EFFECTS OF EXOGENOUS AMINES ON REPRODUCTION IN FEMALE ANGORA-GOATS

An investigation was conducted into the effects of two phenolic amines , N-methyl-beta-phenethylamine(NMP) and tyramine (T) on corpus luteum function and reproductive performance of Angora goats. Both compounds are widely distributed through the plant kingdom and, because of their sympathomimetic action, may interfere with normal reproductive proces ses. In Experiment 1, 20 nannies (xBAR = 26.7 +/- 0.96 kg) received ei ther 0. 1, 2, or 4 mg NMP in 2 ml com oil/kg BW daily, for 45 days. In Experiment 2, 75 nannies (xBAR = 32.1 +/- 0.46 kg) received either 3, or 6 mg/kg BW NMP in 2 ml com oil; 1, or 3 mg/kg BW T in physiologica l saline, or 2 ml corn oil (control) daily, for 45 days. In both studi es treatments were administered by i.v. injection. Mating was by natur al service, beginning after the start of treatment. Jugular blood samp les were collected weekly, processed to yield serum, and serum progest erone (P4) concentrations were determined by radioimmunoassay (RIA). I n Experiment 1, no dose response was detected but P4 concentrations we re reduced (P = 0.03) in the treated animals. In Experiment 2, no dose response was detected but P4 concentrations in NMP-treated animals (3 .87 +/- 0.618) were lower (P = 0.05) than in the control (5.65 +/- 0.7 47) or in T-treated animals (4.73 +/- 0.528, P = 0.08). No difference in P4 concentrations was detected between T-treated and control animal s (P = 0.59). Fewer NMP-treated nannies became pregnant (59%) than eit her control (77%) or T-treated nannies (88%) (P = 0.053). The results show that exogenous phenolic amines vary in their effect on reproducti ve performance of nannies.