1.
Influence Of Early Weaning On Growth Performance, Plasma Metabolites And Rumen Fermentation Indices In Neonatal
by Muhammad Afzal Rashid | Prof. Dr. Talat Naseer Pasha | Prof. Dr. Makhdoom Abdul Jabbar.
Material type: ; Format:
print
; Literary form:
drama
Publisher: 2013Dissertation note: Rearing of young calves is a labor intensive and costly segment of livestock production. From birth to weaning, young calf undergoes a transition from monogastric to adult ruminant. The concept of weaning from milk at an early age is based on early development of functional rumen enabling calves to utilize low quality roughages. In current study, a series of experiments were conducted to refine the more effective weaning regime for buffalo calves and use of by-products of the ethanol production industry in early weaned cattle calves.
Conventionally, buffalo calves are kept with the dam, allowed to suckle a little amount of milk along with seasonal green forages, and weaned around the age of one year. To date, limited published work was available on growth performance and economics of buffalo calves weaned from milk at an early age. Therefore, the experiment was conducted to reduce the weaning age and evaluate the growth performance of male Nili-Ravi buffalo calves. Twenty-four male buffalo calves were assigned to one of the three treatments: continuous milk feeding (CMF), limited milk feeding (LMF), and early weaning (EW). After colostrum feeding, calves were individually fed whole milk at 10% of their BW, adjusted weekly until 6 wk of age. Thereafter, milk allowance was gradually tapered to zero in CMF, LMF and EW treatments at 12, 10 and 8 wk of age, respectively. Calf starter feed was provided ad libitum from wk 2 through wk 12 and individual intakes were recorded daily. Blood sampling was carried out form wk 6 through 12, on a weekly basis. The BW and structural measurements (HG, WH, and HW) were carried out at the start of experiment and later on a weekly basis. In young buffalo calves, the regimen of weaning at 8 weeks of age was more effective. The early weaned calves showed similar growth rate to those in the CMF and LMF by consuming more calf starter and saving a substantial amount of high priced milk. On the basis of the results of this experiment, buffalo calves successfully adapted to early weaning that might help to mitigate issues like poor growth and low returns associated with traditional calf rearing practices. Furthermore, this study effectively reduced the weaning age from 1 year to 8 weeks of age. Hence, reducing weaning age did not affect the growth performance of Nili-Ravi buffalo calves by 12 weeks of age.
Early development of the rumen is the main objective of a successful early weaning program which depends upon the amount of starter intake, VFA production, and ruminal papillae development. Studies have shown that grains in starter feed can be replaced by DDGS up to 28% of DM without compromising the growth performance and rumen development. Second experiment was planned to evaluate the effects of replacing grains and soybean with DDGS and ammonia treated DDGS at 25% of DM. Study was conducted in collaboration with dairy science department SDSU (USA). Twenty one neonatal male Holstein calves were assigned to one of the three of dietary treatments: C = 0% DDGS, DDGS = 25% DDGS, CAFEX-DDGS = 25% CAFEX treated DDGS. In a 10 week experiment, calves were fed 680 g MR through 4 week, reduced to half during wk 5, and weaned at the end of wk 5. Starter intakes were conducted daily; whereas, body weights, structural measurements were conducted at the start of experiment and then on a weekly basis. Jugular blood samples were taken on a weekly basis using EDTA and NaFl coated evacuated tubes. Rumen samples were collected from a subset of 15 calves (n=5 calves/ treatment) at wk 5, 7 and 10. At the end of experiment, four calves from each treatment were also slaughtered to determine rumen morphometric measurements (PL, PW, RWT and PC). Experiment illustrated that weight gain, structural measurements, total starter intake, DMI and feed efficiency were not affected by the inclusion of DDGS and CAFEX treated DDGS at 25% of DM in starter feeds. CAFEX treatment of DDGS improved the CP contents of DDGS from 29.5% to 40%; however, inclusion of CAFEX-DDGS in starter reduced feed intake during the pre-weaning period. Whereas, overall starter intake was higher in calves fed DDGS based starter feed indicating the effect of ammonia treatment on palatability. Lower pre-weaning starter intake, slow rumen fermentation of CAFEX-DDGS resulted in lesser BHBA concentration leading to lesser development of rumen papillae growth (PL and PW). However, there was a tendency for higher weight gain in calves fed DDGS based starter due to increase in starter intake. In the light of these results it is concluded CAFEX-DDGS can be included in starter feeds at 25% of DM without affecting the growth performance. However, further research is required to evaluate the digestibility of DDGS after CAFEX treatement. Similar, growth performance indicates that CAFEX-DDGS can replace the corn and soybean meal in starter feeds.
In third experiment, microbial diversity in developing rumen and intestine of young calves fed DDGS and CAFEX treated DDGS at 25% of starter was investigated. Experiement was carried out at SDSU dairy research station (USA). Fifteen calves with n=5 per treatment, fed according to protocols described in Experiment II. Calves were sampled for rumen contents at wk 5, 7 and 10 of age; whereas, intestinal contents were collected at the time of slaughter. The DNA was extracted subjected to PCR-DGGE and dendogram was constructed using cluster analysis software. Results revealed that microbial population was highly different from each other at wk 10 indicating the effect of age and dietary treatment on rumen micro flora. Whereas, intestinal and rumen bacterial diversity at wk 5 and 7 of age was not affected by inclusion of DDGS and CAFEX-DDGS in starter feed. The changes in intestinal microflora of DDGS and CAFEX-DDGS fed calves compared with control group showed that the effect of dietary treatments on post-ruminal availability of nutrients and microbial proteins. In conclusion, rumen bacterial population changes with the advancing age and the type of ingredients used in the diet. Further, research is required to identify the effect of feeding DDGS on growth of particular bacteria like methanogen and their impact on methane production and feed efficiency.
Availability: Items available for loan: UVAS Library [Call number: 1595,T] (1).
2.
Mineral Profile In Ruminants Of Canal Lrrigated Districts Of Punjab And The Effect Of Dietary Cation Anion Diffference on Lactational Performance of Nili Ravi Buffaloes and Beetal Goats
by Umar farooq | Prof. Dr. Talat naseer pasha | Prof. Dr. Makhdoom abdul jabbar.
Material type: ; Format:
print
; Literary form:
not fiction
Publisher: 2013Dissertation note: Abstract Availability: Items available for loan: UVAS Library [Call number: 1855,T] (1).
3.
Impact Of Digestible Lysine, Methionine + Cysteine Ratios On Growth Performance, Ileal Digestibility Of Protein And Gut Health In Broilers Fed Different Protein Sources
by Ch. Ahsan Akram (2009-VA-397) | Prof. Dr. Talat Naseer Pasha | Dr. Shafqat Nawaz Qaisrani | Prof. Dr. Athar Mahmud.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Poultry production is a vibrant segment of agriculture in Pakistan. Genetic selection and nutritional improvements resulted in accelerated growth rate and better FCR in modern broilers. This improved broiler performance requires greater amount of digestible nutrients. Since feeding cost accounts about 70% of total production cost and protein is the most expensive component of poultry diets. Future poultry diets, therefore, will be formulated by using cheaper and poorly digestible protein sources such as CM and SFM due to price volatility of highly digestible but expensive sources like SBM. The undigested protein in hind gut is subjected to microbial fermentation, results in formation of nitrogenous products that are not only harmful to birds, but also excreted into litter bedding and generate ammonia, nitrous acid and nitrous oxide, the latter one is a powerful greenhouse gas with an effect about 300 times compared with carbon dioxide. The potential solution to this problem is supplementation of synthetic amino acids in low nutrient density (CP) diets formulated by using cheaper and poorly digestible protein sources. Therefor a study was designed with the objectives to determine the impact of dLys, M + C ratios on growth performance, apparent Ileal digestibility of protein and gut health in broilers fed poorly digestible protein sources (CM and SFM). An experiment with 432 mixed sex (Ross 308) 1-d-old broilers was conducted to test the hypothesis that supplementation of Meth may improves growth performance, apparent Ileal digestibility of protein and gut health in broilers fed poorly digestible protein sources (CM and SFM). The interaction effects of the protein source (CM vs. SFM), CP levels (high vs. low) and dM+C/d Lys (recommended vs. supplemented) were tested in a factorial arrangement of 8 (2 × 2 × 2) dietary treatments. The supplementation of Meth positively influenced FI (P = 0.042), BWG (P = 0.003) and FCR (P <0.001). The broilers fed Meth supplemented diets had, on an average, 10% greater apparent Ileal digestibility of protein, 34% longer villi, 24.5% shorter crypts and 60% greater VCR compared with those fed diets with recommended levels of Meth. The levels of CP, similarly, influenced (P <0.001) the FI, BWG and FCR. The broilers fed high CP diets had 9% improved apparent Ileal digestibility of protein compared with those fed low CP diets. In conclusion, supplementation of Meth improves the broiler growth performance, apparent Ileal digestibility of protein and gut health fed poorly digestible protein sources (CM and SFM). The negative effects of poorly digestible protein sources thus may be partially ameliorated by supplementation of Meth.
CONCLUSIONS
In conclusion, the negative effects of poorly digestible protein sources thus may be ameliorated by supplementation of Meth. Supplementation of Meth above the recommended levels improves the growth performance, Ileal digestibility of protein and gut health in broilers fed poorly digestible protein sources (CM and SFM).
SUGGESTION AND RECOMMENDATION
Further research is needed to evaluate the different strategies to improve the digestibility of poorly digestible protein sources including guar meal. Threonine also has an important role in gut health so there is a need to study the effects of supplementation of threonine above the recommended levels in broilers fed poorly digestible protein sources. Feed form has pronounced effects on gut development, digestibility of nutrients and subsequent growth performance of birds. There is a dire need to evaluate the other cheaper protein sources, supplemented with synthetic amino acids and to find out a possible interaction between feed form and poorly digestible protein sources that may replace SBM in broilers.
Availability: Items available for loan: UVAS Library [Call number: 2567-T] (1).
4.
Protease Supplementation Influences Growth Performance, Gut Health And Ileal Digestibility Of Protein In Broilers Fed Low Protein Diets
by Shahzad Ahmad (2008-VA-240) | Prof. Dr. Talat Naseer Pasha | Prof. Dr. Saima | Prof. Dr. Athar Mahmud.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Proteases are protein-digesting enzymes that are used to break down the proteins of various plant materials and proteinaceous anti-nutrients in plant protein feedstuffs. The use of exogenous proteases can help in the reduction of the protein contents of a given feed by improving the digestibility and availability of the protein thereby reducing the cost of feed contributed by the protein feedstuff. It will also help to reduce the nitrogen excretion by the poultry and will contribute to mitigate the climate change.
In the present study the protease from a bacillus lachniformis spp was supplemented to evaluate the effect of enzyme on protein digestibility, gut health and birds performance. For this three experimental diets with 21, 19 and 17 % CP (HP, MP and LP) with six treatments with and without exogenous protease were used in this trial to evaluate the effect of protease. Each treatment was replicated to 6 pens and 10 birds were allocated to each pen. Parameters studied regarding birds performance were feed intake, weight gain and FCR. All the growth performance parameters were recorded on weekly basis while the Ileal digestibility and gut health parameters were recorded at the 35th day of the trial. Data was analysed through completely randomized design (CRD) under factorial arrangement using ANOVA technique (Steel et al. 1997). Means were separated through Duncan’s Multiple Range test (Duncon’s, 1955) with the help of SAS 9.1.
The results of feed intake, weight gain and feed intake: gain on weekly basis showed inconsistent results, however the overall performance of the birds fed low protein diets supplemented with protease showed significant results. The gut health parameters showed the significant increase in villus height. The apparent Ileal digestibility of protein was significantly increased in the MP supplemented with protease enzyme.
36
CONCLUSION
Based upon the findings of this study it can be concluded that;
Supplementation of protease improves growth performance of the broilers however the results on weekly basis were inconsistent but overall growth performance data shows significant results.
Protease supplementation enhances the CP digestibility in 19 % diets compared to 21 % and 17 % CP diets.
The supplementation of protease enzyme improves the villus height and crypt depth: villus height in broilers.
SUGGESTIONS AND RECOMMENDATIONS
Future researchers can further evaluate the subsequent effects of the protease on growth performance and immune response in broilers.
In future the research can be conducted to determine the effect of protease on energy digestibility and immune response in broilers. Availability: Items available for loan: UVAS Library [Call number: 2601-T] (1).
5.
Efficacy Of Different Microbial Phytases On Growth Performance Carcass Characteristics And Mineral Retention In Broilers
by Muhammad Faisal Rafique (2014-VA-918) | Dr. Talat Naseer Pasha | Dr. Saima | Dr. Athar Mahmud.
Material type: ; Literary form:
not fiction
Publisher: 2016Dissertation note: Cd Crupt Availability: Items available for loan: UVAS Library [Call number: 2762-T] (1).
6.
Effect Of Feed Form And Particle Size Of Corn On Growth Performance, Protein Digestibility And Gut Health Of Broiler
by Shahzada Muhammad Zeshan Haider (2014-VA-919) | Prof. Dr. Talat Naseer Pasha | Prof. Dr. Saima | Prof. Dr. Athar Mahmud.
Material type: ; Literary form:
not fiction
Publisher: 2017Dissertation note: The presented study was conducted at control house of Department of Poultry Production, C-block, UVAS Ravi Campus. In total 480, day-old Hubbard Classic broiler chicks were procured from local hatchery, weighed at 1st day and randomly distributed to eight treatment groups in such a way that there were six replicates in each group and each replicate had 10 chicks. Eight isocaloric and isonitrogenous experimental diets were formulated. Half birds were offered crumble form of feed in whole life while half birds were offered crumble form in starter phase and pellet form in finisher phase. Four levels (<1, 1-1.5, 1.5-2 and 2-2.5mm) of corn particle size were used in each form of feed.Body weight and feed consumptionwere recorded weekly in order to calculate feed conversion ratio.Data collected were analyzed by ANOVA using factorial arrangement under CRD. Experimental means were compared using DMR test.
Birds fed diet having higher particle size (2-2.5mm) of corn had lower feed consumption, greater body weight gain and improved FCR compared to those fed smaller particle size during starter, finisher and overall phase. Further, birds fed pelleted feed had lower feed consumption, greater weight gain and improved FCR than those fed crumble form of feed.Further, different particle size of corn resulted in non-significant effect on villus height and crypt depth. Feed form also had non-significant influence on villus height and crypt depth of duodenum.Birds fed diet having higher particle size (2-2.5mm) of corn had higher apparent ileal digestibilityof protein than those fed smaller particle size. Feed form had non-significant effect on apparent ileal digestibilityof protein.
It can be concluded from the results that birds fed pelleted diet containing coarse particle size had improved growth performance and protein digestibility without adverse effect on gut health of broiler.
Availability: Items available for loan: UVAS Library [Call number: 2879-T] (1).
7.
Studies On Growth Performance And Total Tract Protein Digestibility In As Influenced By Different Dietary Inclusion Levels Of White, Par Boiled And Brown Rice Broken In Broilers
by Omar Javed (2007-VA-154) | Prof. Dr. Talat Naseer Pasha | Prof. Dr. Saima.
Material type: Publisher: 2017Dissertation note: Poultry sector is playing substantial role in agriculture sector of Pakistan. In the present era extensive research in poultry sector has brought vital changes which are accelerating growth and lowering feed conversion ratio. Nutritional improvements in the poultry dietsare improving the growth performance and nutrient digestibility. Poultry diets are majorly formulated cost effective for the sustainability of poultry industry and its consumers. For this reason, the main focus is on using nutritionally rich and locally available raw feed ingredients in broiler diets. Cereal grain are main energy sources used in broiler diets and among cereal grains maize is being used as a major energy source in broiler diets, but its availability, price fluctuations, incidence of mycotoxins are the major concerns and hence, a suitable alternate energy source is required. Rice broken may serve as the substitute, but, a little data is available about the efficacy of different types of rice broken at different dietary inclusion levels regarding growth performance and total tract protein digestibility studies. Therefore a study was designed with the objectives to determine the impact of different types of rice broken (white, parboiled and brown) at different dietary inclusion levels (10%, 30% and 50%) in replacement with maize on broiler growth performance and total tract digestibility of protein. An experiment with 1-d-old 600 Cobb-500 broilers was conducted to test the hypothesis that rice broken from different sources may successfully substitute maize in broiler diets. The effects of the energy sources (white broken rice, parboiled broken rice and brown broken rice) and dietary inclusion levels(10%, 30% and 50%) were tested by using one way ANOVA under Completely Randomized Design and red maize as a control diet was used. The broilers fed different energy sources had significant variation in body weight gain and feed conversion ratio. Better body weight gain and feed conversion ratio was observed in control group followed by white broken rice and lower body weight gain and highest feed conversion ratio was observed in birds fed brown rice broken in diets, similarly total tract digestibility of protein was observed higher in birds fed 50 % maize (control group) and birds fed white rice in diets up to 30% inclusion level and lower total tract digestibility of protein was observed in birds fed brown rice broken in diets. The results of the study showed that red maize is the most beneficial energy source used in broiler diets and white rice broken could be used as good alternative energy source as compared to other types of rice broken i.e. parboiled and brown.
CONCLUSIONS
In conclusion, white rice broken can easily substitute maize up to 30% dietary inclusion level in broiler but other types of rice broken i.e. parboiled and brown give comparatively good results in terms of growth performance and total tract protein digestibility up to 10% dietary inclusion level in broilers.
Availability: Items available for loan: UVAS Library [Call number: 2878-T] (1).
8.
Studies On Growth Performance And Total Tract Protein Digestibility In As Influenced By Different Dietary Inclusion Levels Of White, Par Boiled And Brown Rice Broken In Broilers
by Omar Javed (2007-VA-154) | Prof. Dr. Talat Naseer Pasha | Prof. Dr. Saima | Jibran Hussain.
Material type: Publisher: 2017Dissertation note: Poultry sector is playing substantial role in agriculture sector of Pakistan. In the present era extensive research in poultry sector has brought vital changes which are accelerating growth and lowering feed conversion ratio. Nutritional improvements in the poultry dietsare improving the growth performance and nutrient digestibility. Poultry diets are majorly formulated cost effective for the sustainability of poultry industry and its consumers. For this reason, the main focus is on using nutritionally rich and locally available raw feed ingredients in broiler diets. Cereal grain are main energy sources used in broiler diets and among cereal grains maize is being used as a major energy source in broiler diets, but its availability, price fluctuations, incidence of mycotoxins are the major concerns and hence, a suitable alternate energy source is required. Rice broken may serve as the substitute, but, a little data is available about the efficacy of different types of rice broken at different dietary inclusion levels regarding growth performance and total tract protein digestibility studies. Therefore a study was designed with the objectives to determine the impact of different types of rice broken (white, parboiled and brown) at different dietary inclusion levels (10%, 30% and 50%) in replacement with maize on broiler growth performance and total tract digestibility of protein. An experiment with 1-d-old 600 Cobb-500 broilers was conducted to test the hypothesis that rice broken from different sources may successfully substitute maize in broiler diets. The effects of the energy sources (white broken rice, parboiled broken rice and brown broken rice) and dietary inclusion levels(10%, 30% and 50%) were tested by using one way ANOVA under Completely Randomized Design and red maize as a control diet was used. The broilers fed different energy sources had significant variation in body weight gain and feed conversion ratio. Better body weight gain and feed conversion ratio was observed in control group followed by white broken rice and lower body weight gain and highest feed conversion ratio was observed in birds fed brown rice broken in diets, similarly total tract digestibility of protein was observed higher in birds fed 50 % maize (control group) and birds fed white rice in diets up to 30% inclusion level and lower total tract digestibility of protein was observed in birds fed brown rice broken in diets. The results of the study showed that red maize is the most beneficial energy source used in broiler diets and white rice broken could be used as good alternative energy source as compared to other types of rice broken i.e. parboiled and brown.
CONCLUSIONS
In conclusion, white rice broken can easily substitute maize up to 30% dietary inclusion level in broiler but other types of rice broken i.e. parboiled and brown give comparatively good results in terms of growth performance and total tract protein digestibility up to 10% dietary inclusion level in broilers.
Availability: No items available
9.
Evaluation Of Different Strategies To Improve The Dietary Nitrogen Efficiency In Lactating Dairy Cows In Pakistan
by Muhammad Imran (2005-VA-09) | Prof. Dr. Talat Naseer Pasha | Dr. Muhammad Naveed ul Haque | Dr. Muhammad Qamer Shahid.
Material type: ; Literary form:
not fiction
Publisher: 2017Dissertation note: The objectives of this study were to optimize the protein supplies and replacement of SBM with locally available ingredients in the rations of high producing Holstein Friesian cows at mid lactation. On the basis of these objectives, three experiments were conducted. Multiparous cows in mid-lactation received three treatments in a 3×3 Latin square design with a period length of 20 d. Number of animals used were nine in 1st and 3rd experiments and 12 in 2nd experiment (Table 6.1). The trials were conducted at a corporate dairy farm. When we compare the initial and final values of milk yield, milk fat and milk protein contents, there is not a big difference of our diets with that currently being practiced in Pakistan (Table 6.1). This also reveals that the experimental milk production was close to pre-experimental milk production indicating that a successful dietary transition was achieved. Table 6.1: Demonstration of parameters before and during the experiments Exp.
Cows
No.
Initial Parameters During Experiment Parameters
DIM Milk
yield (kg)
Milk
fat (%)
Milk
protein (%)
Milk
yield (kg)
Milk fat
(%)
Milk
protein (%)
1 9 113±25 32±4.1 3.65 3.25 29.7±3.1 3.70 3.27
2 12 153±44 23.3±2.1 3.99 3.34 24.7±1.8 3.98 3.31
3 9 109±19 34±3.7 3.71 3.19 30.7±2.5 3.64 3.21
Exp., experiment; DIM, days in milk In the 1st experiment, three dietary treatments were designed to provide similar energy and increasing supply of MP (g/d)—2371 (low), 2561 (medium), and 2711 (high). Increasing the MP supplies did not modify DMI; however, it increased milk protein, fat, and lactose yield linearly. Similarly, FCM increased (9.3%) linearly due to an increase in both milk yield (5.2%) and milk fat content (7.8%). Milk nitrogen efficiency decreased from 0.26 to 0.20, whereas, the
Summary
102
metabolic efficiency of MP decreased from 0.70 to 0.60 at low to high MP supplies and it average value across the treatments was 0.64 (Table 6.2). In conclusion, increasing the MP supplies resulted in increased milk protein yield; however, a higher BUN and low MNE indicated an efficient utilization of dietary protein in low MP supplies. Milk nitrogen efficiency ranges from 20 to 30% in dairy cows at mid stage of lactation. Milk nitrogen efficiency increases slightly but linearly with the increase of dietary protein up to a certain level of supply of protein. At high protein levels of dietary protein MNE is low and vice versa. In the 2nd experiment, the response of balancing metabolizable Lys to Met ratio (3:1) in low protein diets was investigated. Three experimental diets; 1) LP−: low protein diet (13.6% CP) with imbalanced Lys to Met ratio (3.33), 2) LP+: low protein diet (13.5% CP) with balanced Lys to Met ratio (2.94) through HMBi; and 3) HP−: high protein diet (14.7% CP) without balancing Lys to Met ratio (3.39) in a 3×3 Latin square design were designed. Milk yield of LP- was 0.85 kg/d less as compared with the average milk yield of LP+ and HP-. Dry matter intake decreased by 0.7 kg/d in LP+ compared to HP- treatment whereas milk yield tended to be higher by 0.7 kg/d and protein yield by 23 g/d. Balancing the Lys to Met ratio by supplementing HMBi through feed increased feed, N, and MP conversion efficiencies to milk by 4.4, 1.6, and 13.1% respectively compared to the HP- diet. Similarly, 4% FCM was increased by 4.4% in LP+ diet as compared to HP- diet. Moreover, plasma urea concentration was numerically less in LP+ compared to LP- and HP- treatments whereas no effect was observed on plasma glucose and TG concentrations. In the 3rd experiment, three diets 1) Control: with low protein with SMB as a protein source, 2) SBMD: high protein diet with SBM as a major protein source and 3) CGMD: high
Summary
103
protein diet with CGM as a major protein source. Increasing the protein supplies did not affect DMI, milk fat yield, and milk fat and lactose contents in SBMD and CGMD diets compared to the control diet. Similarly, MP balance and MP/NEL increased by 31.5 and 9.1%, respectively. Increasing the protein supplies tended to increase milk yield. Similarly, milk protein and lactose yield increased by 3.5 and 3.3%, respectively. Milk protein contents tended to increase by 1.5% in SBMD and CGMD treatments compared to the control. Increasing the dietary protein supplies increased FE in SBMD and CGMD treatments compared to control, whereas, MNE decreased by 10.9%. No effect was observed on DM, N and NEL intakes when SBM was partially replaced with CGM. Consequently, milk yield, milk components’ yield, milk composition and feed efficiency remained unaffected. Contrary to this, MNE decreased by 5% in CGM treatment compared to SBM. There were no dietary treatment effects on blood metabolites including BUN, glucose and TG concentrations, which means neither replacement of SBM nor concentration of protein in the diet affected the blood metabolites profile. There was no change in lactation performance of cows by the partial replacement of SBM with CGM. Therefore, SMB could be partially replaced with CGM with urea without affecting animal performance, and saving the feed cost. Table 6.2: Effects of experimental diets on different parameters Exp.
MP
efficiencies
Δ MP
efficiencies (%)
Δ MY
(kg)
Δ DMI
(kg)
Δ milk
fat (%)
Δ milk
protein (%)
1 0.64 14.3 5.20 0.10 7.80 5.30
2 0.65 11.6 1.20 0.70 3.93 1.50
3 0.68 9.85 1.10 0.20 2.18 1.10
Exp., experiment; MP, metabolizable protein; MY, milk yield; DMI, dry matter intake
Summary
104
In conclusion, balancing Lys to Met ratio at low protein diets and partial replacement of SMB with CGM is a mean to improve the MNE and reduce feed costs. 6.1 Conclusion and Recommendations Diets with low MP supply result in high MNE and better utilization with low levels of BUN. Although there was less milk yield in low protein diets but utilizing efficiency was high. Low protein corn-soy-based diets supplemented with rumen protected Met (HMBi) result in increased utilization of protein and low levels of BUN. Partial replacement of SBM with CGM plus urea showed no change in DMI, milk yield. Milk nitrogen efficiency was slightly decreased in CGM diet as compared to SBM diet. Feed cost could be saved by replacing 35% SBM with CGM provided that RDP is balanced by using NPN sources. Diets should be given with possible lowest protein levels having balanced AA particularly Lys and Met, which should be 3:1. High levels of protein could result into increased emission of gases to the environment. Soybean meal replacement with CGM along with some NPN source results in similar outcomes. First strategy is the best out of three currently tested and it can save money. 6.2 Future Perspectives Studies must be conducted to investigate the effects of further lowering the dietary protein levels without affecting milk production in Holstein cows. It will help to improve the dietary N utilization for milk synthesis. The above-mentioned strategies can also be tried simultaneously for improved protein/N utilization in dairy cows. Lysine can also be tried along with Met to balance the low protein corn-soy-based diets. On the basis of RDP and RUP values, other ingredients can also be tried to partially replace SMB. Availability: Items available for loan: UVAS Library [Call number: 2920-T] (1).
