The feeding of dried distillers' grains with solubles to lactating sows

A meta-regression analysis to evaluate the influence of branched-chain amino acids in lactation diets on sow and litter growth performance

The branched-chain amino acids (BCAA) Ile, Leu, and Val are three dietary essential amino acids for lactating sows; however, effects of dietary BCAA on sow and litter growth performance in the literature are equivocal. Thus, a meta-regression analysis was conducted to evaluate the effects of BCAA and their interactions in lactating sow diets to predict litter growth performance, sow bodyweight change, and sow feed intake. Thirty-four publications that represented 43 trials from 1997 to 2020 were used to develop a database that contained 167 observations. Diets for each trial were reformulated using NRC. 2012. Nutrient requirements of swine. 11th ed. Washington, DC: National Academies Press nutrient loading values in an Excel-based spreadsheet. Amino acids were expressed on a standardized ileal digestible (SID) basis. Regression model equations were developed with the MIXED procedure of SAS (Version 9.4, SAS Institute, Cary, NC) and utilized the inverse of reported squared SEM with the WEIGHT statement to account for heterogeneous errors across studies. Predictor variables were assessed with a step-wise manual forward selection for model inclusion. Additionally, statistically significant (P < 0.05) predictor variables were required to provide an improvement of at least 2 Bayesian information criterion units to be included in the final model. Significant predictor variables within three optimum equations developed for litter ADG included the count of weaned pigs per litter, NE, SID Lys, CP, sow ADFI, Val:Lys, Ile:Lys, and Leu:Val. For sow BW change, significant predictor variables within two developed models included litter size at 24 h, sow ADFI, Leu:Lys, and Ile + Val:Leu. The optimum equation for sow ADFI included Leu:Trp, SID Lys, NE, CP, and Leu:Lys as significant predictor variables. Overall, the prediction equations suggest that BCAA play an important role in litter growth, sow BW change, and feed intake during lactation; however, the influence of BCAA on these criteria is much smaller than that of other dietary components such as NE, SID Lys, sow ADFI, and CP.

The influence of dietary corn distillers dried grains with solubles during gestation of sows on fatty acid composition of colostrum and offspring

Thirty-six sows were randomly assigned to three treatments and fed 0, 125, or 250 g kg−1 corn distillers dried grains with solubles (DDGS), which aimed to evaluate the effects of feeding DDGS to sows during gestation on the fatty acid composition of colostrum and offspring. In colostrum, feeding 0–250 g kg−1 DDGS resulted in linear increase (P < 0.001) in linoleic acid (18:2n-6) level (from 14.7% to 19.8%) and total polyunsaturated fatty acid (PUFA) level (from 16.9% to 22.8%), and linear decrease (P < 0.05) in levels of palmitic acid (16:0), oleic acid (18:1 cis-9), and total saturated fatty acid (SFA). In addition, the percentage of arachidonic acid (20:4n-6) in colostrum was increased from 0.56% to 1.23% (linear effect, P < 0.001, and quadratic effect, P = 0.010) with increasing level of DDGS. Feeding DDGS to sows resulted in linear increase (P < 0.05) in levels of 18:2n-6 (from 13.9% to 20.4%), 20:4n-6 (from 0.53% to 0.73%), docosahexaenoic acid (22:6n-3, from 0.28% to 0.37%), and total PUFA (from 15.9% to 22.6%), and linear decrease (P < 0.001) in levels of 16:0 and SFA of carcass of newborn piglets. The results demonstrated that feeding 125 or 250 g kg−1 corn DDGS to sows increased the proportions of 18:2n-6, 20:4n-6, and total PUFA and decreased the proportions of 16:0 and total SFA in sow colostrum and the carcasses of newborn piglets, implying that inclusion of corn DDGS in diets for sows can alter fatty composition of colostrum and piglets.

Evaluation of the optimal standardized ileal digestible tryptophan:lysine ratio in lactating sow diets

Three hundred and fifteen primiparous and multiparous sows were evaluated in a study to determine the effect of standardized ileal digestible (SID) Trp:Lys ratio in lactating sow diets. Camborough sows (PIC USA, Hendersonville, TN) ranging from first parity to eighth parity were blocked by parity and randomly allotted to 1 of 4 experimental diets containing different levels of added L-Trp (0.006, 0.026, 0.045, and 0.064%, respectively) while soybean meal, 30% corn dried distiller's grain with solubles (DDGS), and L-Lys levels were held constant. The SID Lys level for the rations was 0.95% so that the SID Trp:Lys ratios were formulated to be 14, 16, 18, and 20%, respectively. All diets were formulated to have 3.2 Mcal ME/kg and to contain vitamins and minerals that exceeded NRC (1998) recommendations. Sows were fed twice a day with a Howema computerized feed system and were allowed a maximum intake (5.9 kg/d). Average daily feed intake had a tendency to be quadratically improved when the SID ratio was increased (5.11, 5.28, 5.24, 5.21 kg/d, P = 0.09). In addition, sow wean to estrus (6.71, 5.53, 5.58, 6.33, P < 0.02) was quadratically improved as SID Trp:Lys ratio increased. Percent of sows bred by 10 d (84.39, 90.82, 90.28, 90.61) was not linearly (P = 0.25) or quadratically (P = 0.40) improved. There was no difference in litter gain (2.44, 2.52, 2.60, 2.57 kg/d, P = 0.16). Based on a broken-line quadratic model, when sows are fed 30% DDGS, the SID Trp:Lys ratio of 17.6 is required for optimal sow average daily feed intake and 17.2 for wean to estrus interval.