Serum oestradiol level during matingand its effect on conception rate in thealpaca

The aim of the study was to determine the serum oestradiol level in adult alpacas during the first post-partum mating and its effect on conception rate. It was selected 85 non-lactating female adult alpacas without calf at foot. Sexual receptive females were mated with a male of proven fertility. Blood samples were collected at mating and the level of oestradiol in serum was determined by radioimmunoassay. Conception was determined by ultrasound at 25-27 days of mating. Oestradiol values were distributed in two groups: A (<0.5 pg/mL) and B (>0.5 pg/mL), where the mean was 0.78 ± 0.39 pg/mL. Conception rate in alpacas with low oestradiol level at time of mating was 52.5% and in alpacas with high level was 66.7% without significant difference. Results indicate the lack of influence of oestradiol levels on conception rate.