EFFECTS OF DRINKING-WATER FLOW-RATES AND SOCIAL RANK ON PERFORMANCE AND DRINKING BEHAVIOR OF TIED-UP DAIRY-COWS

The effect of 3 different water flow rates into the water-bowls (2, 7 and 12 l/min) on water intake, drinking behavior, feed consumption, milk yield, live weight and physiological parameters was studied in 2 experiments, with 9 and 12 tied-up dairy cows, respectively, of the Swedish Red and White breed. In the 1st experiment (1 C) each cow had its own water-bowl; in the 2nd experiment (2 C) 2 cows shared the same water-bowl. The dominant cow within each pair was determined (2 C). The higher flow rates led to a significant (P < 0.05) increase in water intake in both experiments. Daily drinking frequency was highest (P < 0.01) at the lowest flow rate (40 vs. 28 and 30). Time per drinking was also longest (P < 0.01) for 2 l/min; the 2 other flow rates did not differ significantly. Amounts of water consumed per drinking were 2.4, 3.5 and 3.4 l (NS [no significance]). No significant effects of treatment on feed consumption, milk yield, live weight or physiological parameters could be detected. Dominant cows consumed significantly more water and hay than the submissive cows. Milk yield was also significantly higher for the dominant cows, 21.3 vs. 20.2 kg 4% fat-corrected milk (P < 0.05).