PSII-26 Early- and mid- lactation milk traits are associated with piglet growth during lactation

Preweaning piglet growth is tied to milk quality and consumption. To determine the relationship of milk components from parity 1–4 dams and piglet growth, early and mid-lactation (d 2 and 16) milk samples were collected from 48 litters and analyzed for protein, fat, somatic cell count, lactose, solids, total solids, and milk urea nitrogen. Each milk trait was categorically identified at 25, 50 or 75 percentiles as low, moderate, or high, respectively. Mixed models (SAS); dam repeated, sire random, and adjusted for parity and litter size; were used to determine association of individual milk traits with piglet lactation growth (gain calculated from body weights at birth, d10, and weaning; WN). Moderate levels of d2 milk protein were associated with the greatest gain during lactation in comparison to low and high levels (Table 1). High levels of d2 milk lactose and d2 solids were both related to piglet gain over the lactation period (Table 1). Evaluation of d16 milk traits with piglet gain over lactation indicated high levels of d16 fat, d16 solids, and d16 total solids had the greatest gain in comparison to moderate and low levels of each trait (Table 1). Within phase of lactation weight gain, association of d2 or d16 milk traits with early weight gain (birth to d10) or late weight gain (d10 to WN) were performed. The greatest early lactation gains (birth to d10) were associated with moderate levels of d2 protein, high levels of d2 lactose and d2 solids, and low levels of d2 MUN (Table 2). High levels of milk fat, lactose, and solids at d2 were associated with piglet gain during late lactation (d10 to WN; Table 3). In general, greater levels of lactose in d2 milk and fat in d16 milk were associated with piglet gain during lactation.