The variables included in the model used to analyse the P AI1 were
the farms (n ¼ 2), semen (frozen–thawed or cooled), bull (n ¼
3), body-condition score (BCS) of the cows on the first day of the
synchronisation protocol (scale 1–5, where 1 ¼ emaciated and
5 ¼ obese) and interactions. The variables in which the effects
were not significant (P . 0.05) were eliminated from the model.
The percentages of sperm morphology, motility and viability
after the STRT and HOST tests were analysed by ANOVA and
mean-comparison tests (Tukey’s test; P , 0.05). The data are
presented as the mean s.e.m.