Reproductive performance of crossbred dairy cows at Asella Livestock Research Station, Arsi, Ethiopia

In this study the reproductive performance of the dairy herd at Asella, Arsi Rural Development Unit (ARDU) Research Station between 1986 and April 1993 was evaluated. The study used to total of 330 Arsi x Friesian crossbred cows consisting of four levels of Friesian inheritance (50, 62.5, 75and 87)and involved the use of production records, breeding data, direct observation for a period of 9 months and interviewing relevant farm personnel. The overall mean ages at first service and at first calving were 30.9+/- 5.7 and 42.5 +/- 6.2 months, respectively and both traits were affected (p0.05) by the level of Friesian inheritance. The overall mean intervals from calving to first service and from calving to pregnancy were 154.2 +/-101.2 and 205.7+/- 113.7 days, respectively. Both of these traits were affected by the level of Friesian inheritance (p0.05) and year of calving (p0.001), but not by parity and season of calving. The overall calving interval was 490.1 +/- 106.4 days and was affected (p0.001) by year of calving, but not by season of calving, parity and level of Friesian inheritance. The average number of services per pregnancy was 2.15 +/- 1.4. There was a significant effect (p0.01) of season of calving but not of the level of Friesian inheritance, parity and year of calving on this trait. First service pregnancy rate for 351 first services was 44.2. The proportion of repeat breeders was 16. Rectal palpation and validation of records disclosed that only 15.7of the breeding animals were pregnant on March 17, 1993. The results of this study showed that there is low level of reproductive performance in the dairy herd. Future efforts need to concentrate on the improvement of the management and estrous detection method with training of detectors and inseminators. Improvements in record keeping, strategic nutritional supplementation and general herd health management are suggested.