Two studies were designed to determine the effects of supplementing diets with lipid sources of EFA (linoleic and α-linolenic acid) on sow milk composition to estimate the balance of EFA for sows nursing large litters. In Exp. 1, 30 sows, equally balanced by parity (1 and 3 to 5) and nursing 12 pigs, were fed diets supplemented with 6% animal-vegetable blend (A-V), 6% choice white grease (CWG), or a control diet without added lipid. Diets were corn-soybean meal based with 8% corn distiller dried grains with solubles and 6% wheat middlings and contained 3.25 g standardized ileal digestible Lys/Mcal ME. Sows fed lipid-supplemented diets secreted greater amounts of fat (P = 0.082; 499 and 559 g/d for control and lipid-added diets, respectively) than sows fed the control diet. The balance of EFA was computed as apparent ileal digestible intake of EFA minus the outflow of EFA in milk. For sows fed the control diet, the amount of linoleic acid secreted in milk was greater than the amount consumed, throughout lactation. This resulted in a pronounced negative balance of linoleic acid (-22.4, -38.0, and -14.1 g/d for d 3, 10, and 17 of lactation, respectively). In Exp. 2, 50 sows, equally balanced by parity and nursing 12 pigs, were randomly assigned to a 2 × 2 factorial arrangement of diets plus a control diet without added lipids. Factors included linoleic acid (2.1% and 3.3%) and α-linolenic acid (0.15% and 0.45%). The different concentrations of EFA were obtained by adding 4% of different mixtures of canola, corn, and flaxseed oils to diets. The n-6 to n-3 fatty acid ratios in the diets ranged from 5 to 22. Increasing supplemental EFA increased (P < 0.001) milk concentrations of linoleic (16.7% and 20.8%, for 2.1% and 3.3% linoleic acid, respectively) and α-linolenic acid (P < 0.001; 1.1 and 1.9% for 0.15 and 0.45% α-linolenic acid, respectively). Increasing supplemental EFA increased the estimated balance of α-linolenic acid (P < 0.001; -0.2 and 5.3 g/d for 0.15% and 0.45% α-linolenic acid, respectively), but not linoleic acid (P = 0.14; -3.4 and 10.0 g/d for 2.1% and 3.3% linoleic acid, respectively). In conclusion, lipid supplementation to sow lactation diets improved milk fat secretion. The fatty acid composition of milk fat reflected the dietary supplementation of EFA. The net effect of supplemental EFA was to create a positive balance during lactation, which may prove to be beneficial for the development of nursing piglets and the subsequent reproduction of sows.

The present study was designed to evaluate the effects of dietary betaine on pig performance and serological and hematological indices during thermoneutral and heat-stressed conditions. Individually housed pigs ( = 64; 39.0 ± 1.5 kg BW) were assigned within weight blocks and sex to 1 of 8 treatments. Treatments consisted of 2 environmental conditions (thermoneutral or heat-stressed) and 4 levels of betaine (0, 0.10, 0.15, and 0.20%). Room temperatures followed a daily pattern with a low of 14°C and a high of 21°C for the thermoneutral environment and a low of 28°C and a high of 35°C for the heat-stressed environment. Experimental diets were fed from d -7 (7 d prior to imposing temperature treatments; constant 21°C) until 28. Respiration rate and rectal temperature were measured on d 0, 1, 2, 3, 7, 14, 21, and 28, and blood samples were collected on d 3 and 28. Heat stress reduced ( ≤ 0.008) ADG (0.710 vs. 0.822 kg/d) and ADFI (1.81 vs. 2.27 kg/d) and increased G:F ( = 0.036; 0.391 vs. 0.365). Betaine tended to quadratically increase G:F ( = 0.071; 0.377, 0.391, 0.379, and 0.366 for 0, 0.10, 0.15, and 0.20% betaine, respectively), regardless of environment. Heat stress increased ( ≤ 0.001) respiration rate (48 vs. 23 breaths/30 s) and rectal temperature (39.47 vs. 38.94°C) throughout d 1 to 28. Betaine at 0.10% reduced rectal temperature in heat-stressed pigs but not in control pigs (interaction, = 0.040). Heat stress increased serum cysteine and triglycerides and reduced Ca, alkaline phosphatase, and lipase, regardless of day of sampling ( ≤ 0.048). Heat stress increased serum creatine phosphokinase (CPK) and K and reduced osmolarity, Na, urea N, methionine, homocysteine, the albumin:globulin ratio, and blood eosinophil count on d 3 but not on d 28 (interaction, ≤ 0.013). Heat stress increased serum Mg, globulin, creatinine, amylase, and γ-glutamyltranspeptidase and reduced , the urea N:creatinine ratio, alanine aminotransferase, NEFA, hemoglobin, hematocrit, and red blood cells on d 28 but not on d 3 (interaction, ≤ 0.034). Betaine increased serum osmolarity and NEFA and reduced CPK and K on d 3 but not on d 28 (interaction, ≤ 0.060) and increased serum creatinine and reduced amylase on d 28 but not on d 3 (interaction ≤ 0.057). Heat stress reduced growth, disturbed ion balance, and increased markers of muscle damage. Betaine had a minor impact on alleviating heat stress with the possible exception of early days of heat exposure. The beneficial effect of betaine was diminished by pig adaptation.

Acidulated fats and oils are by-products of the fat-refining industry. They contain high levels of FFA and are 10% to 20% less expensive than refined fats and oils. Two studies were designed to measure the effects of dietary lipid sources low or high in FFA on growth performance and apparent total tract digestibility (ATTD) of lipids and GE in nursery pigs. In Exp. 1, 189 pigs at 14 d postweaning (BW of 9.32 ± 0.11 kg) were used for 21 d with 9 replicate pens per treatment and 3 pigs per pen. Dietary treatments consisted of a control diet without added lipids and 6 diets with 6% inclusion of lipids. Four lipid sources were combined to create the dietary treatments with 2 levels of FFA (0.40% or 54.0%) and 3 degrees of fat saturation (iodine value [IV] = 77, 100, or 123) in a 2 × 3 factorial arrangement. Lipid sources were soybean oil (0.3% FFA and IV = 129.4), soybean-cottonseed acid oil blend (70.5% FFA and IV = 112.9), choice white grease (0.6% FFA and IV = 74.8), and choice white acid grease (56.0% FFA and IV = 79.0). Addition of lipid sources decreased ADFI (810 vs. 872 g/d; P = 0.018) and improved G:F (716 vs. 646 g/kg; P < 0.001). Diets high in FFA tended (P = 0.08) to improve final BW (21.35 vs. 21.01 kg) and ADG (576 vs. 560 g/d). Lipid-supplemented diets had greater ATTD of lipids than control diets (67.4% vs. 29.7%; P < 0.001). Apparent total tract digestibility of lipids was greater in diets with low FFA (69.9% vs. 64.9%; P < 0.001) and decreased linearly with increasing IV (73.2%, 69.1%, and 67.2%). For GE, ATTD was greater in diets with low FFA (83.1% vs. 80.9%; P = 0.001). In Exp. 2, 252 pigs at 7 d postweaning (BW of 7.0 ± 0.2 kg) were used for 28 d with 9 replicate pens per treatment and 4 pigs per pen. Diets included a control diet without added lipids and 6 treatments with 2.5%, 5.0%, or 7.5% of lipids from either poultry fat (1.9% FFA) or acidulated poultry fat (37.8% FFA) in a 2 × 3 factorial arrangement. Addition of lipids increased (P < 0.001) final BW (19.9 vs. 18.4 kg) and ADG (460 vs. 405 g/d) regardless of source. Fat increased (P < 0.001) ADFI when added at 2.5% and then decreased ADFI with each further increment (663, 740, 681, and 653 g for 0%, 2.5%, 5.0%, and 7.5% fat, respectively). Inclusion of lipids linearly (P < 0.001) improved G:F (615, 615, 688, and 692 g/kg for 0%, 2.5%, 5.0%, and 7.5% fat, respectively) and ATTD of lipids (17.8%, 50.2%, 71.0%, and 77.3% for 0, 2.5, 5.0, and 7.5% fat, respectively) and GE (76.1%, 76.4%, 83.3%, and 84.4% for 0%, 2.5%, 5.0%, and 7.5% fat, respectively). Acidulated lipids resulted in similar performance compared with refined lipids and could be economical alternatives to more expensive lipid sources.

Background: Two studies were conducted to evaluate the effects of dietary natural betaine on sow reproductive performance during summer (Exp. 1) and non-summer months (Exp. 2). Treatments were designed as a 2 × 2 factorial arrangement with factors including dietary betaine (0 or 0.2%) and period of supplementation (lactation or post-weaning until 35 days post-insemination). In Exp. 1, 322 and 327 sows and in Exp. 2, 300 and 327 sows representing young (parity 1 and 2) and mature (parity 3 to 6) sows, respectively, were used. Results: In Exp. 1, supplementation of betaine during lactation increased sow body weight losses (− 11.95 vs. −14.63 kg; P = 0.024), reduced feed intake (4.12 vs. 4.28 kg/d; P = 0.052), and tended to reduce percentage of no-value pigs (P = 0.071). Betaine fed post-weaning reduced weaning-to-estrus interval (5.75 vs. 6.68 days; P = 0.054) and farrowing rate (86.74% vs. 91.36%; P = 0.060), regardless of parity group. Post-hoc analysis with sows clustered into 3 parity groups (1, 2 and 3, and 4+) indicated that betaine fed in lactation to parity 4+ sows (P = 0.026) and betaine fed post-weaning to parity 1 sows increased the number of pigs born in the subsequent cycle (P ≤ 0.05). In Exp. 2, betaine fed during lactation tended to reduce the weaning-to-estrus interval (6.64 vs. 7.50 days; P = 0.077) and farrowing rate (88.23% vs. 83.54%; P = 0.089), regardless of parity group. Feeding betaine post-weaning reduced number of pigs born (13.00 vs. 13.64; P = 0.04) and pigs born alive (12.30 vs. 12.82; P = 0.075), regardless of parity group. Conclusions: Using 0.2% betaine during the non-summer months did not benefit sow performance. During the summer, betaine supplementation in lactation increased subsequent litter size in parity 4+ sows. Betaine fed during the post-weaning period reduced the wean-to-estrus interval and farrowing rate, increased total number of pigs born for parity 1 sows and reduced total number of pigs born to parity 4+ sows. Further research is needed to determine if the detrimental effects on feed intake and farrowing rate may be correlated and depend on dietary betaine level.

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