A note on the effect of nutrition on ovulation and ovarian follicular populations in the individually fed post-partum beef heifer

Autor: S.E. Echternkamp, C. L. Ferrell, J. D. Rone, D. M. Henricks
Rok vydání: 1986
Předmět:
Zdroj: Animal Science. 43:557-560
ISSN: 1748-748X
1357-7298
DOI: 10.1017/s0003356100002774
Popis: Post-Partum anoestrus is lengthened by a thin body condition (Whitman, 1975) and malnutrition (Holness, Hopley and Hale, 1978). Post-partum nutrient intake has been implicated in both pituitary (Rutter and Randel, 1984) and ovarian (Wiltbank, Rowden, Ingalls and Zimmerman, 1964) function. Other post-partum studies, however, have shown a negligible effect of nutrition on either the pituitary (Spitzer, Niswender, Seidel and Wiltbank, 1978) or the ovary (Carstairs, Morrow and Emery, 1980). The lack of agreement among these studies may be due to an inability to control nutrient intake in all cows in a group feeding situation, or to a lack of nutrient restriction in many of the cows on a mildly restrictive diet. Furthermore, it is not clear when post-partum energy restriction is most deleterious to fertility. The objectives of this study were to examine the effect of a known individual energy intake on (i) post-partum length, and (ii) the ovarian follicular population at different stages post partum.
Databáze: OpenAIRE