Lameness in Sows
It's all too common, a favourite sow becomes lame after farrowing, your boar cannot serve because of pain or you are at a loss as to why one sow has isolated herself, will not stand up, will not eat and is losing condition rapidly.
There are a few factors that will contribute to lameness and they include bacterial infections, sow's environment, heredity and nutrition.
Lameness can be an issue with the feet or a degenerative joint disease.
Trauma to the foot from injury to the claw or penetration of foreign objects (thistles, thorns, nails, metal etc) that have lodged or caused damaged and infection can result in 'club foot' and cause so much pain that the sow will avoid contact with the herd and it may even be too painful for her to walk to a feeder. This condition usually responds to treatment after the sow is isolated and fed on her own.
Osteochondrosis or OCD, results from damage to muscles, tendons and bones. Unfortunately prevention is much more successful than a cure for OCD. Poor leg conformation can succumb to the stresses and pressure of rapid growth, poor nutrition and trauma.
We always stress the importance of selecting sound breeding stock because they are the foundation of your business. We have discussed in another section what to look for when selecting breeding animals and two points made where a nice straight back and sows that have a good hold on the ground with the feet. No ballerinas or sows that appear to be standing on their toes.
This diagram shows the dramatic effect poor conformation has on the structure of the legs and how it could impact on the sow's ability to withstand the pressures of lactation, mating, poor nutrition or even living conditions slippery, muddy surfaces, rough ground or poor housing. You can see the direct pressure placed on joints and cartilage in the pig with poor conformation. Note the 'tippy toe' appearance of the second pig.
OCD is a sad fact in the intensive pork industry and can be a result of forced unnatural growth rates, breeding for specific traits such as leanness and body length, high litter sizes and more efficient feed conversion.
OCD will impact on the free range farmer because some of our genetics are sourced from the intensive industry but poor selection of breeding stock and a lack of knowledge about pig nutrition are the major contributors.
Its not always the producers fault (apart from not detecting poor conformation in the first place) some sows put everything into milk production during lactation and some times even the best nutrition and adlib feed is not enough to stop her condition falling away or to prevent permanent and debilitating lameness. Fractures to the spine can occur during lactation or at weaning.
In many cases OCD results in progressive and irreversible damage to the sow and causes immense suffering. Bones can break and could display as a leg swinging freely and the sow unable to put that foot to the ground, or a sow that is sitting in a dog like position on her haunches and unable to stand with back legs straight after being assisted to a standing position. You may also witness a rear end that sways and back legs crossed if the sow is brought to her feet. These types of injuries do not usually resolve and in most cases it is kindest to humanely destroy the sow.
If you feel that the sow is not suffering and that you may be able to nurse her back to health with constant attention and moving the pig several times a day, expect a very long recovery and at least 6 weeks before you can really tell if any of your efforts are having any impact. Even if the sow does recover this bout, she will probably succumb again as nothing can be done to correct poor conformation or the degeneration of her bones and cartilage that has already occurred.
Dont forget that Erysipelas can cause lameness during the course of the disease. If a pig is found suddenly lame in the paddock, and has not just farrowed or been weaned, check its temperature and herd health status re this disease. The telling sign will be that antibiotics will help the pig with erysipelas but OCD does not respond.
Your best defense against sow lameness is prevention.
- Select breeding animals well and think of the diagrams above when viewing sows.
- Feed your animals not just well, but understand their nutritional needs and all stages of growth and lactation.
- Manage sows well during farrowing and watch any sow losing too much condition. You may have to wean early.
- Don't ignore a limping sow. Foot issues can escalate and the sow will lose conditions.
- Prevent injuries by removing slippery surfaces and not grazing sows on sharp stoney ground or areas covered in thistle or burrs. Keep paddocks free of rubbish.
- Dont let your boars get too big. Keep them young and in not too fat condition to prevent harm to the sow.
- Vaccinate your herd for Erysipelas