Short-term grazing and urination behaviour of dairy cows differing in their genetic merit.

Breeding cows for improved production and production efficiency may have led to indirect selection for behavioural traits including grazing and urination behavioural patterns. This study investigated the relationship between genetic merit (breeding worth; BW) and grazing and urination behaviour in Holstein-Friesian × Jersey lactating dairy cows. Two groups of 12 cows were assigned into high BW (HBW; NZ$146 ± 12.8) or low BW (LBW; NZ$40 ± 11.8) groups. Cows were observed for grazing (grazing, ruminating, idling and bite rate) and urinating (frequency and duration of urination events) behaviour during the first grazing session of the day (5 h; between milking 0900–1400 h). Based on the whole grazing and urination behaviour data matrix, MANOVA and PCA procedures suggested no difference in the grazing and urination behaviour of HBW and LBW cows. Further work measuring additional traits (e.g. intake rate, bite mass, diurnal urination patterns) may be required to differentiate cows of divergent BW based on behavioural patterns. [ABSTRACT FROM AUTHOR]