Their dense coat, thick skin, subcutaneous fat layers, large muscles, and digestive system which generates internal heat, ensure that these cows are well insulated.
But despite their resistance to cold, there are still some aspects that require more careful dairy cow management during winter.
Rainfall regions in South Africa
The Western Cape has a typical Mediterranean climate. Summers are hot and dry, and winters are cool to cold, with rain from May to September. Although winter temperatures are not very low – around 8 to 18°C – rain and wind can cause a drop in temperature.
Local research showed that the milk production of cows in open camps is only affected by hard, continuous rain – for example 20mm/day over four days. Shorter rainfall periods had little to no effect on milk production. Cows’ response to rain and cold varied and not all cows experienced a drop in milk production on rainy days compared to non-rainy days. Similar results were recorded in Australia.
In the summer rainfall regions, rain has a cooling effect and is not seen as too problematic. Keep in mind that rain rarely falls continuously, and cows can usually maintain their feed intake. It is only when cows ingest less feed that milk production is impaired.
How cold is cold?
In the interior of the country extreme night temperatures (lower than 3°C) occur from May to August. Average minimum temperatures in Bloemfontein are -0,2°C in June and -0,5°C in July, with a maximum temperature of around 17°C. These low minimum temperatures are still higher than the lowest thermoneutral temperature of -5°C for dairy cows.
In general cows require very little extra energy when it is cold, due to their high internal heat production. However, cows must be sheltered from wind and rain and must have a continuous supply of adequate amounts of feed due to their increased intake during cold conditions.
A dry place to rest
Regardless of when it rains, a dry and clean resting place for cows is crucial. Cows would rather lie down on concrete than in the mud. During the rain season the occurrence of mastitis increases due to wet and dirty soil conditions.
You can read up to 3 premium stories before you subscribe to Magzter GOLD
Log in, if you are already a subscriber
Get unlimited access to thousands of curated premium stories and 5,000+ magazines
READ THE ENTIRE ISSUE