Evaluation of the season of the year on the conditioned sexual behavior of rams

Abstract

The aim of this study was to compare how season of the year affects sexual behavior in rams, trained to mount a dummy. Two specimens per breed were included in a study to analyze their sexual behavior throughout the year (spring, summer, autumn and winter).Animals were trained for conditioned mounting and then, their activity was monitored by video recorder and ethograms on weekly bases (52 records / ram / year). To test the hypothesis that reproductive behavior differences occur among ram breeds during the different seasons of the year, a descriptive statistical analysis of states and events of conditioned mounting was carried out, through analysis of variance (ANOVA) and Tukey test. Results showed no differences in sexual behavior during semen collection among breeds throughout the year. In average, animals displayed the state of flehmen in 16.3 seconds and the copulation in 71.1 seconds. While the average frequency for events such as olfaction, kicking and mounting attempts was 2.1, 4.3 and 2.1 times per mating event, respectively. When considering the season of year, significant differences (P<0.05) were found among the time invested by rams to complete copulation state, for the olfaction period and for the number of kicking events, while no differences (P>0.05) were observed for the flehmen state or for the mounting event. All the animals used in this study were subjected to classical conditioning and were sexually active throughout the year. Animals had best reproductive behavior patterns during winter, while no differences among rams were observed in sexual activity during the other three seasons of the year. Our results confirm previous reports indicating that rams have best reproductive performance during winter, however reproductive behavior patterns observed in five breeds of rams during spring, summer and autumn, also confirm that rams can be used for semen collection and processing purposes throughout the year.