Effects of a cheese co-product fed in lactation and nursery diets on sow, litter, and subsequent nursery pig performance

A total of 86 sows (Line 241, DNA Genetics, Columbus, NE) were used to determine the effects of a cheese co-product added to lactation diets on sow and litter performance. Sows in three separate farrowing groups (approximately 31 ± 1 sows per group) were moved into the farrowing house and blocked by parity on d 112 ± 1 of gestation. Sows then were assigned to one of two dietary treatments which consisted of a standard corn-soybean-based lactation diet (control) or the control diet with 4% cheese co-product (Pro88; Keys Manufacturing, Paris, IL, USA) added at the expense of soybean meal on a digestible Lys-basis. The addition of the cheese co-product in lactation diets did not affect sow or litter performance. Offspring from the third farrowing group (395 pigs; DNA Line 241 × 600; initially 5.8 kg) were followed into the nursery and used in a 2 × 2 factorial to evaluate the effects of previous sow lactation feed treatment and addition of the cheese co-product in nursery diets in a 35-d growth trial. Nursery treatments included either a control diet or the control diet with 4% added cheese co-product fed in phases 1 (d 0 to 9) and 2 (d 9 to 21) followed by a common diet fed to all pigs in phase 3 (d 21 to 35). The cheese co-product was added at the expense of enzyme treated soybean meal in the nursery diets on a digestible Lys-basis. No sow × nursery interactions were observed. Offspring from the third group of sows fed the cheese co-product were heavier (P < 0.001) at weaning than those not fed cheese co-product, and this body weight advantage was maintained throughout the experiment. There was a tendency (P = 0.058) for fewer pigs fed the cheese co-product in the nursery to lose body weight from d 0 to 3 after weaning, regardless of previous sow treatment. During the nursery experimental period (d 0 to 21 post-weaning) and overall (d 0 to 35), pigs weaned from sows fed the cheese co-product tended to have increased (P < 0.10) gain-to-feed ratio (G:F). There were no effects on average daily gain or feed intake due to previous sow treatment. In addition, during the experimental period and overall, feeding the cheese co-product in the nursery diet increased (P < 0.05) G:F compared with pigs fed the control diet. In conclusion, feeding a cheese co-product either in lactation or early nursery diets at the expense of soybean meal or a specialty soy protein, respectively, increased G:F of pigs throughout the nursery period.