The influence of environmental change and seasons on the sperm quality of breeding boars after relocation

Abstract

This study aimed to determine the impact of relocation as a potential stress factor on the reproductive properties of breeding boars, as well as the impact of the new environment on the quantity and quality of the semen obtained during different seasons. At the beginning of spring, 16 breeding boars (Large White (n=3), German Landrace (n=4), Swedish Landrace (n=6) and Pietrain (n=3)) were relocated from old to new housing conditions and exposed to loading, transport, unloading, and rehousing in a new environment. They had the same conditions of feeding, care, sexual exploitation and keeping, before and after relocation. The health status of all breeding boars was carefully monitored and controlled. No significant differences were observed in the total and average number of doses produced between seasons. There was a significantly higher value of total ejaculate volume and density during the spring compared to the values obtained in other seasons (P<0.01). Differences in the average percentage of mobility between autumn and winter were not significant (P=0.983), as in spring and summer (P=0.737). Ventilation rate, gas concentrations of ammonia, nitrous oxide and carbon dioxide in the boar enclosure were similar before and after relocation. Two days after relocation, one boar (ID 172) showed signs of illness and was treated, but his sperm was rejected due to sperm agglutination and reduced motility, so he was culled. Individual analysis of the production indicators showed that there was no significant change in the spermatogenesis of healthy boars, even though they were relocated.