91, 8.08±1.8 and 7.71±1.75 cm, respectively. Pre stimulation and after milking teat characteristics were found as 12.93±3.12 and 11.71±2.83 cm for distance between front teats; 7.48±1.93 and 6.61±1.58 cm for distance between hind teats; 8.34±1.91 and 7.54±1.60 cm for distance between fore and hind teats of right side; 8.004±1.95 and 7.17±1.60 cm for distance between fore and hind teats of left side; 10.19±2.17 and 9.057±1.50 for diameter of fore right teat; 10.92±2.45 and 9.611±1.66 cm for diameter of rear right teat; 10.33±2.11 and 9.33±1.45 cm for diameter of fore left teat; 11.25±2.54 and 9.937±1.76 cm for diameter of rear left teat; 10.71±2.63 and 11.2±2.39 cm, for teat length of fore right teat; 13.05±3.27 and 13.13±3.03 for teat length of rear right teat; 11.09±2.71 and 11.88±2.61 cm for teat length fore left teat and 13.75±3.04 and 14.47±2.99 for teat length of rear left teat, respectively.
All of the udder conformation traits before and after milking were highly significantly different in different herds (P<0.0001). Stage of lactation was found to be highly significant source of variation (P<0.0001) for before milking udder length, before milking udder height, average before milking udder circumference, after milking udder length, after milking average udder circumference, teat impression distance between fore, between rear and between fore and rear teats on both sides. However, before milking average udder width, before milking udder depth, after milking average udder width, after milking udder height and after milking udder depth were not affected by this factor.
All of the above mentioned traits were significantly affected by parity except after milking udder depth and teat impression distance between fore teats and between rear teats.
Season of scoring significantly affected before milking udder length (P<0.01), before milking average udder width (P<0.05), before milking average udder circumference (P<0.01), after milking average udder width (P<0.01), after milking average udder circumference (P<0.0001), teat impression distance between fore and hind teats of left side (P<0.05). Rest of all the traits were not significantly different in different seasons.
Most of the udder traits were significantly affected by linear and quadratic effect of age of the buffalo at classification. Herd was a significant source of variation for all teat related traits recorded at pre stimulation before milking time. Stage of lactation significantly affected pre stimulation distance between front teats, pre stimulation distance between hind teats, pre stimulation distance between fore and hind teats on right and left side, pre stimulation diameter of fore right teat, pre stimulation teat length of fore right teat, pre stimulation teat length of rear right teat, pre stimulation teat length of fore left and rear left teat. However, pre stimulation diameter of rear right teat, pre stimulation diameter of fore left teat and pre stimulation diameter of rear left teat were not affected by this factor. All of these parameters were affected by parity except pre stimulation distance between hind teats and pre stimulation teat length of fore left teat. Similarly all of these traits were affected by season of scoring except pre stimulation distance between fore, between hind, between right and between left teats.
All of teat characteristics after milking were significantly affected by herd. Stage of lactation significantly affected after milking distance between fore and hind teats of right side (P<0.05), after milking teat length of fore right and rear right teat (P<0.01), after milking teat length of fore left teat (P<0.05) and rear left teat (P<0.0001). Rest of all traits after milking were not affected by stage of lactation. Most of the teat parameters after milking were significantly affected by parity except after milking distance between front and between rear teats, after milking teat length of rear right teat and after milking teat length of fore left teat. Distances among teats after milking and after milking diameter of rear left teat were not significantly affected by season. Rest of all traits were significantly affected by this factor.
Heritability estimates for before milking udder length, average udder width, udder height, udder depth and average udder circumference were found as 0.08±0.07, 0.22±0.08, 0.22±0.09, 0.05±0.06 and 0.21±0.07, respectively. The corresponding values after milking for these traits were observed as 0.14±0.07, 0.20±0.08, 0.09±0.08, 0.02±0.08 and 0.09±0.07, respectively.
Heritability estimates for before milking and after milking teat characteristics were found as 0.11±0.09 and 0.15±0.09 for distance between front teats; 0.03±0.06 and 0.03±0.07 for distance between hind teats; 0.32±0.09 and 0.06±0.07 for distance between fore and hind teats of right side; 0.16±0.08 and 00.09±0.07 for distance between fore and hind teats of left side; 0.21±0.08 and 0.11±0.08 for diameter of fore right teat; 0.05±0.05 and 0.02±0.05 for diameter of rear right teat; 0.19±0.08 and 0.25±0.09 for diameter of fore left teat; 0.07±0.06 and 0.03±0.07 for diameter of rear left teat; 0.12±0.06 and 0.08±0.06 for teat length of fore right teat; 0.02±0.05 and 0.11±0.07 for teat length of rear right teat; 0.29±0.09 and 0.29±0.092 for teat length of fore left teat and 0.14±0.08 and 0.08±0.07 for teat length of rear left teat, respectively.

Phenotypic correlations of before and after milking udder length, average udder width, udder height, udder depth and average udder circumference with 305 days milk yield were found as 0.29±0.04 and 0.18±0.04; 0.30±0.04 and 0.33±0.04; -0.26±0.03 and -0.20±0.03; 0.07±0.04 and 0.06±0.05 and 0.18±0.04 and 0.14±0.04, respectively. Corresponding values in the same order for genetic correlations were observed as 0.17±0.0002 and 0.21±0.0003; 0.33±0.0002 and 0.19±0.0003; -0.29±0003 and -0.34±0003; 0.10±0.0001 and 0.07±0.0001 and 0.28±0.0004 and 0.23±0.0003, respectively.
Phenotypic correlations of before and after milking udder length, average udder width, udder height, udder depth and average udder circumference with score day milk yield were found as 0.29±0.03 and -0.18±0.02; -0.32±0.02 and 0.17±0.01, -0.38±0.001 and -0.20±0.002, 0.28±0.01 and -0.04±0.04 and 0.21±0.04 and -0.15±0.04, respectively.
Phenotypic correlations for pre stimulation and after milking teat characteristics with 305 days milk yield were found as 0.19±0.03 and 0.07±0.03 for distance between front teats; 0.20±0.04 and 0.20±0.04 for distance between hind teats; 0.21±0.03 and 0.21±0.03 for distance between fore and hind teats of right side; 0.18±0.03 and 0.18±0.03 for distance between fore and hind teats of left side; 0.07±0.03 and 0.27±0.04 for diameter of fore right teat; -0.04±0.03 and 0.14±0.04 for diameter of rear right teat; -0.03±0.04 and 0.20±0.04 for diameter of fore left teat; -0.02±0.04 and 0.20±0.03 for diameter of rear left teat; 0.24±0.03 and 0.28±0.03, for teat length of fore right teat; -0.13±0.03 and -0.009±0.04 for teat length of rear right teat; 0.01±0.02 and 0.12±0.03 for teat length fore left teat and 0.06±0.03 and 0.22±0.03 for teat length of rear left teat, respectively.
Genetic correlations for pre stimulation and after milking teat characteristics with 305 days milk yield were found as 0.22±0.0002 and 0.12±0.0003 for distance between front teats; 0.26±0.0001 and 0.13±0.0001 for distance between hind teats; 0.11±0.0001 and 0.09±0.0001 for distance between fore and hind teats of right side; 0.10±0.0001 and 0.07±0.0001 for distance between fore and hind teats of left side; 0.11±0.0001 and 0.11±0.0001 for diameter of fore right teat; 0.09±0.0002 and 0.16±0.0001 for diameter of rear right teat; 0.001±0.000001 and 0.001±0.0001 for diameter of fore left teat; 0.001±0.000001 and 0.001±0.0001 for diameter of rear left teat; 0.080±0.00001 and 0.11±0.0001 for teat length of fore right teat; 0.07±0.000001 and 0.001±0.0002 for teat length of rear right teat; 0.003±0.000001 and 0.003±0.0003 for teat length fore left teat and 0.003±0.000001 and 0.002±0.0002 for teat length of rear left teat, respectively.
Phenotypic correlations for pre stimulation and after milking teat characteristics with score day milk yield were found as -0.37±0.02 and -0.48±0.03 for distance between front teats; 0.04±0.04 and 0.06±0.04 for distance between hind teats; 0.04±0.04 and 0.03±0.04 for distance between fore and hind teats of right side; 0.03±0.039 and 0.08±0.04 for distance between fore and hind teats of left side; -0.33±0.03 and -0.16±0.04 for diameter of fore right teat; -0.46±0.03 and -0.26±0.04 for diameter of rear right teat; -0.41±0.03 and -0.24±0.04 for diameter of fore left teat; -0.30±0.03 and -0.28±0.04 for diameter of rear left teat; -0.43±0.03 and -0.49±0.03 for teat length of fore right teat; -0.36±0.02 and -0.47±0.02 for teat length of rear right teat; -0.41±0.034 and -0.43±0.03 for teat length fore left teat and -0.28±0.021 and -0.53±0.02 for teat length of rear left teat, respectively.
Genetic correlations for before and after milking teat characteristics with score day milk yield were found as 0.13±0.016 and 0.15±0.02 for distance between front teats; 0.30±0.04 and 0.40±0.05 for distance between hind teats; 0.19±0.05 and 0.38±0.05 for distance between fore and hind teats of right side; 0.32±0.06 and 0.44±0.06 for distance between fore and hind teats of left side; 0.22±0.03 and 0.27±0.04 for diameter of fore right teat; 0.16±0.02 and 0.23±0.03 for diameter of rear right teat; 0.15±0.02 and 0.22±0.03 for diameter of fore left teat; 0.11±0.02 and 0.24±0.03 for diameter of rear left teat; 0.19±0.02 and 0.17±0.02 for teat length of fore right teat; 0.075±0.01 and 0.07±0.01 for teat length of rear right teat; 0.27±0.029 and 0.27±0.03 for teat length of fore left teat and 0.10±0.01 and 0.08±0.01 for teat length of rear left teat, respectively.
Least squares means for various performance traits were found as 7.02±2.46 for score day milk yield, 1801.61±624.59 for lactation milk yield, 2074.1±360.85 for 305 days milk yield, 2149.09±680.59 for best milk yield, 272±69 for lactation length, 408.553±203.63 for preceeding dry period, 1762.05±305.97 for age at first calving, 477.68±64.53 for weight at first calving, 110±33 for age at scoring in months, 523.133±81.63 for weight at scoring in Kg.
Most of the phenotypic studies on Nili Ravi breed are limited to recording only few body measurements. In order to explore the physical features of this breed, linear scoring system needs to be adopted which is based on measurement of certain specific parts of body as per international standards according to the ICAR guidelines. However, some of the linear scores developed for dairy cattle breeds do not fit for this breed and harmonization of certain trait definitions is needed even for the linear score system for this breed. The following points are important regarding linear scoring system for Nili Ravi buffaloes:
" In case of rump angle, the score ranging as 1-3 which refers to higher pin bone than hook bone is not present in Nili Ravi buffaloes. The score for central ligament ranging as 1-3 which refers to convex floor of udder has not been observed in this breed. The position of front teat placement as inside of quarter scoring as 7-9 has not been observed in Nili Ravi buffaloes. The position of rear teat placement as outside of quarter scoring as 1-3 has not been observed in Nili Ravi buffaloes. The score for top line ranging as 8-9 which represents a back bent upwards has not been observed in this breed. The score of 1 and 2 which represents a rear udder deeper than the fore udder has also not been observed in the present study. A higher temperament score indicates that buffaloes tend to be excited especially at the time of milking and handling. This behaviour of buffaloes needs to be improved through selection and breeding.
" A highly significant effect of herd was observed on all of the linear type traits. Effect of stage of lactation was found to be highly significant for udder conformation related traits including fore udder attachment, rear udder height, central ligament, udder depth, teat length and rear udder width. Most of the udder related traits were affected by parity such as fore udder attachment, rear udder height, udder depth, teat length, rear udder width and teat thickness. significant effect of parity was observed on chest width, angularity, rump angle, rump width, top line, thurl width, and temperament.
" Initiation of conformation recording in public and private sector and use of selective and planned breeding will be helpful for the improvement in milk yield and to bring uniformity in body features of Nili Ravi buffaloes.
" Scoring in first parity should be adopted as in later parities adjustment for age and parity will be needed.
" Differences among herds for most of the traits suggest that performance can be improved by exploiting genetic potential through selection and breeding. Heritability estimates for most of the linear type traits were found as higher than the reported values available in literature. The reasons might be due to species differences and relatively small data set as well as incomplete pedigree records. Even then the results might be considered for inclusion of some of the linear type traits in selection programs. Keeping in view that this is a preliminary study on genetic aspects of linear type traits in Nili Ravi buffaloes, further studies and research with larger data set is needed to explore linear type traits and to validate the findings of the current study.
" A positive genetic correlation of stature with milk yield suggest that taller and heavier buffaloes produced more milk and selection for taller buffaloes may result in improved milk yield but the efficiency of milk yield must be studied before making indirect selection for milk yield through stature. Negative phenotypic correlation of chest width with score day milk yield suggested that buffaloes with wider chest are relatively less efficient in milk production. Further studies are needed with larger data set to verify the results. A considerable positive genetic correlation between body depth and milk yield suggest that body depth may be considered for indirect selection of higher milk yield in Nili Ravi buffaloes. Considerable genetic correlation with milk yield suggest that rump width is important in this breed of buffaloes and can be used for indirect selection for improved milk yield. A considerable negative phenotypic correlation of fore udder attachment with milk yield is important however negligible genetic correlation suggest that fore udder attachment is independent of milk producing genes and separate selection for each trait should be considered keeping in view heritability of the trait in Nili Ravi buffaloes. A positive genetic correlation of rear udder height with milk yield suggested that selection for this trait might be helpful for improved milk yield in Nili Ravi buffaloes. Genetic correlation of teat length with score day milk yield is considerable in the current study but very low with 305 days milk yield. The findings of current study suggested that rear teat placemen has a considerable genetic correlation with milk yield and can be used for indirect selection for better milk yield. The results of current study are not in agreement with most of the reports in the literature regarding correlation of BCS with milk yield. Further research is needed to verify positive genetic correlation of BCS with milk yield before using BCS as selection criterion for milk yield in Nili Ravi buffaloes. Due to negative phenotypic correlation of body condition score with milk yield, an optimal score of below average ranging from 4 to 5 may be recommended. A positive genetic correlation of rear udder width with milk yield suggested that some of the same genes are controlling milk yield and rear udder width and indirect selection for improved milk yield is possible through selection for rear udder width in Nili Ravi buffaloes. This genetic correlation with milk yield is considerable but further studies are needed before the udder balance could be included for selection program in Nili Ravi buffaloes.
" Current study indicated that teat thickness is not genetically important with negligible correlation with milk yield in Nili Ravi buffaloes but negative phenotypic correlation is considerable and buffaloes with thinner teats are suitable for more milk production. A low but positive genetic correlation of thurl width with milk yield provides a scope for further studies to explore this trait in Nili Ravi buffaloes. Further studies are needed with relatively larger data set to explore temperament and verify its relationship with milk yield in this breed of buffaloes. Generally, the least squares means for most of the body measurements were found in the normal range and were in agreement with most of the reports in literature.
" Comparatively higher body weight was observed than the reports available for Nili Ravi buffaloes. One of the reason for this might be relatively better supply of feed and fodder during the course of study and also the records pertaining to 3rd and latter parities were more in number than the records on younger buffaloes. The top and side wedge area are almost similar with less variation showing that Nili Ravi buffaloes are relatively more wedge shaped.
" Most of the body measurements were affected by the herd and age factors but the effect of parity, stage of lactation and season of scoring was variable for different traits and showed not very clear trend. Body weight was affected by all the factors studied in the current investigation. Most of the body measurements have been found to be moderately to highly heritable in the current study. Overall range of heritability estimates for body measurements was found as 0.08±0.09 to 0.92±0.00.
" Skin thickness has been found under the genetic control and can be improved through selection and breeding keeping in view its importance and demand in the leather industry and also its correlation with milk yield.
" Diagonal body length in the current study has shown a low but positive genetic correlation with milk yield and this trait might be considered in the selection program for Nili Ravi buffaloes. The negative genetic correlation of skin thickness in the neck region with 305 days milk yield is important and advocates the thinking of farmers about the negative correlation of skin thickness with milk yield. Genetic correlation of heart girth with milk yield although not very high but seems to be important and can be considered for indirect selection for milk yield through heart girth measurement. A reasonable genetic correlation of body weight with milk yield suggested that this trait should be considered in the selection program for improved milk yield in Nili Ravi buffaloes.
" Udder colour has not been found important. Buffaloes with pendulous udders have produced more milk. The possible reason for this more milk is that such buffaloes were recorded in latter parities and age of those buffaloes was high and the size of their udder was large. The frequency of buffaloes with such type of udder is only 8%. Buffaloes with such type of pendulous udders are more prone to udder and teat injuries and mastitis and their life time production is less. Thick and lengthy teats have been observed in this breed and the reason might be due to hand milking and direct suckling of cows by the calves.
" Most of the udder traits were significantly affected by herd, parity, stage of lactation and age of the buffaloes at classification. Most of the udder measurements have been found highly heritable and this provides a good scope for improvement of these traits through selection and breeding. A general decrease in the distance between fore, rear and fore and rear teats on both sides was observed after milking. This indicated that the distance measured after milking was a good indicator of actual distance between teats of this breed irrespective of stage of lactation. Udder length, width, udder circumference and height either recorded before milking or after milking have been found genetically correlated with milk yield and they should be considered for selection decisions in Nili Ravi buffaloes. A reasonable positive genetic correlation of distance between fore and between rear teats suggested that this distance is important for milk yield and should be considered for selection in Nili Ravi buffaloes. The results of present study suggest that teat diameter is not genetically much important for milk yield and the reason of thick teats is due to hand milking and direct suckling by the calves.
" Teat distance between front teat, between rear teat, diameter of fore right and rear right teat and teat length of fore right teat have shown low but not negligible genetic correlations with milk yield and should be given some importance in making selection decisions in Nili Ravi buffaloes.
" Brown colour buffaloes have not been observed in this study because such animals at Govt. livestock farms are culled at an early age, however farmers think that such type of buffaloes are better milk yielder and they like and demand such animals, development and conservation of these animals is advocated at experimental level to study their potential.
" Further research is needed to evaluate visual image analysis system as a tool for quick and more accurate conformation recording.

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