Unfortunately, just because great rations may be put together on-farm, it does not mean cows will necessarily eat those rations in the amount required or in a manner that promotes good health, production and efficiency.
These problems may be directly related to the way cows eat their feed. One of the things we often forget is that the way a cow eats will dictate how much feed she consumes. For a cow to eat more, she needs to alter some aspect of her eating behaviour.
For example, she needs to spend more time eating, eat faster or a combination of those two things. Similarly, she needs to have more frequent meals, larger meals or (again) some combination of those.
In recent research, we have shown that greater feed intake, as well as milk production, are more consistently associated with cows spending more time at the bunk, consuming their feed in more frequent, smaller meals (as opposed to eating larger, faster meals).
This type of eating pattern is not only good for production but also for rumen health and efficiency. We know that cows who consume their feed in smaller, slower, more frequent meals also have a more stable rumen environment; this further translates into improved fibre digestibility and improved milkfat content.
Another important aspect to consider is how variable feed consumption is across the day in terms of what actually gets consumed. We know that even with our best TMR, cows will sort their feed.
That sorting will result in greater variability across the day in terms of what cows eat, both within themselves as well as between individuals within the herd. For robotic milking dairies, there is another reason why eating patterns of dairy cows are important: Eating behaviour is often tied to milking activity.
While we do not have any direct evidence to suggest that milking cows necessarily stimulates eating activity, we do know much eating activity occurs in and around the time of milking.
With cows milking across the day in robotic systems, it stands to reason that it is then important to provide and stimulate eating opportunities for cows across the day.
This may have several benefits, including stimulating eating activity after milking, which helps keep cows on their feet and reduces the risk of mastitis, but also may actually help distribute milkings more evenly across the day, thus utilizing the time of the robotic unit more efficiently across the day and night.
The simplest way of achieving all of this is to make sure cows not only have good access to feed whenever they want to but also are stimulated to access their feed at various time points across the day.
We have demonstrated in several studies that the most consistent and effective way to stimulate feeding activity is to provide new feed – an activity which creates much more of a feeding response than does the time of day, milking or pushing up feed.
Thus, it stands to reason that producers should aim to deliver feed as often as feasible across the day. Our research has demonstrated that this will create those favourable eating patterns described above as well as reduce the extent of feed sorting.
With much advent in the development of automated TMR mixing and delivery systems, delivering feed frequently throughout the day is becoming much more achievable on many farms.
The next most important thing, in between feed deliveries, is to ensure cows always have access to feed in the bunk. This is where feed push-up becomes important; pushing up feed frequently will ensure that, regardless of the reason the cow is at the bunk, there is feed available to her and in reach. Using automated feed pushers may be key in ensuring this.
A tell-tale sign of a farm that does not push up feed often enough is one where the cows come running to the bunk once the feed is pushed up. This indicates cows have gone too long without feed available to them.
This type of response may also be an issue on farms that feed for very little to no refusals. If cows are without feed at the bunk for any extended period of time, they will, upon the next feed delivery, consume their feed too fast in much too large of a meal.
A final factor that is going to influence feeding activity is the level of competition for resources in the pen, including feeding and lying space. When we overcrowd pens of cows, they alter their behavioural patterns. This includes reduced lying time in response to overcrowding freestalls.
Too little feedbunk space will result in cows changing their intake patterns, consuming larger, faster meals or altering their patterns of intake whereby they may forgo eating opportunities at times of the day when they are motivated to do so.
This has the potential to reduce feed intake; further, in robotic milking barns it may then also cause cows to forgo a milking event – which may reduce production. This type of response explains why in recent research on robotic dairies in Canada we have seen greater needs to fetch cows in herds with higher stocking densities.
In summary, production is optimized when cows always have feed in front of them, can access feed when they want to and are stimulated at multiple time points across the day to access that feed.
For robotic dairies, that is not only going to ensure sufficient intake, but also help stimulate milking events, as well as help spread out those milkings across the day. 
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Trevor DeVries
- Associate Professor
- University of Guelph
- Email Trevor DeVries
