Sow lameness is the second leading cause of culling sows in a herd
Foot lesions can bleed away profits on swine operations, but many foot problems can be prevented by proper trace mineral nutrition in sow diets. Copper, zinc and manganese are the three trace minerals most demanded by sows. Feeding the right amounts of these minerals is essential to the longevity and reproductive success of sows.
The cost of lameness
Second to reproductive failure, sow lameness is the next reason sows are culled from herds. An average of 30 to 35 percent of sows in any given herd experience lameness, according to Zinpro Corporation field observations. Producers should target that number to be just 10 percent of their herd.
Early culling of sows also cuts into profits. This is due to potentially decreased farrowing rate, smaller litters and limited progeny performance, which are all traits linked to early parity sows.
Mike Hemann, swine account manager at Zinpro, agrees on the importance of decreasing turnover in the sow herd.
“We know that a sow must reach her fourth parity to realize her economic potential,” he says. “By working to decrease lameness in the sow herd, we can increase the longevity in sows and, in turn, can see more sows reach their economic potential.”
Lameness is a multi-factorial problem that can be attributed to numerous causes, Hemann notes. Nutrition, management, facilities and animal structure can all contribute to lameness in a herd.
Foot problems or lesions are the most visible symptoms that can be related to lameness issues. Specifically, white line cracks, heel sole cracks, severe heel overgrowth and erosion, as well as vertical wall cracks are the most painful lesions that will contribute to lameness. Setting up the sow for success early in her life through proper gilt development nutrition, phenotypic selection pressure and early training to either crates or electronic sow feeding (ESF) systems will help reduce lameness in younger parity animals.
“Lameness in a herd is not solved by one ‘magic bullet,’” he says. “Hoof trimming is also an option that some systems have chosen to adopt in order to address the issue of long toes. Early identification of moderately lame animals by management is also critical in mitigating lameness within a herd.”
Healthy sows perform better
As with any animal, when pigs feel their best they show it through their positive performance.
“Sows that are healthy and not lame are getting up and going to the feeder,” Hemann says. “They are maximizing feed intake, providing the proper nutrients to their gestating litters and piglets throughout the gestation and lactation periods, respectively.”
One indicator of good sow performance is low somatic cell counts. Trials at Zinpro have concluded that sows fed the proper amounts of copper, zinc and manganese trace minerals experience lower somatic cell counts (SCC).
“This is tied directly to the white blood cell count in the sows,” Hemann notes. “They have less inflammation and are overall healthier. This can lead to improved performance in both the sows and pigs.”
Recognize foot challenges
Several kinds of lesions can impact the health of a sow. Keeping a close eye on the overall sow foot health is imperative for producers. Lameness assessment should be part of the daily pig and sow care on each farm. Producers should watch for these foot lesions in herds:
- Toes slightly longer than normal can eventually impact sow gait when walking.
- Improper dew claws can be slightly longer than normal and can even extend to the floor surface when the pig is standing. They can also be torn or completely missing.
- Sows experience heel overgrowth and erosion when there are cracks and overgrowth and/or erosion in the soft heel tissue.
- Heel-sole crack occurs when there is a separation at the juncture of the heel and sole.
- White line is visible when a separation occurs along the white line of the foot.
- Horizontal wall cracks are evident when a hemorrhage is visible and when there is a horizontal crack in the claw wall.
- Vertical wall cracks occur when there is a vertical crack evident on the claw.
Many of these foot lesions can be caused by a nutritional deficiency or imbalance and can help be prevented by properly feeding the correct amounts of the trace minerals most needed by sows – copper, zinc and manganese. The use of these minerals at the right levels helps to optimize lifetime herd reproductive performance.
A closer look at the minerals
Manganese is essential for healthy joints, tendons and overall bone density. Hemann notes that studies have shown it can improve bone and cartilage synthesis, reproduction, immunity and enzyme system function.
“Sows with a manganese deficiency may exhibit reproduction challenges, abnormal bone and joint development, an impaired ability to make or repair joint cartilage, and skin, hair and hoof abnormalities,” he says.
Zinc is a key essential trace mineral that helps to maintain and improve the immune system, reproduction, protein synthesis, Vitamin A utilization and epithelial tissue integrity. Sows with a zinc deficiency may exhibit skin and hoof abnormalities, bone and joint problems, poor wound healing and fertility problems, Hemann warns.
Copper is needed for strong connective tissue and white line health. It is an essential trace mineral that aids in maintaining or improving reproduction, immunity, red blood cell maturation, enzyme function and collagen synthesis. Sows with a copper deficiency may exhibit poor coat color, early embryonic losses, tendon and ligament problems and bone and joint disease.
Copper and zinc also are crucial in a sow’s diet for sole, heel and horn strength and elasticity. While clinical signs of copper, zinc and/or manganese deficiencies are rare, Hemann notes that mineral nutrition and biological interactions within animals are complex.
“During times of stress – heat, reproduction, crowding, feed outages, improper diet mixing, and disease challenges – demands for these minerals may increase or even decrease,” he says. “Production responses may be minimal or, in some cases, quite detrimental. As a result, there is a need for continued trace mineral research that focuses on the production responses due to various feeding levels and interactions of all trace minerals.”
Feeding the ‘right’ amount
Hemann cautions that more is not always better when it comes to supplementing copper, zinc and manganese. First, producers and nutritionists should ensure the nutrients in the formulated ration meet or exceed National Research Council (NRC) requirements.
Yet, some minerals can have antagonist effects with other minerals and nutrients, and – when fed at excess levels – can deter optimal production. For example, high levels of iron in the water may tie up other minerals and nutrients, rendering them of marginal benefit to the animal, he notes.
“We recommend that these complexed forms of trace minerals are fed as a partial replacement with inorganic sources of minerals in the ration,” Hemann says. “As with most production practices, everyone has their individual opinions as to the proper balance and level of various nutrients. That is why it is imperative to have an open dialogue with your consulting nutritionist concerning nutrient levels and feeding programs for your operation or system.”