Effects of porcine somatotropin administration on the responses to dietary lysine and a near-ideal blend of amino acids on the amino acid composition of whole-body protein and amino acid accretion rate in growing pigs.

An experiment was conducted to assess the effects of porcine somatotropin (pST) on the responses to a near-ideal blend of AA on the AA composition of empty, whole-empty body (WEB) protein and WEB essential AA accretion rate in pigs from 22 to 60 kg BW. Forty Hampshire × Yorkshire gilts were individually penned and assigned to a 4 × 2 factorial arrangement of treatments consisting of four diets with and without pST injection. A fortified corn-soybean meal basal diet was formulated to contain 1.50% total Lys with Thr, Met, and Trp added to obtain a near-ideal blend of these AA relative to Lys. In three additional diets, Lys was reduced to 1.25%, 1.00%, and 0.75% by diluting the basal diet with cornstarch, cellulose, and sand such that the diets also contained the same ratios of AA. Pigs that received pST were administered a daily i.m. injection of 2 mg of pST. At 60 kg BW, the WEB (carcass, head, viscera, blood, nails, and hair) was ground and analyzed for proximate and AA composition. Administration of pST increased (P < 0.001) accretion rates of WEB protein and essential AA. Increasing dietary essential AA increased (quadratic, P < 0.03) accretion rate of WEB protein, His, Leu, Trp, and Val in pST-treated pigs, but not in untreated pigs. Lysine composition in the accreted WEB protein was not affected (P > 0.05) by dietary Lys. The efficiency of Lys utilization for WEB Lys accretion was linearly affected (P < 0.01) by dietary Lys. These results indicated that the dietary Lys needed to achieve maximum WEB Lys accretion is markedly increased by pST administration.

This study evaluated the effects of two factors, porcine somatotropin and graded levels of amino acids, on the total accumulation and the accretion rate of amino acids across a broad range of protein deposition rates in growing pigs. Treatments included 1) with or without a daily injection of porcine somatotropin and 2) graded levels of total dietary lysine from 0.75% to 1.50%. As expected, both the administration of porcine somatotropin and increased dietary lysine increased both the amount and the rate of amino acid accretion. However, the amount and rate of amino acid accretion from increased dietary amino acids were markedly greater in pigs treated with porcine somatotropin. Thus, the extent to which the genetic potential for protein deposition is achieved depends on both the anabolic capacity of the pig and the amino acid concentration of the diet provided.

Effects of a second iron-dextran injection administered to piglets during lactation on differential gene expression in liver and duodenum at weaning.

Six female littermate piglets were used in an experiment to evaluate the mRNA expression in tissues from piglets given one or two 1 mL injections of iron dextran (200 mg Fe/mL). All piglets in the litter were administered the first 1 mL injection < 24 h after birth. On day 7, piglets were paired by weight (mean body weight = 1.72 ±â€…0.13 kg) and one piglet from each pair was randomly selected as control (CON) and the other received a second injection (+Fe). At weaning on day 22, each piglet was anesthetized, and samples of liver and duodenum were taken from the anesthetized piglets and preserved until mRNA extraction. differential gene expression data were analyzed with a fold change cutoff (FC) of |1.2| P < 0.05. Pathway analysis was conducted with Z-score cutoff of P < 0.05. In the duodenum 435 genes were significantly changed with a FC ≥ |1.2| P < 0.05. In the duodenum, Claudin 1 and Claudin 2 were inversely affected by + Fe. Claudin 1 (CLDN1) plays a key role in cell-to-cell adhesion in the epithelial cell sheets and was upregulated (FC = 4.48, P = 0.0423). Claudin 2 (CLDN2) is expressed in cation leaky epithelia, especially during disease or inflammation and was downregulated (FC = -1.41, P = 0.0097). In the liver, 362 genes were expressed with a FC ≥ |1.2| P < 0.05. The gene most affected by a second dose of 200 mg Fe was hepcidin antimicrobial peptide (HAMP) with a FC of 40.8. HAMP is a liver-produced hormone that is the main circulating regulator of Fe absorption and distribution across tissues. It also controls the major flows of Fe into plasma by promoting endocytosis and degradation of ferroportin (SLC4A1). This leads to the retention of Fe in Fe-exporting cells and decreased flow of Fe into plasma. Gene expression related to metabolic pathway changes in the duodenum and liver provides evidence for the improved feed conversion and growth rates in piglets given two iron injections preweaning with contemporary pigs in a companion study. In the duodenum, there is a downregulation of gene clusters associated with gluconeogenesis (P < 0.05). Concurrently, there was a decrease in the mRNA expression of genes for enzymes required for urea production in the liver (P < 0.05). These observations suggest that there may be less need for gluconeogenesis, and possibly less urea production from deaminated amino acids. The genomic and pathway analyses provided empirical evidence linking gene expression with phenotypic observations of piglet health and growth improvements.

Iron deficiency anemia (IDA) in neonatal piglets is a problem that occurs unless there is intervention with exogenous iron. The most common method to prevent IDA is with an iron injection within 48 h of birth. However, the iron from the first injection will only support normal iron status in the piglets for ~4 kg of growth. As a result, with faster-growing piglets and larger litters, many piglets weaned today are iron deficient which results in slower growth and poor immunity. Pigs never fully recover nor grow at the same rate as those that have sufficient iron status. The aim of this study was to evaluate the effects of one or two injections of iron dextran on the differences in gene expression and metabolic pathway changes in the small intestine and liver of nursing piglets. At weaning, samples of liver and duodenum underwent genome-wide RNA sequencing. The data obtained were statistically analyzed to determine which genes and metabolic pathways were affected. There were 362 and 435 genes significantly changed in the liver and duodenum, respectively, due to a second dose of iron dextran on day 7 after birth.

A second iron injection administered to piglets during lactation improves hemoglobin concentration, growth performance, and carcass characteristics at slaughter.

An experiment was conducted to evaluate the effects of a second injection of iron dextran administered on days 6 to 8 of age. A total of 144 crossbred pigs (equal barrows and gilts; initial age 6 to 8 d; initial body weight [BW] = 2.86 ± 0.01 kg) were assigned to either the control (CON) or an added-injection treatment (+Fe). Pigs were paired by sex and BW within a litter and randomly assigned to the iron treatment within each pair. All pigs had received an initial intramuscular (IM) injection of iron dextran (200 mg Fe) <24 h after birth. Pigs assigned to the +Fe treatment received a second IM injection of iron dextran (200 mg Fe) on days 6 to 8. All pigs were weaned at 22 to 25 d, housed 6 pigs/pen, and received a common corn-soybean meal diet. BW and feed disappearance were recorded every 2 wk. Hemoglobin (Hb) concentrations were measured at birth, initiation of experiment (days 6 to 8), weaning, and the end of the nursery and end of the study. At the end of the study, 1 pig/pen (n = 12 pigs/treatment), closest to the pen mean was selected and slaughtered for carcass characteristic measures. The individual pig served as the experimental unit for BW, Hb, average daily gain (ADG), and carcass characteristic data whereas the pen served as the experimental unit for average daily feed intake, and gain/feed ratio data. The +Fe pigs had a greater Hb at weaning (13.1 vs. 10.7 g/dL, respectively; P < 0.01) and end of the nursery (12.1 vs. 11.7 g/dL, respectively; P = 0.01) compared to CON pigs. During the finisher period, +Fe pigs had a greater ADG (0.94 vs. 0.91 kg, respectively; P = 0.05) compared to CON pigs. Overall, pigs receiving the second iron injection had an ~4% increase in ADG (P = 0.04) from weaning to the end of study. The cumulative improvement in ADG from weaning to the end of study observed for +Fe group resulted in +Fe pigs having a heavier BW at the end of the study (~3 kg; P = 0.04). Following slaughter, +Fe pigs had ~7.2% heavier trimmed loin (P = 0.04) compared to the CON pigs. In conclusion, administering a second iron injection resulted in greater Hb at weaning and the end of the nursery as well as improved growth performance from weaning to the end of study weight and increased carcass weight at slaughter.

The study aimed to evaluate the effects of a second iron dextran injection administered to piglets before weaning on hemoglobin concentration (Hb), growth performance, and carcass measures. Treatments included: a single iron injection administered within 24 h after birth (CON) and two iron injections (+Fe), one administered within 24 h after birth followed by a second iron injection administered 6 to 8 d after birth. Administering a second iron injection before weaning resulted in increased Hb at weaning and the end of the nursery period. Furthermore, pigs receiving a second iron injection had a greater average daily gain from weaning to final market weight which resulted in a final bodyweight difference of ~3 kg. The increased slaughter weight observed for pigs receiving a second iron injection was associated with an increase in trimmed loin yield. In the current study, providing a second iron injection before weaning was a practical method to improve weaning Hb in early life and resulted in a faster overall growth from weaning to the end of the study.

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  ±â€…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.

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 ±â€…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.

Standardized ileal digestibility of amino acids differs among sources of bakery meal when fed to growing pigs.

A multistate experiment involving universities in IL, IN, KY, and MN was conducted as a part of the research efforts by the North-Central Coordinating Committee-42 on swine nutrition. The null hypothesis that there are no differences in the standardized ileal digestibility (SID) of amino acids (AA) among different sources of bakery meal was tested. Eleven sources of bakery meal were procured from swine-producing states in the United States and each source was included in one diet as the sole source of AA. A N-free diet was prepared as well. Diets were prepared in one batch and divided into four sub-batches that were subsequently distributed to the four participating universities. At each university, diets were fed to 12 pigs that had a T- cannula installed in the distal ileum. Pigs were allotted to incomplete Latin square designs with 12 pigs and 4, 5, or 6 periods for a total of 21 replicate pigs per diet. Each period lasted 7 d with ileal digesta being collected from the cannulas on days 6 and 7. Samples were analyzed for AA and the SID of each AA was calculated. Results indicated that there were differences (P < 0.001) in the SID of all AA except Pro among the 11 sources of bakery meal. The differences in SID of AA observed in this experiment were greater than what is usually observed among sources of the same ingredient, indicating that there is more variability among sources of bakery meal than among different sources of other ingredients. This is likely a consequence of different raw materials being used in the production of different sources of bakery meal. Regardless of source of bakery meal, the AA with the least SID was Lys indicating that some of the raw materials in the product streams used to generate the bakery meals may have been overheated. Additionally, the Lys:crude protein ratio in each source of bakery meal was not a good predictor of the SID of Lys, which likely reflects the different raw materials being included in the different meals. In conclusion, the SID of AA varies among different sources of bakery meal and the SID of Lys is less than the SID of all other indispensable AA.

Eleven sources of bakery meal were used in a regional experiment to determine digestibility of amino acids. Diets containing each source of bakery meal were prepared at one university and distributed to three other universities. Diets were fed to pigs that had a cannula installed in the distal ileum and ileal digesta were collected from pigs for 2 d following 5 d of adaptation. Results indicated that there is considerable variation in the digestibility of all amino acids among sources of bakery meal, which is likely a reflection of differences in raw material use among different producers of bakery meal. Results also demonstrated that the digestibility of Lys is less than the digestibility of all other amino acids, indicating that some of the raw materials used in the production of bakery meal may have been heat damaged. It may, therefore, be necessary to add additional Lys to diets containing bakery meal.

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 ±â€…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.

The study evaluated vitamin E (VE) supplementation and fat source on fatty acid (FA) composition and VE concentrations in pigs. Three fat sources with distinctive fatty acid profiles were used; VE levels were 11 (the requirement estimate) and 200 (a high level to assure any responses could be seen) ppm. Increasing VE affected very few FA in tissues. Compared with the control pigs, pigs fed the coconut oil diet had greater content of saturated FA, pigs fed the distiller's corn oil diet had greater content of polyunsaturated FA content, and pigs fed the tallow diet had greater content of monounsaturated FA in tissues. Plasma VE increased with increasing length of feeding but faster in pigs fed the coconut oil and tallow diets compared with the control and distiller's corn oil diets when the 200 ppm VE level was fed; pigs fed the distiller's corn oil diet had the highest plasma VE concentrations when the 11 ppm VE level was fed. In conclusion, dietary VE did not affect FA profile in backfat, belly fat, and liver consistently, while different dietary fat sources affected much of the FA profile in tissues. The higher level of VE, as expected, increased liver and muscle VE concentrations.

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.

The study aimed to assess the effect of vitamin E (VE) supplementation and fat source on growth performance, carcass characteristics, and pork quality of pigs slaughtered at 150 kg. Fat sources included corn starch (no fat added), or 5% tallow, distiller's corn oil (DCO), or coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Increasing dietary VE from 11 to 200 ppm tended to increase the efficiency of conversion of feed to body weight gain for the overall study period. The pigs fed the DCO diet had greater backfat depth at slaughter. Belly (from which bacon is made) firmness was greatest in the pigs fed the CN diet and lowest in those fed the DCO diet. In conclusion, increasing dietary VE levels from 11 to 200 ppm slightly increased growth rate and feed efficiency, and the addition of fat increased feed efficiency and backfat thickness, decreased lean muscle content, and altered belly firmness. While there were some effects of VE supplementation and fat source, 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.

Bioavailability of the calcium salt of dl-methionine hydroxy analog compared with dl-methionine for nitrogen retention and the preference of nursery pigs for diets based on the 2 forms of methionine.

Experiments were conducted to determine the relative bioavailability (RBV) of the calcium salt of the hydroxy analog of dl-methionine (MHA-Ca, 84%) to dl-methionine (dl-Met, 99%) as Met sources fed to pigs. In experiment 1, 42 crossbred barrows (initial BW of 15.0 ± 0.7 kg) were allotted to 7 treatments in an N-balance study. The basal diet (BD) was formulated to contain 15.4% CP and 0.22% Met (70% of requirement). Diets included (1) BD, (2) BD + 0.025% dl-Met, (3) BD + 0.050% dl-Met, (4) BD + 0.075% dl-Met, (5) BD + 0.038% MHA-Ca, (6) BD + 0.077% MHA-Ca, and (7) BD + 0.115% MHA-Ca. An increase in dietary inclusion rates of both Met sources linearly increased (P < 0.01) N retained (g/d) and N retention (% of intake). Using linear slope-ratio regression, the RBV value of MHA-Ca to dl-Met for N retained (g/d) was 63.0% on a product-to-product basis (75.0% on an equimolar basis). In experiment 2, 40 crossbred barrows (initial BW of 15.5 ± 1.5 kg) were allotted to 5 treatments in another N-balance study. The BD was formulated to contain 17.0% CP and 0.22% Met (70% of requirement). Diets included (1) BD, (2) BD + 0.030% dl-Met, (3) BD + 0.060% dl-Met, (4) BD + 0.046% MHA-Ca, and (5) BD + 0.092% MHA-Ca. Increasing levels of dl-Met or MHA-Ca increased N retained (g/d) and N retention (% of intake) linearly (P < 0.001) and quadratically (P < 0.05). Using linear slope-ratio regression, a product-to-product RBV value of MHA-Ca to dl-Met was 68.4% (81.4% on an equimolar basis) for N retained (g/d). In experiment 3, 276 pigs (12 barrow and 11 gilt replicates; initial BW of 7.09 ± 1.1 kg) were used in 3 diet preference studies. Pigs were randomly allotted to 1 of 3 treatment comparisons of feed choice: (1) BD (0.23% Met) or BD + 0.07% dl-Met; (2) BD or BD + 0.0825% MHA-Ca, and (3) BD + 0.07% dl-Met or BD + 0.0825% MHA-Ca. Pigs consumed a higher percentage (55 vs. 45%; P = 0.008) of their total feed intake from the diet supplemented with 0.07% dl-Met in Comparison 1, but a lower percentage (45 vs. 55%; P = 0.003) of their total feed intake from the diet supplemented with 0.0825% MHA-Ca in Comparison 2. There was no diet preference for dl-Met or MHA-Ca in Comparison 3. The observed Met source preference differences occurred in the barrow replicates but not in the gilt replicates. These results demonstrated the mean RBV of MHA-Ca to dl-Met of 65.7% on a product-to-product (wt/wt) basis or 78.2% on an equimolar basis and that a preference for Met sources was observed in barrows but not in gilts.

Effect of Folic Acid Supplementation and Dietary Protein Level on Growth Performance, Serum Chemistry and Immune Response in Weanling Piglets Fed Differing Concentrations of Aflatoxin.

Effects of folic acid and protein levels on growth and serum chemistry in pigs fed aflatoxin were determined in two experiments. Increasing aflatoxin (250 to 800 ppb) decreased (P < 0.05) weight gain and feed intake for both of the 35-day trials. In Experiment 1, increasing aflatoxin (0, 250, 500 ppb), increased linearly (P < 0.05) aspartate aminotransferase (AST), alkaline phosphatase (ALKP) and ɣ-glutamyl transferase (GGT). Folic acid (0, 2.0, 5.0, 12.5 ppm) increased linearly (P < 0.05) serum K, Ca, P, Mg, and AST with the largest effect observed at 12.5 ppm. Folic acid decreased (P < 0.05) blood urea nitrogen (BUN): creatinine and Na:K. In Experiment 2, aflatoxin (800 ppb) increased (P < 0.05) glucose and GGT, and decreased (P < 0.05) Na:K and albumin:globulin. Increasing protein from 15 to 18% elevated BUN: creatinine (P < 0.05), albumin: globulin (P < 0.05), albumin (P < 0.05) and ALKP (P < 0.05). Folic acid (2 ppm) elevated (P < 0.05) BUN, and interacted with both aflatoxin (P < 0.10) and protein (P < 0.05) on BUN. Adding folic acid to aflatoxin contaminated diets improved some measures of clinical chemistry in Experiment 1 but not traditional growth performance measures. The higher protein level reduced the effects of aflatoxicosis on growth.

Effects of group-size-floor space allowance during the nursery phase of production on future litter size and retention of sows through three parities.

We previously reported that reduced floor space allowance caused by increasing the number of gilts per pen decreased growth and affected blood chemistry and immunology. The current objective was to determine effects of nursery group-size-floor space allowance on future litter sizes and retention in the breeding herd through three parities in sows. A 3 × 3 factorial arrangement of treatments was employed with 2,537 gilts classified as large (6.92 ± 0.06 kg), medium (5.60 ± 0.06 kg), or small (4.42 ± 0.06 kg), and placed in nursery pens of 14, 11, or 8 pigs to allow 0.15, 0.19, or 0.27 m2 floor space/pig, respectively. After the nursery and grow-finish periods, 1,453 gilts selected for breeding were relocated to one of 11 sow farms. Total litter size and pigs born alive increased (P < 0.01) with increasing parity and total litter size was 12.94, 13.28, and 13.99 (SE = 0.13) and pigs born alive was 12.21, 12.64, and 13.23 (SE = 0.11) for Parities 1, 2, and 3, respectively. There was a tendency (P = 0.08) for a quadratic relationship of group-size-floor space allowance and total litter size (13.39, 13.54, and 13.27 [SE = 0.13] for gilts allowed 0.15, 0.19, or 0.27 m2 floor space/pig, respectively). A linear effect of size of pig at weaning (P = 0.03) on pigs born dead was detected and was 0.64, 0.75, and 0.75, for small, medium, and large size pigs, respectively. There was no effect of group-size-floor space allowance on the percentages of gilts completing zero (P = 0.36), one (P = 0.35), two (P = 0.32), or three (P = 0.50) parities. In contrast, the percentage of small gilts that failed to complete one parity was greater (P < 0.05) and the percentage completing one parity (P < 0.05) was less than for either large or medium gilts. Abortion rate was greater (P < 0.01) in gilts classified as small (2.51%) or medium (1.36%) at weaning compared with those classified as large (0.20%). Size at weaning did not affect the proportion of gilts completing two (P = 0.88) or three (P = 0.72) parities. Group-size-floor space allowance during the nursery phase of production did not have remarkable effects on future litter sizes or retention in sows. Likewise, size of pig at weaning did not affect litter size and pigs born alive. Compared with larger pigs, however, more pigs classified as small at weaning and entering the breeding herd did not complete a parity and displayed a greater abortion rate.

Effect of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation to lactating sows on growth and indicators of stress in the postweaned pig1,2.

Dietary omega-3 polyunsaturated fatty acids (n-3 PUFA) are precursors for lipid metabolites that reduce inflammation. Two experiments were conducted to test the hypothesis that enriching the sow diet in n-3 PUFA during late gestation and throughout lactation reduces stress and inflammation and promotes growth in weaned pigs. A protected fish oil product (PFO; Gromega) was used to enrich the diet in n-3 PUFA. In the initial experiment, time-bred gilts were fed a gestation and lactation diet supplemented with 0% (control; n = 5), 0.25% (n = 4), 0.5% (n = 4), or 1% (n = 5) PFO from 101 ± 2 d of gestation to day 16 of lactation. Adding 1% PFO to the diet increased the n-3:n-6 PUFA ratio in colostrum and milk compared with controls (P = 0.05). A subsequent experiment was performed to determine whether supplementing the sow diet with 1% PFO improved growth and reduced circulating markers of acute inflammation and stress in the offspring. Plasma was harvested from piglets (16 per treatment group) on day 0 (d of weaning) and days 1 and 3 postweaning. Pigs from the 1% PFO treatment group weighed more (P = 0.03) on day 3 postweaning and had a greater (P ˂ 0.05) n-3:n-6 PUFA ratio in plasma on each day sampled compared with 0% PFO controls. There was an overall treatment effect on plasma total cortisol (P = 0.03) and haptoglobin (P = 0.04), with lesser concentrations in pigs on the 1% PFO diet. Plasma corticosteroid-binding globulin (CBG) concentrations were not different between treatment groups but were less (P ˂ 0.001) on days 1 and 3 when compared with day 0. The resultant free cortisol index [FCI (cortisol/CBG)] was less (P = 0.02) on days 1 and 3 for pigs from the 1% treatment group compared with the controls. An ex vivo lipopolysaccharide (LPS) challenge of whole blood collected on days 0 and 1 was used to determine whether 1% PFO attenuated release of inflammatory cytokines (IL-1ß, IL-6, and TNF-α). Blood from pigs within the 1% PFO treatment group tended (P = 0.098) to have a lesser mean concentration of TNF-α in response to LPS compared with blood from controls. These results suggest that providing a PFO supplement as 1% of the diet to sows beginning in late gestation and during lactation can increase the n-3:n-6 PUFA ratio in their offspring, which may improve growth and reduce the acute physiological stress response in the pigs postweaning.

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.

Disappearance and appearance of an indigestible marker in feces from growing pigs as affected by previous- and current-diet composition.

BACKGROUND: Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal's BW. The objectives of this study were to determine the impact of previous (Phase 1, P1) and current- (Phase 2, P2) diet composition on marker disappearance (Cr) and appearance (Ti) in pigs fed 3 diets differing in NDF content. RESULTS: When pigs were maintained on the 25.1, 72.5, and 125.0 g/kg NDF diets, it took 5.1, 4.1, and 2.5 d, respectively, for Cr levels to decrease below the limit of quantitation; or 4.6, 3.7, or 2.8 d, respectively, for Ti to be maximized. These effects were not, however, independent of the previous diet as indicated by the interaction between P1 and P2 diets on fecal marker concentrations (P < 0.01). When dietary NDF increased from P1 to P2, it took less time for fecal Cr to decrease or fecal Ti to be maximized (an average of 2.5 d), than if NDF decreased from P1 to P2 where it took longer for fecal Cr to decrease or fecal Ti to be maximized (an average of 3.4 d). CONCLUSIONS: Because of the wide range in excretion times reported in the literature and improved laboratory methods for elemental detection, the data suggests that caution must be taken in considering dietary fiber concentrations of the past and currently fed diets so that no previous dietary marker addition remains in the digestive tract or feces such that a small amount of maker is present to confound subsequent experimental results, and that marker concentration have stabilized when these samples are collected.

Summer-Long Grazing of High vs. Low Endophyte (Neotyphodium coenophialum)-Infected Tall Fescue by Growing Beef Steers Results in Distinct Temporal Blood Analyte Response Patterns, with Poor Correlation to Serum Prolactin Levels.

Previously, we reported the effects of fescue toxicosis on developing Angus-cross steer growth, carcass, hepatic mRNA, and protein expression profiles of selected serum proteins, and blood clinical and chemical profiles, after summer-long grazing (85 days) of high endophyte (HE)- vs. low endophyte (LE)-infected fescue pastures. We now report the temporal development of acute, intermediate, and chronic responses of biochemical and clinical blood analytes determined at specified time intervals (period 1, day 0-36; period 2, day 37-58; and period 3, day 59-85). Throughout the trial, the alkaloid concentrations of the HE forage was consistently 19-25 times greater (P ≤ 0.002) than the concentration in the LE forage, and HE vs. LE steers had continuously lower (P ≤ 0.049) serum prolactin (85%), cholesterol (27%), and albumin (5%), but greater red blood cells (7%). The HE steers had decreased (P = 0.003) ADG only during period 1 (-0.05 vs. 0.4 kg/day). For period 1, HE steers had reduced (P ≤ 0.090) numbers of eosinophils (55%) and lymphocytes (18%), serum triglyceride (27%), and an albumin/globulin ratio (9%), but an increased bilirubin concentration (20%). During period 2, serum LDH activities were 18% lower (P = 0.022) for HE vs. LE steers. During period 3, serum levels of ALP (32%), ALT (16%), AST (15%), creatine kinase (35%), glucose (10%), and LDH (23%) were lower (P ≤ 0.040) for HE steers. Correlation analysis of serum prolactin and other blood analytes revealed that triglycerides (P = 0.042) and creatinine (P = 0.021) were moderately correlated (r ≤ 0.433) with HE serum prolactin. In conclusion, three HE-induced blood analyte response patterns were identified: continually altered, initially altered, and subsequently "recovered," or altered only after long-term exposure. Blood analytes affected by length of grazing HE vs. LE forages were either not or poorly correlated with serum prolactin. These data reveal important, temporal, data about how young cattle respond to the challenge of consuming HE pasture.

Effects of phytase supplementation on reproductive performance, apparent total tract digestibility of Ca and P and bone characteristics in gestating and lactating sows / Efectos de la suplementación con fitasa sobre el comportamiento reproductivo, la digestibilidad aparente en tracto total de Ca y P y las características óseas en cerdas gestantes y lactantes / Efeitos da suplementação com fitasse sobre o desempenho reprodutivo, digestibilidade aparente no trato digestivo total de Ca e P e características ósseas em porcas gestantes e lactantes

Background: phytase supplementation to sow diets may improve digestibility of P and Ca and bone integrity of suckling piglets. Objective: two experiments were conducted to investigate the effect of phytase supplementation to gestation and lactation diets on reproductive performance, apparent total tract digestibility (ATTD) of P, Ca, and N in sows and bone characteristics in sows and piglets. Methods: in Experiment 1, a multistate study involving 204 sows was conducted at 3 cooperating research stations. Sows were assigned to 1 of 4 treatments at breeding: 1) negative control [low Ca and available P (aP) diet], 2) Treatment 1 plus 300 FTU of supplemental phytase/kg of diet, 3) Treatment 1 plus 600 FTU of supplemental phytase/kg of diet, and 4) positive control (normal Ca and aP diet). In Experiment 2, a total of 16 sows (Yorkshire × Landrace; average parity, 2.3) were randomly allotted to 1 of 3 treatments based on body weight (BW) and parity at d 34 to 52 of gestation. Treatments were: 1) low Ca and aP diet, 2) low Ca and aP diet with 500 FTU of supplemental phytase/kg of diet, and 3) normal Ca and aP diet. Results: in Experiment 1, the number of total born (p<0.05), live born (p=0.05), litter weight of live born (p<0.01) and weaning pigs (p<0.05) were increased in a quadratic manner by increasing phytase supplementation level up to 300 FTU/kg. There was a linear increase in piglet weaning weight (p<0.05) by increasing supplemental phytase levels. There were no differences in reproductive performance in Experiment 2 (p>0.10). In gestation the ATTD of P was lower for the low Ca and aP without phytase group than the normal Ca and aP (p<0.01) and phytase-supplemented (p<0.05) groups. The ATTD of Ca in the normal Ca and aP group was higher than that in low Ca and aP without phytase group (p<0.05). In lactation, the phytase-supplemented group had higher ATTD of P compared with the other groups (p<0.05) whereas the ATTD of Ca in phytase-supplemented group was higher than that in low Ca and aP without phytase group (p<0.10). When the digestibility data was pooled for both gestation and lactation periods, the ATTD of P in the phytase-supplemented group was the highest among dietary treatments (p<0.05). There were no phytase effects on sow bone ash content at weaning, and piglet bone strength and ash content at birth. However, piglets from the phytase-supplemented sows had higher bone strength (p<0.10) and ash content (p<0.05) at weaning compared with those from non-phytase sows. There were positive correlations at birth between piglet BW and bone strength (p<0.01) and between bone strength and ash content (p<0.001). Additionally, at weaning positive correlations between piglet BW and bone ash content (p<0.05), between piglet BW and bone strength (p<0.001), and between bone strength and ash content (p<0.05) were observed. Conclusion: phytase supplementation from mid-gestation through lactation increased the ATTD of P and Ca both for gestating and lactating sows, improved bone integrity of their progeny, and had potential to increase litter size and performance but did not affect bone characteristics of sows and newborn pigs.

Antecedentes: la adición de fitasa a la dieta de cerdas puede mejorar la digestibilidad del P y Ca, así como la integridad ósea de los cerdos lactantes. Objetivo: se realizaron dos experimentos para investigar el efecto de la suplementación con fitasa en dietas de gestación y lactancia sobre el rendimiento reproductivo, la digestibilidad aparente de tracto total (ATTD) del P, Ca y N en cerdas, y las características óseas de cerdas y lechones. Métodos: el Experimento 1 involucró 204 cerdas evaluadas en 3 centros de investigación norteamericanos. Las cerdas fueron asignadas a 1 de 4 tratamientos al momento del servicio: 1) Control negativo [dieta baja en Ca y P disponible (aP)], 2) Tratamiento 1 más 300 unidades de fitasa (FTU)/kg de dieta, 3) Tratamiento 1 más 600 FTU/kg de dieta, y 4) Control positivo (dieta con contenido normal de Ca y aP). En el Experimento 2, un total de 16 cerdas (Landrace × Yorkshire, de 2,3 partos en promedio) se asignaron al azar a 1 de 3 tratamientos en el d 34 a 52 de gestación, con base en su peso corporal (BW) y número de partos. Los tratamientos fueron: 1) dieta baja en Ca y aP, 2) dieta baja Ca y aP con 500 FTU de fitasa/kg de dieta, y 3) dieta con normal contenido de Ca y aP. Resultados: en el Experimento 1, el número de nacidos totales (p<0,05), nacidos vivos (p=0,05), peso de la camada de los nacidos vivos (p<0,01), y cerdos destetados (p<0.05) se incrementó cuadráticamente con la adición creciente de fitasa hasta el nivel de 300 FTU/kg. Hubo un aumento lineal en el peso al destete de los lechones (p<0,05) al incrementar el nivel de fitasa. En el Experimento 2 no hubo diferencias en rendimiento reproductivo (p>0,10). En gestación, la ATTD del P fue menor en el grupo de bajo Ca y aP sin fitasa que en el de normal Ca y aP (p<0,01) y que en los grupos suplementados con fitasa (p<0,05). La ATTD del Ca en el grupo de normal Ca y aP fue mayor que en el grupo de bajo Ca y aP sin fitasa (p<0,05). En lactancia, el grupo suplementado con fitasa tuvo una mayor ATTD del P en comparación con los otros grupos (p<0,05), mientras que la ATTD del Ca en el grupo suplementado con fitasa fue mayor que en el de bajo Ca y aP sin fitasa (p<0,10). Cuando los datos de digestibilidad se agruparon para los períodos de gestación y lactancia, la ATTD del P en el grupo con fitasa fue la más alta entre los tratamientos dietarios (p<0,05). No hubo efecto de la fitasa en el contenido de cenizas en hueso de las cerdas al destete ni en la resistencia ósea de los lechones o en las cenizas óseas al nacimiento. Sin embargo, los lechones de las cerdas suplementadas con fitasa tuvieron al destete mayor resistencia ósea (p<0,10) y contenido de cenizas (p<0,05) en comparación con los de las cerdas no suplementadas. Hubo correlaciones positivas al nacimiento entre el peso (BW) del lechón y su resistencia ósea (p<0,01), y entre la resistencia ósea y su contenido de cenizas (p<0,001). Además, se observaron correlaciones positivas al destete entre el BW del lechón y su contenido de ceniza en hueso (p<0,05), entre el BW del lechón y su resistencia ósea (p<0,001), y entre la resistencia y el contenido de cenizas óseas (p<0,05). Conclusión: la suplementación con fitasa desde la mitad de la gestación y durante la lactancia aumentó la ATTD del P y Ca, en cerdas tanto gestantes como lactantes, mejoró la integridad ósea de la progenie, y mostró potencial para aumentar el tamaño y rendimiento de la camada, pero no afectó las características óseas de las cerdas ni de los recién nacidos.

Antecedentes: a adição de fitasse na dieta de porcas pode melhorar a digestibilidade do P e Ca, assim como a integridade óssea dos leitões. Objetivo: realizaram-se dois pesquisas para conferir o efeito da suplementação da fitasse em dietas para os períodos de gestação e lactação sobre o desempenho reprodutivo, a digestibilidade aparente no trato digestivo total (ATTD) de P, Ca e N em porcas, e as características ósseas de porcas e leitões. Métodos: o experimento 1 envolveu 204 porcas avaliadas em 3 centros de pesquisa dos Estados Unidos. As porcas foram designadas para um de quatro tratamentos no momento do serviço: 1) controle negativo [dieta baixa em Ca e P disponível (aP)], 2) Tratamento 1 mais de 300 unidades de fitasse (FTU) / kg de ração, 3) Tratamento 2, mais de 600 FTU / kg de ração, e 4) controle positivo (dieta com teor normal de Ca e aP). No Experimento 2, um total de 16 matrizes suínas (Landrace × Yorkshire, de 2,3 nascimentos em média) foram randomizados para 1 de 3 tratamentos nos dias 34-52 de gestação, com base no peso corporal (PC) e número de partos. Os tratamentos foram: 1) dieta pobre em Ca e Pd, 2) dieta pobre em Ca e aP com 500 FTU de fitasse / kg de ração, e 3) dieta com teor normal de Ca e aP. Resultados: no Experimento 1, o número de nascimentos totais (p<0,05), nascidos vivos (p=0,05), peso da leitegada de nascidos vivos (p<0,01) e leitões desmamados (p<0,05) aumentou quadraticamente com a adição crescente de fitasse no nível de 300 FTU / kg. Houve um aumento linear do peso ao desmame de leitões (p<0,05) com os níveis crescentes de fitasse. No experimento 2, não houve diferença no desempenho reprodutivo (p>0,10). Na gravidez, o ATTD de P foi menor no grupo de baixo Ca e aP sem fitasse do que no grupo Ca normal e aP (p<0,01) e nos grupos de fitasse suplementado (p<0,05). O ATTD de Ca no grupo normal de Ca e aP foi maior do que no grupo de baixo Ca e aP sem fitasse (p<0,05). Na lactação, no grupo suplementado com fitasse apresentou um ATTD de P maior em relação aos outros grupos (p<0,05), enquanto o ATTD de Ca do grupo suplementado com fitasse foi maior do que no grupo baixo de Ca e Pd e sem fitasse (p<0,10). Quando os dados de digestibilidade foram agrupados para os períodos de gestação e lactação, a ATTD de P no grupo com fitasse foi maior entre os tratamentos dietéticos (p<0,05). Não houve efeito da fitasse no teor de cinzas de osso de porcas ao desmame ou a força dos ossos ou cinzas ósseas dos leitões ao nascimento. No entanto, os leitões de porcas suplementadas com fitasse tiveram uma maior resistência óssea ao desmame (p<0,10), e cinzas (p<0,05) em comparação com as porcas não suplementadas. Houve correlação positiva entre peso (BW) ao nascimento do leitão e a resistência óssea (p<0,01) e entre a força dos ossos e cinzas (p<0,001). Além disso, foi observada uma correlação positiva entre o desmame dos leitões BW e teor de cinzas ósseas (p<0,05), entre BW dos leitões e a resistência óssea (p<0,001), e entre a resistência óssea e os conteúdos e cinza nos ossos (p<0,05). Conclusão: a suplementação com fitasse na etapa media da gestação e durante a lactação aumentou a ATTD de P e Ca, tanto em porcas gestantes quanto lactantes, melhorou muito a integridade óssea da progênie, e mostrou potencial para aumentar o tamanho e desempenho da leitegada, mas não afetou as características ósseas das porcas nem dos leitões recém nascidos.

Dietary supplementation of boron differentially alters expression of borate transporter (NaBCl) mRNA by jejunum and kidney of growing pigs.

Inorganic boron (B), in the form of various borates, is readily absorbed across gastrointestinal epithelia. Although there is no stated B requirement, dietary B supplementation is thought to positively affect animal growth and metabolism, including promotion of bone strength and cell proliferation. Because of effective homeostatic control of plasma B levels, primarly by renal excretion, B toxicity in animals and humans is rare. The mechanisms responsible for improved animal performance and borate homeostasis are incompletely understood. Although a Na+-coupled borate transporter (NaBC1) has been identified, the effect of dietary B supplementation on expression of NaBCl has not been evaluated. An experiment was conducted with growing pigs to determine if NaBC1 mRNA was expressed by small intestinal epithelia and kidney of growing barrows and whether dietary B (as borate) supplementation would affect expression of NaBC1 mRNA. A concomitant objective was to test the hypothesis that B supplementation of a phosphorus (P)-deficient diet would improve calcium, phosphorus, or nitrogen retention. Twenty-four crossbred growing barrows (body weight=74.0±9.8 kg) were selected and used in a randomized complete block design experiment with a total of eight blocks and three B supplementation treatments (n=8/treatment). A typical corn-soybean meal basal diet (calculated to contain 41 mg intrinsic B/kg) was formulated to meet or exceed nutrient requirements, except for P, and fed to all pigs for 12 days. The basal diet plus 0, 50, or 100 mg/kg of B (prilled sodium borate pentahydrate, Na2B4O7·5H2O) was then fed for 18 more days. Feces and urine were collected during days 6 to 16 of the B supplementation, and pigs were killed for collection of jejunal and ileal epithelia and kidney tissue. Real-time reverse transcription-PCR analysis revealed that NaBC1 mRNA was expressed by these tissues, a novel finding for jejunal and ileal epithelia. Boron supplementation increased jejunal, but decreased, renal NaBC1 mRNA expression, relative to the 0 mg/kg treatment. The finding that NaBC1 mRNA is regulatable by dietary B is novel. That B supplementation evoked opposite effects on jejunal and kidney NaBC1 mRNA expression indicates that transcriptional regulation of NaBC1 expression may constitute a part of the homeostatic control of B metabolism. In contrast to its effect on NaBC1 mRNA expression, B supplementation did not affect total tract digestibility or retention of phosphorus, calcium, or nitrogen.

Phosphorus utilization in growing pigs fed a phosphorus deficient diet supplemented with a rice bran product and amended with phytase / Utilización de fosforo en cerdos de ceba alimentados con una dieta baja en fosforo, suplementada con salvado de arroz y fitasa / Utilização do fósforo em suínos alimentados com uma dieta baixa em fósforo, suplementada com farelo de arroz e fitase

Rice bran is not only a source of energy for pigs, it also contains significant amounts of phosphorus (P). However, about 75% of this P is not digested by the pig, unless phytase is added to the diet. Once excreted, P may end up contaminating water bodies and thus causing eutrophication. The objectives of this study were to determine the digestibility of P and other nutrients in a diet supplemented with increasing levels of rice bran (0, 7.5, 15, and 30%), and to evaluate the effects of phytase inclusion on the nutrient digestibility of rice bran. Pigs (n= 24, 87.5 ± 2.51kg) were confined in individual metabolic crates to determine total tract apparent digestibility and retention of nutrients. The digestibility coefficients found for dry matter, energy, fat, N, and P in the rice bran product used were: 72, 79, 84, 74, and 15%, respectively. Phytase supplementation increased P digestibility (p<0.01) but it did not increase N digestibility (p>0.1); the increase in fecal P excretion that occurred when rice bran was added to the diet was reduced by 26% with phytase supplementation.

El salvado de arroz no sólo es una interesante fuente de energía para cerdos, sino que contiene bastante fósforo (P). Sin embargo, cerca del 75% de ese P no es utilizable por los cerdos, a menos que se adicione alguna fitasa a la dieta de estos animales. Al no utilizarse, dicho P es excretado, pudiendo contaminar fuentes de agua y generando eutroficación del recurso hídrico. El objetivo del presente trabajo fue establecer la digestibilidad del P y otros nutrientes en una dieta suplementada con niveles crecientes de salvado de arroz (0, 7.5, 15, y 30%), así como evaluar el efecto de la inclusión de fitasa en la digestibilidad de nutrientes del salvado. Para esto se utilizaron 24 cerdos (87.5 ± 2.51kg), confinados en jaulas metabólicas individuales, a los que se les calculó digestibilidad total aparente y retención de nutrientes por el método de Colección Total. Los coeficientes de digestibilidad encontrados fueron: 72, 79, 84, 74, y 15% para materia seca, energía, grasa, N y P, respectivamente. La suplementación con fitasa incrementó la digestibilidad del P (p<0.01), pero no incrementó la digestibilidad del N (p>0.1). El incremento observado en la excreción fecal de P al adicionar salvado de arroz a la dieta fue disminuido en 26% con la adición de fitasa.

O farelo de arroz não é apenas uma fonte de energia interessante para os suínos, ele contém suficiente fósforo (P). No entanto, perto do 75% de P não é usado pelos suínos, a menos que adicione-se alguma fitase na dieta desses animais. Quando não for utilizado, o P é excretado e podem contaminar fontes de água e eutrofização dos recursos hídricos. O objectivo deste estudo foi determinar a digestibilidade do P e outros nutrientes de uma dieta suplementada com níveis crescentes de farelo de arroz (0, 7.5, 15 e 30%), e para avaliar o efeito da fitase sobre a digestibilidade de nutrientes de farelo. Para isso, 24 animais (87.5 ± 2.51 kg), foram confinados em gaiolas metabólicas individuais. Foi calculada a digestibilidade total e retenção de nutrientes pelo método de colheita total. Os coeficientes de digestibilidade encontrados foram: 72, 79, 84, 74 e 15% de matéria seca, energia, gordura, N e P, respectivamente. A suplementação de fitase aumentou o P digestível (p<0.01), porém, aumentou a digestibilidade do N (p>0.1). O aumento observado na excreção fecal de P pela adição de farelo de arroz à dieta foi reduzida em 26% com a adição de fitase.

The effects of dietary chromium(III) picolinate on growth performance, vital signs, and blood measurements of pigs during immune stress.

This experiment used 24 pigs (26.0 kg) to investigate the effects of dietary chromium (Cr) on pigs challenged with lipopolysaccharide (LPS). Following 35 days of diet exposure, the immune stress treatments were: (1) phosphate-buffered saline (PBS) injection and no Cr, (2) LPS injection and no Cr, (3) LPS injection and Cr 1,000 ppb, and (4) LPS injection and Cr 2,000 ppb. At 0 h, PBS or LPS was injected intraperitoneally in each pig. During the first 12 h post-injection, pigs challenged with LPS lost 951 g, while the PBS group gained 170 g (p < 0.001). Compared with the PBS group, LPS-challenged pigs consumed less feed (p < 0.01) during the first 24 h. The LPS group had higher rectal temperature at 2 and 4 h and higher respiratory rate at 1.3 and 8.5 h than the PBS group (p < 0.05). Plasma collected at 3 h had higher cortisol (p < 0.001) and lower glucose (p < 0.05) concentrations in the LPS group than the PBS group. However, supplemental Cr did not affect the response variables. Overall, the LPS challenge affects growth performance, vital signs, and plasma variables, but dietary Cr is unable to moderate stress-related effects associated with an LPS challenge.