Production and composition of sow milk

Sammanfattning: Colostrum and milk yield and composition are important for piglet survival and growth Mammogenesis occurs during prepuberty, puberty, gestation and lactation. Colostrogenesis starts before parturition and transcends into lactogenesis 24-36 hours after parturition. If the teats are not suckled, involution will occur. The piglets start to suckle from 20-30 minutes after birth, nurses almost once every hour both day and night and the milk let down is ten to 20 seconds per nursing time. Colostrum yield is roughly around four kg during the first 24 hours after parturition. Milk yield is roughly around nine kg/day. Yield is difficult to measure. The sow reaches peak lactation at around day 12. The semi-natural length of sow lactation is 17 weeks but the length of lactation in production systems ranges from two to five weeks. Colostrum has a higher DM, CP and whey protein content than milk. This is due to the high amount of immunoglobulins in colostrum. Mature milk has a higher content of lactose, fat and caseins than colostrum. Factors that affect yield and composition are genetics, feeding strategies, sow health, parity number, weight of the sow, litter size, total litter weight and mean piglet birth weight.