Studies on the reproductive performance of crossbred dairy cows raised on smallholder farms in eastern Usambara mountains, Tanzania
Livestock Research for Rural Development
Veterinary Investigation Centre, P O Box 1068, Arusha, Tanzania; District Veterinary Office, P.O. Box 20, Muheza, Tanga, Tanzania; Divisional Dairy Development Office, P.O. Box 4, Amani, Muheza, Tanzania
A retrospective questionnaire based cross-sectional study was conducted to asses reproductive performance and factors influencing reproductive efficiency of crossbred cows in smallholder farms in Amani, Tanzania. The study was carried out during the period of October to November 2003. The study also estimated the frequency and determinants of long calving interval (LCI), retention of foetal membrane (RFM), dystocia (D), and abortion (A) in smallholder crossbred cattle and explored birth trends. Sixty-three dairy farms (average breedable cows = 2, range 1 to 9) were visited and data on reproductive, breeding and management histories were collected and statistically analyzed. Overall, 179 breedable cows were observed to be alive at some stage in 2002. These cows contributed a total risk period of 62,780 cow days, equivalent to 2,093 cow months or 171.9 cow years. The mean (±SE) calving interval and the interval between calving and the initiation of ovarian activity were 476 ± 14 and 108 ± 6.7 days, respectively. Birth rate was 52 per 100 cows years, with birth been reported to occur in all months of the year. Of the 123 cows that were reported to have calved more than once in their lifetime 4(3.3%), 3 (2.4%) were associated with abortion and dystocia, respectively. Fifteen (12.2%) of the animals suffered RFM. Significant factors that were associated with LCI and RFM as was revealed from multiple logistic regression models were age of the cows, distance range between bull source and cows, farmer attending basic animal husbandry training and the owner of the cows. Cow that was located over 2 km away from the breeding bull source was associated with LCI (Odd ratio [OR] 2.7, P = 0.020) and older cow with lower odds for RFM (OR = 0.97, P = 0.001). Animals belonging to male and a farmer who has attended a basic training had lower odds for LCI and RFM (OR = 0.31, P = 0.001 for male cow owner and OR = 0.37, P = 0.033 for attending training, respectively). Though not statistically different (P>0.05), poor reproduction performance was also linked with farm managerial factors. Under nutrition, poor heat detection despite of farmer being aware of the cardinal signs of heat, poor monitoring of heat signs due to the inadequate usage of breeding supporting tools were also found to negatively influence reproduction efficiency. We conclude that, the present estimate of LCI, birth rate, prevalence of peripartum disorders often inter linked by farm managemental attributes, indicate and suggest poor reproductive performances of cows in Amani smallholder dairy farms. Identification and quantification of the specific reproductive disorders and associated interacting factors (feeding/ managemental) contributing to such poor reproductive performance call for detailed investigation.
Animalia; Bos; Equus asinus