Comparison of differents pen serving capacity tests in adult rams

Abstract

Parity rates need to be increased and one way to do this by improving the fertility of rams which in high percentages, are not apt for reproduction. For this, reproductive aptitude tests before service, which include serving capacity (SC) evaluation through a practical and trustworthy pen test should be carried out. This study was carried out to compare different SC pen tests.

In experiment 1, done in December, Kilgour, Laborde and Blockey's test measured similar SC (p < 0.05). Nevertheless, in experiment 2 done in February, Laborde and Blockey's tests evaluated SC differently (p > 0.05). Differences may be explained as a consequence of reproductive seasonality in rams. In both experiments, the tests estimated SC similarly whether they were done at 20 or 40minutes (p < 0.05). This allows to shorten the evaluation time for tests. This is supported in both experiments by the high correlation between reaction time to first service and total number of services (r = -0.59 y r = -0.56; p < 0.01). These results allow to think that Laborde's test may be a valid alternative of pen test of SC in adult rams in December as a complement to the classical reproductive fitness test.