Observations on the pathophysiology of postpartum anoestrus in mares
1989
Kulcsar, M. | Huszenicza, Gy. | Juhasz, Cs. | Schreiber, M. (Allatorvostudomanyi Egyetem, Budapest (Hungary). Szuleszeti Tanszek es Klinika) | Kezy, Gy. (Ocsai Voros Oktober Mezogazdasagi Termeloszovetkezet, Ocsa (Hungary))
In all 49 blood and half-blooded mares were investigated. They belonged to two studs and a few private breeders and foaled between January 15 and June 1. Their physical condition was moderate or even poor. Mares were systematically tested by stallions from the 7th day postpartum. Maresin oestrus were served. Blood samples were collected from the mares failing to show oestrus between the postpartum days 7 to 10 to determine the plasma progesterone level (by RIA method) 5 times with intervals of 5-7 days, starting from the 14th-21st day. In all, 28 mares were in oestrus between postpartum days 8 to 10, mostly those who foaled in months other than January of Fabruary. For the majority of mares failing to show oestrus within 10 days foaled during the same period (April - May) independently of the calendar date of foaling. Time passed between foaling and reconception showed a negative correlation with the calendar date of foaling. Mares (n=21), failing to show oestrus 10 days postpartum, belonged to 3 groups according to the development of serum progesterone level: cyclic ovarian function (n=8), corpus luteum persistent (CLP, n=8), as well as delayed onset of oestrus (n=5) could be comfirmed. The latter animals foaled during the very early period of the year (February 11). Time passed between foaling and first oestrus, as well as reconception was prolonged first of all in the case of delayed onset of oestrus and CLP.
Показать больше [+] Меньше [-]