Concentrate feeding

Importance of Roughages in Cow Feeding

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Cow Feeding 

There are a few myths about cow feeding or concentrate feeding that have influenced farm practices for decades:

  • The commercially available concentrate feeding is better for cows
  • Feeding concentrate on cows helps increase the content of fat in milk
  • Feed mixture prepared at the farm with cakes and chuni is better and cheaper than commercial feed
  • Concentrate feeding is better than feeding grasses and fodder
  • If the cow eats the feed fast, it means the feed is of a better quality
  • The feed should be soaked in water overnight and then fed to cows, as this improves digestion
  • Cows should be fed twice a day and offered water after feeding.

Unfortunately, most of these are untrue and are in fact harmful to the animal. 

Cows are ruminants and their natural feed is grass and fodder; collectively called roughages. Concentrate feeding is required only when the roughage quality is very poor and unable to provide adequate energy. When the animal produces large quantities of milk, it requires a larger amount of energy a requirement that cannot be met by low energy density roughages. Concentrate feeding also increases the overall cost of milk production. Farmers must understand that the first basic principle of feeding in cows is to feed as much roughage as possible to meet the dry matter requirement, and that concentrate is to be fed only when it is required as a supplement.

Concentrate feeding is not entirely harmless to cows, as these produce acid in the rumen and cause acidosis. An absence of good quality roughage in feed can run the risk of lowering the level of milk fat, contrary to the belief that concentrate feeding enhances milk fat.

A good feed for cows is the one that stimulates good mastication and rumination. Both of these depend on the particle size of feed, especially fodder. Feed particles that are less than 0.5 inches can significantly hinder rumination, and consequently digestibility. Grass or fodder chaffed to 1 or 1.5 inches stimulates rumination by facilitating the formation of a mat that eases the process of microbial digestion. It is also not a bad idea to feed around one kilo of long-staple grass for better mat formation.

Many farmers soak concentrate feed in water for a few hours or even through the night. This is actually a hindrance to microbial digestion, and can even lead to bacterial growth on the feed that causes it to spoil. In states like Assam and Rajasthan concentrate feed is roasted overnight.  Soaking cakes like cottonseed just to mince and mix in the feed is alright, but soaking the feed-in water for even a few hours is not at all advisable.

The golden rule in ruminant feeding is that there shouldn’t be frequent variations in feed components, and the feed should remain the same throughout the year. The feed should comprise mainly of good quality roughage. You can usually tell that roughage is of good quality when the animal voluntarily consumes it in large quantities. When the cow is given a mixture of high and poor energy roughages, it will sort and choose only the good quality feed. Chemically speaking, good quality roughages should have good digestible nutrients and high energy value.  Green fodder harvested at the right time with a moisture content of around 60 – 65% has good palatability. A general rule is that once the grains are harvested from a plant, the leftovers are of a low quality. Provided they are harvested at the right age, varieties cultivated specifically for fodder use will have much better energy content.

Another important point to remember is that fodder quality will vary with time. When you harvest fodder on a daily basis it is labour and time-intensive, and the quality will vary. For example, when fodder is immature, its water content is higher, but so is the energy and digestible nutrient value. As the fodder matures its moisture content goes down, the total nutrient content as dry matter increases but the energy goes down. A good strategy would be to harvest fodder crops during the best age window and preserve it for later use. This also reduces the dependence on daily labour needs. 

Roughage is beneficial in a number of ways. Firstly, it stimulates the muscles in the wall of the rumen to contract and expand, which stirs up the material in the rumen. This is called rumen motility. If you put your hand on the left abdomen fossa you can feel this churning. Rumen should stir up once every 90 seconds or twice in 3 minutes. The rumen stirring action should be strong enough when you press the left lumbar depression as shown in the image. This agitation in the rumen helps the slurry inside to mix so that microorganisms can completely break it down. Another effect of roughages is to activate the chewing of cud after regurgitation. Without quality roughage in their feed, cows are unable to ruminate well.

Dr. Abdul Samad

Ex-Dean and Director, MAFSU, Nagpur