ACTORS ASSOCIATED WITH PREGNANCY LOSSES IN FRIESIAN COWS RAISED UNDER EGYPTIAN CONDITIONS

A total of 1,486 records for dairy Friesian cows from 2007–2015 wereanalyzed to investigation the factors associated with pregnancy losses orabortion raised under Egyptian conditions. The overall incidence of pregnancylosses was 9.89% in this study. The results showed that the cow age at theconceived insemination in Friesian cows having≤16 and ≥ 96.1 months ofage was significantly (P<0.01) associated with high incidence of pregnancylosses compared with that having 16.1 to 96 months. Also, extreme bodyweight at the conceived service was related to pregnancy losses, cows having≤400 and ≥600 kg of live body weight showed higher percent (P<0.01) ofpregnancy losses (13.51 and 20.59%) compared to7.94 and 8.69% in cowsweighted 401 to 499 and 500 to 599 kg respectively. The cow's parity was
significantly (P<0.01) associated with incidence ofpregnancy losses, cowshad 4th, 5thand ≥6 parities were higher than that of 1st, 2nd and 3rd parities.Summer season recorded highest incidence of pregnancy losses compared to
the other seasons. In addition, pregnancy losses was higher (P<0.01) in cowshad high milk yield
(≥20 kg daily milkdaily) than cows inlow and moderatemilk yield (≤6 to 15~20 kg daily milk daily) respectively. Nutrition system-1showed significantly higher (P<0.01) association with the incidence of
pregnancy loss compared to nutrition system-2. Either somatic cell count(SCC) or mastitis infection at insemination in Friesian cows were significantly(P<0.01) high associated with incidence of pregnancy losses in cows having
>400,000 SCC\ml of milk than that having≤ 200 and ≤ 400000 SCC\ml ofmilk.