Factors influencing the fertility of a cattle population.

The many factors which may influence the fertility of a cattle population are reviewed. The following subjects are discussed: the bull, the method of insemination, the cow, the conditions of herd management and chance. Particular attention is paid to factors related to the conditions of herd management. These are the climate, the season, the size of the herd, the housing system, the choice of a bull, hygiene at the time of calving, the interval between parturition and the first insemination, detection of oestrus, the time of insemination during oestrus, nutrition, selection and the culling of cows. In the discussion, the effect which the various factors may have on fertility is illustrated by a case in point.