North Country Cheviot, Dorset, Finnsheep,. Romney and Suffolk rams and born from. Suffolk dams. Estrus was checked with vasec- tomized rams from July 1979 ...
Effects of Season and Breed of Sire on Incidence of Estrus and Ovulation Rate in Sheep William R. Lamberson and David L. Thomas J ANIM SCI 1982, 54:533-539.
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EFFECTS OF SEASON AND BREED OF SIRE ON INCIDENCE OF ESTRUS A N D O V U L A T I O N RATE IN SHEEP 1'2'3 William R. Lamberson 4 and David L. Thomas s Oregon State University, Corvallis 97331
Summary
The effects of season and breed of sire on estrous activity and ovulation rate were estimated in 50 mature ewes, 10 each sired by North Country Cheviot, Dorset, Finnsheep, Romney and Suffolk rams and born from Suffolk dams. Estrus was checked with vasectomized rams from July 1979 through December 1980. F r o m May through December of 1980, ovulation rate was determined by the counting of corpora lutea (CL) during laparoscopic examinations of ovaries. A breed x month interaction (P
