Liver Abscess Control and Prevention
There is a 2-inch trip from the rumen to the liver, and if the rumen isn’t well, then issues will transmit to the liver, said Kelly Lechtenberg, owner and veterinarian of Midwest Veterinary Services and Central States Research Centre in Oakland, Neb. He spoke to more than 100 attendees from five countries at the fifth International Symposium on Beef Cattle Welfare in Manhattan, Kan., June 8-10.
Calves most often get liver abscesses because of acid generation from ruminitis, and changes can occur quickly, said Kelly Lechtenberg, Midwest Veterinary Services and Central States Research Centre.
Calves most often get liver abscesses because of acid generation from ruminitis, he said, and changes can occur quickly. There are five entry spots for bacteria into the liver, including the hepatic artery, bile duct, umbilical vein, direct extension and the portal vein, which is most common in fed cattle. Ruminal wall abscesses or abrasions will send bacteria to the liver.
The liver has a good immune system; however, leukotoxins similar to Mannheimia haemolytica fight the liver’s immunity well and can overcome it. He noted that many bacteria can cause abscesses, but Fusobacterium necrophorum is the biggest culprit.
He said veterinarians can see 75% of the liver’s volume with ultrasound, so large abscesses are visible. Abscesses that are less than 1 centimeter (cm) tend to resolve themselves, but when they consolidate and form a bigger abscess, they cause issues.
He shared data from Elanco on liver-abscess prevalence in beef breeds and Holsteins since 2005. Beef breeds remained relatively consistent around 15%-16%; Holsteins were consistently in the 20% range, jumping to the mid-30% range in the last few years. He suggested this could be because dairy steers are fed longer or potentially have a genetic predisposition toward them.
As abscessation prevalence goes up, so do the instances of A+ abscesses, the term for the large abscesses. This is an issue because A+ abscesses have a negative effect on carcass weight and welfare, he noted. Reasons for prevalence include those of rumen acidosis, namely days on high-concentrate feed. He did note that there are regional differences in prevalence, which may be attributed to feedstuff seasonality and intake patterns.
He concluded that calves with liver abscesses are often thought to have bovine respiratory disease (BRD), though liver abscesses are susceptible to BRD treatments.
Watch for additional coverage of the 2016 ISBCW on www.angus.media and in the Angus Journal and Angus Beef Bulletin. Comprehensive meeting coverage will be archived at www.api-virtuallibrary.com/meetings_other_news.html.
