The influence of low temperature on dairy cows
The low temperature below the thermal neutrality zone influences the comfort, health and production of dairy cows. The thermal comfort in the dairy cow depends on age, breed, feed intake, production, housing conditions, body fat deposits, skin condition and animal behavior. The function of thermoregulation becomes functional after the disappearance of the blood fructose, respectively after 6 days in calves.
The effect of the low temperature on the metabolic and physiological adaptation for dairy cows is identified by: increased consumption of dry matter, increased frequency of rumination, increased motility of the gastrointestinal tract, increases basal metabolic rate and energy requirement for the maintenance of vital functions, consumption of body oxygen, increases heart rate, increases adrenaline, cortisol and growth hormones, lipolysis, glycogenogenesis, glycogenolysis, increases production of liver glycogen. At the level of the body, peripheral vasoconstriction occurs, the reduction of heat loss through sweating and the increase of thermogenesis.
In the Holstein-Frisien breed, milk production remains constant in the range -10 … 12°C, while in Jersey breed the production gradually decreases to below + 5°C (explained by the low body weight).
In order to alleviate cold stress, the following are recommended: measures to prevent the freezing of water and water storage tanks, increasing the amount of feed, especially high-energy feed, preventing the increase of humidity inside the shelter, keeping the udder dry by using dry bedding.