Variability of semen in boars treated with vitamin C in food ration

Abstract

The main criterion for keeping a boar at an insemination station is the production of boar ejaculates containing a high quantity of spermatozoa with a high fertilization potential. The production of boar semen is affected by the biological value of the boar (22,44) and by environmental factors (4, 46). As far as the biological value is concerned, the breed of the boar is considered to be of paramount importance (17,36,39,45) as it has critical influence on most semen traits. The age of the animal also plays a role (20,32,38,44). Among the environmental factors, the most important are the rearing conditions coupled with an appropriate nutrition strategy. Currently, boars of sire breeds (lines) selected for commercial use as AI sires are subjected to reproductive, fattening and slaughter evaluation.Recently, there have been reports of problems related to the deterioration of boar reproductive traits, such as reduced sexual activity and poor semen quality (2,18,19,35). There could be many reasons for that, e.g. excessive physiological burden associated with the fast growth rate resulting from intensive selection based on fattening and slaughter traits. The process of spermatogenesis can be affected deleteriously by other environmental factors, such as pesticides, exogenous female hormones and heavy metals, while positive effects may come from feed supplementation with, among others, carnitine, arginine, selenium and vitamin E. Administration of vitamins B12, B6 and PP contributes to increased sperm cell counts and improves their motility (23). Importantly, the effectiveness of