The development of intersucking in dairy calves around weaning

Intersucking, i.e. sub-adult or adult cattle sucking at the udder of herd-m embers, is a problem often reported in dairy herds that leads to udder heal th problems. The causes of intersucking are virtually unknown, and until no w all available countermeasures treat only the symptoms of this behavioural problem. We examined (I) whether intersucking occurs prior to weaning and continues thereafter, and (II) whether its establishment is related to the feeding management during weaning. On 10 dairy farms, we observed the sucki ng and feeding behaviour of a group of dairy calves (2-5 animals per farm, 38 in total) 1 week before and 1, 5 and 9 weeks after weaning. Calves were weaned off milk at an average age of 21 weeks (S.D. 4.7). We analysed the c alves' food rations in order to estimate the adequacy of their energy densi ty. Thirty-five (92%) of the 38 calves performed intersucking already befor e weaning, with the frequency being highly variable between individual calv es (x(med) = 5.0 bouts/day, range 0-24.7). Calves with a high intersucking activity before weaning were likely to continue intersucking after weaning (P < 0.05). Before and after weaning intersucking could be observed at near ly every time of the day, but was most frequent around feeding. Calves with a long feeding duration (x(med) = 260 min, range 186-374) showed less freq uent intersucking 1 week after weaning (P < 0.05). In addition, the frequen cy of intersucking increased with decreasing adequacy of their rations ener gy density (r = -0.88, P < 0.01), and the highest intersucking activity was recorded on farms with restricted availability of food. The results indica te that intersucking occurs already before weaning, and its establishment m ay be prevented by a ration and a feeding management that ensures an optima l transition from pre-ruminants to ruminants. (C) 2001 Elsevier Science B.V . All rights reserved.