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.

Posted by Acres Admin on Aug 7 2012. You can follow any responses to this entry through the RSS Feed. Both comments and pings are currently closed.