Breeding unsoundness in the ram: the incidence of contributing conditions. 1. Northland.

Abstract

Abstract Extract Few studies have defined the incidence of those disease and other conditions that contribute to genital unsoundness in the ram. The comprehensive study by Gunn et al. (1942) Gunn, R. M. C., Saunders, R. N. and Granger, W. 1942. Studies in fertility in sheep. 2. Seminal changes affecting fertility in rams, Bull. Counc. scient. ind. Res. Melb. No. 148 [Google Scholar] provided data not only on some 9,000 rams in New South Wales and Queensland, but also on the effect that some of these conditions have on semen quality. Subsequently, workers have confined themselves to an investigation of specific entities within this field. Work is progressing within New Zealand on testicular abnormalities (Ekdahl et al., 1968 Ekdahl, M. O., Money, D. F. L. and Martin, C. A. 1968. Some aspects of epididymitis of rams in New Zealand. N.Z. vet. J., 16: 81–82. [Taylor & Francis Online] , [Google Scholar]; Bruere, 1969 Bruere, A. N. 1969. Male sterility and an autosomal translocation in Romney sheep. Cytogenetics, 8: 209–218. [Google Scholar]; Bruere et al., 1969 Bruere, A. N. 1969. Male sterility and an autosomal translocation in Romney sheep. Cytogenetics, 8: 209–218. [Google Scholar]), and chorioptic mange (A. P. Rhodes, pers. comm.). The overall situation in New Zealand is not clear. A review of two seminars on the factors affecting ram soundness has recently been published (Quinlivan; 1970 Quinlivan, T. D. 1970. Breeding soundness in the ram — a review of the proceedings and resolutions from two seminars held in 1964 and 1969. N.Z. vet. J., 18: 233–240. [Taylor & Francis Online] , [Google Scholar]). This attempt to standardize the veterinary examination of rams, in the light of present knowledge, and to establish priorities for further study, was long overdue.