Knowing the enemy: PRRS and PCVD
The swine industry is constantly vigilant of viruses that can infect their herds. Viruses can harm the pigs and cause a lot of economic damage. We have seen how PRRS and PCVD diseases have managed to infect many animals through time. In some cases, both viruses are present simultaneously, making the situation even riskier. Before this happens, farmers need to protect their pigs at all costs.
The words that farmers and swine producers dread to hear from their local vet are “your pigs are sick.” At this moment, they realized that the viruses had breached their biosecurity defenses. That is why we must always be watchful. But how did the viruses manage to reach their herd? It is not as complicated as you may think. A virus travels in pigs that do not look sick or even on a dirty truck. It takes only a small window of time for them to infiltrate. When the biosecurity and preventive measures are not secure, the virus seizes the opportunity and infects the herd, taking advantage of the situation. To avoid this scenario, one must know the enemy and protect against it.
Knowing my opponent
PRRS (Porcine Reproductive and Respiratory Syndrome) is caused by a virus that strikes both adult pigs (sows) and growing piglets. It will affect the reproductive system causing abortion, stillbirths, weak neonatal piglets1, and mummified fetuses for sows2. In piglets of all ages, it targets the respiratory system affecting the breathing capacity, and in the worst cases, even drawing their last breath. PRRS virus has spread worldwide, making this a global problem for the swine industry. The total cost to the industry has been estimated at 4 billion euro per year and 1.5 billion euro annually in the EU3.
PCVD (Porcine Circovirus Disease) is caused by the PCV2 virus that invades the pig immune cells and has a devastating effect. It can cause severe weight loss (wasting), difficulty breathing, and diarrhea. It impairs the immune system, leaving the pigs susceptible to other swine diseases. PCV2 can be associated with many disease syndromes such as pneumonia, porcine dermatitis, nephropathy syndrome (PDNS)4, porcine respiratory disease complex (PRDC), inflammation of the small intestine (enteritis), and in some cases, reproductive failure in sows.
PRRS and PCV2 viruses generate more trouble when they act together. Scientists have discovered that these two viruses potentiate each other. Both can cause production losses by reducing daily weight gain and leading to respiratory disease in growing pigs. Some may even develop a severe case of pneumonia. It is a very common co-infection under field conditions. They weaken the pigs leaving them susceptible to other diseases. But one should be careful because the symptoms can be mistaken for other respiratory disorders. Therefore, it is crucial to involve an experienced vet to examine the pigs to establish the proper diagnosis.
Strategic planning
After recognizing my adversary, it is easier to devise a defense plan before the situation gets serious. We can guard them by applying disease control measures, including vaccines, better biosecurity, and management. The disease impact won’t be as critical when the herds are vaccinated.
Farmers need to vaccinate their pigs against both PRRS and PCV2. Last year, there were new developments regarding PRRS and PCV2 virus vaccines. In Boehringer Ingelheim, we have been working through innovation, leading to a unique solution that prevents these two viruses in one injection. There is less stress on the pigs and farmers and helps them with efficient farm time management.
Preparing well-using biosecurity measures, good piglet care, and vaccines are vital steps that can help you protect your pigs against these viruses.
References:
1Oh, T.; Suh, J; Park, K.H.; Yang, S.; Cho, H.; Chae, C. A comparison of Pathogenicity and Virulence of Three Porcine Circovirus Type 2 (PCV2) Genotypes (a, b, and d) in Pigs Singularly Inoculated with PCV2 and Dually Inoculated with Mycoplasma hyopneumoniae and PCV2. Pathogens 2021,10, 979
2Boehringer Ingelheim. Impact of PCV-2 and PRRSV co-infections in Swine Production.
3Internal data on file
4Swine Disease Manual (Fifth Edition) - SECTION II: Diseases caused by viruses -- Porcine Circovirus Associated Diseases
Jeong J, Kang HS, Park C, et al. Comparative efficacy of concurrent administration of a porcine circovirus type 2 (PCV2) vaccine plus a porcine reproductive and respiratory virus (PRRSV) vaccine from two commercial sources in pigs challenged with both viruses. Journal of Swine Health and Production 2016; 24(3):130-141