Heat stress and Hydration of Livestock
We are dealing with some extraordinary weather this year and with that high temperatures and dry conditions affect us all and it also takes a toll on our livestock. High temperatures raise the incidents of heat stress in livestock, especially when coupled with dry conditions and high humidity. When animals are going through times of hot and high humidity weather, it can:
• reduce breeding efficiency
• reduce milk production
• reduce feed intake which reduces weight gains and sometimes cause death
Livestock should be checked frequently and measures should be taken when hot and humid weather is forecasted. To improve conditions to reduce stress on the animals and to keep them healthy is to:
• provide shade, either by trees, buildings or sunshades
• improve ventilation
• have sufficient water available
• spraying down the livestock or even spraying roofs where the animals are housed to reduce temperatures
During periods of high temperatures, it is a must to have a source of cool, clean drinking water is essential to help keep animal’s internal body temperature within normal limits. When temperatures increases from 70oF to 95oF can increase total water requirements by about 2.5 times.
Increased water consumption will increase excretion of urine. This will also increase the loss of certain minerals, such as sodium (a part of salt), potassium, and magnesium. Free choice trace mineral salt or a free choice mineral should be provided in a location that the animals will consume it. Loose salt will be more readily consumed than block salt.
Heat stress occurs when cows cannot dissipate enough heat to maintain their core temperature below 101.3 °F. Internal heat production increases at higher dry matter intakes which make high producing cows more sensitive to heat stress. Body temperature increases of just 2.7 °F have been shown to result in intake reductions of almost 13 pounds.
Recommendations to help reduce stress in dairy or beef cattle even further:
• Feed early in the morning (5 — 6 a.m.) or evenings to avoid the highest metabolic heat production (rumen fermentation) coincide with maximum environmental temperatures.
• Avoid feed shortages in the feed bunk. When offering fresh feed there will be a little refusal, remove refusals at least once a day to minimize heating of the fresh feed.
• Feeding a TMR is better than supplying feedstuffs individually (component feed).
• High moisture forages (e.g. silages) improve ration acceptability. In addition, as fermented feeds have lower pH they slowdown mold and yeast growth in the ration and reduce heating. Mold and yeast growth oftentimes result in compounds with unpleasant odor and taste for cattle.
• The inclusion of other high-moisture products such as sweet bran, beet pulp or wet distillers grains also helps increase ration acceptability.
• Add water when the Dry Matter of the diet exceeds 60% to bring it down to 50%. Water addition conditions the ration, reduces the dust, and increases its acceptability.
In times of high heat, take care of yourself and be prepared to help keep your animals cool, water refreshed and stress free so we all can make it through these times of temperature spikes.