218 Simple Blending of Gestation and Lactation Diets During the Transition Period Minimizes Losses in Back Fat Depth Around Parturition for Primi and Multiparous Sows

Abstract

Abstract Fifty of each primiparous and multiparous sows were used to evaluate a blending feeding program using gestation and lactation diets during the transition period on sow back fat depth (BF), blood metabolites, and litter growth performance. Sows were randomly assigned to one of two feeding programs in a 2×2 factorial design (n = 25) from 104 ± 1 days of gestation: 1) a unique daily blend of standard gestation [0.58% standardized ileal digestible (SID) lysine and 2419kcal/kg NE] and lactation diets (0.95% SID lysine and 2507kcal/kg NE) until day 5 after farrowing to meet estimated daily SID lysine and net energy requirements (NRC, 2012; TRAN) or 2) approximately 2 kg per day of a standard lactation diet until farrowing (CON). Upon farrowing, sows on the CON feeding program received step-up access to the lactation diet according to a feeding curve. Five days after farrowing, both groups received ad libitum access to the lactation diet until weaning (20.0 ± 0.3 days). Sow body weight (BW) and BFwere measured on day 104 and 110 of gestation (BW only), after farrowing, and at weaning. Fasted blood samples were collected from sows at farrowing and weaning. Litters were standardized to 13 ± 1 piglets and were not provided creep feed. During gestation, TRAN sows consumed more feed than CON sows, which was especially evident for multiparous sows (2.95 vs. 2.13 ± 0.08kg/d for TRAN vs. CON; interaction and main effect; P < 0.05). During lactation, average daily feed intake was not influenced by feeding program but was greater for multi versus primiparous sows (5.98 vs. 4.20 ± 0.30kg; P < 0.001). At all time points, BW was greater for multi versus primiparous sows, regardless of feeding program (P < 0.05). During the gestation period, TRAN sows tended to have greater average daily gain (1.43 vs. 1.00±0.39kg/d; P=0.061) and had less back fat loss (-0.18 vs. -0.92 ± 0.37mm; P < 0.05) versus CON sows, regardless of parity. Only after farrowing, TRAN sows had greater BW and BF than CON sows, regardless of parity (221.5 vs. 215.5 ± 4.1kg and 17.0 vs. 16.3 ± 0.4mm; P < 0.05), but at weaning there were no feeding program-related differences in BW or BF. No feeding program-related differences were observed for litter characteristics, but litter birth weight and piglet BW at weaning were greater for multi versus primiparous sows (P< 0.01). Only after farrowing, serum BHBA (11.9 vs. 19.4 ± 7.8mmol/L) and NEFA (0.34 vs. 0.56 ± 0.10mmol/L) concentrations were less and serum glucose concentrations (4.4 vs. 3.9 ± 0.2mmol/L) were greater for TRAN versus CON sows (P < 0.05), regardless of parity. Therefore, a simple transition feeding program using standard gestation and lactation diets reduced energy mobilization by multi and primiparous sows in late gestation, with no impact on subsequent lactation performance.