colostrum

American  

[kuh-los-truhm] / kəˈlɒs trəm /

noun

1. a yellowish liquid, especially rich in immune factors, secreted by the mammary gland of female mammals a few days before and after the birth of their young.

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colostrum British  

/ kəˈlɒstrəm /

noun

1. the thin milky secretion from the nipples that precedes and follows true lactation. It consists largely of serum and white blood cells

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Other Word Forms

• colostral
  adjective

Etymology

Origin of colostrum

First recorded in 1570–80, colostrum is from the Latin word colostrum, colustrum “beestings,” colloquial for “first milk”

Example Sentences

The so-called back-to-cow movement includes products like bovine colostrum, the protein-rich milk cows produce soon after giving birth.

From BBC • Oct. 6, 2025

That milk, called the colostrum, doesn’t go to consumers.

From Slate • Dec. 4, 2024

Food and Drug Administration adds that it’s unclear as to whether or not the H5N1 viruses can be transmitted through consuming raw colostrum from infected cows.

From Los Angeles Times • Jul. 18, 2024

Sick cows have a mild illness, and produce less milk, which is thicker than usual, resembling colostrum, the first milk produced after a calf is born.

From Science Magazine • Apr. 1, 2024

Human Milk.—Between the time of birth and the beginning of lactation there is always an interval during which the breasts secrete colostrum, just as they do throughout pregnancy.

From The Prospective Mother, a Handbook for Women During Pregnancy by Slemons, J. Morris (Josiah Morris)