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The impact of supplemental choice white grease on sows and litter performance when fed during lactation
Four hundred and fourteen sows (PIC-C29) were blocked by parity (range of 1 – 5, avg 2.7 ± 0.7), breeding group, and body weight to determine the impact of increased dietary energy (ME) fed through supplemental choice white grease (CWG) on lactating sow and litter performance. Treatments consisted of 0, 2, 4, or 6% added CWG (8,124 kcal/kg ME), respectively. Diets were formulated to a standardized ileal digestible (SID) lysine to ME ratio of 3.34 g/Mcal with 1.05, 1.08, 1.11, 1.15% SID lysine, respectively and contained 20% corn distillers dried grain solubles (DDGS). Litters were standardized within rep by 24 hr post-farrow (12.6 ± 0.6 pigs). Lactation length averaged 19 d. Trial was conducted from May to September. No treatment × parity interactions (P > 0.05) were observed in this trial. Sow weaning weight (233.1, 233.3, 237.5, and 242.8 kg, respectively) and lactation weight change (9.5, 12.0, 14.2, and 17.9 kg, respectively) increased linearly (P < 0.001) and total weight change (-11.6, -11.6, -6.4, and -4.7 kg, respectively) decreased linearly (P = 0.001) with increasing levels of added fat. Average daily feed intake (7.1, 7.3, 7.2, and 7.3 kg/d, respectively) and wean-to-estrus interval (4.98, 4.96, 5.00, and 5.01 d, respectively) were not impacted (P > 0.50) by added fat level. The number of pigs weaned /litter (12.0, 11.9, 12.0, and 12.0, respectively), piglet weaning weight (6.3, 6.4, 6.4, 6.5 kg, respectively), piglet ADG (251, 250, 252, 259 g/d, respectively), and pre-wean mortality (4.3, 5.1, 4.2, and 4.9%, respectively) were not impacted (P > 0.35) by the level of added fat in the sow diet. Sow G:F [defined as: (sow lactation weight change + litter gain)/total sow feed intake] increased linearly (0.52, 0.52, 0.54, and 0.57, respectively; P < 0.001) with increasing level of added fat in the diet. Conversely, litter G:F [defined as: litter gain/total sow feed intake] was not impacted (P= 0.82) by added fat level. These data would suggest that in high feed intake sows, the addition of added fat to the diet does not affect sow feed intake or piglet performance. It would appear that the additional energy intake is utilized by the sow to increase weight gain during lactation and is not partitioned towards increased milk production.
Keywords: sow, fat, lactation