Two experiments were conducted to evaluate the effects of live yeast supplementation on nursery pig performance, nutrient digestibility, and fecal microflora and to determine whether live yeast could replace antibiotics and growth-promoting concentrations of Zn and Cu in nursery pigs. In Exp. 1, 156 pigs were weaned at 17 d of age (BW = 5.9 kg) and allotted to a 2 × 2 factorial randomized complete block design (six or seven pigs per pen with six pens per treatment). Factors consisted of 1) dietary supplementation with oat products (oat flour and steam-rolled oats; 0 or 27.7%) and 2) yeast supplementation at 0 or 1.6 × 10⁷ cfu of Saccharomyces cerevisiae SC47/g of feed. In Exp. 2, 96 pigs were weaned at 17 d of age and allotted to a 2 × 2 factorial randomized complete block design (four pigs per pen with six pens per treatment) with factors of 1) diet type (positive control containing growth-promoting concentrations of Zn, Cu, and antibiotics or negative control) and 2) live yeast supplementation (0 or 2.4 × 10⁷ cfu of Saccharomyces cerevisiae SC47/g of feed). The inclusion of oat products in Exp. 1 decreased (P < 0.10) overall ADG and final BW. Yeast supplementation did not affect growth performance of pigs in Exp. 1 (P = 0.65); however, ADG in Exp. 2 was 10.6% greater (P < 0.01) and ADFI was increased by 9.4% (P < 0.10) in pigs supplemented with yeast in the positive control diet. Addition of Zn, Cu, and antibiotics to the diet improved gain:feed ratio during the prestarter period (P < 0.02) and overall (P = 0.10). In Exp. 1, inclusion of oat products increased (P < 0.01) total bacteria in feces when measured on d 10. Fecal lactobacilli measured on d 28 were reduced (P < 0.05) in pigs fed diets with oat products and yeast (interaction, P < 0.05). In Exp. 2, yeast supplementation decreased (P < 0.05) total bacteria and lactobacilli. Dietary yeast resulted in a greater (P < 0.05) yeast count in feces of pigs during the starter phase of Exp. 1. Yeast decreased (P < 0.10) the digestibility of DM, fat, and GE in the prestarter phase and DM, fat, P, and GE in the starter phase, whereas oat products increased the digestibility of DM, CP, fat, and GE (P < 0.05) in the prestarter phase. Results indicate that live yeast supplementation had a positive effect on nursery pig performance when diets contained growth-promoting antimicrobials. Nonetheless, the response was variable, and the conditions under which a response might be expected need to be further defined.

The objective of this study was to investigate the effect of increasing degrees of lipid peroxidation on structure and function of the small intestine of nursery pigs. A total of 216 pigs (mean body weight was 6·5 kg) were randomly allotted within weight blocks and sex and fed one of five experimental diets for 35 d (eleven pens per treatment with three to four pigs per pen). Treatments included a control diet without added lipid, and diets supplemented with 6 % soyabean oil that was exposed to heat (80°C) and constant oxygen flow (1 litre/min) for 0, 6, 9 and 12 d. Increasing lipid peroxidation linearly reduced feed intake (P<0·001) and weight gain (P=0·024). Apparent faecal digestibility of gross energy (P=0·001) and fat (P<0·001) decreased linearly as the degree of peroxidation increased. Absorption of mannitol (linear,P=0·097) andd-xylose (linear,P=0·089), measured in serum 2 h post gavage with a solution containing 0·2 g/ml ofd-xylose and 0·3 g/ml of mannitol, tended to decrease progressively as the peroxidation level increased. Increasing peroxidation also resulted in increased villi height (linear,P<0·001) and crypt depth (quadratic,P=0·005) in the jejunum. Increasing peroxidation increased malondialdehyde concentrations (quadratic,P=0·035) and reduced the total antioxidant capacity (linear,P=0·044) in the jejunal mucosa. In conclusion, lipid peroxidation progressively diminished animal performance and modified the function and morphology of the small intestine of nursery pigs. Detrimental effects were related with the disruption of redox environment of the intestinal mucosa.

Two experiments were conducted to evaluate the effect of lysolecithin on performance and nutrient digestibility of nursery pigs and to determine the effects of fat encapsulation by spray drying in diets fed in either meal or pelleted form. In Exp. 1, 108 pigs (21 d of age; 5.96 ± 0.16 kg BW) were allotted to one of four dietary treatments (as-fed basis): 1) control with no added lard, 2) control with 5% added lard, 3) treatment 2 with 0.02% lysolecithin, and 4) treatment 2 with 0.1% lysolecithin in a 35-d experiment. Added lard decreased ADG (P = 0.02) and ADFI (P < 0.06) during d 15 to 35 and overall. Lysolecithin improved ADG linearly (P = 0.04) during d 15 to 35 and overall, but did not affect ADFI or G:F. Addition of lard decreased the digestibility of DM (P = 0.10) and CP (P = 0.05) and increased (P = 0.001) fat digestibility when measured on d 10. Lysolecithin at 0.02%, but not 0.10%, tended to improve the digestibility of fat (P = 0.10). On d 28, digestibilities of DM, fat, CP, P, (P = 0.001), and GE (P = 0.03) were increased with the addition of lard, and lysolecithin supplementation linearly decreased digestibilities of DM (P = 0.003), GE (P = 0.007), CP, and P (P = 0.001). In Exp. 2, 144 pigs (21 d of age, 6.04 ± 0.16 kg BW) were allotted to one of six treatments in a 3 × 2 factorial randomized complete block design. Factors included 1) level (as-fed basis) and source of fat (control diet with 1% lard; control diet with 5% additional lard; and control diet with 5% additional lard from encapsulated, spray-dried fat) and 2) diet form (pelleted or meal). Addition of lard decreased feed intake during d 0 to 14 (P = 0.04), d 15 to 35 (P = 0.01), and overall (P = 0.008), and improved G:F for d 15 to 35 (P = 0.04) and overall (P = 0.07). Encapsulated, spray-dried lard increased ADG (P = 0.004) and G:F (P = 0.003) during d 15 to 28 compared with the equivalent amount of fat as unprocessed lard. Pelleting increased ADG (P = 0.006) during d 0 to 14, decreased feed intake during d 15 to 35 (P = 0.01), and overall (P = 0.07), and increased G:F during all periods (P < 0.02). Fat digestibility was increased (P = 0.001) with supplementation of lard, and this effect was greater when diets were fed in meal form (interaction, P = 0.004). Pelleting increased the digestibility of DM, OM, and fat (P < 0.002). Results indicate that growth performance may be improved by lysolecithin supplementation to diets with added lard and by encapsulation of lard through spray drying. Copyright © 2004. . Copyright 2004 Journal of Animal Science

Dietary lipid supplementation benefits the prolific and high-producing modern lactating sow. A comprehensive review of recent studies showed that lipid supplementation increases average daily energy intake, which is partitioned for lactation as indicated by greater milk fat output and improved litter growth rate. Recent compelling findings showed that addition of particular lipids during lactation improved the subsequent reproductive outcome of sows. Such benefits were related to the level of dietary essential fatty acids (EFA, linoleic acid, C18:2n-6; and α-linolenic acid, C18:3n-3) during lactation. Lactation diets without supplemental EFA resulted in a pronounced negative balance (intake minus milk output) of linoleic (−25.49 g/d) and α-linolenic acid (−2.75 g/d); which compromised sow fertility (farrowing rate < 75 % and culling rates > 25 % of weaned sows). This phenomenon seems to be increasingly important with advancing sow age because of a progressive reduction of body EFA pool over successive lactations. The net effect of supplemental EFA during lactation was to create a positive EFA balance, which improved the subsequent reproduction of sows. Adequate linoleic acid intake improved the proportion of sows that farrowed in the subsequent cycle (Farrowing rate (%) = [(−1.5 × 10−3 × linoleic acid intake (g/d)2) + (0.53 × linoleic acid intake (g/d)) + (45.2)]; quadratic P = 0.002, R2 = 0.997, RMSE = 0.031). In addition, increasing linoleic acid intake increased the number of pigs born in the subsequent cycle (total pigs born (n) = [(9.4 × 10−5 × linoleic acid intake (g/d)2) + (0.04 × linoleic acid intake (g/d)) + (10.94)]; quadratic P = 0.002, R2 = 0.997, RMSE = 0.031). Supplemental α-linolenic acid resulted in a rapid return to estrus (sows bred: sows weaned = 94.2 %; wean-to-estrus interval = 4.0 d) and achieved a high retention of pregnancy (sows pregnant: sows bred = 98 %). Collectively, we conclude that a minimum dietary intake of 10 g/d of α-linolenic acid, simultaneous with a minimum of 125 g/d of linoleic acid should be provided to ≥ 95 % of the sows; thereby, achieving a maximum sow reproductive efficiency through multiple mechanisms that include rapid return to estrus, high maintenance of pregnancy and large subsequent litter size in mature sows, that appear to be susceptible to EFA deficiency.

This study was designed to evaluate the effects of vitamin E supplementation on pork quality of two genotypes with distinct differences in pork quality traits. Pigs (n = 240; BW = 87 ± 0.35 kg) were allotted by weight to one of 20 treatments (4 pens/treatment, 3 pigs/pen) in a 2 × 2 × 5 factorial randomized complete block design. Factors included 1) genotype (Berkshire or Hampshire sired), 2) sex (gilts or barrows), and 3) vitamin E level (12.1, 54.7, 98.8, 174.0, and 350.6 IU of vitamin E/kg diet). Hampshire-sired pigs had greater average daily gain (1.05 vs 0.98 kg) and gain:feed (0.30 vs 0.27) and less average daily feed intake (ADFI) (3.46 vs 3.62 kg) than Berkshire-sired pigs (P < 0.001) for the 6-wk study. Hampshire-sired barrows consumed more feed (3.54 vs 3.38 kg/d) and were less efficient (0.29 vs 0.31) than Hampshire-sired gilts (P < 0.05), but this sex difference was not observed in Berkshire-sired pigs (interaction, P < 0.05). Berkshire-sired pigs had greater backfat (34.1 vs 21.1 mm; P < 0.001), reduced longissimus muscle area (37.6 vs 46.3 cm²; P < 0.001), reduced lean percentage (53.0 vs 55.8; P < 0.001), and a greater head-on yield (79.8 vs 79.2; P < 0.05). Vitamin E increased (P < 0.05) ADFI linearly (P < 0.05), but had no effects on carcass composition. Loin chops from Hampshire-sired pigs had reduced ultimate pH (5.64 vs 5.91), greater drip loss (92.2 vs 66.3 mg), and increased Minolta L* (52.6 vs 48.6), a* (8.9 vs 7.5), and b* (6.9 vs 5.2) values compared to Berkshire-sired pigs (P < 0.001). Vitamin E had no effect on pH, temperature, drip loss, and L* or a* values, but tended (P < 0.07) to increase b* values linearly (P < 0.06). Oxidation as indicated by thiobarbituric acid reactive substances (TBARS) was greatest in Hampshire-sired gilts at the lowest level of vitamin E, and decreased linearly (P < 0.001) with additional vitamin E. However, TBARS responded in a cubic fashion (P < 0.05) to vitamin E in Hampshire-sired barrows and were not affected in Berkshire-sired gilts or barrows (three-way interaction, P < 0.02). Hampshire-sired pigs had greater TBARS than Berkshire-sired pigs (0.053 vs 0.047 mg malondialdehyde equivalents/kg). Vitamin E supplementation increased serum concentrations of vitamin E on d 21 (1.06 to 4.79 μg/mL) and d 42 (1.02 to 2.82 μg/mL) and increased tissue concentrations of vitamin E (1.99 to 4.83 μg/g) linearly (P < 0.001). Vitamin E supplementation was not effective in improving fresh meat quality in genotypes with poor or superior meat quality traits.

Background: This study evaluated the use of dietary vitamin E and polyphenols on growth, immune and oxidative status of weaned pigs fed peroxidized lipids. A total of 192 piglets (21 days of age and body weight of 6.62 ± 1.04 kg) were assigned within sex and weight blocks to a 2 × 3 factorial arrangement using 48 pens with 4 pigs per pen. Dietary treatments consisted of lipid peroxidation (6% edible soybean oil or 6% peroxidized soybean oil), and antioxidant supplementation (control diet containing 33 IU/kg DL-α-tocopheryl-acetate; control with 200 IU/kg additional dl-α-tocopheryl-acetate; or control with 400 mg/kg polyphenols). Pigs were fed in 2 phases for 14 and 21 days, respectively. Results: Peroxidation of oil for 12 days at 80 °C with exposure to 50 L/min of air substantially increased peroxide values, anisidine value, hexanal, and 2,4-decadienal concentrations. Feeding peroxidized lipids decreased (P < 0.001) body weight (23.16 vs. 18.74 kg), daily gain (473 vs. 346 g/d), daily feed intake (658 vs. 535 g/d) and gain:feed ratio (719 vs. 647 g/kg). Lipid peroxidation decreased serum vitamin E (P < 0.001) and this decrease was larger on day 35 (1.82 vs. 0.81 mg/kg) than day 14 (1.95 vs. 1.38 mg/kg). Supplemental vitamin E, but not polyphenols, increased (P ≤ 0.002) serum vitamin E by 84% and 22% for control and peroxidized diets, respectively (interaction, P = 0.001). Serum malondialdehyde decreased (P < 0.001) with peroxidation on day 14, but not day 35 and protein carbonyl increased (P < 0.001) with peroxidation on day 35, but not day 14. Serum 8-hydroxydeoxyguanosine was not affected (P > 0.05). Total antioxidant capacity decreased with peroxidation (P < 0.001) and increased with vitamin E (P = 0.065) and polyphenols (P = 0.046) for the control oil diet only. Serum cytokine concentrations increased with feeding peroxidized lipids on day 35, but were not affected by antioxidant supplementation (P > 0.05). Conclusion: Feeding peroxidized lipids negatively impacted growth performance and antioxidant capacity of nursery pigs. Supplementation of vitamin E and polyphenols improved total antioxidant capacity, especially in pigs fed control diets, but did not restore growth performance.