Nutrient requirements of the lactating dairy cow

The nutrient requirements of the dairy cow for milk production depend upon the amount of milk being produced and its composition. 

The yield of milk is decided primarily by the breed of the cow. Generally speaking, the order of yield for the main British dairy breeds is Holstein, Friesian, Ayrshire, Guernsey and Jersey (Table 16.4). 

As a result of these factors, the yield of milk may vary over a very wide range. Fortunately, such variations present fittle difficulty in assessing the nutrient requirements of the cow, since yield is easily and conveniently measured. 

When estimates of yield are necessary for the long-term planning of the feeding of the lactating cow, several useful generafisations may be made that allow prediction of yield at a given stage of lactation. Thus, peak yield may be calculated as one 

Adapted from National Milk Records Production Annual Report 2008. 

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