Reproductive performance among sows group-housed during late lactation

Area of Science:

• Animal Science
• Reproductive Biology
• Swine Production

Background:

• Traditional individual penning of sows during lactation is common practice.
• Group housing systems for sows are being explored as an alternative management strategy.

Purpose of the Study:

• To compare the reproductive performance of sows housed in group versus individual pens during lactation.
• To identify potential impacts of group housing on sow fertility and culling rates.

Main Methods:

• A comparative study involving four group-housing farms (G-farms) and three control farms (C-farms) with individual pens.
• Data collection on fertility and culling for 16 months, including litter size, mating success, and repeat breeder frequency.
• Sows were crossbred Swedish Yorkshire x Swedish Landrace, housed in groups in breeding and deep-litter dry-sow sections.

Main Results:

• Older sows (> or = 5th parity) in G-farms had significantly smaller litter sizes (p = 0.02).
• A lower percentage of sows were mated within 10 days post-weaning in G-farms (p < 0.001), especially older sows.
• Multiparous sows in G-farms exhibited a higher frequency of repeat breeders (p = 0.04).
• Repeat breeding was a common reason for culling in G-farms.

Conclusions:

• Group housing of sows during lactation appears to impair reproductive performance.
• Potential contributing factors include difficulties in oestrous detection due to lactational oestrus in group settings.
• Management strategies may need adjustment for group-housed sows to optimize reproductive outcomes.