[Intersuckling by cattle: a literature review]

The literature on intersucking in cattle is reviewed. The following features are described: incidence, moments of appearance, relationship between herd mates, environmental factors (housing system, size of herd, area per animal, feeding places available, feed ration, nutrient deficiencies, housing and feeding practices during the rearing period), animal factors (genetic predisposition, social bonds, imitation), consequences (pathological changes, milk loss), and forms of symptomatic treatment (mechanical devices, surgery). It is concluded that rearing methods (bucket feeding of milk, early group housing) and genetic predisposition are likely to be the most important factors in the aetiology of intersucking in mature dairy cattle. As methods of symptomatic treatment are not successful in every case and are subject to ethical dispute, it is advisable not to treat intersucking cattle regardless of the symptomatic approach. This is the more important because there is clear evidence of genetic predisposition. The mode of inheritance is still unknown, but is likely to act through sucking motivation or drive at an early age. In problem herds more attention should be paid to rearing methods and selection of (A.I.) bulls. There also is a need for further research into the aetiology, particularly by longitudinal studies in which a large number of animals are studied from birth to first lactation.