ANTI-MULLERIAN HORMONE (AMH) SECRETION IN PREPUBERTAL AND ADULT RAMS

The aim of the present analysis was to determine whether anti-Mulleria n hormone concentrations in prepubertal plasma or adult rete testis fl uid are related to the number or function of Sertoli cells in rams or to the presence of the Fec(B) Booroola gene. Twenty rams from two Boor oola crosses, differing in their testicular masses were analysed; in e ach cross, half of the animals were heterozygous carriers of the Fec(B ) gene. The data from rams, during prepuberty and at adulthood during the non-sexual season, were analysed by two-way ANOVA and residual cor relations. In 4-week-old intact male lambs, the mean anti-Mullerian ho rmone plasma concentration was 15 ng ml(-1), irrespective of cross, ge notype or eCG stimulation; it was significantly negatively correlated with FSH (r = -0.51; P = 0.02; n = 19). In adults, anti-Mullerian horm one was not detectable in plasma and was 0.5 ng ml(-1) in rete testis fluid, irrespective of cross or genotype. The total number of Sertoli cells per testis was not related to anti-Mullerian hormone concentrati on in lamb prepubertal plasma or in adult rete testis fluid. The conce ntration of anti-Mullerian hormone in adult rete testis fluid was sign ificantly and negatively correlated with the daily production of lepto tene primary spermatocytes per testis (r = -0.56; P = 0.02; n = 16). T he mean oestrogen concentration in the adult testicular vein was 2 pg ml(-1) and was correlated negatively with the rete testis fluid concen tration of anti-Mullerian hormone (r = -0.60; P = 0.02; n = 15) and co rrelated positively with the daily production of leptotene primary spe rmatocytes per testis (r = 0.53; P < 0.05; n = 19). In conclusion, ant i-Mullerian hormone secretion was not correlated with the total number s of Sertoli cells per testis and cannot be used as a predictor of the number of Sertoli cells. Anti-Mullerian hormone secretions were not a ffected by the presence of Fec(B) gene. However, anti-Mullerian hormon e secretion could be considered to be inversely related to the daily p roduction of primary spermatocytes by the testis.