Performance And Immune Response Of Layers Among Different Production Cycles Influenced By Body Weight Losses During Molting
Material type: Book ; Literary form:
Publisher: 2016 Dissertation note: Molting is a natural phenomenon in birds to rejuvenate their potential and body reserves. Commercially molting is being practiced in most of the countries to extend the production cycle of the bird and gain more from a single birds. It also reduces the cost of rearing the replacement pullet and increase egg size. The success of molting depends on loss of body weight during molting. Genetic improvement is a continuous process and new strains of layers are being developed on regular basis. LSL Lite is one of the recently introduced strain in Pakistan. But, its optimum body weight loss during molting in different production cycles is need to be optimized. The present study was planned to compare the performance of birds after different body weight losses during molting in different production cycles of commercial LSL Lite strain. The study was conducted at a Commercial layer farm. A total of 216 uniform weight birds of three production cycles (1st Cycle = 16 Wk, 2nd Cycle = 80 Wk, 3rd Cycle = 108 wk) were placed in battery cages. The birds of 2nd and 3rd production cycles were first molted till reduction of 20, 25, and 30% body weight loss. The birds of 1st production cycle (Control group) were those having same body weight as those of 2nd and 3rd production cycle after molting. The birds used in 3rd production cycle were first molted at the age of 64 Wk. Each treatment was replicated three times with 8 birds each and placed according to Completely Randomized Designs. The parameters used were post-moult production performance, egg geometry, egg quality and immune profile of these birds. The data collected were subjected to ANOVA under Completely Randomized Design in factorial arrangement using SAS 9.1. Significant means (P<0.05) were compared using Duncan’s Multiple Range test. Results of the present study showed that birds in 1st production cycle have highest egg production %, better FCR per dozen eggs and per kg egg mass, shape index, egg surface area,
Huagh unit, yolk index, shell %, egg shell thickness. Whereas birds in 3rd production cycle have highest feed intake. Egg weight was highest in 2nd and 3rd production cycle. Similarly birds in low weight category have highest egg production %, better FCR per dozen eggs and per kg egg mass. Whereas birds heavy weight category had highest egg mass. Non-significant difference were observed regarding immunity in different production cycles and body weight loss categories. Similarly non-significant difference were observed regarding egg quality with respect to body weight loss categories throughout the experiment. Feed intake and egg production remained non-significant in case of interaction of production cycles and body weight loss categories.
From present studied it can be concluded that:
Different production cycles influence productive performance of the birds, especially 1st production cycle birds had higher production % FCR per dozen eggs and FCR per kg egg mass however the production performance of 2nd and 3rd production cycles birds is relatively comparable. Similarly 2nd and 3rd production cycle birds exhibit higher egg weight and egg mass.
Birds of low weight category (< 1400 g) of 1st production cycle and 30% body weight loss groups of 2nd and 3rd production cycles had relatively higher egg production %, better FCR per dozen eggs and FCR per kg egg mass. Whereas heavy weight category of 1st production cycle and 20 % body weight loss groups of 2nd and 3rd production cycle had higher egg weight and egg mass.
Egg quality and geometry was influenced by production cycles but no difference was observed by body weight loss categories in this regard.
Different production cycles and body weight loss categories did not influence immune parameters.
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Welfare Assessment Of Wild Turkeys (Meleagris Gallopavo) Subjected To Free Range, Semiintensive And Confinement Rearing Systems
Material type: Book ; Literary form:
Publisher: 2016 Dissertation note: The volume of turkey production is as small compared to the broiler production, although, the
turkey industry has attained a significant increase since 1980, rising from 122 million to 226
million turkeys by 2006 within the European Union, while values of turkeys produced in the US
during 2010 was $4.37 billion. The s scientific literature about welfare of confinedly reared
turkeys is scarce compared to other poultry birds. There is a need for more insight into the
factors that enhance turkey welfare, not only to sustainable production of turkey meat where the
public demands s management practices for the welfare of turkeys, but also because the
information is needed to decrease losses due to poor performance of the birds.
Besides ecological importance, Meleagris gallopavo also have aesthetic values which
mainly contribute to decline in population of turkeys due to poching in their native habitat.
Demand for poultry meat is increasing throughout the world, due to of its lower cost when
compared to other meats such as pork and beef, and also lower fat content and excellent source
of protein. The consumption of turkey meat is about 4.7 million metric tons annually throughout
of the world and with the US accounting for 50% of all consumption.
A total of 120, day-old turkey (Maleagris gallopavo) chicks were arranged into four
groups. Four diets having varying levels of crude protein (CP) viz. 16% CP, 18% CP, 20% CP
and 22% CP were prepared and were designated as control (T0), treatment 1 (T1), treatment 2
(T2) and treatment 3 (T3) diets, respectively. Group 1 birds were fed with T0 diets, group 2 with
T1 diets, group 3 with T2 and group 4 birds were fed with T3 diets. Significantly higher weight
gain 2950.86±1952.58g, body length 30.064±11cm, beak length 3.53cm, body girth
43.41±16.30cm, thigh length 18.18±6.47cm, sternum-length 11.98±4.70cm, wing-length
47.10±16.17cm, wingspan 101.36±34.32cm, shank-length and tarsus-length 13.78±4.47cm were
recorded in M. gallopavo fed with T3 diets. Feed conversion ratios (FCR) for T0, T1, T2 and T3
diets were 2.296, 2.236, 2.099 and 1.934, respectively. Internal and external quality parameters
of egg were also analyzed.
The time budget of turkeys (Meleagris gallopavo) reared under free-range and
confinement rearing systems was recorded and compared from day old chick to the sixth month
of age. Throughout the study period, M. gallopavo reared under free-range rearing system spent
relatively greater time litter pecking (23.51%) followed by walking (19.99%), feeding (16.33%),
preening (13.72%), feather pecking (6.07%), aggression (5.94%), drinking (5.90%), immobility
(2.36%), standing (2.29%) and jumping (1.96%). Similarly, the birds reared under confinement
rearing system spent relatively greater time in lying (17.82%) followed by litter pecking (15.71),
preening (12.93%), walking (11.47%), standing (8.35%), drinking (8.31%), aggression (6.85%),
feeding (6.46%), feather pecking (6.04%), immobility (4.59%) and jumping (1.46%) behavior. It
was observed during the present study that the birds reared under free-range rearing system spent
significantly greater time in litter pecking, walking and feeding behaviors as compared to the
birds reared under confinements. These behaviors are indicators of good health of the animals,
therefore free-range system is recommended over confinement rearing system for farming of M.
Growth performance, carcass yield and meat sensory quality attributes of turkeys
Meleagris gallopavo reared under free-range and confinement rearing systems were compared.
There were two treatments, i.e. indoor and free range, each containing 25 birds. In indoor
treatment, the turkeys were raised in a 20 × 20 feet (length × width) well ventilated room while
in free-range treatment, the birds were housed in an open shed having same dimensions i.e. 20 ×
20 feet (length × width), however, an additional free-range grassy paddock was provided to
them. To compare sensory attributes, 4 ready to-cook turkeys having equal size were selected
from each the rearing systems, were skinned and boneless breast fillets and thighs were prepared,
weighed and steam roasted. The roast breast meat of free-range turkeys was darker and yellower
than thigh meat from indoor birds. Score for breast meat tenderness and appearance varied
significantly (P<0.05) between free-range and confinement reared birds. However, nonsignificant
differences were recorded for thigh meat tenderness between free-range and confined
turkeys. Significantly higher (P<0.05) meat redness was recorded in thigh meat of turkeys reared
in free-range system than thigh meat of confined M. gallopavo while non-significant differences
in breast meat color were observed between free-range and confined birds. Significantly higher
juiciness and oiliness was recorded for confined birds as compared to the free-range reared
Morphological characteristics of turkey Meleagris gallopavo semen were recorded and
hatchability percentages of the artificially inseminated hens were assessed. To study the effect of
natural mating on hatchability 15 (12♀, 3♂) M. gallopavo were randomly selected and both the
genders were kept separately for two weeks, thereafter these birds were arranged in three groups,
each containing one male and four female birds. For AI, male (n = 3) and female (n = 12) birds
were kept separately through the experiment and female birds were inseminated on weekly basis.
Male birds were conditioned and trained for semen collection through abdominal massage and
morphological characteristics of the collected semen were recorded. Mean abnormal
spermatozoa rate was 14.61±1.61% with most common acrosomal defects 36.67±3.80%
followed by defects in mid-piece 8.59±0.24%, head defects 7.15±1.21% and tail defects
6.69±1.97%. Laid eggs were collected, stored and were incubated for hatching. Hatchability
percentage in artificially inseminated hens was greater 88.85% than natural mating 82.35%.
Variations in serum biochemical profile with increase in age were analyzed in turkeys
(Meleagris gallopavo). Gender-wise variations and effect of rearing systems i.e. free range,
semi-intensive and confinements were also assessed from the 1st to 6th month of age. Variations
were recorded in serum biochemical profile with increase in age. Significantly (P<0.05) higher
values of cholesterol 8.39±0.48 mmol/L, globulin 2.71±0.34 g/dL, albumin g/dL 3.82±0.58 g/dL,
total protein 5.35±0.55 g/L, urea 26.95±0.65 mg/dL, creatinine 0.83±0.01 μmol/L, alanine
aminotransferase (ALT) 35.56±1.16 iu/L and aspartate aminotransferase (AST) 44.16±1.83 iu/L
were recorded for adult birds while alkaline phosphatase (ALP) values were significantly higher
104.86±16.39 iu/L in grower birds. Similarly, the rearing systems also influenced biochemical
parameters of M. gallopavo and significantly (P<0.05) higher values for cholesterol 6.18±0.07
mmol/L and ALT 31.26±1.67 iu/L were recorded in birds reared under confinement rearing
system. Values for globulin 1.92±0.36 g/dL and creatinin 0.77±0.08 μmol/L were higher in birds
reared under semi-intensive rearing system while significantly higher urea concentrations
33.45±3.39 mg/dL were recorded from the serum of the birds reared under free range rearing
system. However, non-significant variations in albumin, total protein, ALP and AST were
recorded for all the three rearing systems.
Significantly higher values of cholesterol, globulin, albumin, creatinine and ALT were
recorded from the serum of male M. gallopavo while urea and ALP were higher in hens’ serum.
However, non-significant variations were recorded for total protein and AST among both the
genders. It can be concluded from the present study that age, gender and rearing systems strongly
influence blood biochemical profile and hence the immunity in M. gallopavo.
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Production Performance, Egg Characteristics And Immune Response In Commercial Layers Reared At Different Cage And House Zones During Summer
Material type: Book ; Literary form:
Publisher: 2016 Dissertation note: Recent trends in commercial layer farming is changing the production trends worldwide. The
commercial layer farming in Pakistan is shifting from open or semi controlled floor farms to
modern automatic controlled caged farms. These cage farms are megastructure having capacity of
huge bird rearing, due to large house dimensions the environment of house not remain uniform
throughout the house and difference in light intensity, air speed, temperature and humidity
horizontally and vertically have significant impacts on overall performance of layers. House and
cage zones in environment controlled house may influence productive performance, egg
characteristics and immune response in commercial layers. For this purpose, a total of 588 birds
arranged according to completely randomized design and divided in three house zones (Near pads,
middle and near fans) and four tier levels (Lower, Bottom, Middle, Upper) being replicated 6 times
with 9 birds in each cage. These birds were placed in ECO-60 caged house (4×4) having 9 birds
in each pen. These performance of birds were compared for differences in production performance,
egg geometry, egg quality and immune profile. Data were analyzed through factorial ANOVA
using PROC GLM in SAS software, means were compared through Duncan’s Multiple Range test.
The highest weigh gain was observed in birds reared near the pad zone followed by the birds reared
near middle and fan zone. Similarly, better egg production was found in the birds reared near
evaporative cooling pads and middle zone as compared to the birds reared near the fan zone. To
this end, better egg mass was found in the birds reared near pad and middle zone as compared to
the birds reared near the fan zone. FCR / kg egg mass was found in the birds reared near pad and
middle zone as compared to the birds reared near the fan. Regarding Infectious Bronchitis (IB), Avian
Influenza (H9), Avian Influenza (H7), Mycoplasma Gallisepticum (MG), Newcastle (ND),
difference in titters was observed among the birds of different housing zones and their interaction.
However, no significant effect of house zones, tier cage levels and their interaction was observed
regarding egg characteristics and immune response.
From the discussion in the previous chapter it can be concluded that:
In modern environment control layer house, different house zones influence productive
performance of the birds, especially near the pad zone birds exhibited improve body weight
and better production %. In the same way, birds reared near the middle zone showed better
egg mass, FCR / dozen eggs and FCR / Kg egg mass.
Among different house zones and tier cage levels, temperature, relative humidity and
thermal index varied throughout the experimental period.
Birds reared neat the pad zone at central tier had better body weight, while, better
production % exhibited by the birds reared near the middle zone at lower cage tier.
However, birds reared near pad zone at bottom cage tier revealed better FCR/dozen eggs
and / kg egg mass.
Different cage tier levels did not influence productive performance, egg characteristics and
immune response of commercial layers.
Improved immune response was shown by the birds reared in middle zone of the house as
compared to pad and fan zone while tier level did not influenced the antibody titer.
Suggestions and Recommendation
Behavioral studies are required to observe the response of bird at micro climate.
Further investigations are needed to fulfill the welfare issues of commercial layer.
Researchers should come forward to explore the alternative housing system of commercial
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