Preventing sow lameness is a wise goal
Generally, a replacement gilt does not pay for herself until she has farrowed at least three litters. (Wilson, 2015, Stalder et al., 2003, Scholmann and Dijkhuizen, 1989). For each additional litter a sow has beyond the third, the fixed cost of piglet production drops drastically. As a result, increasing longevity and reducing sow culling must be a key focus of any profitable pork operation.
The greatest percentage of culling occurs in gilts and first-parity sows, so limiting the proportion of younger sows in a herd can decrease the culling rate. Increasing the proportion of gilts within a herd can cause destabilization of herd health status and also depress grow-finish performance. This is due to the impaired performance of gilt offspring, which have been shown to have higher mortality rates and poorer growth performance in the grow-finish phase (Roethe and Kennedy, 1995).
Knauer et al. (2007) reported that the majority of parity 3 and younger sows are culled due to feet and leg problems and reproductive failure. Cystic ovaries were found in only 6.3 percent of sows, however, which was significantly lower than the reported percentage of sows culled for reproductive failure according to recordkeeping summaries.
The following tips can help you prevent lameness issues in your sow herd:
- Gilt selection for feet and leg soundness is an essential first step in decreasing lameness in the sow herd. Particularly, bucked-kneed front legs have been shown to negatively impact sow longevity, whereas soft front pasterns positively impact longevity. Additionally, ideal toes (large, evenly sized and spread apart) allow for better distribution of weight (Stalder, 2005). More information on how to evaluate replacement gilts can be found here.
- Check all flooring areas and sharp surfaces with which a sow may come into contact. Flooring around cool cells, access panels over manure valves, exposed bolts, or other sharp equipment might create surfaces that may injure the hoof.
- Over-conditioning is most often associated with heel bruises and under-conditioning is most often associated with other hoof lesions and shoulder sores (Karriker, 2013). Focus on managing individual feed intake during gestation and lactation to reduce the numbers of animals falling into these categories.
- Corrective hoof trimming may be employed when overgrown toes cause lameness. The goal with hoof trimming is to correct hoof length and the angle of the toe. This is thought to reduce tension between the horn of the hoof and the bone underneath so that blood supply is not compromised (Karriker, 2013). Generally, restraint is required when hoof trimming, so this procedure requires the investment of additional time and resources.
- Deficiencies in vitamin D, calcium, and phosphorus are most often thought of as the nutritional culprits that could result in structural unsoundness or lameness. Due to their biochemical and physiological functions, vitamins A, C, and E, and trace minerals selenium, niacin, copper, manganese, magnesium, and zinc are also theorized to impact structural soundness. However, if these nutrients are deficient, clinical signs such as skin lesions, unthriftiness or diarrhea will typically be observed before symptoms of lameness.
- Chronically high levels of mycotoxins may cause lameness by interfering with absorption and utilization of nutrients.
Increasing the parity profile of any sow herd will result in larger numbers of healthier pigs in your finishing barns. The Vita Plus swine nutrition team wants to help you improve the profitability of your operation by providing our technical expertise and a variety of scientifically-formulated products designed to meet or exceed the nutrient requirements of today’s highly prolific sows. Contact your Vita Plus consultant to learn more.
About the author: Dr. Leah Gesing is a Vita Plus swine technical sales and support specialist. She earned her bachelor’s degree in animal science from Iowa State University. She continued there to earn her master’s degree in animal physiology, studying on-farm factors affecting market hog transport losses. She then went on to the University of Illinois to earn her Ph.D. in animal sciences. While in school, Gesing was involved with numerous research projects, teaching experiences, internships, and international travel. Specifically, she conducted applied research in swine genetics, health, management and reproduction with Dr. Mike Ellis. Her Ph.D. project evaluated the effect of timing of OvuGel® administration on reproductive performance in gilts synchronized for estrus.