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Background: Rajasri, a synthetic dual purpose variety suitable for backyard rearing. The current study was aimed to study the inheritance of Rajasri birds. Methods: This study was carried out during April 2019 to August 2019 at poultry research station, Hyderabad. Data collected on 6980 chicks produced from 220 sires and 660 dams in half sib mating in 4 hatches were utilized to estimate the genetic parameters. Result: Highly significant (P<0.01) influence of hatch and sex on body weights and average daily gains and shank length was observed. The overall least-squares means of body weights at birth, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 weeks of age were 32.35±0.4, 80.87±0.17, 184.29 ±0.44, 351.49±0.76, 576.16±1.10, 741.31±0.97, 878.03±0.91, 1038.9±0.91, 1160.61±0.99, 1271.59±1.27 and 1370.64±1.72g and shank length at 4 and 6 weeks of age were 47.49±0.05 and 62.18±0.06 mm, respectively. The overall least-square means of average daily gain peaks at 6-8 weeks age. Heritability estimates of body weights through sire component ranged from 0.04±0.016 (BW20) to 0.44±0.05 (BW0). Genetic and phenotypic correlations among body weights were ranged from 0.02±0.14 (BW6-BW14) to 0.98±0.01 (BW16-BW18) and 0.003±0.01 (BW2-BW20) to 0.93±0.01 (BW18-BW20), respectively. [ABSTRACT FROM AUTHOR]

Study was conducted to evaluate the performance of Soviet Chinchilla and Californian White rabbit breeds maintained in tropical environment at rabbit research station, Hyderabad, Telangana. Data generated on total of 1364 bunnies, 701 belongings to the Soviet Chinchilla born in 122 litters and 663 bunnies of Californian White born in 124 litters during the period from 2012 to 2015 were utilized to examine the various productive performance traits. The overall least-squares mean litter size and litter weight was 5.52 ± 0.16 and 264.75 ± 7.86 at birth and 3.56 ± 0.17 and 1439.67 ± 72.55 g at weaning, respectively. The overall least-squares mean pre weaning body weights were 48.39 ± 0.48, 113.65 ± 1.38, 161.50 ± 2.03, 226.15 ± 3.47, 417.89 ± 7.53g at birth, 1, 2, 3 and 4 weeks of age and the post weaning weights at 6, 8, 10, 12, 14 and 16 weeks of age were 628.75 ± 13.02, 844.11 ± 14.81, 1040.79 ± 16.42, 1225.96 ± 17.81, 1437.57 ± 20.54 and 1636.99 ± 28.87 g, respectively. Season of birth and litter size at birth showed significant (≤0.01) effect on body weights while genetic group, parity of the doe and sex of the bunny had slight effects only. The low to high heritability estimates, genetic and phenotypic correlations of body weights are the indication for improvement of body weights by appropriate breeding plans. [ABSTRACT FROM AUTHOR]

The body weights of large white Yorkshire (LWY) crosses (50 and 75 per cent) were analyzed from birth to weaning. The overall least squares mean body weights were 1.13 ± 0.02, 2.13 ± 0.01, 3.19 ± 0.02, 4.29 ± 0.02, 5.41 ± 0.03, 6.48 ± 0.03, 7.55 ± 0.04, 8.72 ± 0.05 and 9.97 ± 0.06 kg at birth, 1, 2, 3, 4, 5, 6, 7 and 8 wks of age, respectively. Genetic group, period, parity and litter size group affected all pre-weaning body weights highly significantly except for the non-significant effect of season on body weight at birth. Sexual dimorphism in favour of males was evident from 1 to 6 weeks of age. Body weights of piglets born in rainy and winter seasons and those from smaller litters recorded significantly higher body weights. Moderate to high heritability estimates were observed for body weights. The genetic and phenotypic correlations among the body weights studied ranged widely but were all positive. [ABSTRACT FROM AUTHOR]

Effect of genetic and non genetic factors on post weaning body weights (BW) and average daily gains (ADG) of broiler rabbits reared under cage and deep litter systems were studied by using least squares analysis. Effects of genetic group, season and litter size at birth were highly significant on BW and ADGs. Rearing system did not influence the BW but had a significant influence on ADGs at 9-10 and 15-16 weeks age. Sex of bunny significantly influenced the body weight at 16 weeks only. The BW and ADGs during some periods were significantly higher in winter born bunnies. Litter size significantly influenced BW and ADGs at most periods. Overall mean BWs at 6, 8, 10, 12, 14 and 16 weeks and ADG during 5-6, 7-8, 9-10, 11-12, 13-14 and 15-16 weeks were 551.89 ± 16.84, 684.30 ± 19.68, 856.37 ± 23.33, 1018.79 ± 28.83, 1207.18 ± 31.98 and 1352.84 ± 37.93 and 17.55 ± 1.04, 9.06 ± 0.73, 10.91 ± 0.80, 10.46 ± 0.94, 14.47 ± 0.90 and 10.98 ± 1.0 g, respectively. Heritability estimates and correlations for some of the traits which could be estimated are presented. [ABSTRACT FROM AUTHOR]

Data on body weight at 4 weeks age, age at first egg and cumulative egg production up to 12, 16 and 20 weeks of age of a total 617 Black and Brown strains of Japanese quails were analyzed. Strains, generations and hatches had significant influence on all the traits studied. Black quails were significantly heavier and laid more eggs. The quails of fifth generation recorded lowest least-squares mean for age at first egg with higher egg production. Heritabilities varied from moderate to high in Black and were high in Brown strains. Genetic and phenotypic correlations among the traits varied from low to high. [ABSTRACT FROM AUTHOR]