PSVI-19 Impact of Sow Body Condition on Macro Reproductive Performance

Abstract Sow body condition is important for maximizing life-time productivity, milk production and progeny performance. Data from a total of 4,367 sows (76PIC, 4291Genesus) were used to investigate relationships between sow body condition at entry to farrowing house (body weight, back fat, body condition score) versus reproductive performance and milk production. Data were from a commercial farm from 2018-2020. Sow data were stratified by parity: Class 1 (parity 1), 2 (parity 2-4) and 3+ (parity 4 and above). Sow entry weight (with fetuses), backfat, and body condition score (scale 1-5) were measured at entry to farrowing house and at weaning. Milk production was calculated using the method of Hansen et al. (2012). Standard sow performance was collected via data software (Agriness). Data were plotted and assessed for commercially relevant relationships among dependent and independent variables. Single factor linear regression was used to calculate linear slope and slope standard error between variables of interest within parity. The farm represents typical north American performance with average piglets born alive13.9, total piglets born 15.6, number of piglets weaned 10.5. Regardless of parity, sow body weight at entry had the greatest positive linear relationship to reproductive productivity. Heavier weight at entry was positively related to number of total piglets born, born piglets alive, litter birth weight and milk production. Heavier primiparous sows at entry had greater piglet weight gain and weaning weight. A positive linear relationship (evidenced by non-zero linear slope) was observed between sow back fat loss and milk production in primiparous sows. Relationships among sow back fat, body condition score and productivity were weak (confidence interval of slope included zero). Sow backfat at entry did not impact lactation feed intake. This might be due to high average lactation feed intake (average 8 kg/d) in this farm. Slightly positive regression was observed between sow weight and lactation intake in primiparous sows but not in older sows. Most commercial farms do not have weighing equipment. Sow body condition score is often used as an economic method but highly variable depending on farm personnel. Our investigation suggests that sow body weight is important for sow reproductive performance. Gilt body weight at entry is positively related to litter birth weight and weaning weight. Future research is needed to better understand sow body composition (fat and lean percentage) on productivity and find economic ways to collect these parameters at commercial farms.