Colostrum is the first milk the dam produces immediately after birth: a yellowish milk, rich in protein. Its job is not nutrition alone — it is the route by which protection passes from mother to newborn. A newborn that misses colostrum stays exposed to diseases that will later be treated with drugs, so what is saved in the first hours is paid back many times over in the weeks that follow.
Three conditions, not one
The Terrestrial Animal Health Code of the World Organisation for Animal Health states that whether a calf receives adequate immunity from colostrum generally depends on three things together: the volume of colostrum ingested, its quality, and how soon after birth the calf receives it. A shortfall in any one of the three undermines the whole result: a large volume of poor colostrum does not do the job, and neither does excellent colostrum given too late.
- Volume — that the newborn drinks a sufficient amount, not a few sips.
- Quality — genuine colostrum from the first milking, not diluted or later milk.
- Timing — the one condition that no later quantity can make up for.
The window: twenty-four hours, and the first six are the most valuable
The World Organisation for Animal Health recommends that a calf receive colostrum of satisfactory quality within 24 hours of birth and in sufficient quantity to provide passive immunity, and adds that colostrum is most beneficial if received during the first six hours after birth. So this is not a single "first day" deadline but a gradient: the earlier you are, the greater the benefit.
Lost time cannot be made up with volume
The common mistake is to put it off until the evening and then compensate with a large amount. A late feed nourishes the newborn, but it does not give it the protection it would have taken in the first hours. If the dam cannot nurse straight away, because of a difficult birth or weakness, milk her by hand and give the colostrum by bottle rather than waiting.
For how many days should colostrum continue?
The FAO primary animal health care manual advises leaving the calf to take colostrum for at least four days after birth, and leaving the colostrum for the newborn rather than for the household's food, even where it is customary to eat it. For an orphan with no dam, the manual advises providing colostrum for four days or eight feedings if possible, collected from other mothers into a clean bottle.
The same manual notes one small practical detail that ruins colostrum if ignored: do not boil it, because boiling makes it curdle.
Which dam should it come from?
The World Organisation for Animal Health states that where there is a risk of disease transfer from the dam, colostrum from a healthy cow should be used instead. This point is often overlooked: colostrum is a route for protection and a route for infection at the same time, and a sick dam may pass both to her newborn together.
What has this to do with antibiotics?
The connection is not pharmacological but arithmetical. The Terrestrial Animal Health Code and the Codex Alimentarius code of practice both hold that good management and disease prevention reduce the need to use antimicrobials. Colostrum is among the cheapest preventive measures there is: it requires no purchase, no equipment, and no prescription — only attention in the first hours. And every calf that does not fall ill is a course of treatment never given.
What to do right after birth
Clear the mucus from the nose and mouth and check that breathing is normal, then let the newborn suckle as soon as possible. If it does not soon suckle on its own, do not wait "until it gets hungry", because the first six hours are the most valuable: milk the dam and give it the colostrum by bottle, and record the time of the first feed just as you record the date of birth.
The strongest way to lower antibiotic consumption is to lower the need for it. That article explains the rest.
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