Behaviour of two cow genotypes within a low input grazing system and a high input total confinement system

Resumo

Forty Holstein-Friesian dairy cows (H) and 40 Jersey x Holstein-Friesian crossbred dairycows (Jx) were randomly allocated to one of two milk production systems (a low inputgrazing system or a high input total confinement system) in a 2 x 2 factorial designexperiment. On three occasions during a six-week period, each group was observed at 20-minintervals, between 16:00-22:00 h and 07:00-14:00 h. The ‘behaviour’ of each cow wasrecorded, as follows: feeding/grazing, lying, or standing (including walking and drinking, butnot feeding/grazing) and, in addition, ruminating or non-ruminating. Average milk yields (kgday-1) over the six-week period were 14.8 (H) and 14.8 (Jx) for the grazing system, and 28.0(H) and 23.3 (Jx) for the confinement system. There were significant differences between thethree observation periods for time spent lying (P < 0.001), feeding (P < 0.05) and ruminating(P < 0.001), while time spent standing did not differ between observation periods. Breed hadno significant effect on any of the behaviours recorded (P > 0.05). Cows on the grazingsystem spent significantly (P < 0.001) more time grazing, than those on the confinementsystem spent eating. Cows on the confinement system spent significantly more time lying,standing and ruminating (P < 0.001) than did those on the grazing system