Pooled boar semen vs monospermic boar semen. effect on fertility, prolificacy and utter dispersion

摘要

Artificial Insemination in pig production is a well-known technology with high levels of effectiveness. There are some references to improving results using pooled semen instead of monospermic semen, related to lesser risks in young and hypoprolificboars. The aim of this study was to evaluate this technology in field conditions on farms where monospermic AI is the usual procedure. The assay was carried out on 5 closed-cycle farms between February and August 1996. 40 DUTCH-YORK boars of two different terminal lines of MARTIN MIGUEL AI STATION of PROINSERGA were evaluated using the Osmotic Resistance Test (ORT) resulting in 2 ORT groups. Each ejaculate was tested following the usual criteria, being rejected in case of not achieving the minimum quality level (Individual motitity = 4 or >, Mass motihly = 80 or >, Agglutination 1 or <, Acrosomia - 82 or >). Semen concentration was 3 X 10~6 normal spermatozoa in each, in both mono and heterospermic doses. In each heterospermic group, boars were pooledin groups of 3. Five closed-cycle farms were chosen, and for 6 monihs, heterospermic doses of the different trial groups were supplied with the monospermic doses. 3556 sows were inseminated. Heat was checked by the standing reflex to man and boar. Sowswere inseminated twice in each trial group. Sows were chosen randomising except by the cycle, to avoid this effect.