Physiological Constraints to Milk Production: Factors Which Determine Nutrient Partitioning, Lactation Persistency and Mobilization of Body
نویسنده
چکیده
On a short-term basis, the efficiency of nutrient use for milk production is primarily dependent on the milk production level. As milk yield increases, a lower proportion of total feed intake is used for maintenance (a non-productive requirement that is more or less constant) of the cow. A cow producing 12 kg/d of milk is using about 50% of available nutrients for milk synthesis, whereas the corresponding value is 66% when milk yield increases to 22 kg/d.
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