A total of 727 mixed parity (µ = 3.8) sows were used to evaluate the effects of timing and size of meals before farrowing on sow and litter performance. Upon entry to the farrowing house (day 113), sows were blocked by weight within parity and allotted to one of three three feeding management strategies until farrowing: (1) 2.7 kg lactation diet (1.15% standardized ileal digestible lysine and 2,153 kcal/kg net energy) once daily at 0700 hours; (2) four daily meals of 0.67 kg (0100, 0700, 1300, and 1900 hours); (3) ad libitum lactation diet and encouraged to consume feed at 0100, 0700, 1300, and 1900 hours. After farrowing, all sows were provided lactation diets fed on an ad libitum basis until weaning. Data were analyzed for treatment effects within parity category in a mixed model with block as a random effect. Feeding sows ad libitum before farrowing tended to reduce sow body weight (BW) loss (P = 0.077) and reduce backfat (BF) loss (P = 0.003) from entry into the farrowing house until weaning compared with sows fed four daily meals, with sows fed once daily intermediate. Litter gain from 24 h to weaning tended to be greater (P = 0.073) in sows fed on an ad libitum basis or four times daily prior to farrowing compared with sows fed one meal. Piglet weaning weight increased (P = 0.050) in sows fed on an ad libitum basis before farrowing, compared with those fed one meal, with those fed four times daily intermediate. There was no evidence for difference in farrowing duration, stillborn rate, colostrum yield, or 24 h piglet survival regardless of treatment. However, from 24 h after farrowing to weaning, sows fed one daily meal prior to farrowing had an increased (P = 0.012) percentage of fall-behind pigs compared with sows fed on an ad libitum basis, and increased (P = 0.027) preweaning mortality compared with sows fed four daily meals, resulting in reduced (P = 0.006) weaned percentage compared with sows fed four daily meals. There was no evidence for difference (P > 0.10) in subsequent reproductive performance regardless of treatment. In conclusion, when sows were fed on an ad libitum basis from 2 to 3 d, before farrowing there was an observed improvement in sow BW and BF maintenance during lactation, and piglet weaning weight during lactation. Increased frequency of meals prior to farrowing improved the survival of pigs to weaning compared with sows fed a single meal prior to farrowing.

A total of 727 mixed parity (mean=3.8) sows were used to evaluate the effects of timing and amount of meals before farrowing on sow and litter performance. Upon entry to the farrowing house (d 113), sows were blocked by weight within parity and allotted to one of three feeding management treatments until farrowing: 1) 2.7 kg lactation diet (1.15% SID lysine and 2,153 Kcal/kg NE) once daily at 0700 h; 2) 4 daily meals of 0.67 kg (0100 h, 0700 h, 1300 h, 1900 h); 3) ad libitum lactation diet and encouraged to consume feed at 0100 h, 0700 h, 1300 h, and 1900 h. Data was analyzed using the lme function (lmer package of R, version 3.5.2). Feeding sows ad libitum before farrowing tended to reduce sow body weight loss (P=0.077) and reduce backfat loss (P=0.003) from entry to weaning compared to sows fed 4 daily meals, with sows fed once daily intermediate. Litter gain from 24 h to weaning tended to be greater (P=0.073) in sows fed ad libitum or 4 times daily prior to farrowing compared to sows fed one meal. Piglet weaning weight increased (P=0.050) in sows fed ad libitum before farrowing, compared to those fed one meal, with those fed 4 times daily intermediate. There was no evidence for difference in farrowing duration, stillborn rate, colostrum yield, or 24 h piglet survival regardless of treatment. However from 24 h to weaning, sows fed one daily meal had higher (P=0.012) percentage of fall-behind pigs compared to sows fed ad libitum, and increased (P=0.027) preweaning mortality compared to sows fed four daily meals, resulting in reduced (P=0.006) weaned percentage compared to sows fed four daily meals. There was no evidence for a negative impact when sows were fed ad libitum from 2 to 3 days before farrowing.

Dietary cation-anion difference (DCAD), calculated as Na + + K + – Cl - in mEq/kg of the diet, represents the influence that monovalent cations and anions from these minerals have on the acid-base status of the animal. However, the recommended range of DCAD for optimal grow-finish swine performance is variable, which may indicate an interaction between DCAD and other ingredients. The hypothesis for this study was that the addition of potassium bicarbonate (KHCO3) to increase diet DCAD when high levels of L-Lys HCl (> 0.35% diet) are used may potentially improve growth performance. A total of 1,944 pigs (PIC L337 × 1050, initially 35.2 ± 0.85 kg) were used in a 120-d study. Pens of pigs were blocked by BW and randomly allotted to 1 of 4 dietary treatments in a randomized complete block design. Treatments were arranged in a 2 × 2 factorial with main effects of KHCO3 (0 or 0.4%), and L-Lys HCl level (low or high). L-Lys HCl was included between 0.13 and 0.21% in low diets, and between 0.36 and 0.43% in high diets. There were 27 pigs per pen and 18 replicates per treatment. Treatment diets were corn-soybean meal-based and formulated in four dietary phases (35 to 60 kg, 60 to 85 kg, 85 to 105 kg, and 105 to 130 kg). Dietary treatments were formulated such that in each phase the diet containing a low level of L-Lys HCl without KHCO3 and the diet containing a high level of L-Lys HCl with KHCO3 had similar calculated DCAD values (169 to 232 mEq/kg). Additionally, the diet with a low level of L-Lys HCl with KHCO3 was formulated to have the highest DCAD in each phase (220 to 281 mEq/kg), while the diet with a high level of L-Lys HCl without KHCO3 was formulated to have the lowest DCAD (118 to 182 mEq/kg). Overall, there was no evidence (P > 0.10) for a KHCO3 × L-Lys HCl interaction or main effect for final BW or any observed growth response or carcass characteristics. The results of this study suggest that supplementing KHCO3 to finishing pig diets with either high or low levels of L-Lys HCl and the corresponding changes in DCAD values did not impact growth performance or carcass characteristics.

This experiment was conducted to evaluate the influence of vegetable protein sources on growth performance of nursery pigs in a commercial research environment. A total of 2,592 pigs (L337 × 1050, PIC; initial BW of 5.3 ± 0.05 kg) were used in a 42-d study. Pens of pigs were blocked by BW and weaning date and allotted to 1 of 6 dietary treatments in a randomized complete block design with 27 pigs/pen and 16 replications/treatment. A corn-soybean meal control diet with no specialty vegetable protein source was used to compare performance against 5 diets containing either 1 of 2 soy protein concentrates (XSoy 600; CJ America-Bio, Downers Grove, IL; 5.0 and 2.5%, phase 1 and 2, respectively or Soytide; CJ America-Bio, Downers Grove, IL; 5.5 and 2.75%, phase 1 and 2, respectively), enzyme-treated soybean meal (HP 300; Hamlet Protein, Findlay, OH; 5.7 and 2.83%, phase 1 and 2, respectively), fermented soybean meal (Fermex 200; Purina Animal Nutrition, Shoreview, MN; 6.7 and 3.35%, phase 1 and 2, respectively), or high-protein corn DDGs (NexPro; Poet, Wichita, KS; 7.5 and 3.75%, phase 1 and 2, respectively). Diets were formulated in 2 dietary phases and fed at 2.27 kg/pig and 8.16 kg/pig, respectively, with a common phase 3 diet fed until d 42. The dietary level of soybean meal was held constant within phases 1 and 2 for diets 2 to 5 with protein sources replaced on a digestible lysine basis. During the experimental diet period (d 0 to 21) or overall (d 0 to 42), there was no evidence of difference (P > 0.05) for ADG, ADFI or G:F. Additionally, there was no evidence of difference (P > 0.05) for total removals, and mortality. In summary, none of the protein sources evaluated improved growth performance relative to soybean meal.

Two studies were conducted to estimate the SID Lys requirement for growth and feed efficiency of 70-130-kg DNA finishing pigs. In Exp. 1, 616 pigs (600×241, DNA; initially 76.4±1.25 kg) were used from 70-100-kg and in Exp. 2, 679 pigs (600×241, DNA; initially 103.8±1.32 kg) were used from 100-130 kg. Pens of pigs were blocked by BW and randomly allotted to dietary treatments with 8-10 pigs/pen in a randomized complete block design. Diets were corn-soybean meal based and SID Lys increased by increasing soybean meal and feed-grade amino acids while maintaining minimum ratios for other amino acids. From 70-100 kg, ADG, G:F, Lys intake/d, and Lys intake/kg of gain all increased, (linear, P < 0.05) with increasing SID Lys. From 100-130 kg, ADG, Lys intake/d, and Lys intake/kg of gain increased (linear, P < 0.05) with increasing SID Lys, while G:F increased (quadratic, P = 0.032). At current ingredient and pig prices, there were no statistical differences in income over feed cost (IOFC) from 70-100 kg. From 100-130 kg, increasing SID Lys increased (quadratic, P = 0.001) IOFC. A broken-line linear (BLL) model predicted optimal ADG at 0.83% SID Lys, while a quadratic polynomial (QP) model predicted a requirement of 0.90% for G:F from 75-100 kg. A QP model predicted maximum IOFC at 0.78% SID Lys from 75-100 kg. From 100-130 kg, BLL models predicted optimal ADG and G:F at 0.64 and 0.59% SID Lys, respectively. A QP model predicted maximum IOFC at 0.64% SID Lys. In summary, these results suggest the optimal SID Lys level for 75-100 kg DNA finishing pigs for growth performance is between 0.83 and 0.90% SID Lys, and 0.78% SID Lys for maximum IOFC. The optimal SID Lys level in 100-130 kg DNA finishing pigs depends upon the response criteria, with growth performance and IOFC maximized between 0.59 and 0.64% SID Lys.