As the snow flies and the cold wind blows, we often make the recommendation “more bedding please.” Of course, we have to justify the added expense — and a recent study helps us do just that.
Researchers in North Dakota measured the effects of bedding on the performance of finishing steers and growing heifers during winter. In steers, the marbling score, yield grade and feed efficiency increased dramatically with the addition of normal bedding (200 pounds of bedding/head/season) and extra bedding (400 pounds/head/season). The return on investment was more than 15-to-1, or $46 per head for a $3 investment in normal bedding.
In growing heifers, an investment of either $3 for normal bedding or $6 for extra bedding decreased daily dry matter intake from 18.1 pounds to 17.6 pounds or 16.9 pounds, respectively, while at the same time increased average daily gain from 1.94 to 2.02 and 2.04.
What about milk cows? In a study that I conducted in a large dry-lot dairy in Colorado, feed conversion efficiency was drastically influenced by weather. For each degree below 15 F wind chill, the ratio of milk-to-feed decreased by 0.008. In other words, at 0 F, a cow eating 50 pounds of dry matter would produce 69 pounds of milk instead of 75. Or, it would take an additional 4.3 pounds of dry matter to maintain a milk yield of 75 pounds.
The use of adequate bedding, meanwhile, reduces wind chill by reducing convection and conduction.
In the same study, I found that each inch of precipitation resulted in another 1 percent of the milking herd developing environmental mastitis. Again, adequate bedding can play a positive role by helping cows avoid manure contact.
Besides improving feed efficiency and reducing mastitis, bedding promotes resting behavior. When a cow is lying down, she has more blood flow to her udder — and presumably more milk production. Bedding also has been shown to decrease laminitis-associated lameness by decreasing standing time.
It takes management
Of course, bedding has to be managed. Soiled organic materials grow pathogens. The most common mastitis links to bedding type include straw and environmental streptococci, as well as wood shavings and Klebsiella.
The other aspect of bedding management that cannot be overlooked is the effect on eating behavior and nutrient intake. Good, clean corn stalks or straw are palatable and can be consumed in great quantity. When cows eat the bedding instead of the TMR, it indicates there is an effective fiber deficiency in the ration, or else animals have rumen acidosis. If milk production decreases, with an attendant increase in butterfat, following the addition of bedding, it’s time to evaluate ration formulation and feed mixing — especially if bedding disappears at a rapid rate. Healthy cows prefer to eat what’s in the bunk.
It’s especially important to consider bedding consumption in close-up animals on an anionic ration. Certain fiber sources used for bedding, such as oat straw or hay, can contain high levels of potassium. When close-up cows consume bedding — even low potassium bedding — instead of TMR, it decreases the acidifying effect of the anionic ration by dilution. Watch for milk fever and ketosis or select non-edible bedding for use with dry and close-up cows.
More bedding please
Clean, properly maintained bedding is a cost-effective management tool to improve feed efficiency and to prevent mastitis and laminitis. Talk to your veterinarian. He or she can advise you on whether you are using enough bedding.
Marquerita B. Cattell is a consulting veterinarian in Fort Collins, Colo.