I don’t want to buy an expensive solution to take core body temperature to gauge heat stress. How can I tell what my cows CBT is without spending tons of money?

Many milking machines take milk temperature; this is a great way to tell when your cows are heat stressed. Milk temp is the same temp as CBT(Core Body Temperature). If the milk temperature is above 102.8°F/39.3°C your cow is heat stressed.

Monitor your milk temperature. When cows are heat stressed, the milk temp rises because her body temperature increases, which is an indicator that your cow is heat stress. 
This is a very inexpensive indicator of heat stress, and it gives you immediate results. Monitoring milk temp takes the guesswork out of knowing if heat stress is affecting your cows. 

According to OMAFRA (article link below)

"Dairy cattle have a normal body core temperature of 101.3 to 102.8 degrees F (38.5 to 39.3 degrees C). The thermoneutral, or comfort, zone for cows is an environmental temperature range of 41 to 77 degrees F (5 to 25 degrees C). Within this zone, the heat produced by their normal bodily functions approximately equals the heat lost by their bodies.

Environmental heat comes from solar radiation and hot weather. High humidity and lack of air movement in barns or holding areas aggravate the problem. Three temperature-humidity ranges play a significant part in heat stress:

  • Temperature of 100 degrees F (38 degrees C) and 20 per cent humidity. You need to begin serious measures to alleviate heat stress.
  • Temperature of 100 degrees F and 50 per cent humidity. This is a danger zone for cattle and you should implement immediate steps to address the problem.
  • Temperature of 100 degrees F and 80 per cent humidity. This is lethal for cattle.

See the heat stress chart above to assess the level of heat stress according to the temperature and humidity index. 

"Heat stress is one of the major concerns which affect the production potential of dairy cattle almost in every part of world. Elevated temperature and humidity negatively affects feed intake leading to negatively affecting the reproductive potential which ultimately decrease milk production. High yielding cows more susceptible to heat stress than the low yielders. Heat stress can increase body temperature which may affect the fat synthesis in mammary gland. Apart from reducing the milk production, heat stress can also reduce the quality of milk. Internal metabolic heat production during lactation can further reduce the resistance of cattle to high ambient temperature, resulting in altered milk composition and reduction in milk yield. Heat stress can affect the various components of milk such as fat (%), solid-non-fat, protein, casein and lactose content. Heat stress can increase the somatic cell count indicating the reduction in quality of milk produced. Further, heat stress can also cause endocrine disbalance such as altering the levels of prolactin, thyroid hormones, glucocorticoid, growth hormone, estrogen, progesterone and oxytocin which ultimately affects the milk production. Heat stress through higher udder temperature may also cause mastitis in dairy cows. In addition, heat stress during dry period in particular might trigger mammary gland involution accompanied with apoptosis and autophagy, decreased amount of mammary epithelial cells can ultimately cause decline in milk yield. It may be concluded from this review that heat stress is considered to be adversely impacting both quantity as well as quality of milk produced. Heat stress brings about these impacts through reduced feed intake, altered hormone concentration and pathological changes in udder during mastitis."

According to Dairy Journal (article link below)

CowKuhlerZ offers a solution to heat stress. Maintaining core body temperature and keeping cows within their thermal comfort zone. How? By continually monitoring the temperature-humidity index in your barn and adjusting itself accordingly. A combination of a powerful, focused airstream, a timed ultra-fine droplet and an intelligent controller work together to keep your cows comfortable and cool all year long.


For more information on how CowKuhlerZ prevents the effects of heat stress fill in the contact form below or call 1-844-GET-KUHL 


Link to OMAFRA article


Link to Dairy Journal article