Swine Species Symposium II
By: Lauren Soranno
On the afternoon of July 22, 2020, viewers gathered virtually for the second Swine Species Symposium as part of the ASAS-CSAS-WSASAS Virtual Annual Meeting. The session focused on the issue of pig mortality along with nutritional methods, alternative management practices, and other strategies to potentially increase the rate of survival in swine herds. Dr. Caleb M. Shull, the director of research and innovation at The Maschhoffs, began the session by discussing the overall problem of pig mortality, why there has not been improvement in mortality rates, and how mortality rates can be improved. Although the total piglets born per litter has improved over the past 10 years, pig mortality has not seen any improvement. Dr. Shull explained that improving pig survival is not an easy task because of mortality research requirements, the death of a pig is multifactorial, and competition with other traits (litter size, ADG) that pull resources away from mortality research. He then went into depth on five potential paths for improving mortality: people, health stabilization, research and development, technology, and collaboration. There have been positive steps taken towards improving mortality, but mortality improvement needs to remain a focus for the industry to make headway.
Dr. Jason W. Ross, a professor at Iowa State University, continued the discussion turning the focus to sow mortality specifically. Sow mortality has increased over the past few years with the main cause being pelvic organ prolapse (POP). Understanding the potential causative factors of sow POP as well as the underlying physiology occurring within a sow prior to POP is critical in order to then develop and disseminate prevention strategies to ultimately reduce POP incidence and sow mortality. Dr. Ross went into detail about the Prolapse Project which concluded that body condition score, feeding strategy, and perineal scores are all important indicators of prolapse risk. Also, other specific biological changes such as changes in vaginal microbiome and changes in serum metabolites are apparent in sows at a higher risk for POP. With this knowledge, there is potential to create intervention strategies that can then be employed to reduce the occurrence of POP.
After a quick break, Dr. Mike D. Tokach, a professor at Kansas State University, presented on potential ways to reduce post-weaning mortality. Similar to the previous presentations, Dr. Tokach also stressed the importance of first understanding the major causes of post-weaning mortality to then help determine the places to start improving wean-to-finish survival. The major causes can be broken up into non-infectious and infectious causes and then further categorized into high, moderate, and low magnitude of impact. Non-infectious mortality factors include birth weight, pre-weaning management, weaning age and weight, season, ulcers, rectal prolapse, abdominal torsions, etc. Infectious mortality factors include respiratory diseases, enteric diseases, and systemic diseases. Taking these factors into account, Dr. Tokach stressed the importance of producers focusing on increasing birth and weaning weight, colostrum intake, weaning age, elevating biosecurity measures, and determining the best management strategy to handle pathogens already present in the herd (control, elimination, depopulation).
To conclude the symposium, Dr. Janet C. Remus, senior technical director at DuPont Animal Nutrition, discussed the concept of Nutribiosis and the factors that need to be considered when trying to produce a robust and resilient pig. Nutribiosis is the interplay between nutrition, GI microbiome and gut/immune function. There are many factors that sit behind the usual parameters as to what makes a robust pig such as birth and wean weight, sow milk production for her piglets, microbiome profile and development, GI tract function and maturation, nutrition, environment and so on. Within those, the microbiome itself is impacted by many factors as well such as age, feed, sex, immunosuppressive viruses, etc. Dr. Remus discussed how microbiome diversity is favorable as it allows for more resilience and robustness in how it can deal with sudden insults and in turn help the pig be more resilient. Nutrition programs should be targeted to encourage development of diverse microbiome profile as the pig ages, so that can in turn positively impact gut and immune function and ultimately work towards producing a robust and resilient pig. Overall, recent collaboration across the swine industry and the emergence of some strategies to improve mortality are positive steps forward and need to continue to move forward in order to actually see improvements in mortality rates.