The drinking behaviour of dairy cows in late lactation

Abstract

The drinking behaviour of grazing cows was investigated in two studies with the purpose of determining the suitability of using water intake as a motivator for voluntary movement of cows within a pasture-based automatic milking system (AMS). In the first study 100 mixed-age Jersey cows in late lactation were observed for 48 h. Cows drank on average 2.4 times/24 h (range: 1-6) and usually alone or with one or two other animals. Although every cow drank at least twice during the 48 h, 31% of cows recorded an interval between drinks > 24 h. Less than 1% of drinking occurred between 2000 h and 0700 h. The second study compared the drinking behaviour of Overseas (OS) and New Zealand (NZ) Holstein Friesian cows that were either grazing pasture (GRASS) or fed a Total Mixed Ration (TMR). TMR cows drank more often (5.2 times/24 h) than GRASS cows (3.5 times/24 h, P < 0.001). Feed type altered the distribution of drinking with 76.8 % of TMR cows drinking between 2000 h and 0700 h compared with only 24.5% for GRASS. Water intake was also higher for TMR (73.0 L/cow/day) compared with GRASS (53.7 L/cow/day) animals. The studies showed that the individual nature of drinking behaviour would be aligned with the AMS objectives of distributed rather than batch milking. However, the small number of cows drinking during darkness when grazing indicates that water intake would need to be used in combination with other motivators to ensure a continuous flow of cows to the dairy.