An encapsulated niacin product may be effective for reducing body temperature during heat stress. Niacin has been shown to help alleviate heat stress both by increasing evaporative heat loss from the body and also by reducing the effects of heat at the cell level. But unprotected niacin is extensively degraded in the rumen.
University of Arizona researchers presented a paper at last months Dairy Science Association meetings on the effect of feeding a new encapsulated niacin in heat stressed cows. The study was conducted at this time last year on a commercial herd in Arizona; a good time to study heat stress! Four hundred cows were used in the switchback study that lasted 60 days, with two 30 day periods. Cows were balanced for days in milk, milk yield and age and fed either no niacin or 12 grams/day of the encapsulated niacin.
Bottom line was that core body temperature was significantly reduced during the hottest part of the day (1:00 – 4:00 p.m.) when rumen protected niacin was included in the diet. Milk fat and milk protein were significantly higher for animals fed the protected niacin as was fat corrected milk and energy corrected milk (about 3 lbs/cow/day). The effect appeared to be greater in older cows versus first lactation animals. The trial was too short to produce any meaningful reproductive data.
No economic figures were shown relating to return on investment for the product. However, as I discussed in my last column, the effects of heat stress go far beyond just lower milk production. The lasting effect of heat stress on cow health and reproduction may be hard to put a price on, but they certainly are real. I think this product may deserve another look.
Reference: J. Dairy Sci. Vol. 91, E-Suppl. 1.
Rick Lunquist is an independent nutrition and management consultant based in Duluth, Minn. You can contact him at firstname.lastname@example.org.