Sexual activity of Assaf ewes after October and February lambings.
The first ovulation in 20 Assaf ewes and the first estrus in 54 out of 77 Assaf ewes after the October lambings occurred at mean intervals of 26 +/- 1.7 and 50 +/- 1.5 d postpartum, respectively. After the February lambings, nine out of 20 examined ewes had their first ovulation and estrus 35 +/- 2.5 and 71 +/- 7.7 d postpartum, respectively, and resumed normal cyclic activity in April. Five animals showed considerable ovarian activity but only occasional estrous activity during spring, while the remaining six ewes had a 6-to 7-mo-long anestrous season during which only occasional ovulations were detected in three of them.
Amir
D
D
Agricultural Research Organization, The Volcani Center, P.O.B. 6, Bet Dagan 50250, Israel.
Gacitua
H
H