ABSTRACT
Abortion and stillbirth are serious problems in cattle breeding, from
both economic and animal management standpoints. This study aimed to
determine the factors that affect the occurrence of abortion and stillbirth
as well as to investigate their effects on the subsequent reproductive
performances under Egyptian conditions. The total number of records
used in this study was 2098 records. The results showed that the overall
incidence of abortion and stillbirth were 3.77 and 5.05%, respectively.
Logistical regression analysis revealed that the season and cow parity
were the important risk factor for the occurrence of abortion. While cow
breed, the season, and cow parity were the important risk factor for the
occurrence of stillbirth. The odds ratio showed that the likelihood of
occurrence of abortion in cows during the summer was significantly
increased (P=0.024) compared to the spring. Also, cows with a parity of
3 or higher were significantly related (P=0.011) to the occurrence of
abortion compared to the cows with first parity. In addition, the odds
ratio showed that the likelihood of incidence of stillbirth in Friesian cows
was increased (P=0.001) by 2.89 times compared to crossbred cows. The
summer season recorded the highest incidence of stillbirth compared to
the other seasons. The cows parity was significantly (P<0.05) associated
with the incidence of stillbirth, cows had 1st parity was higher than that of
3rd or higher parities. Cows had significantly longer days (P<0.05) to the
first service, days open and calving interval (83.9, 138.9, and 432.7 days,
respectively) after abortions and (126.5, 182.9, and 478.0 days,
respectively) after stillbirths, compared with those that had normal
calving (75.1, 109.4, and 403.2 days, respectively).