Focus on immunity and gut health at Feedlot Day

Estimated reading time: 3 minutes

Recently, over 450 people attended the 2024 Octavoscene Feedlot Day at the CSIR International Convention Centre in Pretoria.

The event’s topics were chosen to address current issues and the feedlot industry, particularly those related to the digestive system.

One of the key topics was foot-and-mouth disease (FMD), which has wreaked havoc on the South African livestock industry in recent years, most recently in the dairy industry. Dr Shaun Morris, CEO of Octavoscene, noted that one positive outcome of the FMD outbreaks was the improved health of many cattle due to stricter adherence to biosecurity and quarantine practices. “And if you don’t quarantine, I don’t want to know you. Lose my number.”

However, Dr Morris believes it is time to reassess how South Africa deals with these outbreaks. 

Read more about how a new feedlot must be build here.

Rising risks of transboundary diseases

Prof Leon Prozesky, veterinary pathology diagnostic consultant at Path Diagnostics Africa, stated that FMD has been the most devastating event in South Africa. However, when considering the transboundary diseases lurking at the country’s borders, FMD seems relatively mild. He expressed particular concern regarding an outbreak of contagious bovine pleuropneumonia in Botswana and a disease identified by Zimbabwean authorities as January disease. “There is a real chance that those countries could lose their commercial farming industry,” Prof Prozesky said. “I only hope that we will be able to identify these diseases timeously if they reach South Africa.”

Immunity starts here

Prof Christopher Chase from the Department of Veterinary and Biomedical Sciences at the South Dakota State University discussed rumen micro-immunity and the three levels of defence in ruminants.

The first line of defence is barriers, that prevent invasions and infections, such as mucous, tears, gastric pH, saliva, skin and antimicrobial peptides. “If that barrier is breached, the only thing that will happen is the body will go into surveillance mode. It is kind of like a smoke alarm, detecting problems.”

In this instance, the ‘alarm’ can be something like inflammation – which is the second line of defence. “Inflammation is our friend, but as we learned through COVID-19, it can also be our enemy if it is not working efficiently.” Inflammation activates the things that you would normally associate with a vaccine, Prof Chase added. “It activates the production of antibiotics by involved cells and T-cells, which are important in the overall immune response.” In essence, the first and second lines of defence work together.

“To maintain these defences, it is crucial to ensure the animal has a healthy microbiome,” Prof Chase said.

The microbiome matters

Henning Vermaak, managing director at Essential Nutrient Systems, discussed the latest research on the gut microbiome and liver abscesses. He affirmed that the microbiome is an important component of the host animal and that any microbiota changes could disrupt the immune function. However, more research was still needed on feedlot inductions and treatment regimes in commercial farming enterprises according to him. – Susan Marais, AgriOrbit