Dose-Dependent Effects of Supplementing a Two-Strain Bacillus subtilis Probiotic on Growth Performance, Blood Parameters, Fecal Metabolites, and Microbiome in Nursery Pigs

This experiment was conducted to evaluate the effects of dietary supplementation level of a two-strain Bacillus subtilis probiotic on growth performance, blood parameters, fecal metabolites, and microbiome in nursery pigs. A total of 54 weaned piglets were allotted to three treatments in three replicate pens with six pigs/pen for a 28 d feeding trial. The treatments were as follows: control: no probiotic supplementation; Pro1x: B. subtilis supplementation at 1.875 × 105 CFU/g diet; and Pro10x: B. subtilis supplementation at 1.875 × 106 CFU/g diet. Body weight at d 14 postweaning (p = 0.06) and average daily gain for d 0 to 14 postweaning (p < 0.05) were greater in the Pro1x treatment than in the other treatments. Blood glucose levels were greater in both probiotic treatments than in the control treatment at d 14 postweaning (p < 0.05). In the fecal short-chain fatty acid (SCFA) concentrations, the butyrate concentrations were greater in the Pro1x treatment than in the other treatments (p < 0.05), and the acetate, propionate, and total SCFA concentrations were greater in the Pro1x treatment than in the Pro10x treatment (p < 0.05). The beta diversity of fecal microbiome composition at d 14 postweaning based on Unweighted Unifrac analysis was dissimilar between the Pro1x and Pro10x treatments (p < 0.05). In conclusion, dietary B. subtilis supplementation of two strains selected to reduce effects of pathogenic Escherichia coli to nursery diets at 1.875 × 105 CFU/g diet improved the growth rate in the early postweaning period, increased fecal SCFA concentrations and altered the fecal microbial community composition. A higher dose of B. subtilis did not improve the performance parameters over those of the control piglets.

Effects of multiple vitamin E levels and two fat sources in diets for swine fed to heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations, immune capacity, and antioxidant capacity of plasma and tissue

The study objective was to evaluate the effect of two fat sources and graded levels of vitamin E (VE) supplementation on tissue fatty acid profile, VE concentrations, immune capacity, and antioxidant capacity of plasma and tissues of pigs at heavy slaughter weight (150 kg). A total of 48 individually-fed pigs (24 barrows, 24 gilts; 28.44 ± 2.69 kg) were randomly assigned to eight dietary treatments in a 2 × 4 factorial arrangement. The two fat treatments were either 5% tallow (TW) or 5% distiller's corn-oil (DCO). The VE treatments included four levels of α-tocopheryl-acetate (11, 40, 100, and 200 ppm). Compared to pigs fed the DCO diet, pigs fed the TW diet had greater SFA (C14, C16, and C18; P < 0.05) and MUFAs (C14:1, C16:1, C18:1, and C20:1; P < 0.05), lower PUFA (C18:2n-6, C18:3n-3, C20:2, C20:3, and C20:4; P < 0.05) and iodine value in the backfat and belly fat. Increasing dietary VE supplementation level increased α- and total tocopherol concentrations in plasma (linear and quadratic, P < 0.05), liver, and loin muscle (linear, P < 0.06), superoxide dismutase activity (quadratic, P < 0.05), but decreased γ-tocopherol concentrations in liver (linear, P = 0.06), plasma, and loin muscle (quadratic, P < 0.07), and decreased liver glutathione disulfide (GSSG; linear, P = 0.07) and malondialdehyde (MDA) content (quadratic, P < 0.05). There was an interaction between fat sources and dietary VE supplementation level on the concentration of α-tocopherol in the loin muscle (P < 0.05) wherein a greater increase was observed in the TW treatment than the DCO treatment with the increasing dietary VE supplementation level. In conclusion, dietary FA composition in TW and DCO affected the composition of most FA in backfat, belly fat, and liver while increasing VE supplementation level did not significantly alter the FA profile in these tissues. Increasing dietary VE supplementation level increased tocopherol concentrations in plasma, liver and loin muscle, and improved antioxidant capacity while tocopherol concentrations in plasma, liver and loin muscle in the TW treatment increased more than they did in the DCO treatment.

Effects of multiple vitamin E levels and two fat sources in diets for swine fed to heavy slaughter weight of 150 kg: I. Growth performance, lean growth, organ size, carcass characteristics, primal cuts, and pork quality

The study objective was to evaluate the effect of two fat source and graded levels of vitamin E (VE) supplementation on growth performance, carcass characteristics, and meat quality of pigs at heavy slaughter weight (150 kg). A total of 48 individually-fed pigs (24 barrows, 24 gilts; 28.44  ± 2.69 kg) were blocked by sex and weight and randomly assigned to eight dietary treatments in a 2 × 4 factorial arrangement. Fat treatments were 5% tallow (TW) and distiller's corn-oil (DCO) in the diets. The VE treatments included four levels of α-tocopheryl-acetate (11, 40, 100, and 200 ppm). Growth performance, carcass traits, organ weight, primal cuts, and pork quality were measured. Increasing dietary VE supplementation levels linearly increased overall Average daily gain (ADG) and average daily feed intake (P < 0.05), with an interaction between fat sources and VE supplementation levels on cumulative ADG (P < 0.05) during phases 1 and 3 (28 to 100 kg) and 1 to 4 (28 to125 kg) wherein ADG in the pigs fed the DCO diet, but not the TW diet, increased with increasing dietary VE supplementation level. A similar interaction was observed in 24 h pH and picnic shoulder (P < 0.05). No notable effect of fat source was observed in growth performance. With increasing dietary VE supplementation levels, there were quadratic responses in pork pH at 45 min and 24 h postmortem with the highest value in 40 and 100 ppm of VE levels while TBARS values on day 7 postmortem decreased linearly (P < 0.05). Compared with the TW diet, the DCO diet resulted in greater TBARS values during 7 postmortem (P < 0.05; day 5, P = 0.09). These results demonstrated that increasing dietary VE supplementation level could enhance growth rate and feed intake and reduce lipid peroxidation of pork whereas the diet containing DCO as a fat source could negatively affect pork shelf-life and carcass characteristics and that increasing VE supplementation level had no notable interaction with fat sources for carcass characteristics.

Effect of Additional Iron Injection to Suckling Pigs on Hematocrit Level during the Suckling Period

Two experiments were conducted to evaluate the effects of additional iron injection to suckling piglets on hematocrit level during the suckling period. In Experiment 1, a total of 24 piglets were allotted into 3 treatments within litter based on body weight and sex at d 1 of age. Treatments were: (1) Control: a 200 mg iron-dextran intramuscular injection only at d 0 of experiment (d 1 of age), (2) Iron100: intramuscular iron-dextran injections at d 0 (200 mg iron) and 15 (11 d before weaning) of experiment (100 mg iron), and (3) Iron200: intramuscular iron-dextran injections at d 0 (200 mg iron) and 15 of experiment (200 mg iron). In Experiment 2, a total of 20 piglets were allotted into 2 treatments within litter based on body weight and sex at d 1 to 2 of age. Treatments were: (1) Iron100b: 100 mg iron-dextran intramuscular injection at d 0 of experiment (d 1 to 2 of age), and (2) Iron200b: 200 mg iron-dextran intramuscular injection at d 0 of experiment. An additional 200 mg iron-dextran was injected to all piglets intramuscularly at d 14 of experiment (11 d before weaning). In Experiment 1, there was no difference in hematocrit levels among treatments at d 15 of experiment. Both iron treatments had greater hematocrit levels than the Control treatment at d 22 and 26 of experiment (p < 0.05). The Iron200 treatment had greater hematocrit level at d 26 of experiment (p < 0.05) and tended to have a greater increase of hematocrit levels in d 22 to 26 of experiment (p = 0.09) than the Iron100 treatment. In Experiment 2, the Iron200b treatment had greater hematocrit levels than the Iron100b treatment in d 14 and 25 (p < 0.05) of experiment. Hematocrit level changes tended to be greater in the Iron200b treatment in d 0 to 14 (p = 0.08) of experiment but lower in d 14 to 25 (p < 0.05) of experiment than the Iron100b treatment. The additional iron injection to suckling piglets increased hematocrit levels with greater values at weaning in the higher injection level whereas the increase was greater when the hematocrit level was low at the time of additional injection.

Effects of dietary vitamin E and fat supplementation in growing-finishing swine fed to a heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations and antioxidant capacity of plasma and tissue

The study aimed to assess the effects of vitamin E (VE) supplementation and fat source on fatty acid (FA) composition, VE concentrations, and antioxidant capacity in plasma and tissues of pigs fed to a heavy slaughter weight (150 kg). A total of 64 pigs (32 barrows, 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement. Fat sources included corn starch (CS), 5% tallow (TW), 5% distiller’s corn oil (DCO), and 5% coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Five-phase diets were formulated to meet requirement estimates of NRC (2012) and fed to pigs for each period of 25 kg from 25 to 150 kg. Increasing VE supplementation level increased C16:1 (P < 0.05) content but decreased C20:0 (P < 0.05) content in backfat and belly fat, while in liver, it increased C17:0 (P < 0.05) but decreased C18:0 (P < 0.05). Compared to the pigs fed the CS diet, the pigs fed the CN diet had greater (P < 0.05) content of total saturated FA, the pigs fed the DCO diet had greater (P < 0.05) content of total polyunsaturated FA content and iodine value, and the pigs fed the TW diet had greater (P < 0.05) content of total monounsaturated FA in backfat, belly fat, and liver. Plasma VE concentrations increased linearly (P < 0.05) with increasing length of feeding but faster (P < 0.05) in the pigs fed the CN and TW diets compared with the CS and DCO diets within the 200 ppm VE level; the pigs fed the DCO diet had the highest plasma VE concentrations (P < 0.05) from Phase 2 to Phase 5 within the 11 ppm VE level. The VE concentrations in liver and loin muscle (P < 0.05) increased with increasing dietary VE level from 11 to 200 ppm, but it was not affected by dietary fat source. There was no effect of VE supplementation and fat source on antioxidant capacity in plasma and liver except that pigs fed the DCO diet had greater liver SOD activity (P < 0.05) than the pigs fed the CN diet. In conclusion, dietary VE supplementation did not affect FA profile in backfat, belly fat, and liver consistently, while dietary FA composition with different fat sources affected much of the FA profile in backfat, belly fat, and liver. The higher level of VE supplementation increased liver and muscle VE concentrations and dietary fat sources affected plasma VE concentrations differently (P < 0.05), wherein the TW and CN diets increased the VE absorption greater than the DCO diet.

PSIII-16 The Effects of Secondary Iron Injection to Suckling Piglets Injected with Two Levels of Iron at Birth on Growth Performance and Hematocrit Level in Suckling Period

This experiment was conducted to evaluate the effects of secondary iron injection in suckling piglets injected with 2 levels of iron at birth on growth performance and hematocrit level during the suckling period. Twenty suckling pigs from 5 litters were allotted into 2 treatments within litter (10 pigs per treatment) based on body weight and gender as follows: 1) Iron100b: intramuscular injection of 100 mg iron-dextran at birth (d 1-2 of age), and 2) Iron200b: intramuscular injection of 200 mg iron-dextran at birth. A 200 mg iron-dextran was injected to all piglets intramuscularly at d 14 after the first injection (d 15-16 of age; 11 d before weaning at d 26-27 of age). Body weight and hematocrit level were measured at d 0, 7, 14 (before second injection), 21, and 25 (weaning) after the first injection. No difference was observed in growth performance between the treatments. The Iron200b treatment had greater hematocrit levels than the Iron100b treatment at d 14 (P &lt; 0.05; 32.50 vs. 37.40% for Iron100b and Iron200b, respectively), 21 (P = 0.06), and 25 (P &lt; 0.05; 37.90 vs. 40.75%) after the first injection (d 0, 7, and 11 after second injection, respectively). The changes in hematocrit levels tended to be greater for the Iron200b treatment than the Iron100b treatment in d 7-14 (P = 0.08) and 0-14 (P = 0.06; 5.55 vs. 11.95%) after the first injection. After the second injection, the Iron100b treatment had greater increases (P &lt; 0.05) in hematocrit levels than the Iron200b treatment for d 14-21 and 14-25 (5.40 vs. 3.35%) of the experiment. In conclusion, with the second injection, the 200 mg iron injection at birth had greater hematocrit levels than the 100 mg iron injection until weaning whereas the increase in hematocrit level by the second injection was greater in the 100 mg iron injection at birth than the 200 mg iron.

PSII-15 Effect of Secondary Iron Injection to Suckling Pigs on Growth Performance and Hematocrit Level in Suckling Period

The objective of this study was to evaluate the effects of secondary iron injection in suckling pigs on growth performance and hematocrit level in the suckling period. At d 1 of age, a total of 24 suckling pigs from 4 litters were allotted into 3 treatments within litter (8 pigs per treatment) based on body weight and gender as follows: 1) Control: no additional iron injection, 2) Iron100: secondary intramuscular injection of 100 mg iron-dextran, and 3) Iron200: secondary intramuscular injection of 200 mg iron-dextran. The initial 200 mg iron-dextran was injected intramuscularly on d 1 of age with a second injection given to the pigs on 11 d before weaning (d 16 of age). All piglets were weaned at d 27 of age. Body weight and hematocrit level were measured at d 0, 7, and 11 (weaning) post-injection. There was no significant difference in growth performance among the treatments. The Iron100 and Iron200 treatments had greater hematocrit levels than the Control treatment at d 7 and 11 post-injection (P &lt; 0.05) with a greater hematocrit level in the Iron200 treatment than the Iron100 treatment at d 11 post-injection (P &lt; 0.05; 34.25, 38.75, and 41.19% for Control, Iron100 and Iron200, respectively). For changes in hematocrit level, the Iron100 and Iron200 treatments had greater increases than the Control treatment in d 0-7 and d 0-11 post-injection (P &lt; 0.05; -1.31, 4.31, and 5.75%) with no difference between the Iron100 and Iron200 treatments. In d 7-11 post-injection, the Iron200 treatment had a greater increase in hematocrit level than the Iron100 treatment with an intermediate value in the Control treatment (P &lt; 0.05; 0.44, -0.06 and 1.38%). In conclusion, the secondary iron injection to suckling piglets did not affect growth performance until weaning whereas the injections increased hematocrit levels resulting in a greater value at weaning in the higher level of second iron injection.

Effects of dietary vitamin E and fat supplementation in growing-finishing swine fed to a heavy slaughter weight of 150 kg: I. Growth performance, lean growth, organ size, carcass characteristics, primal cuts, and pork quality

The study aimed to assess the effect of vitamin E (VE) supplementation and fat source on growth performance, lean growth, organ size, carcass characteristics, and pork quality of pigs at a heavy slaughter weight of 150 kg. A total of 64 pigs (32 barrows and 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and body weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement with main effects of fat source (corn starch [CS; no fat added], 5% tallow [TW], 5% distiller's corn oil [DCO], and 5% coconut oil [CN]) and VE supplementation level (11 and 200 ppm). Five-phase diets were formulated to meet requirement estimates of NRC and fed to pigs with each period of 25 kg from 25 to 150 kg. Increasing dietary VE supplementation from 11 to 200 ppm tended to increase average daily gain (ADG) in phase 5 (P = 0.08), and gain to feed ratio (G/F) in phase 4 (P = 0.06) and phase 5 (P = 0.06) resulting in increased G/F in the overall period 
(P = 0.10). Compared with the pigs fed the CS diet in the overall period, the pigs fed DCO diets had greater ADG (P < 0.05), the pigs fed the TW and CN diets had lower average daily feed intake (P < 0.05), and the pigs fed the fat-added diets had greater G/F (P < 0.05). Belly firmness was greatest in the pigs fed the CN diet and lowest in those fed the DCO diet (P < 0.05). Increasing dietary VE level from 11 to 200 ppm increased absolute and relative liver weight, absolute ham yield (P < 0.05), and tended to increase the relative yield of picnic shoulder (P = 0.07) and ham (P = 0.06) and the pigs fed the corn oil diet tended to have greater belly yield (P = 0.08) than the other fat treatments. Increasing dietary VE level increased 45-min pH and ΔpH at slaughter but decreased a* value, chroma (P < 0.10), and belly depth (P < 0.05). However, no effects of VE supplementation and fat source were observed on the other carcass traits and meat quality measurements. In conclusion, increasing dietary 
VE level from 11 to 200 ppm slightly increased growth rate and feed efficiency in the late finishing periods, and the addition of fat increased feed efficiency and backfat thickness, decreased lean content, and altered belly firmness. While there were some effects of VE supplementation and fat source observed on organ weight, primal cuts, carcass traits, and meat quality, there was no strong evidence that VE supplementation and fat source materially affected these measurements except for belly firmness.

Assessment of visceral organ growth in pigs from birth through 150 kg

Visceral organs (VO) are essential for their role in the metabolism and distribution of consumed nutrients as well as other life functions in animals. Two experiments were conducted to assess the natural longitudinal changes that the VO undergo from birth through 150 kg body weight (BW). In Experiment 1, a total of 96 crossbred pigs were euthanized at birth (pre-suckle), d 1, 2, 3, 5, 7, 14, 21 (weaning), 22, 23, 24, 26, 28, 42, 49, and 63 of age. In Experiment 2, a total of 48 crossbred pigs were euthanized at 30, 50, 75, 100, 125, and 150 kg of BW. The absolute weight of VO, and the volume and length of the gastrointestinal tract (GIT) were measured. In both experiments, the absolute weight of VO, GIT length, and their volume increased (linear, quadratic, and/or cubic, P < 0.05) as BW and age increased. In Experiment 1, the relative weight of VO (liver, kidney, heart, and lung) decreased after initially increasing within the first week of life (linear, quadratic, and/or cubic, P < 0.05), whereas the relative weight of all VO decreased as BW increased in Experiment 2 (linear and/or quadratic, P < 0.05). The relative length of small intestine decreased and that of large intestine increased as age increased in Experiment 1 (linear and quadratic, P < 0.05), whereas the relative length of the small and large intestine in Experiment 2 were relatively constant at 80% and 20% of the total length of the intestine, respectively. As age and BW increased, the relative volume of the large intestine to the total volume of the GIT increased (linear and/or quadratic, P < 0.05), while the relative volume of the small intestine decreased (linear and/or quadratic, P < 0.05). In conclusion, results showed that both absolute and relative measurements (weight, volume, and length) of VO were dependent on the BW (age) of the pig.

Amino acid digestibility in diets containing copra meal with β-mannanase fed to growing pigs

OBJECTIVE

The objective of this study was to estimate standardized ileal digestibility (SID) of amino acids (AA) in growing pigs fed diets containing increasing levels of copra meal (CM) with β-mannanase supplementation.

METHODS

Twenty barrows (initial body weight: 34.43±0.11 kg) surgically fitted with T-cannulas at the distal ileum were individually housed in metabolism crates. Pigs were allotted to 5 dietary treatments in a completely randomized design with 4 replicates per treatment. The dietary treatments were: i) NC, negative control, corn-soybean meal (SBM) based diet, ii) PC, positive control, basal diet + 0.10% β-mannanase supplementation (800 IU/kg), iii) CM6, PC diet with 6% CM supplementation, iv) CM12, PC diet with 12% CM supplementation, and v) CM18, PC diet with 18% CM supplementation. A nitrogen-free diet was used to estimate basal endogenous losses of AA for SID calculation. All experimental diets contained 0.5% chromic oxide as an indigestible marker. Each period consisted of a 4-d diet adaptation period and a 3-d ileal digesta collection period.

RESULTS

There were no differences in apparent ileal digestibility (AID) and SID of all AA between the NC and PC treatments except that the PC treatment had lower AID and SID of glycine than the NC treatment (p<0.05). There were linear decreases in AID and SID of lysine (p<0.05) and aspartic acid (p = 0.06; tendency) with increasing levels of CM in the diets with β-mannanase.

CONCLUSION

The β-mannanase supplementation had no effect on AA digestibility in pigs fed the corn-SBM based diet but increasing levels of CM reduced SID of lysine and aspartic acid.

PSI-14 The effect of creep feed and its nutrient level on growth performance in suckling and weaning pigs

Two experiments were conducted to evaluate the effect of creep feed (CF) and its nutrient level on growth performance of suckling and weaning pigs. In Exp. 1, eight litters (d 20 of age) were allotted to 2 treatments based on breed, litter size and weight as follows: no-CF (n=3) and CF (n=5; offered from 8 days before weaning). At weaning (d 28 of age), the pigs were divided into 3 treatments (6 pigs/pen, 3 replicates; initial BW: 9.66±0.34 kg) balanced with gender, weight, and breed as follows: eaters, noneaters, and no-CF. In Exp. 2, seven litters (d 12 of age) were allotted to 2 treatments as follows: HN (n=4): CF with fish meal (3%), blood meal (2.4%), and whey (15%), and LN (n=3): CF without those ingredients. At weaning (d 25 of age), eater pigs were divided into 2 treatments (6 pigs/pen, 3 replicates; initial BW: 7.53±0.97 kg) as follows: HN-eaters and LN-eaters. In both experiments, the pigs were fed a common nursery diet for 21 days. The CF was mixed with 1% Cr2O3 to measure fecal color for eater/noneater categorization. Piglet weaning weight was not different among eaters and non-eaters in both experiments (in Exp. 1, P=0.99; 9.35, 9.33, and 9.20 kg for eaters, noneaters, and no-CF, respectively). There was no difference on overall nursery growth performance in both experiments. The HN-eaters tended to have greater ADG (P=0.08; 0.506 vs. 0.427 g/d for HN-eaters and LN-eaters, respectively) and G:F (P=0.09; 0.889 vs. 0.717, respectively) than LN-eaters in d 7-14 postweaning in Exp. 2. The CF intake and percentage of eaters/litter (P=0.60; 85.6 and 80.87% for LN and HN, respectively) in Exp. 2 were not different between treatments. In conclusion, CF did not affect overall piglet growth in suckling and nursery phases, but nutrient level might affect early nursery pig growth.

PSI-13 The effect of Advanced Digestive Enhancing Protein Plus Technology on growth performance and fecal score in weaning pigs

The experiment was conducted to evaluate the effect of ADEPPTTM on growth performance and fecal score in weaning pigs. At weaning, a total of 54 pigs, 7.47 ± 0.79 kg of initial body weight (BW), were assigned to 3 treatments in 3 replicates with 6 pigs per pen based on sex, breed, and BW for a 28-d feeding trial. The pigs were fed corn-soybean meal-based diets containing 0.0, 0.5, and 1.0% of ADEPPTTM (Proprietary product of Vets Plus, Inc., Menomonie, WI) in 2 phases (d 0-14 and d 15-28 postweaning, respectively). In the first week (d 3-5 postweaning) of the trial, a diarrhea pig was removed from each pen when diarrhea was observed, housed in the separate pens within treatment (n=3 pigs per treatment) and then treated with a 100-ml solution of electrolytes and ADEPPTTM by drenching for 3 days. Growth performance and fecal score (1=normal to 4=watery diarrhea) were measured. All data were analyzed by ANOVA using GLM procedure of SAS for linear and quadratic effects of increasing ADEPPTTM levels. There were no significant differences in BW, ADG, and ADFI throughout the entire period whereas a quadratic trend was observed in G:F for overall period with increasing ADEPPTTM levels (P&lt; 0.10; 0.583, 0.621, and 0.586 for 0.0, 0.5, and 1.0% of ADEPPTTM levels, respectively) with the greatest value in the 0.5% ADEPPTTM treatment. Fecal score tended to decrease linearly with increasing ADEPPTTM levels during d 0-7 postweaning (P=0.11; 1.88, 1.81, and 1.57, respectively). There was no significant difference on fecal score of diarrhea pigs while ADG tended to increase linearly in d 21-28 postweaning (P=0.08; 533.6, 700.2, and 853.9 g/d, respectively) with increasing ADEPPTTM levels. This result indicated that ADEPPTTM could have a potential to enhance growth performance of weaning pigs at 0.5% level and might be effective on postweaning diarrhea pigs.

Effects of Dietary β-Mannanase Supplementation on Growth Performance, Apparent Total Tract Digestibility, Intestinal Integrity, and Immune Responses in Weaning Pigs

The experiment aimed to investigate the effects of dietary β-mannanase supplementation on growth performance, apparent total tract digestibility (ATTD) of nutrients, intestinal integrity, and the immunological and oxidative stress parameters in weaning pigs. A total of 64 newly weaning pigs (initial body weight: 6.96 ± 0.70 kg) were allotted to two dietary treatments in eight replicates per treatment with four pigs per pen based on body weight and sex. Dietary treatments were 1.) CON (control: corn-soybean meal based basal diet) and 2.) β-mannanase (basal diet +0.06% β-mannanase). The β-mannanase supplementation did not affect growth performance, concentrations of acute phase protein, superoxide dismutase and glutathione peroxidase. However, the pigs fed the β-mannanase-supplemented diet had greater ATTD of ether extract, jejunum villus height, and villus height-to-crypt depth ratio, and lower crypt depth compared with those fed the CON diet (p < 0.05). The pigs fed the β-mannanase-supplemented diet tended to have the lower count of E. coli in cecum than those fed the CON diet (p = 0.08). In conclusion, dietary β-mannanase supplementation did not affect growth performance, immune response and oxidative stress of weaning pigs, whereas it increased fat digestibility and had positive effects on intestinal integrity and cecum microflora by reducing the count of E.coli.

Distribution of injected fat-soluble vitamins in plasma and tissues of nursery pigs

Objective

The objective of this experiment was to investigate the effects of fat-soluble vitamin injection on plasma and tissue vitamin status in nursery pigs.

Methods

A total of 16 pigs (initial body weight: 7.15±1.1 kg) were allotted to 2 treatments at d 7 post-weaning. Pigs were fed a corn-soybean meal-based basal diet with no supplemental vitamin A and i.m. injected with 300,000 IU of retinyl palmitate, 900 IU of d-α-tocopherol and 30,000 IU of vitamin D₃ with control pigs having no vitamin injection. Blood (d 0, 3, 7, and 14 post-injection) and tissue samples (liver, brain, heart, lung, and muscle; d 7 and 14 post-injection) were collected from pigs. Retinyl palmitate, retinol, and α-tocopherol concentrations were analyzed in plasma and tissues, while plasma was assayed for 25-hydroxycholecalciferol (25-OHD₃).

Results

Plasma retinol and 25-OHD₃ concentrations increased by the vitamin injection from d 3 to 14 post-injection (p<0.05) whereas plasma retinyl palmitate was detected only in the vitamin treatment at d 3 and 7 post-injection (115.51 and 4.97 μg/mL, respectively). Liver retinol, retinyl palmitate, and retinol+retinyl palmitate concentrations increased by retinyl palmitate injection at d 7 and 14 post-injection (p<0.05) whereas those were not detected in the other tissues. The d-α-tocopherol injection increased α-tocopherol concentrations in plasma at d 3 and 7 post-injection (p<0.05) and in liver, heart (p<0.10), and muscle (p<0.05) at d 7 post-injection.

Conclusion

Fat-soluble vitamin injection increased plasma status of α-tocopherol, retinol, retinyl palmitate and 25-OHD₃. As plasma levels decreased post-injection, vitamin A level in liver and vitamin E level in muscle, heart and liver increased. The α-tocopherol found in plasma after injection was distributed to various tissues but retinyl palmitate only to the liver.

PSI-5 Effects of fat-soluble vitamin injection on plasma and tissue vitamin concentrations in nursery pigs

An experiment was conducted to investigate distribution of injected fat-soluble vitamins in plasma and tissue of nursery pigs. A total of 16 pigs were allotted to 2 treatments at d 7 post-weaning and fed a corn-soybean meal-based diet with no supplemental vitamin A. Treatments were control (no vitamins) and intramuscular injection with 3 mL VITAL E-A+D (STUARTPRODUCTS, Inc.) containing retinyl palmitate (RP; 300,000 IU), d-α-tocopherol (900 IU), and vitamin D3 (30,000 IU). All pigs were bled at d 0, 3, 7, and 14 post-injection and tissue samples were collected at d 7 and 14 post-injection (3 pigs/treatment). Data were analyzed by MIXED procedure of SAS. Plasma 25-hydroxycholecalciferol (3.44 vs. 71.00 ng/mL at d 3 post-injection) and retinol (0.09 vs. 0.18 µg/mL at d 3 post-injection) concentrations increased from d 3 to 14 post-injection (P < 0.05). Plasma RP was detected only in the vitamin treatment at d 3 and 7 post-injection (115.51 and 4.97 µg/mL, respectively). Liver retinol (0.63 vs. 19.10 µg/g at d 7 post-injection) and RP (43.33 vs. 199.13 µg/g at d 7 post-injection) concentrations increased at d 7 and 14 post-injection (P < 0.05) whereas those were not detected in the other tissues. The α-tocopherol concentrations increased in plasma (P < 0.05) at d 3 (0.99 vs. 17.14 µg/mL) and 7 post-injection and in liver (4.30 vs. 11.17 µg/g; P < 0.10), heart (4.60 vs. 24.80 µg/g; P < 0.10), and muscle (3.07 vs. 8.30 µg/g; P < 0.05) at d 7 post-injection. In conclusion, fat-soluble vitamin injection to nursery pigs increased plasma and liver status of α-tocopherol, retinol, and RP, and plasma 25-hydroxycholecalciferol concentrations. The α-tocopherol found in plasma post-injection was distributed to various tissues but RP only to the liver. Although plasma levels decreased post-injection, levels in liver increased for vitamins A and E, and vitamin E status was increased in all other tissues except brain.

PSV-22 Effects of different fat sources and vitamin E levels/isoforms on growth performance, antioxidant status, and fatty acid profile in the liver of pigs grown to 150 kg

The study objective was to assess the contribution of fat source and vitamin E (VE) supplementation on growth performance, antioxidant status, and fatty acid profile in the liver of pigs at heavy slaughter weight (148.09 ±1.64 kg). A total of 72 individually-fed pigs (36 barrows, 36 gilts; 28.55 ±1.16 kg) were randomly assigned to 12 dietary treatments in a 2 × 6 factorial arrangement. Fat treatments were tallow and corn-oil. The VE treatments included four levels of α-tocopheryl-acetate (ATA; 11, 40, 100, and 200 ppm) and two levels of mixed tocopherols (primarily γ-tocopherol; 40 and 100 ppm). Liver samples were collected at slaughter. Data analysis were performed by ANOVA using GLM in SAS. No effect of dietary fat sources, isoforms of VE, and levels of γ-tocopherol were detected on growth performance or liver antioxidant status (GSH, GSSG, SOD, and MDA). Increasing dietary ATA linearly increased overall ADG (0.98, 1.02, 1.02, and 1.08 kg/day; P = 0.02) from 28 to 150 kg; overall ADG of pigs fed γ-tocopherol-diets was 1.07 and 1.04 kg/day, respectively. An interaction between fat sources and ATA was observed on cumulative ADG during Phase1-3 (28-100 kg; P = 0.04) and Phase1-4 (28-125 kg; P = 0.03) wherein pigs fed corn-oil-diet, but not tallow-diet, had increased ADG with increased dietary ATA. Increasing dietary ATA quadratically increased SOD activity (P < 0.05; highest at 100 ppm), and quadratically decreased MDA content (P < 0.05; lowest at 40 ppm) in the liver. Liver fatty acid profile was affected by fat source (P < 0.05) but not VE treatment, pigs fed corn-oil-diets had less SFA (34.23 vs. 35.45%; P = 0.02) and MUFA (11.98 vs. 18.38%; P < 0.0001), but more PUFA (49.14 vs. 40.78%; P < 0.0001) than pigs fed tallow-diets in the liver. Beneficial effects of dietary VE supplementation were observed on growth performance and antioxidant status of pigs under conditions of this study.

Effect of different fat sources and vitamin E status/levels on growth performance, antioxidant status, carcass characteristics, fatty acid profile, and meat quality of pigs grown to heavy slaughter weight at 150 kg

Two experiments were used to evaluate the potential interaction of fat source and vitamin E (VE) in heavy slaughter weight pigs. In Experiment 1, a total of 64 individually-fed pigs (28.41 ± 0.83 kg) were randomly assigned to 8 dietary treatments in a 4×2 factorial arrangement. Fat treatments included cornstarch (CS), tallow (TW), corn-oil (CO), and coconut-oil (CN). VE treatments were dietary α-tocopheryl-acetate (ATA) at 11 and 200 ppm. In Experiment 2, a total of 72 individually fed pigs (28.55 ± 1.16 kg) were randomly assigned to 12 dietary treatments in a 2×6 factorial arrangement. Fat treatments were TW and CO. VE treatments included four levels of ATA (11, 40, 100, and 200 ppm) and two levels of mixed tocopherols (primarily γ-tocopherol; 40 and 100 ppm). VE deposition, growth performance, and meat quality were measured in both experiments. In both experiments, interaction between fat sources and VE were detected (P < 0.01) on plasma VE concentration, which increased (P < 0.01) with time and with increasing dietary VE, but increased faster (P < 0.05) in pigs fed with CN and TW compared to pigs fed CS and CO. Compared to CO, more saturated dietary fat sources (CN and TW) led to firmer belly (P < 0.01), which had more (P < 0.01) SFA and MUFA while less (P < 0.01) PUFA. In Experiment 1, increasing dietary ATA decreased (P < 0.05) FCR in Phase 4 and Phase 5. In Experiment 2, increasing dietary ATA increased overall ADG (linear, P = 0.02), with an interaction (P < 0.05) with fat sources on cumulative ADG during Phase1-4, wherein pigs fed CO, but not TW, had increased ADG with increasing dietary ATA. Increasing dietary ATA increased (quadratic, P < 0.05) liver SOD activity, and decreased (quadratic, P < 0.05) liver MDA content. The oxidative stability of loin was improved (P < 0.01) when dietary ATA increased over 40 ppm. In summary, both dietary fat source and VE supplementation affected the response measures.

PSV-23 Effects of different fat sources and vitamin E levels on tissue tocopherol concentration, antioxidant status, and fatty acid composition in the backfat of pigs grown to 150 kg

The study objective was to assess the contribution of fat source and vitamin E (VE) supplementation on tissue tocopherol concentration, antioxidant status, and fatty acid composition in the backfat of pigs at heavy slaughter weight (149.38 ±1.56 kg). A total of 64 individually-fed pigs (32 barrows, 32 gilts; 28.41 ±0.83 kg) were randomly assigned to 8 dietary treatments in a 4 × 2 factorial arrangement. Fat treatments included corn-starch (CS), tallow (TW), corn oil (CO) and coconut oil (CN). VE supplementation levels were 11 and 200 IU/kg. Loin muscle, backfat, and liver samples were collected at slaughter. Data analysis were performed by ANOVA using GLM in SAS. No interactions between dietary fat source and VE supplementation were observed. Increasing dietary VE level from 11 to 200 IU/kg increased (P < 0.001) the tocopherol concentration in both liver (4.73 vs. 21.06 ppm wet liver) and loin muscle (1.25 vs. 2.67 ppm wet muscle). Pigs from the CO group had higher liver SOD activity (P < 0.05) than the other treatments (CS 22.51, TW 22.67, CO 24.40, and CN 20.92 U/mg protein). Pigs from the CN group had the highest (P < 0.05) total saturated fatty acid content (CS 44.33, TW 40.33, CO 36.29, and CN 51.70%), but the lowest (P < 0.05) total polyunsaturated fatty acid content (CS 9.26, TW 9.80, CO 25.41, and CN 8.75%) and iodine value (CS 56.61, TW 60.66, CO 77.83, and CN 49.90) in the backfat. Pigs from the TW group had the highest (P < 0.05) total monounsaturated fatty acid content (CS 46.40, TW 49.87, CO 38.30, and CN 39.56%) in the backfat. Under conditions of this study, a higher level of VE supplementation increased liver and muscle tocopherol concentrations whereas dietary fat sources altered liver antioxidant activity and fatty acid composition in the backfat.

Antibiotic inclusion in the diet did not alter the standardized ileal digestible tryptophan to lysine ratio for growing pigs

Two 21-d experiments were conducted to determine the optimum standardized ileal digestible (SID) Trp:Lys ratio for growing pigs; 1 experiment fed diets supplemented with or without an antibiotic. The primary response variables in both experiments were ADG, ADFI, G:F, and plasma urea N (PUN) concentrations with the optimum SID Trp:Lys ratio detected using broken-line analysis. Experiment 1 evaluated the optimum SID Trp:Lys ratio in growing pigs fed diets supplemented with an antibiotic. This experiment used 120 crossbred pigs that were blocked by sex and initial BW (24.13 ± 2.72 kg) and allotted to 6 SID Trp:Lys ratios in 4 replicates. Dietary treatments were formulated by the addition of crystalline Trp to create 6 SID Trp:Lys ratios (13.08%, 14.06%, 15.04%, 17.00%, 18.95%, and 20.91%) with a constant SID Lys level of 0.655%. As SID Trp:Lys ratios increased, ADG, ADFI, and G:F increased, and PUN concentrations decreased linearly ( < 0.05) and quadratically ( < 0.05). Linear broken-line analysis yielded optimum SID Trp:Lys ratios of 17.93% ( < 0.001) and 16.17% ( = 0.009) for ADG and PUN, respectively, resulting in a mean optimum SID Trp:Lys ratio of 17.05%. Experiment 2 evaluated the optimum SID Trp:Lys ratio in growing pigs fed diets supplemented with or without an antibiotic. It used a total of 324 crossbred pigs (initial BW: 30.81 ± 3.56 kg) that were allotted to 6 SID Trp:Lys ratios in 6 replicates. Dietary treatments were formulated by the addition of crystalline Trp to create 6 SID Trp:Lys ratios (12.52%, 14.86%, 17.20%, 19.54%, 21.88%, and 24.22%) with a constant SID Lys level of 0.67%. As SID Trp:Lys ratios increased, ADG, ADFI, and G:F increased, and PUN concentrations decreased linearly ( < 0.001) and quadratically ( < 0.001) regardless of antibiotic inclusion. There were no differences by the antibiotic treatment in ADG, ADFI, G:F, or PUN concentrations ( > 0.49) and no interactions between antibiotics and Trp:Lys ratios ( > 0.29). When the data for all pigs were pooled for the various Trp:Lys ratios, the optimum SID Trp:Lys ratios for ADG and PUN based on linear broken-line analysis were 14.58% ( < 0.001) and 14.54% ( < 0.001), respectively, resulting in an optimum SID Trp:Lys ratio of 14.56% as the mean of the determined optima for ADG and PUN responses. These results demonstrate that the optimum SID Trp:Lys ratio for 30- to 50-kg growing pigs is not impacted by the dietary inclusion of an antibiotic as long as the diets are formulated on an SID AA basis.

Effect of combined xylanase and phytase on growth performance, apparent total tract digestibility, and carcass characteristics in growing pigs fed corn-based diets containing high-fiber coproducts

Phytate has been shown to be an antinutrient, and the feeding of high levels of phytase can break down phytate to improve nutrient utilization and pig performance. Dietary xylanase targets arabinoxylan breakdown, thereby improving energy utilization in pigs. However, the effects of simultaneous supplementation have not been clearly determined. Crossbred pigs ( = 45; mean initial weight, 26.4 ± 0.2 kg) were allotted to 1 of 9 treatments to evaluate the effects of both xylanase (endo-1,4-β xylanase [EC 3.2.1.8]) and phytase (6-phytase [EC 3.1.3.26]) supplementation as follows: 1) positive control (PC), a corn-soybean meal-based diet with 15% corn distillers dried grains with solubles, 15% wheat middlings, and 13% corn germ meal; 2) negative control (NC), ME was reduced by 103 kcal/kg from the PC diet by replacement of fat with corn starch; 3) NC + phytase (500 phytase units (FTU)/kg diet); 4) NC + phytase (1,000 FTU/kg diet); 5) NC + phytase (2,000 FTU/kg diet); 6) NC + xylanase (24,000 xylanase units [BXU]/kg diet); 7) NC + phytase (500 FTU/kg diet) + xylanase (24,000 BXU/kg diet); 8) NC + phytase (1,000 FTU/kg diet) + xylanase (24,000 BXU/kg diet); and 9) NC + phytase (2,000 FTU/kg diet) + xylanase (24,000 BXU/kg diet). All diets were formulated to meet nutrient requirements before phytase and xylanase addition to the diets. There were no significant interactions between xylanase and phytase supplementation on growth performance, carcass characteristics, and apparent total tract digestibility (ATTD). The ADG ( < 0.01, quadratic) and G:F ( < 0.05, linear) for the overall period increased as phytase level increased. The ATTD of P increased as phytase supplementation level increased ( < 0.05, linear and quadratic). The ATTD of DM, NDF, ether extract ( < 0.05), and hemicellulose ( = 0.05) increased quadratically as phytase level increased. Estimated carcass lean percentage and lean gain increased ( < 0.05, linear) as phytase level increased. Xylanase supplementation had no effect on growth performance, ATTD, and carcass characteristics. The results demonstrated an improved nutrient digestibility, performance, and carcass response to phytase supplementation beyond P provision because all diets exceeded current P requirement estimates based on standardized total tract digestible P.

Administration of vitamin D3 by injection or drinking water alters serum 25-hydroxycholecalciferol concentrations of nursery pigs

Objective

Two experiments were conducted to evaluate vitamin D₃ administration to nursery pigs by injection or in drinking water on serum 25-hydroxycholecalciferol (25-OHD₃) concentrations.

Methods

At weaning, 51 pigs (27 and 24 pigs in experiments 1 and 2, respectively) were allotted to vitamin D₃ treatments. Treatments in experiment 1 were: i) control (CON), no vitamin administration beyond that in the diet, ii) intramuscular (IM) injection of 40,000 IU of vitamin D₃ at weaning, and iii) water administration, 5,493 IU of vitamin D₃/L drinking water for 14 d postweaning. Treatments in experiment 2 were: i) control (CON), no vitamin administration, and ii) water administration, 92 IU of d-α-tocopherol and 5,493 IU of vitamin D₃/L drinking water for 28 d postweaning. The lightest 2 pigs within each pen were IM injected with an additional 1,000 IU of d-α-tocopherol, 100,000 IU of retinyl palmitate, and 100,000 IU of vitamin D₃.

Results

In both experiments, serum 25-OHD₃ was changed after vitamin D₃ administration (p<0.05). In experiment 1, injection and water groups had greater values than CON group through d 35 and 21 post-administration, respectively (p<0.05). In experiment 2, serum values peaked at d 3 post-administration in the injection groups regardless of water treatments (p<0.05) whereas CON and water-only groups had peaks at d 14 and 28 post-administration, respectively (p<0.05). Even though the injection groups had greater serum 25-OHD₃ concentrations than the non-injection groups through d 7 post-administration regardless of water treatments (p<0.05), the water-only group had greater values than the injection-only group from d 21 post-administration onward (p<0.05).

Conclusion

Serum 25-OHD₃ concentrations in pigs increased either by vitamin D₃ injection or drinking water administration. Although a single vitamin D₃ injection enhanced serum 25-OHD₃ concentrations greater than water administration in the initial period post-administration, a continuous supply of vitamin D₃ via drinking water could maintain higher serum values than the single injection.

Temporal plasma vitamin concentrations are altered by fat-soluble vitamin administration in suckling pigs

Piglets are born with purportedly low plasma vitamin D levels. The objective of this study was to investigate the effect of fat-soluble vitamin administration, primarily vitamin D, by different administration routes on plasma vitamin concentrations in suckling pigs. A total of 45 pigs from 5 litters were allotted at birth to 3 treatments within each litter. Pigs were administered 400 IU of α-tocopherol, 40,000 IU of retinyl palmitate, and 40,000 IU of vitamin D at d 1 of age either orally or by i.m. injection and compared with control pigs with no supplemental vitamin administration. Blood samples were collected at d 0 (initial), 1, 2, 3, 4, 6, 9, 14, and 20 after administration. Plasma 25-hydroxycholecalciferol (25OHD), α-tocopherol, retinyl palmitate, and retinol concentrations were analyzed. Except for retinol, the effects of treatment, day, and day × treatment interaction ( < 0.01) were observed on plasma vitamin concentrations. Plasma concentrations of 25OHD and α-tocopherol increased immediately regardless of administration routes to peak at d 2 and 1 after administration, respectively. Plasma retinyl palmitate concentrations increased only with the injection treatment, with the peak at d 1 after administration. Plasma concentrations of 25OHD in both administration treatments and α-tocopherol in the injection treatment were maintained at greater levels than those in the control treatment until d 20 after administration. With regard to the pharmacokinetic parameters for plasma 25OHD concentrations, the injection treatment had greater elimination half-life ( < 0.01), maximum plasma concentrations ( < 0.05), and all area under the curve parameters ( < 0.01) but a lower elimination rate constant ( < 0.01) than the oral treatment. Relative bioavailability of oral administration compared with injection administration was 55.26%. These results indicate that plasma status of 25OHD,α-tocopherol, and retinyl palmitate are differentially changed between types of vitamins administered and between administration routes and that the injection route had a greater increase and slower disappearance of plasma vitamin levels than the oral route during the suckling period.

Comparison of direct and indirect estimates of apparent total tract digestibility in swine with effort to reduce variation by pooling of multiple day fecal samples

The intent of this study was to establish a fecal sampling procedure for the indicator method (IM) to provide digestibility values similar to those obtained by the total collection (TC) method. A total of 24 pigs (52.6 ± 1.5 kg) were fed 1 of 4 diets with a 2 × 2 factorial arrangement of virginiamycin and phytase (PHY) added to a corn-soybean meal diet with no inorganic P supplement. Pigs were housed in metabolism crates for a 5-d TC period after 7 d of adaptation. Immediately after the TC, a fecal collection period followed, using the IM by including 0.25% of Cr2O3 in the feed for 10 d. Fecal collection for the IM started the day after diets containing Cr2O3 were first fed, and continued for 9 consecutive days with a single grab sample per day. Similar portions of feces from d 5 to 9 were also composited into 4 samples to evaluate multi-day pooling combinations. Highly variable means and CV among samples for apparent total tract digestibility (ATTD) were observed at d 1 and 2 using the IM. The mean ATTD for DM, GE, and nutrients appeared to be stabilized by d 5 or 6 in all dietary treatments. The TC data seemed to have lower CV than the IM data for many components. Based on the linear broken-line analysis, fecal Cr concentration plateaued at d 3.75 (P < 0.001) after the first feeding of Cr. Mean ATTD values by the IM were lower than those by the TC method for DM (P < 0.05), GE (P < 0.01), P (P < 0.01), and Ca (P < 0.001). The PHY supplementation improved ATTD of P (P < 0.001) and Ca (P < 0.001) in both collection methods, whereas the PHY effect on ATTD of DM was observed only for the IM (P < 0.05). Differences related to PHY effect on ATTD were detected from d 4 to 9 in a single grab sample for P and DM but the ATTD of DM had inconsistent P-values by day. Fecal sampling after 4 d of initial feeding of marker always allowed detection of treatment effects on ATTD of P but not on ATTD of DM. Results indicated that the IM results in lower digestibility values than the TC method and does not provide the same treatment difference as the TC digestibility for energy and nutrients that are not highly impacted by the dietary treatment. For the IM, ATTD values and fecal Cr concentration stabilize at least on d 5 after initial feeding of diets containing Cr2O3. At least 2-d pooling of feces for the IM appears to be needed to provide greater accuracy and lower variations than a single grab sample.

Intrauterine position affects fetal weight and crown-rump length throughout gestation

To investigate the effect of intrauterine positions on fetal growth throughout gestation, data from a total of 65 gilts (n = 784 fetuses) that were slaughtered at assigned days of gestation (d 43, 58, 73, 91, 101, and 108) on a project to evaluate fetal mineral deposition were used. Placenta units were removed from the uterus, and position, sex, weight, and crown-rump length (CRL) of each fetus were recorded. Fetuses were classified into 5 categories within a uterine horn for the absolute intrauterine position: the ovarian end (OE) of the uterine horn, next to the ovarian end (NOE), the middle (MD), next to the cervical end (NCE), and the cervical end (CE), and also classified for the relative fetal position with respect to the sex of adjacent fetuses. Fetuses at the OE and NOE of the uterine horn tended to be heavier (P = 0.06) and longer (P < 0.05) than those at the MD of the uterine horn at d 58 of gestation. Fetuses at the OE of the uterine horn were also heavier and longer than those at the MD and NCE of the uterine horn at d 101 and 108 of gestation (P < 0.05). Fetuses at the CE of the uterine horn were intermediate in weight and length. There were no major effects of adjacent fetal sex (fetuses surrounded by the opposite sexes) in weight or length. Male fetuses were heavier than female fetuses at d 43, 58, 73, and 108 of gestation (P < 0.05) and longer than female fetuses at d 58 (P = 0.06), 73 (P < 0.05), 101 (P = 0.07), and 108 (P < 0.05) of gestation. Fetal weight was highly correlated with CRL at all gestational ages (P < 0.01). These results indicate that 1) the absolute intrauterine position affects fetal growth more than the sex of the adjacent fetus in the uterine horn, 2) each end of the uterine horn (OE and CE) has heavier fetuses than the MD, and 3) male pigs grow faster than female pigs even before birth.

The Effects of Fat-soluble Vitamin Administration on Plasma Vitamin Status of Nursing Pigs Differ When Provided by Oral Administration or Injection

Four experiments were conducted to investigate the effect of fat-soluble vitamin administration to sows or newborn pigs on plasma vitamin status. In Exp. 1 and 2, a total of 24 and 43 newborn pigs were allotted to control and vitamin treatments (vitamin D3 with variable addition of vitamins A and E) orally or by i.m. injection. In Exp. 3, pigs from Exp. 2 were allotted to 2 treatments (±vitamins D3 and E in drinking water) for 14 d postweaning. In Exp. 4, twenty-four gestating sows were used for 2 treatments (±injection of a vitamin D3/A/E product 2 wk prepartum). In Exp. 1 and 2, when vitamin D3 was administrated orally or by i.m. injection on d 1 of age, pigs had increased plasma 25-hydroxycholecalciferol (25-OH D3) concentration 10 d after administration compared with control pigs (p<0.05). The injectable administration with vitamin D3 and E was able to achieve higher plasma 25-OH D3 (p<0.05) and α-tocopherol (p<0.05) concentrations than oral administration. At weaning, the pigs in the injection group had higher plasma 25-OH D3 concentration than those in the other groups in both studies (p<0.05). In Exp. 3, water supplementation of vitamin D3 and E postweaning increased plasma 25-OH D3 and α-tocopherol concentrations at d 14 postweaning (p<0.01). In Exp. 4, when sows were injected with the vitamin D3 product prepartum, serum 25-OH D3 concentrations of sows at farrowing (p<0.01), and in their progeny at birth (p<0.01) and weaning (p<0.05) were increased. These results demonstrated that fat-soluble vitamin administration to newborn pigs increased plasma 25-OH D3 concentration regardless of administration routes and α-tocopherol concentration by the injectable route, and that water supplementation of vitamin D3 and E to nursery pigs increased plasma 25-OH D3 and α-tocopherol concentrations. Additionally, injecting sows with vitamin D3 prepartum increased 25-OH D3 in sows and their offspring. If continued research demonstrates that the serum levels of 25-OH D3 are critical in weanling pigs, a variety of means to increase those levels are available to swine producers.

Gain recovery in a quantum dot semiconductor optical amplifier and corresponding pattern effects in amplified optical signals at 1.5 μm

Fast gain recovery observed in quantum-dot semiconductor-optical-amplifiers (QDSOAs) is useful for amplifying high-speed optical signals. The small but finite slow recovery component can deteriorate the signal amplification due to the accumulation of gain saturation during 10 Gb/s operation. A study of the gain recoveries and pattern effects in signals amplified using a 1.5 μm InAs/InGaAsP QDSOA reveals that the gain recovery is always fast, and pattern-effect-free amplification is observed at the ground state. However, at the excited state, the slow component increases with the current, and significant pattern effects are observed. Simulations of the pattern effects agreed with the observed experimental trends.

Estimation of relative defect densities in InGaN laser diodes by induced absorption of photoexcited carriers

Defects are one of the most important factors influencing the optical properties of groups III-V nitride semiconductor materials and thereby their applicability to light-emitting diodes. In this paper, we demonstrate that it is possible to estimate the presence of defects in InGaN laser diodes by performing pump-probe measurements and observing the induced absorptions. We have confirmed that the induced absorption originates from defects by performing experiments in which the pump intensity is varied. We believe that our method provides a powerful tool for evaluating the optical quality of InGaN materials before processing them into device fabrications.