As ethanol production expands in the Midwest, the availability of ethanol co-products also increases. Ethanol co-products' high protein and energy content make them ideal as animal feed, particularly in confinement feeding situations.
Kansas State University researchers recently examined co-products' potential in growing diets for cattle. They studied dried distillers grains from either corn or grain sorghum to see if they were interchangeable in a 20% crude protein (CP) supplement used in a management system for growing cattle grazing low- to medium-quality forage.
Dividing crossbred beef replacement heifers into three groups, each was fed 6 lbs./heifer/day of supplements containing 20% CP. The three supplements compared were: 1) 50% cracked corn, 25% soybean meal and 25% ground grain sorghum; 2) 50% cracked corn and 50% corn distillers grains with solubles; and 3) 50% cracked corn, 31% sorghum distillers grains with solubles and 19% ground grain sorghum. Heifers grazed common native-grass pasture and had free-choice access to smooth brome hay in round bale feeders.
Researchers noted no differences in heifer weight gains and average daily gains among the treatments. Heifers on corn-dried distillers grains had a slight gain advantage early in the trial, which was interesting because its digestibility is less. Researchers believe the difference is explained by the higher fat content of corn dried distillers.
Total diet intake was similar among all treatments, but dry matter intake as a percentage of body weight was significantly greater for heifers on the soybean meal treatment. The difference in intake may be due to the greater degradable intake protein content of soybean meal.
Researchers concluded the co-products of ethanol production — either corn or grain sorghum — can be interchanged in a 20% CP supplement in a management system for growing cattle grazing medium- to low-quality forage.
— K.W. Harboroth, et al., Kansas State University 2006 Beef Cattle Research.
To help reduce common pathogens in ground beef and other meat products — by up to 99% — scientists are looking to introduce a harmless bacteria to the products. The bacterial mixture contains four strains of lactic acid bacteria (LAB), commonly used in such cultured dairy products as yogurt and cheese.
LAB progressively reduces the levels of E. coli O157:H7 and Salmonella in ground beef during several days of cold storage.
Clearing the way for commercial use, the Food and Drug Administration (FDA) has classified the practice as “generally regarded as safe.” A team led by Texas Tech University researcher Mindy Brashears developed and tested the LAB mixture.
The team used four strains of Lactobacillus acidophilus. Studying each strain separately, they found the E. coli incidence was reduced by 90% after eight days, and Salmonella reduced to similar levels after four days in cold storage.
But, eight days is considered too long to store raw ground beef without freezing it, so the team mixed all four strains and tested it in contaminated ground beef samples. The mixture yielded a 99% reduction of E. coli after three days of storage and a 99.9% reduction after five days.
Salmonella was reduced more than 99.9% after three days, and undetectable after five days.
“These LAB are unique in that they eliminate the pathogen at refrigeration temperatures, but don't grow during refrigerated storage,” according to their research in the Journal of Food Protection. “Growth of LAB in a fresh meat product would not be desirable because it would lead to premature spoilage of the product.”
The researchers also examined if ground beef taste would be affected by the LAB mixture. A taste panel couldn't detect a difference between treated and untreated samples stored three days before cooking.
Researchers haven't been able to pinpoint exactly how LAB combat E. coli and Salmonella. Some studies “have indicated that a protein-based product, most likely a bacteriocin [bacteria-killing chemical], is produced by these LAB isolates at refrigeration temperatures,” researchers wrote.
— Center for Infectious Disease Research & Policy, University of Minnesota