The initiation of lactation in sows and the mastitis-metritis-agalactia syndrome

The initiation of lactation was studied in 46 sows farrowing normally in a commercial piggery practising intensive swine husbandry. Eleven of these sows showed typical clinical symptoms of mastitis-metritis-agalactia (MMA) syndrome, 12–48 h after parturition. Mammary secretion was collected from all sows at farrowing and analysed for lactose, protein, fat, Na⁺ and K⁺. The sows which subsequently developed MMA had significantly higher concentrations of lactose and significantly lower concentrations of protein and Na⁺ in colostrum, compared to normal sows.Analysis of milk from MMA sows showed an altered composition of milk (increased Na⁺ and decreased K⁺ and lactose concentrations). Results from this study suggest that an early initation of lactation resulting in the engorgement of the mammary glands predisposes the sows to MMA. Analysis of mammary secretion may be used to identify affected glands.