Cattle manure odors are becoming a bigger issue as more urban dwellers move to rural areas. Agricultural Research Service (ARS) scientists are researching methods to reduce odors.

At the Roman L. Hruska U.S. Meat Animal Research Center in Clay Center, NE, researchers studied the diets of beef cattle, aiming to reduce odors while still raising productive animals. They found feeding high-moisture (HM) corn in lieu of the more traditional dry-rolled (DR) corn reduced odors dramatically.

Researchers are measuring compounds that cause the odors, such as starch. The more starch digestion, the less is available to cause odor, and starch in HM corn is more readily digested than that in DR corn.

In addition, HM corn is usually cheaper to feed for producers who own the corn, but can be expensive for those who don't due to transportation and storage issues.

Treating growing cattle on intensively grazed, improved pasture with anthelmintics (dewormers) for internal parasites is known to be beneficial. But, it was unknown how treatment would work on native range.

Oklahoma State University (OSU) researchers used heifers weaned in May or June to study the effect of providing supplements and/or anthelmintics to heifers on native pasture in late summer/early fall in north-central Oklahoma.

Four treatment groups were used: 1) no supplement or anthelmintic; 2) supplement but no anthelmintic; 3) anthelmintic but no supplement; and 4) supplement and anthelmintic.

Researchers used Ivermectin with clorsulon (effective against liver flukes) as the anthelmintic, applying it at the trial's start on July 26 and again on Aug. 26. The supplement was a 41% crude protein cottonseed meal, fed Mondays, Wednes-days and Fridays at 2.33 lbs./feeding until Oct. 21.

Heifers were weighed and fecal samples collected every 28 days. The 84-day weight gain for the four treatment groups was: 81 lbs., 123 lbs., 106 lbs., and 143 lbs., respectively. Researchers found supplement and anthelmintic increased gains addictively, with the greatest effects from treatment No. 4, where they were combined.

Heifers were then commingled and grazed with minimal hay and supplement for 151 days until April 24. There was little weight change during that period, with the groups averaging — in order — +20 lbs., -21 lbs., +12 lbs. and -8 lbs., respectively, bringing total weight gain, from July-April to 101 lbs., 102 lbs., 118 lbs., and 135 lbs., respectively.

Researchers found the response during late summer/early fall from the anthelmintic tended to be retained, but the benefits from supplementing tended to be lost during the following winter/spring (OSU Animal Science Res. Rpt. P-1008:18).
March 2005 Texas A&M Beef Cattle Browsing newsletter

In many production systems, producers feed cows harvested forages after calving to avoid cows in poor body condition. Costs associated with feeding these forages can make up more than half of total feed costs in maintaining a cow herd. An alternative — grazing crop residues — can decrease feed costs.

The University of Nebraska conducted a three-year study to evaluate the resource inputs, animal performance and carcass characteristics of the two production systems.

The control group (CON) grazed pasture and was fed hay for the winter, and steers were finished in a feedlot 211 days after weaning.

In the treatment group (TRT), cows grazed pasture and crop residue during the winter and were fed hay. TRT steer calves grazed crop residue after weaning, grazed pasture in the spring/summer and were finished in the feedlot for 90 days.

Researchers found body condition scores, after TRT cows returned to pasture after grazing residues, were greater for CON than TRT cows. Calving rates were similar for both groups, with CON calving at 91% and TRT calving at 93%.

Researchers determined that differences in cow body weight and condition after grazing cornstalks didn't affect calving or weaning weights.

In the feedlot, CON steers had lower average daily gain and dry matter intake, but were more efficient than TRT steers. TRT steers had greater final and hot-carcass weights and decreased marbling scores. Cost per weaned calf and weaning breakeven were greater for CON calves than TRT calves.

In evaluating economics of the total system, researchers found a greater profit potential in the TRT system when steers were priced into the system on either a financial or economic basis and when steers were sold on a live basis. No differences were observed when steers were sold on a grid basis. (R.V. Anderson, et al. J. Anim. Sci. 83:694)