Swine mortality, particularly those caused by infectious pathogens, poses biosecurity risks and causes significant economic impact. Dead handling structures may act as sources of viral environmental contamination, but limited attention has been given to their role in biocontainment and bioexclusion of pathogens in and around farms. In this study, we tried to diminish this problem by assessing the environmental contamination around dead animal disposal structures in wean-to-finish farms and determining if the contamination levels differ according to how dead animals are managed.
Continue reading “40-farm study reveals swine mortality site virus risk”Category: National Hog Farmer
PRRSV variants under monitoring
Porcine reproductive and respiratory syndrome virus is a major threat to pig production worldwide. The virus is constantly changing, with new variants appearing every year. Some of these new variants can spread more easily or have a greater impact on your herd’s health and productivity. An example is the emergence of a new PRRSV variant named 1C.5 (previously referred to as L1C 1-4-4, or 1-4-4) in late 2020. In the past, monitoring systems have had a difficulty identifying new variants like this quickly enough to allow for a rapid response, and they often focused on describing epidemics that had already happened.
Continue reading “PRRSV variants under monitoring”Veterinary team targets FAD hotspots to protect U.S. livestock
A single outbreak of a foreign animal disease—whether foot-and-mouth disease, African swine fever, or peste des petits ruminants—can bring a nation’s livestock industry to a grinding halt. These viruses are fast-moving, hard to control, and devastating to animal health and rural economies alike. Infected animals may suffer painful symptoms or die. Even in countries where the diseases are not currently found, the threat looms large: trade restrictions, emergency culling, and lost market access can trigger billions in losses.
Continue reading “Veterinary team targets FAD hotspots to protect U.S. livestock”Does vaccination influence PRRSV evolution?
RFLP 1-7-4, variant 1C.5 (aka L1C-4-4), or 1C.5.32 – these are some of the infamous PRRSV-2 viruses that have caused massive production losses over the past decade. Regardless of how people named or classified them, one thing these epidemic waves had in common was that they were caused by genetic variants that were novel at the time, and vaccination, especially widely used modified-live virus commercial vaccines, failed to mitigate their spread. Many viruses are in an arms-race with host immunity, evolving to evade host immune mechanisms. The less-than-perfect available immunization strategies combined with the expanding genetic diversity seen for PRRSV-2 raises the question:
Does the use of MLV vaccines play a role in shaping wild-type PRRSV-2 evolution, potentially driving the emergence of new variants?
A newly published paper from the University of Minnesota1 attempted to answer that question in a controlled experimental setting to compare the evolution of PRRSV-2 through pig-to-pig infection chains under different MLV vaccination conditions.
Continue reading “Does vaccination influence PRRSV evolution?”Is PRRSV 1C.5 more airborne than other variants?
The rapid spread of porcine reproductive and respiratory syndrome virus variant 1C.5 (aka L1C 1-4-4) a few years ago prompted the question whether this newly identified PRRSV variant was more transmissible through the air than other endemic variants circulating at that time in pigs.
The Torremorell research lab, in collaboration with faculty in the Swine Group at the University of Minnesota College of Veterinary Medicine and faculty in Mechanical Engineering sought to answer the question whether aerosolization of clinically relevant PRRS virus differs among variants and if so, are the differences due to the particle size, load and viability of virus-laden aerosols, and whether infected pigs with different clinical affectation differ in their ability to generate airborne viruses. To address this question, we systematically evaluated the stability of variants in experimentally generated aerosols and also compared levels and trends of virus-laden particles in aerosols collected from experimentally infected pigs.
Continue reading “Is PRRSV 1C.5 more airborne than other variants?”