Epsilon Open Archive

Abstract

The aim of this thesis was to study the effects of restricted and free suckling in comparison with non-suckling on production and behaviour of cow and calf in dairy production systems. In the first and second study cows of Zebu × Holstein (n=24) and Holstein breed (n=27) and their calves were allocated to two treatments, restricted suckling (RS) and artificial rearing (AR) and studied during eight weeks. In the first study calves were present during milking and RS calves suckled after milking and in the afternoon. Behaviour and weight gain of calves and milk yield, milk composition and udder health (California Mastitis Test, CMT) of cows were measured. In the second study calves suckled two h after milking. Behaviour, feed intake and weight gain of calves and CMT and milk let-down of cows were registered. In the third study 65 calves of Swedish Red breed were allocated to three treatments: Free suckling (FS), low milk (LM) or high milk (HM) substitute allowance from an automatic feeder. Behaviours of FS and HM during the milk feeding period and of FS, LM and HM during weaning were observed. Weight gain and feed intake of calves were recorded until week 10. Milk yield and composition of FS dams and 15 contemporary herd-mates were measured until week 12. The result indicated an attachment between RS and FS cow-calf pairs. RS calves displayed less cross-sucking compared to AR, whereas it did not occur at all in FS during the suckling period. During the first 24 h after weaning FS showed more behavioural signs of stress than LM and HM calves. Suckling calves in all studies ate less solid feed than non-suckling calves. Weight gain was similar in RS and AR calves. Weight gain of FS calves was higher before weaning, but not after weaning compared to LM and HM. Saleable and total milk yield was higher of suckled cows in RS but not in FS compared to non-suckled cows. There were indications of improved udder health of RS compared to AR cows in extensive system. In FS system there was no effect on milk somatic cell count. In conclusion, RS resulted in beneficial effects on both production and behaviour in an extensive system. In intensive systems, RS and FS indicated benefits for calf behaviour and weight gain of FS calves; however, weight gain of FS was reduced after weaning.