F
EXTRUSION High-shear extrusion:
An alternative method of processing waste by-products and feed ingredients in times of infectious disease outbreaks
O
by Janeth Colina, Insta-Pro International, USA
utbreaks of infectious diseases threaten the health of livestock and have a major economic impact on the food industry. Diseases affecting the poultry industry such as avian influenza, virulent Newcastle disease and salmonella, cause flock’s devastation. On the other hand, the world pork industry is facing risks with the outbreak in China and Eastern Europe of African Swine Fever (ASF), a highly contagious hemorrhagic disease affecting both domestic and wild pigs. The serious decrease in production and the subsequent economic losses due to disease outbreaks are tangible in high mortality of animals, revenue decreasing, expenses related to quarantine measures and the subsequent increase in prices of animal products. Prevention through a systematic biosecurity program is one of the bests ways to protect swine and poultry from the risk and dissemination of infectious diseases. However, it is relevant to point out that, in the case of the outbreak of an infectious disease the pathway of spread may involve contaminated infectious inanimate objects (ie animal trailers, worker’s boots, utensils, etc), feed ingredients and additives. In fact, it has been demonstrated that most viruses survived in commodity soybean meal, lysine hydrochloride, choline chloride,
64 | February 2020 - Milling and Grain
among others (Dee et al, 2018) which attributes to the rapid spread of a pathogen during a foreign animal disease outbreak. One report (Dee et al, 2019) about the survival of viral pathogens in animal feed ingredients under transboundary shipping models highlighted that the half-life estimates of ASF in conventional and organic soybean meal is over four days. The USDA has reported that importing of ASF-contaminated products, including contaminated pork products and feed ingredients derived from ASF-infected pigs remains a significant threat to the introduction for ASF-free countries. While the data is limited, a study demonstrated even at minimal infectious doses, ASF-contaminated feed and water can lead to disease in pigs (Niederwerder et al, 2019). Taken together, importing ASF-contaminated products is a major concern because the entrance of complete feed, ingredients, and additives to swine farms is a common practice which implies a higher risk of exposure and transmission of diseases. While the origin point of introduction remains unclear, the vast and rapid spread of ASF across both Europe and Asia could in part be attributed to transmission from ASF-contaminated products, including contaminated pork and animal-derived feed ingredients. For this reason, enhanced biosecurity, including surveillance and entry control of contaminated pork, by-products, and even feed ingredients of plant origin are needed. Considering alternative methods for processing ingredients for animal feeding and disposal of contaminated by-products is an