From the Editor

Sows need individual attention

The newest trend in sow housing is indoor group housing. I agree that this may be the best system for most sows. I am an advocate of sow exercise, movement, and socialization. Most sows in a group choose to lie together. A well-designed and well-managed group housing facility likely promotes sow well-being. However, poorly designed and poorly managed group sow housing systems are disastrous. In my opinion, from the standpoint of sow well-being, these systems are substantially worse than sow crates. You only have to see one sow "beaten up" by the other sows in the pen to realise how inhumane sows can be to one another. Similarly, sows that are in oestrus and mounting one another often cause lameness in the mounted sow.

Dr Tim Blackwell's Howard Dunne Memorial Lecture1 prompted me to write this editorial. Dr Blackwell eloquently discussed our responsibility as swine veterinarians for the well-being of the pigs under our care. He discussed group sow housing as a positive alternative to gestation crates. I have visited two of the three farms that Dr Blackwell described. These farms do have well-designed, well-managed group sow housing. The sows in the group pens appear well fed, comfortable, and content. But these farms also have sow crates. The sows are weaned into crates and stay in crates until they are 30 days pregnant. They are not mixed together at weaning nor are they in a group while they are all coming into heat. Pregnant sows are moved into pens in groups of five to 28. This mixing technique reduces fighting.

Dr Blackwell also discussed the veterinar-ian's responsibility for attention to individual animal welfare. There are sows that do not thrive in a group housing facility. I know this because one of my clients has only penned gestation housing. Weaning sows into pens has caused massive battles that occasionally lead to permanent crippling of a sow. Some sows bully others. Other sows remain submissive and are never accepted by the group. I remember one sow that was "forced" to sleep over the slats, away from the rest of the group. These problems were very obvious because my client had no alternative housing for his sows.

I discussed this potential problem with the owners-managers of the two barns Dr Blackwell and I both visited. Both people said that some sow crates are necessary. Sows that are too thin coming from the farrowing room are kept in crates so that they can be feed individually. Bully sows and sows that are not eating in the pens are put back into crates. One producer felt that he needed a minimum of 40% of his sow capacity in crates. This will accommodate 30% of his sows from weaning to 30 days post breeding and a further 10% that do not adjust to the group situation. He said that he often moves two sows out of a group of 20 in a pen and puts them back into crates. The second producer believed that only 2 to 3% of his sows do not thrive in the group pens. However, he does still have crate accommodation for 30% of his sows.

There is no single housing system that is ideal for all animals. Sows have individual needs based on their level of dominance, body condition, and physical health. I believe that farms with both gestation crates and well-designed, well-managed gestation pens will have the best accommodation available for each sow in the herd.

Reference - non refereed

Blackwell TE. Exceeding expectations. Proc AASV. Kansas City, Missouri. 2002; 9-18.

--Cate Dewey

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