The influence of various degrees of confinement and supervision on the incidence of dystokia and stillbirths in Hereford heifers

Abstract

Confinement of Hereford heifers in a pen during parturition resulted in a marked increase in the incidence of dystokia and stillbirths when cqmpared with animals left to calve in either the paddock or a large yard. The continuous presence of an observer during second-stage labour also was associated with an increase in both calving problems and assisted parturitions among penned cattle but the stillbirth rate was reduced in those animals undergoing a dystokia.

In most cases, death of the foetus or new-born calf was due to a difficult delivery. The cause of death, however, was not determined for about one-third of all stillborn foetuses found in the paddock or yard. In a few instances, the loss of new-born animals in the paddock was due to prematurity whereas in the pen, death occasionally occurred through misadventure or from suffocation by the amnion.

An increase in the degree of confinement and supervision of parturient animals was also accompanied by an alteration in the main types of calving problems encountered. Stillbirths of unknown aetiology and dystokia due to a posteriorly presented foetus constituted the 2 most important problems seen under paddock conditions. Cattle maintained in a yard prior to and during parturition were found to suffer most frequently from retained foetal membranes and dystokia involving a posteriorly presented foetus. Confinement of cattle in a pen usually resulted in a dystokia caused by vulval constriction.