September 15, 2020


US researchers to find targets to mitigate fescue toxicosis effects in cattle


The United States Department of Agriculture (USDA) has given a US$500,000 grant to the University of Georgia to find targets to mitigate fescue toxicosis effects in cattle, which costs the US beef industry over US$1 billion annually.


Fescue toxicosis has been an issue for cattle producers in the US and South America, which causes weight gain, digestive and reproductive problems such as lower calving rates, plus cattle food and leg issues. 


The study will be led by Nikolay Filipov, College of Veterinary Medicine Professor, together with Professor Todd Callaway, College of Agricultural and Environmental Sciences Associate of the Department of Animal and Dairy Science, as well as Professor Nicholas Hill of the Department of Crop and Soil Sciences, in partnership with Associate Professor Garrett Suen of the University of Wisconsin and Professor Dean Jones of Emory University.


The USDA's National Institute of Food and Agriculture is funding the grant project.


Filipov said a 20 to 30% decrease in weight gain or a 30 to 40% decrease in calving rates means major monetary losses for cattle producers.


Filipov said the study aims to characterise the disease globally, looking at multiple levels of the gut microbiome of cattle to see how they metabolise all of the different molecules of fescue to characterize those, plus how those interact with the bacteria that are part of the cattle's GI tract.


He said the study will result in more specific ideas of types of management strategies or treatment approaches for the disease that cannot be found with more simplistic approaches.


The study will be significant to cattle producers, especially as Georgia's cattle producers account for 25% of the country's beef. The cattle feed on fescue grass because of its a high drought tolerance and has a long grazing season but contains a fungus that lives within the plant not only gives its desired traits but produces alkaloids that are toxic to the livestock who graze on it.


Filipov said it is not feasible to completely remove the toxic endophyte-containing grasses from the environment even though endophyte strains that do not produce toxic alkaloids have been identified.


He said current practices to manage fescue toxicosis such as stopping pregnant cattle from grazing during late gestation, rotational cattle grazing or additional dietary supplements have limited success.


The study hopes to find a solution based on whole-animal and animal-plant-endophyte approaches.


-      University of Georgia