Attainment of puberty in female pigs: Influence of boar stimulation

摘要: Abstract The object of the present study was to investigate whether presence a boar is importance for age at puberty and expression external heat symptoms in female pigs. Altogether 60 crossbred gilts were purchased an 12 weeks grouped, three or four per pen, separate barns (treatment groups A, B C). Treatment group A: Boars kept adjacent pens during whole period. One vasectomized penned with daily 20 min experimental period, which started mean 142 days. B: C: No boars barn any time. performed six times. Daily control carried out terminated when had passed least two oestrous cycles. Blood samples progesterone analysis taken once week. Laparoscopy all after their first observed heat. slaughtered third fourth effects treatment estimated by method squares analysis. All except one showed regular intervals A few did not stand each regardless number. Gilts belonging oestrus on average days earlier than 35 C. These differences highly significant (P