Good winter administration practices contribute to wholesome cattle, cheap feed prices and long-term productiveness of the meat cow herd. There can be instances through the winter when it will likely be essential to regulate the ration to assist cows by way of chilly circumstances.
When does a cow start to really feel chilly stress? Chilly stress, outlined as decrease vital temperature, is the temperature beneath which a resting animal should enhance its metabolic price to remain heat. The precise air temperature when this happens varies relying largely on the quantity of insulation the animal has. Thickness of the hair coat and whether or not the hair is dry, moist and/or matted are main influencers.
Listed here are decrease vital temperatures primarily based on coat situation and assuming no wind chill:
- Moist or summer season coat, 59 levels F
- Dry fall coat, 45 levels F
- Dry winter coat, 32 levels F
- Dry heavy winter coat, 18 levels F
Wind chill should be included when figuring out what number of levels beneath a cow’s vital temperature level to estimate the severity of chilly stress. For instance, a 10-mile-per-hour wind at 20 levels has the identical impact as a temperature of 9 levels with no wind. Situations the place the cattle have moist hides or can’t get out of the wind end in chilly stress. Subcutaneous fats thickness is one other contributing issue.
Greater vitality necessities
Cattle will voluntarily eat extra feed to fulfill the added vitality necessities wanted to remain heat when temperatures are beneath the decrease vital temperature. This could vary from a 2% to 25% enhance in voluntary consumption to fulfill their vitality wants. Consumption throughout excessive chilly and blizzards can fluctuate vastly. Barometric strain adjustments and lack of shelter from the wind the place the feed is situated can affect consumption.
Power wants of cattle enhance about 1% for each diploma F beneath the decrease vital temperature. Realizing forage high quality is vital to realizing what the choices are for offering the additional wanted vitality to assist cattle cope with chilly stress. The forage’s impartial detergent fiber content material determines how a lot the cow can eat. On the whole, cows can eat 1.1% of their physique weight of NDF. It will fluctuate barely primarily based on the digestibility of the NDF. It’s doable that cattle might not have the ability to meet their vitality wants in climate circumstances beneath their decrease vital temperature with some lower-quality forages that may meet their wants in milder circumstances.
Supplementing cattle with further corn is a standard technique to offer further vitality. Some beef producers can present further vitality wants by feeding higher-quality forages (decrease NDF) throughout colder climate. Realizing the standard evaluation of accessible feed sources helps economically and effectively match sources to wants for every state of affairs.
Be sure that all animals have entry to supplemented feeds to forestall bossy cows from consuming greater than their share and timid cows not getting any. Present at the least 30 inches per head of bunk house. Another choice is to divide cattle into related teams of fewer head primarily based on weight, age and physique situation to offer much less competitors or extra even competitors throughout the group.
Keep in mind that cattle can adapt to short-term climate adjustments comparatively effectively with no vital affect on efficiency. Cows in good winter situation with dry, clear hair coats and wind shelter can cope with a couple of chilly, depressing days with out struggling long-term results. Nonetheless, ignoring the vitality prices of long-term chilly stress vastly will increase the chance of issues down the street throughout calving and subsequent rebreeding efficiency.Â
Halfman is the meat outreach specialist for College of Wisconsin Extension. This column is supplied by the UWÂ Division of Extension Livestock Group.
