Calves that are chilled at birth, without immediate assistance to warm/dry them and make sure they ingest colostrum in a timely manner, have poor survival rates. If a calf's mouth gets cold before he suckles, he may not be able to get the teat in his mouth and suck, and therefore does not obtain crucial energy (for keeping warm) and the antibodies he needs – to protect him against disease. Also, his ability to absorb the antibodies from colostrum diminishes as he becomes colder.
As stated by Dr. Robert Callan, Colorado State University, calves born in cold weather may suffer adverse effects if they don't get right up and nurse before they chill.
“The first thing to understand about body temperature in newborn calves is that they start out with a high temperature, about 103 degrees F,” says Callan. “After they're born it starts to drop and is down to 101.5 or 102 within a few hours (which is normal temperature for cattle). But if weather is cold and it drops below 100, this means the calf is not able to thermo-regulate and keep himself warm.
“A normal, healthy calf has a tremendous ability to thermo-regulate, especially if the cow licks him off quickly and helps dry him.”
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