Effects of providing a water-soluble globulin in drinking water and diet complexity on growth performance of weanling pigs

Two experiments were conducted to evaluate the effects of providing a water-soluble globulin in the drinking water on growth performance of weanling pigs. In Exp. 1, 360 weanling pigs (5.0 +/- 1.2 kg; 17 +/- 3 d of age; PIC) were blocked by initial weight and allotted to one of six treatments in a 2 x 3 factorial arrangement. Treatments included three diet complexity regimens with or without water-soluble globulin (3 and 1.5% solutions; d 0 to 7 and d 0 to 14, respectively) provided in the drinking water. The 35-d study was divided into three phases (d 0 to 7, 7 to 14, and 14 to 35) with corresponding lysine levels of 1.6, 1.5, and 1.35%. Soybean meal replaced specialty protein and lactose sources to provide three different complexity regimens. From d 0 to 7, a water-soluble globulin x diet complexity interaction (P < 0.05) was observed for average daily gain (ADG) and gain:feed (G/F). Increasing diet complexity increased ADG and G/F for pigs provided water, whereas the medium diet complexity regimen optimized performance for pigs offered water-soluble globulin. From d 0 to 14, pigs fed the two more complex regimens had greater ADG and G/F (P < 0.01) than the pigs fed the least complex regimen. Pigs offered water-soluble globulin had decreased (P < 0.01) ADFI, but increased (P < 0.001) G/F from d 0 to 14. For overall performance (d 0 to 35), increasing diet complexity increased (P < 0.03) ADG and ADFI, whereas water-soluble globulin offered from d 0 to 14 had no effect. In Exp. 2, 360 weanling pigs (5.2 +/- 1.6 kg; 19 +/- 4 d of age) were used in a 21-d growth assay. The trial was arranged as a 2 x 3 factorial with pigs fed the low- or medium-complexity diets (Exp. 1) with water or a 3% solution of water-soluble globulin offered for 4 or 8 d after weaning. From d 0 to 4, pigs offered water-soluble globulin had increased (P < 0.001) ADG and G/F compared with pigs provided water, whereas from d 4 to 8, pigs provided water had increased (P < 0.05) ADG and G/F compared with pigs offered water-soluble globulin. Pigs fed the medium-complexity diet had increased ADG and G/F (d 4 to 8 and d 8 to 12) compared with pigs fed the low-complexity diet. From d 0 to 8 and d 0 to 21, pigs provided water-soluble globulin for 4 or 8 d after weaning had improved G/F compared with pigs provided water. Results demonstrate that providing water-soluble globulin through the water source of weanling pigs improves ADG and G/F immediately after weaning.     

Effect of dietary levels of vitamin E (all-rac-tocopheryl acetate) with or without added fat on weanling pig performance and tissue alpha-tocopherol concentration

Two experiments involving 496 cross-bred pigs evaluated the efficacy of various dietary levels of vitamin E, with or without supplemental fat, on postweaning pig performance and weekly serum and terminal tissue alpha-tocopherol concentrations. The first trial involved 248 pigs weaned at an average of 15 d of age and 4.8 kg BW. The experiment was a randomized complete block design conducted in seven replicates. Vitamin E was added as dl-alpha-tocopheryl acetate at 0, 20, 40, 60, 80, 100, 150, or 200 IU/kg diet. Pigs were bled initially and at 7-d intervals for a 42-d period. Liver and s.c. adipose tissue samples were collected from six pigs per treatment group at 42 d. In Exp. 2, a 2 x 4 factorial arrangement of treatments in a randomized complete block design was conducted in seven replicates. The experiment used a total of 248 pigs weaned at 19 d of age and averaged 6.4 kg BW. Four vitamin E levels (0, 20, 40, and 60 IU/kg diet) and two added fat levels of 0 or 5% were fed for 35 d. Four pigs per treatment pen were bled weekly, and at 35 d a total of four pigs per treatment group were killed and liver, heart, and s.c. adipose tissues were collected and analyzed for alpha-tocopherol. The basal diet in both experiments contained an average 7.9 IU for period 1, and later diets averaged 11.0 IU vitamin E/kg. In both experiments serum alpha-tocopherol concentrations declined from weaning to 7 d after weaning and continued to decline each week after weaning when the basal diets were fed. Serum alpha-tocopherol concentrations increased (P < 0.01) each week as the dietary vitamin E level increased in both experiments. In Exp. 2, when fat was added to the diet serum alpha-tocopherol concentrations were higher (P < 0.01) than in diets without added fat. Liver, heart muscle, and adipose tissue alpha-tocopherol concentrations increased (P < 0.01) as vitamin E level increased, but at the higher dietary vitamin E level the liver surpassed the adipose tissue in its alpha-tocopherol concentration. Liver and adipose alpha-tocopherol concentrations were higher (P < 0.01) when fat was added to the diet. These results indicate that supplementation of 40 to 60 IU/kg diet with added fat resulted in a relatively constant balance of serum and tissue concentration of alpha-tocopherol during the nursery period, but when fat was not supplemented a dietary vitamin E level of 80 to 100 IU/kg diet may be needed. The current NRC recommendations for vitamin E for the pig from 5 to 20 kg BW may need to be reevaluated.     

Effect of vitamin E sources (RRR- or all-rac-alpha-tocopheryl acetate) and levels on sow reproductive performance, serum, tissue, and milk alpha-tocopherol contents over a five-parity period, and the effects on the progeny

Two dietary sources of vitamin E (DL-alpha-tocopheryl acetate [DL-beta-TAc], or D-alpha-tocopheryl acetate [DL-alpha-TAc]) at two dietary supplemental levels (30 vs 60 IU/kg) were evaluated in reproducing sows over a five-parity period. The experiment was a 2 x 2 factorial arrangement of treatments conducted as a randomized complete block in two replicates. A total of 48 gilts were fed their treatment diets from 40 kg BW through five parities, reflecting a total of 171 farrowings. Reproductive measurements of litter size, sow weight, and back-fat thickness were collected. The incidence of mastitis-metritis-agalactia (MMA) and fluid discharge from the vagina were evaluated for each sow on each of the first 3 d postpartum. Sows were bled at periodic intervals during gestation and at weaning (21 d) and serum was frozen. After the fifth parity, two to four sows from each treatment group were killed and tissues collected. At birth, two to three neonatal pigs were killed from each sow treatment group within each parity and livers were collected and frozen. In addition, three pigs from each litter from three to four sows per treatment group within each parity were bled at weaning and serum was saved. Six pigs from each sow group at weaning of Parity 5 were also killed and livers were collected and frozen. Sow and pig sera and tissues were analyzed for a-tocopherol. There was no effect (P > .15) of vitamin E source or level on the various sow reproductive measurements, litter size, or the incidences of MMA or fluid discharges from the vagina. Feeding D-alpha-TAc compared with DL-alpha-TAc or 60 IU compared with 30 IU vitamin E/kg diet resulted in higher (P < .01) sow serum, colostrum, and milk alpha-tocopherol contents at each measurement period. Sow liver, adipose, lung, and heart alpha-tocopherol contents were also higher (P < .01) when the 60 IU vitamin E level had been fed. Both serum and liver a-tocopherol contents in 21-d-old nursing pigs were higher (P < .01) when the sow had been fed D-alpha-TAc compared with the DL-alpha-TAc source or when the 60 IU level had been fed. There were no vitamin E source x vitamin E level interactions (P > .15) for the various alpha-tocopherol measurements. Although the supplemental vitamin E sources were provided on an equivalent IU basis, these results suggest that D-alpha-TAc has a higher equivalency than DL-alpha-TAc on an IU basis, but higher dietary levels also resulted in higher sow and pig alpha-tocopherol contents.     

Relative bioactivity of dietary RRR- and all-rac-alpha-tocopheryl acetates in swine assessed with deuterium-labeled vitamin E

This study evaluated the relative bioactivities of natural and synthetic stereoisomers of alpha-tocopherol in swine. Deuterium-labeled vitamin E (150 mg each of d3-RRR- [natural] and d6-all-rac- [synthetic] alpha-tocopheryl acetates) was administered orally to adult female pigs (n = 3) with the morning feed. Blood samples were obtained at 0, 3, 6, 9, 12, 36, 48, and 72 h after the dose. The time of maximum plasma d3-alpha-tocopherol concentration (0.486 microg/mL) occurred at 12 h, and d6-alpha-tocopherol peaked earlier (at 9 h) and at a lower (P < 0.05) concentration (0.288 microg/mL). The d3-/d6-alpha-tocopherol ratio increased from 1.35 (SD = 0.73) at 3 h after dosing to 2.0 (SD = 0.14) at 72 h (P = 0.03). The plasma disappearance rates of d3- and d6-alpha-tocopherols (post-maximum concentrations) were similar and were estimated to be 0.013 microg/mL per hour. In summary, swine discriminated between RRR- and all-rac-alpha-tocopherols, which resulted in an approximately twofold higher plasma alpha-tocopherol concentration arising from the RRR-form. This 2:1 ratio of RRR- to all-rac- is higher than the currently accepted USP definition of RRR-:all-rac- of 1.36:1.00.     

Effect of vitamin E and copper on the vitamin E status and performance of growing pigs

A 13-wk trial was conducted with 32 pigs to determine the effects of dietary Cu (250 ppm) and alpha-tocopheryl acetate (ATA, 22 IU/kg) on the performance, serum enzymes, serum and tissue tocopherols, and antibody production in growing pigs. Pigs were fed corn-soybean meal diets containing 21% CP the first 4 wk and 18% CP during the rest of the trial. All feed was stored a minimum of 14 d before it was fed. The addition of Cu decreased (P less than .01) the concentration of alpha-tocopherol in the feed. alpha-Tocopherol concentrations were less than .01 mg/kg in the starter diet and less than 2 mg/kg in the grower diet after 14 d of storage. Supplemental Cu or ATA had no effect on ADG, feed intake, or gain:feed during the first 4 wk. During wk 5 to 13, the addition of Cu to diets containing no ATA increased daily feed intake and decreased gain:feed, but with ATA addition, feed intake decreased and gain:feed increased, resulting in a Cu x ATA interaction (P less than .05). The addition of Cu or ATA had no effect (P greater than .1) on serum glutathione peroxidase or lactic dehydrogenase activity. Serum tocopherols were reduced (P less than .05) by the addition of Cu during wk 1 to 4, 6 (P less than .01), and 7 (P less than .05) and increased (P less than .01) by ATA addition during the entire experiment. The addition of ATA increased the tocopherol concentrations in bile, ham, heart, pancreas, kidney, spleen, liver, psoas and longissimus muscle (P less than .01), kidney fat, backfat, and adrenal gland (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluating the antioxidant status of weanling pigs fed dietary vitamins A and E

Two experiments evaluated the relationship of vitamin E (source and level) and vitamin A (level) on the apparent absorption and retention of both vitamins in weaned pigs. Both experiments used a combined total of 460 crossbred pigs ([Yorkshire x Landrace] x Duroc), housed in elevated 1.2- x 1.2-m crates containing five pigs per pen. Experiment 1 was a 2 x 2 x 2 factorial arrangement of treatments in a randomized complete block design conducted in seven replicates. Levels of vitamin A (2,200 or 13,200 IU/kg), vitamin E (15 or 90 IU/kg), and two vitamin E sources (D-alpha-tocopheryl acetate [D-TAc] or DL-alpha-tocopheryl acetate [DL-TAc]) were evaluated over a 35-d period. Vitamin A or E levels and the two vitamin E sources did not affect pig performances to 20 kg BW. Serum retinol and alpha-tocopherol concentrations increased (P < 0.01) as the dietary level of each vitamin increased. Serum alpha-tocopherol declined as dietary vitamin E level increased when vitamin A level increased resulting in an interaction (P < 0.05). Serum alpha-tocopherol concentrations were higher (P < 0.05) at 35-d postweaning when D-TAc was the vitamin E source. Experiment 2 was a 3 x 2 factorial arrangement of treatments conducted in six replicates. Three levels of vitamin A (2,200, 13,200, or 26,400 IU/ kg) and two sources of vitamin E (D-TAc or DL-TAc) each provided at 40 IU/kg diet were evaluated over a 35-d period. Pig performances to 35-d postweaning were not affected by the dietary variables. Serum alpha-tocopherol (P < 0.01) and retinol (P < 0.05) concentrations increased as their respective vitamin level increased. Serum (P < 0.05) and liver (P < 0.01) alpha-tocopherol concentrations both declined as dietary vitamin A levels increased resulting in interaction responses. Serum alpha-tocopherol concentration was higher (P < 0.05) at 35-d postweaning when d-TAc was the vitamin E source. Dietary vitamin E sources had no effect on serum or liver retinol concentrations. These results demonstrated that both supplemental vitamin A and vitamin E increased in the blood as their dietary levels increased. However, as dietary vitamin A level increased, serum and liver alpha-tocopherol concentrations declined, suggesting a reduced absorption and retention of alpha-tocopherol when weaned pigs were fed high dietary vitamin A levels.     

Responses in egg shell quality to sodium chloride supplementation of the diet and/or drinking water

1. Supplementing the drinking water of 50-week-old laying hens with sodium chloride (NaCl) concentrations between 0.5 and 2 g/l for 7 weeks significantly increased the incidence of egg shell defects and significantly decreased egg shell quality. Dietary NaCl concentrations between 0 and 2 g/kg had little effect on this response. 2. At similar total NaCl intakes egg shell defects were much greater when the NaCl was obtained from the drinking water rather than from the diet. 3. Hens producing eggs with defective shells as a result of receiving saline drinking water failed to recover the ability to lay eggs with good shells after 8 weeks on normal water. 4. The increased incidence of shell damage was not related to decreased food intake or increased egg weight or production.     

Response of growing-finishing pigs to decreasing floor space allowance and(or) virginiamycin in diet

Five hundred forty crossbred pigs were utilized in four trials (10 replications) at two stations to determine the separate and interacting effects of decreasing floor space allowance with or without the addition of virginiamycin to the diet on performance of growing-finishing pigs. Pigs were allowed .37, .33 or .28 m2/pig during the growing phase (23 to 55 kg) and .74, .66, .56 m2/pig during the finishing phase (55 to 100 kg) and fed either a corn-soybean meal control diet or the control diet plus 11 mg of virginiamycin/kg of diet. Floor space allowances were achieved by varying pen size, so the number of pigs and feeder space per pig were constant for all pens. During the growing phase, daily gain (P less than .01) daily feed intake (P less than .05) and feed conversion ratio (P less than .05) decreased as floor space allowance decreased. During the finishing phase and for the total test period, daily gain (P less than .01) and feed conversion ratio (P less than .05) were reduced but daily feed intake was not affected (P greater than .05) by restricted floor space allowance. The addition of virginiamycin to the diet had no effect on pig performance. The virginiamycin X floor space allowance interaction was not significant, suggesting that pigs fed a diet with or without virginiamycin responded similarly to restricted floor space allowance. The data suggest that the addition of virginiamycin to the diet was ineffective in overcoming the decrease in performance of growing-finishing pigs caused by crowded conditions.     

Supplementation of carbohydrases or phytase individually or in combination to diets for weanling and growing-finishing pigs

The overall objective of the studies reported here was to evaluate the growth and nutrient utilization responses of pigs to dietary supplementation of phytate- or nonstarch polysaccharide-degrading enzymes. In Exp. 1, growth performance and nutrient digestibility responses of forty-eight 10-kg pigs to dietary supplementation of phytase or a cocktail of xylanase, amylase, and protease (XAP) alone or in combination were evaluated. The growth response of one hundred fifty 23-kg pigs to dietary supplementation of phytase or xylanase individually or in combination was studied in Exp. 2 in a 6-wk growth trial, whereas Exp. 3 investigated the nutrient digestibility and nutrient retention responses of thirty 24-kg pigs to dietary supplementation of the same enzymes used in Exp. 2. In Exp. 1, the pigs were used in a 28-d feeding trial. They were blocked by BW and sex and allocated to 6 dietary treatments. The treatments were a positive control (PC) diet; a negative control (NC) diet marginally deficient in P and DE; NC with phytase added at 500 or 1,000 phytase units (FTU)/kg; NC with xylanase at 2,500 units (U)/kg, amylase at 400 U/kg, and protease at 4,000 U/kg; and NC with a combination of phytase added at 500 FTU/kg and XAP as above. In Exp. 2 and 3, the 5 dietary treatments were positive control (PC), negative control (NC), NC plus 500 FTU of phytase/kg, NC plus 4,000 U of xylanase/kg, and NC plus phytase and xylanase. In Exp. 1, low levels of nonphytate P and DE in the NC diet depressed (P < 0.05) ADG of the pigs by 16%, but phytase linearly increased (P < 0.05) ADG by up to 24% compared with NC. The cocktail of XAP alone had no effect on ADG of pigs, but the combination of XAP and phytase increased (P < 0.05) ADG by 17% compared with the NC treatment. There was a linear increase (P < 0.01) in Ca and P digestibility in response to phytase. In Exp. 2, ADG was 7% greater in PC than NC (P < 0.05); there were no effects of enzyme addition on any response. In Exp. 3, addition of phytase alone or in combination with xylanase improved (P < 0.05) P digestibility. Phosphorus excretion was greatest (P < 0.01) in the PC and lowest (P < 0.05) in the diet with the combination of phytase and xylanase. The combination of phytase and xylanase improved P retention (P < 0.01) above the NC diet to a level similar to the PC diet. In conclusion, a combination of phytase and carbohydrases improved ADG in 10-kg but not 23-kg pigs, but was efficient in improving P digestibility in pigs of all ages.     

Influence of sodium diethyldithiocarbamate (Imuthiol) on lymphocyte function and growth in weanling pigs

Mitogen-stimulated lymphocyte proliferation, delayed-type hypersensitivity (DTH) reactions, interleukin-2 (IL-2) production, and growth performance were evaluated in 3-week-old pigs treated with imuthiol. Lymphocyte proliferative responses to Con A and PWM were reduced (P < 0.05) in pigs treated with imuthiol at 25 mg/kg; PHA proliferative responses were not influenced by imuthiol treatment. Imuthiol at 2.5 mg/kg and 25 mg/kg lowered IL-2 production when compared to saline-treated controls. Delayed-type hypersensitivity responses to PHA were higher in 25 mg/kg imuthiol-treated pigs; however, 2.5 mg/kg imuthiol-treated pigs had lower DHT reactions. Imuthiol at 2.5 mg/kg and 25 mg/kg reduced (P < 0.05) average daily feed intake. These data suggest that in vivo imuthiol treatment in pigs lowers lymphocyte proliferative responses, IL-2 production, and growth performance.     

Lack of influence of nursery temperature on the response of weanling pigs to supplemental vitamins C and E

Three trials using 240 weanling pigs were conducted during winter months to determine the influence of nursery temperature ("comfortable" vs "cold") on the response of weanling pigs to added vitamin C (700 ppm) or E (55 IU/kg) to a corn-soybean meal diet. A "comfortable" temperature schedule (27 C initially with a weekly 2 C drop) was maintained in one nursery, with the temperature schedule in the "cold" nursery about 8 C lower. Plasma concentrations of vitamin C and vitamin E were elevated when the respective vitamins were added to the diet, but were not consistently influenced by nursery temperatures. Daily gain, daily feed intake and feed efficiency were not improved with the added C or E. Daily feed intake was increased and feed-to-gain ratios were larger for pigs housed in the "cold" nursery compared with pigs housed in the "comfortable" nursery; however, daily gains were similar in the two environments. Pigs housed in the "cold" nursery were slightly stressed, as indicated by heavier adrenal glands, but the antibody response and serum glucocorticoid concentrations were not significantly affected by either diet or temperature.     

The generalized Shwartzman reaction induced by a single injection of endotoxin in pigs fed 2 vitamin E deficient commercial diet.

An experimental generalized Shwartzman reaction (GSR) induced in pigs by endotoxin from Escherichia coli has been reported previously (Teige et al. 1973, Quast 1973). The diet given to the pigs seemed to influence the outcome of the experiments. It has been found difficult to provoke GSR in pigs fed a commercial diet, even when the E. coli endotoxin is given as a single, relatively large dose or as 2 properly spaced doses (Teige et al., Nordstoga 1976). Quast induced the GSR by continuous infusion of endotoxin. In connection with 1 experiment in pigs, changes indicative of GSR were observed among a group of animals fed a commercial diet and receiving a small single dose of endotoxin. These observations are presented in this paper.     

Increased indices of lipid peroxidation in stress-susceptible pigs and effects of vitamin E

When stress-susceptible and stress-resistant pigs consumed diets containing 10 iu vitamin E kg-1, the stress-susceptible pigs had damaged cell membranes. This was indicated by increased plasma activities of creatine kinase and pyruvate kinase. Plasma concentrations of thiobarbituric acid reactive substances and conjugated dienes were also increased suggesting that the membrane damage was caused by free radicals. Susceptibility to free radicals was further demonstrated by an increased tendency for erythrocytes and tissue homogenates from stress-susceptible pigs to peroxidise when incubated with hydrogen peroxide and iron, respectively. Supplementation of the diets with approximately 20 times normal requirements of vitamin E decreased plasma creatine kinase and pyruvate kinase activities, and inhibited the formation of the indices of peroxidation in vivo and in vitro. It is concluded that the stress-susceptible pig has an abnormality in its antioxidant defence mechanisms. However, this abnormality was not due to a deficiency in selenium-dependent glutathione peroxidase, since activities were significantly increased in the longissimus dorsi of stress-susceptible pigs. Although the nature of the antioxidant defect is unclear, it is suggested that stress-susceptible pigs are under a sustained oxidant stress and that a decreased ability to accommodate even a normal free radical load may contribute to the rapid development of the fatal stress response.     

Effect of vitamin E and selenium on iron utilization in neonatal pigs.

Supplying adequate iron (Fe) to neonatal pigs to support normal growth and hematological and antioxidant status, while preventing iron toxicity, is a challenge for producers. Three experiments were conducted to determine the effect of frequency and route of Fe administration with or without vitamin E (E) and selenium (Se) on growth, Fe, and antioxidant status of neonatal pigs. In Exp. 1, 12 pigs from dams with reduced E status were fed a semipurified diet without added Fe from d 3 to d 14 of age. At d 6 of age, pigs received the following i.m. injections: 1) FE, 1 mL containing 200 mg of Fe (iron dextran); 2) FEE, treatment FE plus 1 mL containing 300 IU of vitamin E (d-alpha tocopherol); or 3) FESEE, 1.03 mL containing 200 mg of Fe (iron dextran), .15 mg of Se (sodium selenite), and 15 IU of vitamin E (d-alpha tocopherol). Pigs were weighed daily and blood was collected at 3, 7, and 14 d of age. From d 8 to 14, growth was depressed (P < .05) in pigs injected with FESEE. At 14 d of age, pigs injected with FE or FEE had increased (P < .05) hemoglobin (Hb) concentration. Ceruloplasmin activity (CP) was greater (P < .05) at d 7 of age than at d 3 or 14 regardless of treatment. In Exp. 2, 3-d-old pigs (n = 94) received the following: 1) FE, 200 mg Fe (iron dextran) i.m.; (2) FEE, treatment FE plus 300 IU vitamin E i.m.; 3) EFE, 300 IU vitamin E i.m. followed by 200 mg Fe (iron dextran) i.m. 24 h later; or 4) OFE, 100 mg Fe and 10 mg Cu orally. On d 21 of age, one-half of the pigs in each treatment received a second dose of their respective treatment. Blood samples (n = 60) were obtained on d 3 and 21 of age. Pigs injected with FE, FEE, or EFE had greater (P < .05) Hb at d 21 than pigs given OFE. Copper/zinc superoxide dismutase (Cu/ZnSOD) activity was greater (P < .05) at d 21 with OFE than with the other treatments. At 65 d of age, ADG did not differ among treatments. In Exp. 3, pigs (n = 150, in three farrowing groups) were injected with 200 mg of Fe (iron dextran) on d 1 or d 1 and 14. Blood samples were obtained on d 7 and 21 of age. Hemoglobin concentration on d 21 was improved equally by both treatments. Catalase and Cu/ZnSOD activities were increased (P < .05) on d 21 of the experiment compared with d 7 regardless of treatment. Growth was not affected by injection frequency. Results from these experiments indicate that one Fe injection (200 mg) for pigs from sows fed adequate vitamin E will result in adequate growth and hemoglobin concentration with today's improved genetics.     

The effect of dietary vitamin D supplementation on sodium-dependent phosphate uptake and expression of NaPi-IIb in the small intestine of weanling pigs

Two experiments were conducted to investigate the effects of 1,25(OH)₂D₃ to stimulate Na⁺-dependent phosphate uptake in Caco-2 cells, and the effects of dietary vitamin D supplementation to vitamin D-deficient nursery pigs on Na⁺-dependent nutrient uptake and mRNA expression of NaPi-IIb cotransporter and calbindin D9k in the jejunum. In Exp. 1, 250,000 Caco-2 cells were seeded on Costar 12 mm Snapwell inserts with a 0.40 µm polycarbonate filter and a seeding density of 0.25 × 10⁶ and studied at 15 d postconfluence. Cells were treated with 10 nM of either 1,25(OH)₂D₃ or vehicle for 48 h and then mounted in modified Ussing chambers for transepithelial measurements. In Exp. 2, pigs (n = 32) were removed from sows at 3 d of age, placed on a vitamin D-deficient milk replacer diet and housed in a room devoid of sunlight and UV light in the range of 280 to 300 nm. On day 28, serum 25(OH)D₃ concentrations were measured to verify low vitamin D status. Pigs (BW 10.10 ± 0.38 kg) were then individually housed day 28 postweaning and allotted to 1 of 2 dietary treatments. Dietary treatments consisted of corn-soybean-based diets with vitamin D supplementations of 0 or 1,500 IU/kg diet for 12 d. Blood samples were taken from the brachiocephalic vein on the initial (day 0) and final day (day 10, 11, or 12) of the study for analysis of serum 25(OH)D₃, P, and Ca. Pigs were euthanized and jejunal segments were harvested and used in modified Ussing chambers and for RNA isolation and subsequent quantitative RT-PCR analysis. In Exp. 1, treating Caco-2 cells with 10 nM 1,25(OH)₂D₃ resulted in a 52% increase (P < 0.005) in Na⁺-dependent phosphate uptake compared with cells treated with a vehicle. In Exp. 2, Na⁺-dependent phosphate and glucose transport did not differ (P > 0.10) among treatment groups. Additionally, NaPi-IIb and calbindin D9k mRNA expression were not different (P > 0.10) between treatment groups. No differences (P > 0.10) were detected in final serum P or 25(OH)D₃ concentrations between treatments. However, serum Ca linearly increased (P < 0.05) as the concentration of supplemental vitamin D increased in the diet. Overall, while 1,25(OH)₂D₃ stimulated Na⁺-dependent phosphate uptake in Caco-2 cells, supplementing diets with 1,500 IU/kg vitamin D₃ from cholecalciferol did not increase jejunal Na⁺-dependent phosphate uptake or NaPi-IIb mRNA expression over that of pigs fed diets with no supplemental cholecalciferol.     

Oxygenated drinking water enhances immune activity in pigs and increases immune responses of pigs during Salmonella typhimurium infection

It has been considered that drinking oxygenated water improves oxygen availability, which may increase vitality and improve immune functions. The present study evaluated the effects of oxygenated drinking water on immune function in pigs. Continuous drinking of oxygenated water markedly increased peripheral blood mononuclear cell proliferation, interleukin-1β expression level and the CD4(+):CD8(+) cell ratio in pigs. During Salmonella Typhimurium infection, total leukocytes and relative cytokines expression levels were significantly increased in pigs consuming oxygenated water compared with pigs consuming tap water. These findings suggest that oxygenated drinking water enhances immune activity in pigs and increases immune responses of pigs during S. Typhimurium Infection.