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Milk Composition & Synthesis
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Milk Composition
Stage of Milk Removal

Variation in Milk Composition During a Milking

Even during a milk removal or milking, the composition of milk can vary. Milk fat in the cow provides an example, as indicated in the graph below. Milk fat is lowest in the fore-milk and gradually increases in percentage as the milk is removed. The last milk out of the gland is highest in milk fat content. Somatic cell count (SCC; leukocyte concentration in milk) of milk removed from the gland follows a similar pattern, with the lowest SCC found in the fore-milk (except for the very first few streams of milk removed from the teat) and the highest SCC in the last milk removed from the gland. It is important when taking milk samples from a cow for testing of milk fat and other component that a well mixed sample is taken representing the entire milk collected during a milking.

Question: If you were asked to collect a representative milk sample from a cow, how would you go about doing that?

Question: If you were to use the California Mastitis Test, which is based on the SCC of the milk used in the test, and you sampled the milk just after the cow was milked, how would those results compare with a sampling taken shortly before she was milked?

During a Milking
Milk Composition & Synthesis