The influence of body mass and condition on ovulation rate in polyandroalbumin immunized S A mutton Merino ewes

Two groups of 40 S A Mutton merino ewes were used to determine the effect of body mass and condition score on the response of immunisation against androstenedione. The effect of immunisation was significant (P less than 0.05) on ovulation rate (1.64 for non-immunised and 2.08 for immunised ewes) and higher body mass and condition scores acted complimentary to the effect of immunisation. The ovulation rate in control ewes was more closely related to condition score (r = 0.511) and body mass (r = 0.600) at the end of the experimental period than in the immunised ewe group (r = 0.302 and 0.235).