Bioplex Nutrition Articles & Resources

Key Words: Electrolytes, Growth, Pigs

406 Comparisons of inorganic and organic trace mineral supplementation for grow-finish swine. J. L. Burkett*1, K. J. Stalder1, C. R. Schwab1, T. J. Baas1, D. W. Newcom1, J. L. Pierce2, W. J. Powers1, and J. W, Mabry1, 1Dept. of Animal Science, Iowa State University, Ames, 2Alltech Inc., Nichoiasville, KY.

A study was conducted to investigate the effect of inorganic and organic mineral supplementation on the growth and ultrasonically measured carcass characteristics of swine. In each of the two replications, 264 pigs were used in a completely randomized design with four dietary treatments and 10 - 12 pigs per pen (n - 24) throughout the grow-finish period. A commercial line of barrows and gilts were penned by sex, and randomly assigned to one of the four treatments at approximately 27 kg. Treatment 1 (control) contained a common trace mineral supplement (Kent Feeds, Muscatine, IA), while treatments 2, 3, and 4 contained Alltech's Bioplex products at 100%, 75%, and 50% of the common trace mineral supplemental levels, respectively. Individual tenth rib backfat (BF) and loin muscle area (LMA) measurements were evaluated ultrasonically on all pigs prior to marketing (118 kg). Average daily gain and average daily lean growth on test (LGOT) were calculated from the data collected on individuals. Pen feed intake was calculated by feed weigh-back to determine ADFI, feed efficiency (FE), and efficiency of lean gain (LE). Pen was the experimental unit of measurement in this study. Data from this study were analyzed using a mixed linear model with fixed effects of replication, treatment, and sex and the interaction of sex by treatment. Pen nested within treatment was included as a random effect for the evaluation. Off test weight was included as a covariate for the analyses of BF and LMA. On test weight was included as a covariate in the analyses of ADG, LGOT, ADFI, FE, and LE. Replication and sex effects were significant sources of variation for BF, LMA, ADG, LGOT, and ADFI. Pigs fed the control diet consumed less (P ) among the treatment means for BF, LMA, ADG, LGOT, and LE.

Key Words: Pigs, Mineral Supplementation, Ultrasound Measurements

407 The effects of high phytase levels on nutrient digestibility, growth performance and bone characteristics in growing pigs. M. J. Azain*1 and M. R. Bedford2, 1 University of Georgia, Athens, 2Zymetrics, Golden Valley, MN.

Phytase is typically supplemented at less than 1000 U/kg diet. The objective of this study was to look at the effects of higher levels of phytase supplementation in the growing pig. A total of 144 pigs (initial wt = 13 kg) were randomly assigned to one of six dietary treatments with 3 barrows or 3 gilts per pen and a total of 48 pens in 2 trials. A corn-soy diet (20% CP, % lysine) was used. Diet 1 was the positive control and contained % Ca and calculated total and available P of and %, respectively. Diets 2-6 had less dicalcium phosphate added and contained % Ca and and % total and available P. Diet 2 was the negative control and diets 3-6 were supplemented with 100-12,500 U/kg feed of a novel E. coli Phytase expressed in Pichia pastoris. Diets were fed for 28 d. Apparent nutrient digestibility was determined UKing chromic oxide as a marker during the last week of the trial. Pigs were euthanized and metatarsal bone isolated for determination of bone strength and mineral content. Pigs fed the P deficient diet had reduced growth and efficiency as well as decreased bone weight and strength. Phytase addition improved growth rate and bone parameters. Ca and P digestibility were improved with phytase, but there was no significant effect on protein or energy digestibility. Bone Ca and P content were not affected by dietary treatment. However, bone Mg was decreased and K increased on the P deficient diet. Both were normalized with the addition of phytase to the diet. Pigs fed diets with 12,500 U Phytase/kg had growth rates, nutrient digestibilities and bone characteristics that were superior to the pigs fed the positive control diet. This effect may be accounted for by the removal of the anti-nutritional effects of phytate.

Key Words: Swine, Phytase, Bone Ash

408 Shifting the pH profile of Aspergillus niger PhyA phytase improves its efficacy in pig diets. S. U. Rice, T. G. Ko, T. W. Kim, K. R. Roneker, and X. G. Lei*, Cornell University, Ithaca, NY.

Aspergillus niger PhyA phytase is widely used in swine diets, but its pH optimum () is too high for an effective hydrolysis of phytate-P under the acidic condition in the pig stomach. Using site-directed mutagenesis, we have developed two mutants (TK10 and TK228) with lower pH optima than the wild-type (WT) of PhyA. The objective of this experiment was to compare the effectiveness of TK10 and TK224 with that of WT in improving dietary phytate-P availability to pigs. A total of 24 weanling pigs ( ± kg BW) were divided into three groups (n = 8), and fed a low-P, corn-soybean meal basal diet supplemented with the WT, TK10, or TK228 phytases at 250 units/kg of feed for five weeks. Growth performance, plasma inorganic P concentration, and plasma alkaline phosphatase activity of individual pigs were recorded or measured weekly. The overall daily gain of pigs fed the TK228 mutant phytase was 13% higher (509 vs 451 g, P

Key Words: Phytase, Pigs, Phosphorus

409 Phosphorus excretion of pigs fed conventional or low-phytate corn-soybean meal diets without or with phytase. E. G. Xavier, L. A. Pettey, G. L. Cromwell*, and M. D. Lindemann, University of Kentucky, Lexington.

Two 5-d balance experiments were conducted to assess diets containing normal (N) corn and N soybean meal (SBM) or low-phytate (LP) corn and LP, low-oligosaccharide SBM without or with phytase (Natuphos® , BASF; 750 units/kg) on total and soluble P excretion in pigs. The LP-corn and LP-SBM were provided by Pioneer Hi-Bred International. The N-corn, LP-corn, N-SBM and LP-SBM contained , , , and % total P and , , , and % non-phytate P with estimated P bioavailabilities of 20, 75, 25, and 50%, respectively. Twelve pigs (52 kg) in metabolism crates were fed four diets (% lysine)

fluring two periods. Feeding level WRH equalized within roplicationH and averaged 96% of ad libitum intake. Diets were (1) N-corn + N-SBM, % P; (2) N-corn + N-SBM + phytase, % P; (3) LP-corn + LP-SBM, % P; and (4) LP-corn + LP-SBM + phytase, % P. Diet 4 contained no added inorganic P. Ca was reduced from % in Diets 1 and 3 to % in Diets 2 and 4. All diets had the same levels of nonphytate P (%) and bioavailable P (%), assuming that phytase released one-third of the unavailable P. Daily feed and P intake averaged , , , kg/d and , , , g/d for Diets 1 to 4, respectively. Apparent P digestibility was increased by feeding the LP- vs N-diets and by phytase addition (37, 56, 66, 78%; P ) by diet (, , , g/d).

Key Words: Pigs, Phosphorus, Phytase

410 Estimation of Ca and P retention in bone, fatfree soft tissue, and other whole body and carcass components in growing-finishing pigs from 18 to 109 kg. L. A. Pettey*, G. L Cromwell, and M. D. Lindemann, University of Kentucky, Lexington.

The distribution of Ca and P in carcass bone, carcass fat-free soft tissue (FFST), and viscera (empty)-head-blood-skin (VHBS) was determined in 50 pigs from 18 to 109 kg BW to develop equations describing the retention rates of Ca and P. Ca and P in hair and hooves was inconsequential. Data were combined from two studies in which pigs were killed at 18, 27, 36, 45, 54, 73, 91, and 109 kg. Pigs were fed fortified corn-soy diets (four phases) that exceeded NRC standards for lysine, Ca, and P by %. Carcasses were split with the right half physically separated into soft tissue, bone, and skin. Chemical analysis was conducted on each body tissue. Carcass bone represented , , , , , , , and % of BW for the eight weight groups, respectively. Bone Ca represented % of the Ca in the carcass and was constant from 18 to 109 kg BW. Carcass P contributed by bone was constant from 18 to 54 kg (%), but increased linearly (P

Key Words: Pigs, Bone, Phosphorus

411 Endogenous excretion of phosphorus and calcium in growing pigs fed two varieties of soybean meal. R. N. Dilger* and O. Adeola, Purdue University, West Lafayette, IN.

Using the regression approach, whole body endogenous excretion of phosphorus and calcium were measured in growing pigs fed diets containing conventional or high available phosphorus (HAP) soybean meals (SBM) as the primary phosphorus and calcium source. Semipurified cornstarch-based diets contained four graded levels of each soybean meal; thereby creating a linear dietary intake of phosphorus (, , and g/kg DM) and calcium (, , and g/kg DM). Chromic oxide ( g/kg diet, as-fed) was used as an indigestible index and pigs were fed at a rate of *BW^sup ^ kg according to individual weekly BW. Sixteen barrows (average initial BW of kg) were fitted with simple T-cannula at the distal ileum and fed the diets according to a replicated 8 X 8 Latin square design. Experimental periods were 7 d in length with 5 d diet acclimation, sampling of feces on d 5 and 12-h collection of ileal digesta on each of d 6 and 7. Apparent pre-cecal phosphorus and calcium digestibilities exhibited a linear relationship to dietary mineral intake for conventional (P ). Conversely, apparent total tract phosphorus and calcium digestibilities increased linearly to dietary mineral intake for HAP (P ). Endogenous outputs of phosphorus in ileal digesta were different between SBM sources (P ; vs. g/kg DMI for conventional and HAP SBM, respectively). True pre-cecal and total tract digestibilities of phosphorus and calcium were higher for HAP SBM compared with conventional SBM (P

Key Words: Endogenous, Minerals, Pigs

412 A novel procedure for measuring endogenous phosphorus losses and true phosphorus digestibility by growing pigs. G. I. Petersen* and H. H. Stein, South Dakota State University, Brookings.

A novel procedure was developed to estimate endogenous losses of phosphorus by growing pigs. A P-free diet was formulated using mainly cornstarch, dextrose, gelatin, and crystalline AA. In Exp. 1, two P-free diets were formulated using gelatin of either porcine or bovine origin. The apparent (AID) and standardized (SID) ileal digestibility coefficients of AA in these two diets were compared to the AID and SID in soybean meal (SBM). Results of this experiment showed that there were no differences in AID or SID for any of the indispensable AA except for trp between the three feed ingredients when fed to growing pigs. In Exp. 2, a P-free diet based on gelatin of porcine origin was used to measure the apparent (ATTD) and true (TTTD) total tract digestibility of three sources of inorganic phosphorus. In addition to the P-free diet, three other diets were formulated based on the P-diet, but each of these diets were supplemented with either monosodium phosphate (MSP), purified monocalcium phosphate (MCP) or dicalcium phosphate (DCP). The inorganic phosphate sources were added to the P-free diet to reach a total P-content in the diets of %. Each of the four diets was fed to 7 pigs for 12 d. Fecal material was collected for five d using the marker to marker procedure. Results of the experiment showed that the ATTD in DCP was lower (P ≤ ) than in MCP ( vs. %), while the ATTD in MCP (%) was similar to the other two sources. The endogenous losses of P were calculated based on the P-concentration in the fecal samples from pigs fed the P-free diet and averaged g P per kg DMI. By correcting the ATTD for the endogenous losses, the TTTD were calculated. For DCP, MCP, and MSP, the TTTD was , , and %, respectively. The value for MSP was higher (P ≤ ) than the value for DOP, while the TTTD for MCP was not different from the other two sources. The two experiments showed that the P-free diet provides a way of estimating endogenous losses of P in pigs and can be used to calculate ATTD and TTTD in feed phosphates.

Key Words: Endogenous Loss of P, P-Free Diet, True Digestibility of P

413 Evaluation of the bioavailability of phosphorus in distillers dried grains with solubles (DDGS) when fed to pigs. R. W. Fent*1, T. S. Torrance2, B. W. Ratliff1, S, X. Fu1, G. L. Allee1, D. M. Webel2, and J. D. Spencer2, 1 University of Missouri, Columbia, 2 United Feeds, Inc., Sheridan, IN.

A slope ratio assay was conducted to estimate the bioavailability of phosphorus (P) in distillers dried grains with solubles (DDGS). Seventy-two barrows (initial wt = kg) were individually penned and allotted by weight to one of nine dietary treatments in a randomized complete block design. All diets were cornstarch-soybean meal based. Treatments 1-7 comprised the slope ratio assay consisting of a basal diet (% P, % TID Lys) and diets containing , , and % additional P from either monosodium phosphate (MSP) or DDGS. The two additional diets consisted of the % P DDGS + 500 FTU/kg phytase (Optiphos#8482; Phytex, LLC) and the basal diet + 500 FTU/kg to assess the possible further liberation of phosphorus. Pigs were allowed ad libitum access to feed and water. After a 28-d feeding period, all pigs were weighed, sacrificed, and right fibulas collected for analysis of bone breaking load and bone ash content. The standard curve (MSP) and the DDGS titration both resulted in linear improvements (P

Key Words: Distiller's Dried Grain, Phosphorus, Pigs