Relationship between the thyroidal and gonadal axes during the estrous cycle of ewes of different breeds and ages R. Peeters, N. Buys, I. Pauwels, E.R. Kühn, E. Decuypere, O. Siau and J. Van Isterdael Reprod. Nutr. Dev., 29 3 (1989) 237-245 DOI: 10.1051/rnd:19890301