01/24/2026
How cold is too cold for a newborn calf?
The fact is, that there are so many factors to consider. It would be so easy if you could just say -10°C or -15°C is the minimum temperature that a newborn calf can normally deal with. But the fact is, it isn't that simple. In perfect conditions, if everything goes right most calves can handle -10 to -15°C. But perfect conditions are very rare.
Climatic Considerations
‼ Actual temperature
► 0°C is 32 °F
► -10°C is 14°F
► -18°C is 0°F
Let's consider that, before the calf is delivered it is kept in a very temperature controlled and WARM environment. When it is born, it is WET. Look up hypothermia and look up how being wet will speed up the hypothermia process.
‼ Precipitation
Rain is worse than snow. If they can’t get dry, they can’t get warm.
‼ WINDCHILL
Add wind to cold and wet. It doesn't take a lot of wind to quickly chill a wet calf.
https://www.wpc.ncep.noaa.gov/html/windchillbody_txt.html
‼ Humidity.
Just like humidity can make the temperature feel warmer, it can also make the temperature feel colder.
Management Considerations.
‼ Facilities
Amount of bedding, amount of windbreak, indoors or outdoors. The cow’s choice of calving spot… Even if we have great windbreak and bedding, she has to choose to use it. I’ve seen enough cows choose a snowbank or a hilltop over great bedding and windbreak.
‼ BW of the calf
Smaller calves chill quicker than bigger calves, it is a simple fact that a smaller body mass chills quicker than a larger one. Bigger calves likely have more fat on them than smaller calves as well. Also, consider calving ease, calves that have a hard birth or that are stressed may be slower to get going which will result in them getting chilled quicker. There has to be a balance obviously.
‼ Nutritional status of the dam
Cows in good body condition, that have been provided with adequate nutrition and have good mineral status will have healthier and stronger calves. Thin cows/heifers or ones that have had less than ideal nutrition are more likely to have weaker calves.
https://www.agproud.com/articles/52997-brown-fat-ensures-survival-in-calves
‼ Age of dam
Older cows are better mothers and quicker to clean their calf up than first calf heifers because they have done it before. OLD cows may have issues due to arthritis, weakness and lack of energy.
While a calf MAY be able to survive, it doesn’t mean that they should have to. Saying that “My calves survive being born outside in -10 or -20 temperatures” really isn’t something to be proud of. There are many things we should and can be proud of in our operations. I don’t think that saying that we leave our newborn calves to be born out in inclement weather and they SURVIVED is one of them. I am not talking about the odd surprise or missed calf when we are trying our best or the spring storm that rolls through at the worst time and farmers/ranchers are out doing their absolute best to manage it, but the ones that are routinely left to fend for themselves.
♥You don’t have to like what I say, but if you wish to calve when it is cold out you need to have the proper facilities, otherwise, choose a better time of the year.♥
In our operation, -10°C (14°) is the temperature we go by, it can vary a little depending on conditions. And that depends on morning or night. If it’s later than mid afternoon, calves go in the barn. If its morning or early afternoon, we evaluate them individually. It’s a simple fact that in the morning the temperature is likely to get warmer, if it is late afternoon, it is likely to get colder.
So, -10°C is the minimum temperature for a calf to be born and left outside. But there are many other factors that come into consideration. Windchill, precipitation, where she is choosing to calve (on the straw in the windbreak or in a snowbank or on a hilltop, etc.). Wind and precipitation are the two biggest factors, even more so than temperature. Because they cause the temperature to be colder than what the thermometer says. There are times when the temperature is ABOVE freezing and it is still too cold for the calf to be born out in the elements.
►Rain is one of the worst things that can happen to a newborn calf.
►It doesn’t take a high wind to chill a calf quickly
►Location, location, location. In the corner of the windbreak that is well bedded vs the top of a hill or a snowbank. And while you think you can maybe move her to the windbreak, it’s usually a futile effort as she has chosen her spot and if there is a way she can get back to that spot, she will.
