Consequence of dam genotypes on productive and reproductive performance of dairy cows under the rural condition in Bangladesh.

The main objective of the present study was to evaluate the consequence of dam genotypes on productive and reproductive performance of different cross-bred dairy cows under field condition. A total of 313 dairy cow's information were collected from 33 Artificial Insemination (AI) Sub-centers/Points from the District AI center of greater Rajshahi district for a period from 1993 to 2002. The information of the productive and reproductive parameters were analyzed from questionnaires answered by 33 field assistant (artificial inseminator) and owner's of cow in respective of AI Sub-Center/Points as well as from reading the AI and 100% progeny collection Registers. In general, the mean birth weight, age at puberty, age at first fertile service, age at first calving, gestation length, post-partum heat period, days open, wastage day, service per conception, milk production per day, peak milk production per day, lactation length, lactation yield, dry period, weaning period and calving intervals were 18.8 kg, 27.9 month, 29.2 month, 38.7 months, 278.7 days, 139 days, 160 days, 20.3 days, 1.62, 5.13 L, 10.45 L, 282 days, 1445 L, 146 days, 10.65 months and 438 days, respectively. Dam genotype of dairy cows were divided into 5 groups according to their genetic composition. LxF, SxSL, L, LxSLxF and LxSxSL of dam genotype had significant effect on all the productive and reproductive performances of the dairy cows except on age at first calving, gestation length and weaning period. The genotypes of dam's of cows like LxF and LxSL showed a better performance under field condition at greater Rajshahi district and poor performance were recorded in L and LxSxSL of dam genotype. The experiment reflects that the LxF and LxSL genotypes of dam showed the better productive and reproductive performances of dairy cows under rural condition in Bangladesh.