L. intracellularis Infection, Risk Evaluated

Allen Page, PhD, DVM, a former University of Kentucky (UK) Gluck Equine Research Center post-doctoral fellow, gave a talk about Lawsonia intracellularis, the bacteria that causes equine proliferative enteropathy (EPE), at the 4th Annual UK Equine Showcase, held Jan. 23 in Lexington, Kentucky.

 

Equine proliferative enteropathy is a disease of foals that causes hyperplasia, or thickening of the walls of the intestinal tract. L. intracellularis mainly affects weanlings and causes anorexia, rapid weight loss, fever, depression, a rough hair coat, throat latch and ventral edema (fluid swelling), colic, and diarrhea.

 

In most cases if caught early, L. intracellularis infection is not fatal; however, it might take a couple of months for affected foals to catch up to others in body condition. In rare instances, veterinarians have diagnosed EPE cases and treated them appropriately, yet the foals die as a result of cell injury or death of cell tissue in the intestinal tract.

 

In a recent study, Page and David Horohov, PhD, Jes E. and Clementine M. Schlaikjer Endowed Chair at the Gluck Equine Research Center, Interim Chair of the Department of Veterinary Science, and Interim Director of the Gluck Equine Research Center, found that colts were at a significantly higher risk than fillies for developing EPE. However, numerous cases were reported in fillies as well. The study also showed that foals who were weaned after August were at lower risk for developing EPE than earlier weanlings.

 

“We found that mares were more at risk for exposure to Lawsonia during the summer months than their foals,” Page said. “Since most foals were still nursing during this time and likely exposed to the same environments and materials as the mares, we interpreted this to mean that the mares were somehow protecting their foals from exposure to Lawsonia during the summer.”

 

There are currently three tests available for L. intracellularis--the serum immunoperoxidase monolayer assay (IPMA), the ELISA test, and a fecal PCR test. The IPMA and ELISA both test for antibodies against Lawsonia, whereas the PCR test detects the bacteria’s DNA in feces.

 

Video: Swine Industry Advances: Biodigesters Lower Emissions and Increase Profits

Analysis of greenhouse gas (GHG emissions) in the Canadian swine sector found that CH4 emissions from manure were the largest contributor to the overall emissions, followed by emissions from energy use and crop production.

This innovative project, "Improving Swine Manure-Digestate Management Practices Towards Carbon Neutrality With Net Zero Emission Concepts," from Dr. Rajinikanth Rajagopal, under Swine Cluster 4, seeks to develop strategies to mitigate greenhouse gas emissions.

While the management of manure can be very demanding and expensive for swine operations, it can also be viewed as an opportunity for GHG mitigation, as manure storage is an emission source built and managed by swine producers. Moreover, the majority of CH4 emissions from manure occur during a short period of time in the summer, which can potentially be mitigated with targeted intervention.

In tandem with understanding baseline emissions, Dr. Rajagopal's work focuses on evaluating emission mitigation options. Manure additives have the potential of reducing manure methane emissions. Additives can be deployed relatively quickly, enabling near-term emission reductions while biodigesters are being built. Furthermore, additives can be a long-term solution at farms where biogas is not feasible (e.g., when it’s too far from a central digester). Similarly, after biodigestion, additives can also be used to further reduce emissions from storage to minimize the carbon intensity of the bioenergy.