Spring 2025 www.pigchamp.com 29 Today’s modern hyper-prolific sow will often give birth to more piglets than the number of functional teats she possesses. For the farm business, it means that the producers are faced with the decision of having to either allow the sow to try and nurse the additional piglets above functional teat count or create more nurse sows. Nurse sows are females who have just weaned a litter of their own and are then moved into a new room to support the additional pigs born above the teat count. The potential drawbacks of having high nurse sow usage include: · No additional colostrum intake for pigs cross- fostered onto her; · Increased risk of disease transmission when moving sows between farrowing rooms, and; · Decreased breeding targets as empty crates are needed to make room for nurse sows. If we have a hyperprolific female but want to limit nurse sow usage, we must first consider the impact of having more pigs than functional teats. How will it impact pre-weaning mortality, fall-behind pigs, piglet growth, sow body condition, or any subsequent reproduction efforts? In an effort to answer these questions, a recent study was conducted at a commercial sow farm in northwest Texas. A total of 1,005 sows (average parity 3.5, PIC Line 1050) and their litters (15,278 piglets) were utilized to determine the impact of litter size relative to teat count on sow lactation measurements, litter performance, and subsequent reproductive performance under commercial conditions. Sows were allocated piglets according to four treatments with: 1. One fewer pig than functional teats (-1); 2. The same number of pigs as functional teats (0); 3. One more pig than functional teats (+1); 4. Two more pigs than functional teats (+2). In the context of this study, a functional teat is any teat that produces enough milk to sustain the life of a piglet. Therefore, any blunt teats, blind teats, and teats connected to mammary glands with severe edema were considered non-functional. The average functional teat count in this study was 14.7 teats. Measurements of sow body condition (body weight, backfat depth, and caliper score) were collected at the time of loading into the farrowing house (day 112 of gestation) and at weaning. After each sow was done farrowing, she was randomly assigned to a treatment such that functional teat count, parity, and sow body condition were equalized across all treatments. Any pigs born weighing less than two lbs. were not included in this study, as they were cross-fostered into litters receiving specialized care as per the normal standard operating procedure of this farm. To attain the correct number of pigs relative to functional teat count, average birth weight pigs were cross-fostered to maintain the normal body weight variation within the litter and to keep the average piglet starting weight across all four treatments the same (3.4 lbs.). Pigs were individually weighed after cross-fostering was complete for that litter and on the day before weaning. The average weaning age of this trial was 22 days. No supplemental nutrition (creep or milk) was provided to any of the litters in this study. Starting at day 3 of lactation, fall-behind pigs were identified and SHOULD A SOW NURSE? How Many Pigs The effect of litter size relative to functional teat count on lactating sow and litter performance. Researchers: Abigail Jenkins, Sierra Collier, Joel DeRouchey, Mike Tokach, Jason Woodworth, Katelyn Gaffield, Jordan Gebhardt, and Robert Goodband, all of Kansas State University Photo courtesy of Kansas State University
RkJQdWJsaXNoZXIy NTc0MDI3