- Management of nutrition can be as important as nutritional composition in ensuring cow health, welfare, production, and efficiency
- Good health, efficiency, production, and longevity is maintained by utilizing feeding management strategies that promote dairy cows to consume frequent, small meals throughout the day, discourage extensive sorting of feed, and encourage cows to remain standing after milking
- Cows need good access to the ration that is formulated for them throughout the day. Good access to clean and palatable water is just as important.
- Good feed access can be achieved through frequent delivery of feed close to the time of milking, frequent feed push-up, and ensuring cows have sufficient space at the feed bunk
Past research in dairy cattle nutritional management has focused almost exclusively on the nutritive aspects of the diet, resulting in many discoveries and improvements in dairy cow health and production. Despite many advances this field we are still faced with several challenges associated with feeding dairy cattle. Recent field observations suggest that housing and management can play as large of a role as nutrition in the performance of dairy cows. For example, Bach et al. (2008) found in a cross-sectional study of 47 herds, fed the exact same ration, that 56% of the variation in observed milk production between herds was explained by non-dietary factors (e.g. presence or absence of feed refusals, free stall stocking density, and whether feed was pushed up in the feed bunk). Similarly, recent cross-sectional studies have shown that production is associated with various housing and feeding management factors for cow milked in parlours (Sova et al., 2013) and robotic milking systems (Deming et al., 2013).
This paper will help shed light on such findings by describing the impact of feeding management on dairy cow behaviour, health, and productivity. To that end, the importance of dairy cow behaviour will be emphasized, including how dairy cows eat, when they eat, and what they actually consume. The paper will then describe how we can use that knowledge to evaluate housing and feeding management strategies. In particular, empirical evidence will be presented on how dairy cattle need to be provided good access to, and enough, feed at the right times and frequency to ensure they can meet their requirements, satisfy their natural feeding behaviour patterns, and consume their feed in a healthy manner.
Importance of feeding behaviour
How do cows eat?
Under natural grazing conditions dairy cattle will engage in foraging behaviour from anywhere from 4 to 9 hours per day (Hafez and Bouissou, 1975). This feeding time would be split into a number of smaller meals occurring throughout the day, with the largest meals occurring in the early morning and late afternoon. Modern, intensively-housed dairy cattle fed a conserved ration typically consume their daily dry matter intake in up to 6 hours per day, spread between 7 or more meals per day (DeVries et al., 2003). Management practices that cause adult dairy cattle to eat fewer and larger meals more quickly have been associated with an increased incidence of sub-acute ruminal acidosis (Krause and Oetzel, 2006). The reason for this risk is that ruminal pH declines following meals, and the rate of pH decline increases as meal size increases and as dietary effective fiber concentration decreases (Allen, 1997). Further, as cows spend less overall time feeding, and increase their rate of feed consumption, daily salivary secretion is reduced (Beauchemin et al., 2008), decreasing the buffering capacity of the rumen and reducing rumen pH. Alternatively, when cows slow down their rate of dry matter (DM) consumption, and have more frequent, smaller meals, throughout the day, rumen buffering is maximized, large within-day depressions in pH are avoided, and the risk of sub-acute ruminal acidosis is decreased. Thus, to maximize rumen health, efficiency and productivity, it is important to utilize feeding management strategies that promote the frequent consumption of feed in small meals throughout the day.
When do cows eat?