The present study was conducted with a view to know the productive and reproductive performance of Jamunapari, Black Bengal and crossbred goats in Chittagong district during the period of May to December 2012. The data on productive and reproductive traits were collected from 324 goats as a whole. In the present study, the birth weight of Jamunapari goats was higher than other crosses. The adult weight of Jamunapari, Black Bengal and crossbred bucks and does were 50.70 ± 3.53, 24.27 ± 1.67 and 40.38 ± 2.90 kg and 45.47 ± 3.78, 21.06 ± 2.33 and 35.72 ± 2.97 kg, respectively. The highest milk yield and lactation period were observed in Jamunapari goats than other crosses. The average ageat puberty of Jamunapari, Black Bengal and crossbred goats were 335.00 ± 25.77,194.12 ± 18.73 and 287.50 ± 22.57 days, respectively. Ageat first conceptionof Jamunapari, Black Bengal and crossbred goats were 381.00 ± 22.54, 217.94 ± 16.87 and 321.25 ± 21.25 days,respectively. Ageat first kiddingof Jamunapari, Black Bengal and crossbred goats were 534.00 ± 24.58,368.12 ± 16.96 and 471.25 ± 21.25 days, respectively. The kidding interval of Black Bengal goat was lower i.e. the reproductive performance is better in Black Bengal goat than Jamunapari and crossbred goats.Gestation period of Jamunapari, Black Bengal and crossbred goats were 151.71 ± 8.19, 146.72 ± 7.61 and 147.85 ± 7.74 days, respectively. تفاصيل المقالة

Black Bengal goat is the heritage and one of the potential genetic resources of Bangladesh. Genetic and phenotypic parameters for semen characteristics and their relationships with scrotal circumference in Black Bengal bucks were estimated in this experiment. Genetic parameters were estimated by residual maximum likelihood procedure, fitting an animal model ignoring maternal genetic or permanent environmental effects. The least-squares means of semen volume (mL/ejaculate), sperm concentration (109cells/mL), mass motility (%), sperm livability (%) and normal spermatozoa (%) were 0.56, 2.55, 79.7, 86.8 and 90.5, respectively. Season of collection and scrotal circumference significantly affected all semen characteristics studied. Age of bucks affected all the semen characteristics, except mass motility. Body weight had a significant effect on semen volume and mass motility. Heritability estimates were moderate for sperm concentration (0.38) and low for semen volume, mass motility, sperm livability and normal spermatozoa (0.05 to 0.18). Phenotypic correlations ranged from slightly negative (-0.001) to moderately positive (0.42) and the genetic correlations ranged from moderately negative (-0.37) to strongly positive (0.99). Sperm concentration was the only semen trait of Black Bengal goat where reasonable genetic progress may be possible through selection. Selection for increased scrotal circumference should have favorable correlated response in semen characteristics. تفاصيل المقالة

The objective of this study was to evaluate genetic and phenotypic parameters for some reproductive traits of Black Bengal does. Genetic parameters were estimated by Residual Maximum Likelihood procedure, fitting an animal model ignoring maternal genetic or permanent environmental effects. The least-squares means of litter size at birth (LSB), litter size at weaning (LSW), litter weight at birth (LWB), litter weight at weaning (LWW) and gestation length were 1.50, 1.29, 1.58 kg, 6.37 kg and 144.71 days, respectively. The effect of parity of doe was significant for LSB, LSW, LWB and LWW. In general, LSB, LSW, LWB and LWW increased with the progress of parity. The effect of season of kidding was significant for LSW, LWB and LWW. Estimates of heritability for LSB, LSW, LWB, LWW and gestation length were 0.08, 0.13, 0.10, 0.00 and 0.18, respectively. The low estimates of heritability obtained for reproductive traits indicated that selection based on the doe’s own performance may result in slow genetic improvement. تفاصيل المقالة

Black Bengal goat is the heritage and one of the potential genetic resources of Bangladesh. Least-squares means for body weights at birth, 3, 6, 9 and 12 months of age were 1.09, 5.12, 8.02, 10.92 and 14.47 kg, respectively. Sex of the kid has significant (P<0.05) effect on body weights at 6, 9 and 12 months of age. Type of birth and parity of the dam has significant (P<0.01) effect on birth weight only, whereas season of birth affected (P<0.05) all the body weight traits. Heritability estimates for body weights at birth, 3, 6, 9 and 12 months of age were 0.45, 0.47, 0.45, 0.49 and 0.47, respectively. Genetic correlations between body weight traits ranged from 0.34 to 0.83, whereas phenotypic correlations ranged from 0.34 to 0.90. The high heritability estimates obtained for body weights indicated that mass selection would generate substantial selection responses at all stages of growth. تفاصيل المقالة