Reproduction behavior and performance of beef cattle herd in free ranging environment of "Warta Mouth" national park

The observations conducted on a herd of beef cattle, extensively free grazed, demonstrated that cows in oestrus, breeding bulls (sires) and young bulls showed a wide range of sexual behavior. In the cow-cow relation mutual mounting was a standard sexual behavior, confirmed by 88.9% of observations. In the relation between sire and cow in oestrus, of the four forms of activity initiated by the cow, rubbing against a sire and mounting him was recorded in 100% of observations. The evaluation of the activity of the sire in relation to a cow in oestrus covered seven behavioral forms, of which as standard one may consider: sniffing and rubbing against, tasting the cow?s urine and mounting in an attempt at a sexual act, while mounting ended by a sexual act was not always the standard - 88.9% of observations. Young bulls manifested their sexual behavior by sniffing the cow in oestrus, often attempting to mount, following the sire and being always driven away. Driving away of the rival by a dominant sire was a standard behavior in relations between sires remaining close to a cow in oestrus. During the three year period of studies calving rate averaged 96.5%, while losses of calves as still born or dead during the first day after birth reached 1.5%. The best calving ratio was recorded for Salers cows (98.7%), while beef crossbred, Limousine, Hereford and Simmental cows demonstrated similar results (96.3-97.9%), and cows of the Charolais breed performed significantly (P?0.01) poorer (94.1%). Moreover, in the group of Charolais cows the largest percentage of still born calves (2.3%) was demonstrated.