January 04, 2021

Interpretive Summary: Rumen epithelial transcriptome and microbiome profiles of rumen epithelium and contents of beef cattle with and without liver abscesses

Interpretive Summary: Rumen epithelial transcriptome and microbiome profiles of rumen epithelium and contents of beef cattle with and without liver abscesses

By Anne Zinn

Liver abscesses in feedlot steers is the highest cause of liver condemnation and is estimated to cost the beef industry $64 million each year. Abscesses are the result of bacteria entering the liver as a result of damage to the rumen wall. This damage allows bacteria to invade the bloodstream and colonize the liver. There currently aren’t any methods to predict whether an animal is more susceptible to liver abscesses or to determine whether the animal currently has liver abscesses prior to viewing the liver at harvest.

A recent study published in the Journal of Animal Science aimed to determine whether the expression of various rumen epithelial genes and changes in the microbial populations in the rumen epithelial tissue and content were associated with liver abscesses. The current study was part of a larger study designed to evaluate whether the essential oil limonene fed as a supplement to cattle would reduce liver abscesses.

The results of the present study identified expression differences between inflammatory response genes in the rumen tissue of animals with liver abscesses compared with control animals upon slaughter. To better understand the molecular mechanisms of liver abscesses prior to development, samples from live animals must be evaluated, which can be time-consuming and invasive. There is evidence from past research to suggest that animals with liver abscesses can be distinguished from healthy animals by collecting blood - it is possible that the differences detached here may be reflected in the circulating blood or may cause changes in the levels of other genes or proteins that could be detected in the blood, serum, or plasma of animals with liver abscesses.

This study was the first step in evaluating the mechanisms in the rumen pipeline that may be contributing to damage to the rumen wall and the development of liver abscesses in cattle. The results produced several functional candidate genes and epimural bacterial differences to be able to gain more insight into the molecular mechanisms underlying liver abscess development in cattle.

The full paper can be found on the Journal of Animal Science website.