48 NEBRASKA CATTLEMAN April/May 2026 1-888-927-3272 • wardcraft.com Because in rural living, the laundry works as hard as the kitchen. New plans featuring fully designed utility rooms — spacious, practical, and built for everyday living. 6,100 Homes Built 65 Plans or Custom Build 1230 E 9th Minden, NE • 614 Maple Clay Center, KS Wardcraft Homes Oakley 1,680 sq ft New Plans, Huge Laundry Rooms. HEATHER BRADFORD, PH.D. | U.S. MEAT ANIMAL RESEARCH CENTER PEERS LIVER ABSCESS RESEARCH AT USMARC IS THERE A GENETIC SOLUTION? Liver abscesses continue to cost feedlot operators and packers more than $900 million every year. Understanding what drives these abscesses – and what doesn’t – can help producers make better management and breeding decisions. Liver abscesses affect 20 to 30 percent of carcasses. And in many carcasses, abscessed livers adhere to surrounding tissues, which may require additional trim losses. Because abscessed livers are condemned and not sold for human consumption, costs result from the lost liver value, lighter carcasses, reduced feed efficiency, increased labor and slower processing speeds at the packing plant. It is currently understood that feeding high-concentrate diets increases risk of ruminal acidosis, which can damage the lining of the rumen and enable bacteria to leave the rumen and travel through the bloodstream to the liver, producing an abscess. Preventive strategies involve changes to feeding management and include: 1. Lengthening the feedlot ration transition period to a high-concentrate diet; 2. Increasing particle size in the ration; 3. Increasing the roughage content of the diet, particularly at the end of the finishing period; 4. Feeding the antibiotic tylosin phosphate. Tylosin phosphate falls under the Veterinary Feed Directive and requires veterinarian approval. Alternative management and non-antibiotic strategies are being investigated to address liver abscesses, and to reduce antibiotic use and the possibility of antibiotic resistance. HERITABILITY AND GENETIC IMPACTS ON LIVER ABSCESSES Heritability measures the variability of a trait that is controlled by the animal’s genetics rather than environmental factors like feeding management, weather and production system. Based on an analysis of 9,000 crossbred cattle at the U.S. Meat Animal Research Center (USMARC), liver abscesses were characterized as lowly heritable (h2 = 0.04), a finding like many other disease-related traits, and a heritability estimate lower than common production traits like calving ease and cow stayability. Because liver abscesses are not easily identified in the live animal, with no externally observable indicators and limited reliability of ultrasound imagery to detect liver abscess formation throughout the feedlot period, progeny testing would likely be the only reliable approach for potential genetic selection against liver abscesses. Unfortunately, progeny testing requires many carcasses from known sires, takes many years of data accumulation and has a tremendous cost for what may be little return. CROSS-BREEDING HETEROSIS Because genetics play a small role, researchers proposed that heterosis might influence liver abscess risk. Unfortunately, based on USMARC data, heterosis does not contribute to liver abscesses, an indication that purebred CONTINUED ON PAGE 50
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