T D Crenshaw | University of Wisconsin-Madison (original) (raw)

Papers by T D Crenshaw

Research paper thumbnail of the effect on sow and litter performance for three successive parities The addition of ground wheat straw as a fiber source in the gestation diet of sows and

Research paper thumbnail of Additions of Lysine, Tryptophan, Methionine and Isoleucine to All-Corn Diets for Finishing Swine

Research paper thumbnail of Combined Water and Fat Suppressed Proton Projection MRI (WASPI) and Micro CT Measurement of Bone Mineralization

H. Cao, J. Ackerman, T. D. Crenshaw, P. Dunning, M. Glimcher, and Y. Wu Department of Orthopaedic... more H. Cao, J. Ackerman, T. D. Crenshaw, P. Dunning, M. Glimcher, and Y. Wu Department of Orthopaedic Surgery, Children's Hospital, Boston, MA, United States, Harvard Medical School, Boston, MA, United States, Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, Department of Animal Sciences, University of Wisconsin, Madison, WI, United States, Department of Radiology, Children's Hospital, Boston, MA, United States

Research paper thumbnail of In Vitro Fermentation of Swine Ileal Digesta Containing Oat Bran Dietary Fiber by Rat Cecal Inocula Adapted to the Test Fiber Increases Propionate Production But Fermentation of Wheat Bran Ileal Digesta Does Not Produce More Butyrate

The Journal of Nutrition, 2000

This experiment evaluated three hypotheses: i) production of propionate is increased during ferme... more This experiment evaluated three hypotheses: i) production of propionate is increased during fermentation of substrate containing oat bran (OB) 6 ; ii) production of butyrate is increased during fermentation of substrate containing wheat bran (WB) and iii) results of in vitro fermentations using physiological substrates and inocula agree with in vivo data. Ileal digesta collected from swine fed OB and WB were the substrates. Digesta was fermented for 0-96 h in an anaerobic in vitro system using inocula prepared from ceca of rats fed the same fiber sources. Carbohydrate and short-chain fatty acid (SCFA) contents in the fermentations were measured by gas chromatography. Fermentation of WB digesta did not produce more n-butyrate (P Ͼ 0.05) and was significantly slower (P Ͻ 0.05) than fermentation of OB digesta. OB digesta fermentation produced a significantly greater (P Ͻ 0.05) molar proportion of SCFA as propionate. Bacterial mass increased more and was maintained longer during fermentation of OB digesta than the WB digesta. Our results indicate that dilution of undigested WB fiber and not n-butyrate production is one mechanism by which WB may protect colonic mucosa; propionate production is increased during fermentation of ␤-glucan in OB; and an in vitro system using physiological sources of inoculum and substrate containing WB and OB yields results that agree with in vivo findings in humans and rats.

Research paper thumbnail of Postnatal Age and the Metabolism of Medium- and Long-Chain Fatty Acids by Isolated Hepatocytes from Small-for-Gestational-Age and Appropriate-for-Gestational-Age Piglets

The Journal of Nutrition, 1991

ABSTRACT Hepatocytes were isolated from full-term small-for-gestational-age (SGA) and appropriate... more ABSTRACT Hepatocytes were isolated from full-term small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) piglets at 6 or 48 h postpartum and incubated with 1 mmol/L [1-14C]-octanoate (8:0), -nonanoate (9:0) or -oleate (18:1). The cells oxidized [nmol 1-C/(h.10(6) cells)] 9:0 to carbon dioxide (12.5) and acid soluble products (28.9) faster than 8:0 (10.9, 20.6, respectively), and both were oxidized faster than 18:1 (3.9, 9.9) regardless of the piglet age or weight. Oleate accumulated in lipid products eightfold faster than did 8:0 and 9:0. No differences between cells from SGA and AGA piglets were detected. Recovery of 1-C in CO2 was 48% higher in incubations with cells from 48-h-old than from 6-h-old piglets. This increase was attributable to a 70% higher O2 consumption by 48-h-old cells. Theoretical O2 consumption rates were computed from the fatty acid flux data and compared with measured O2 consumption. Hepatocytes from SGA and AGA piglets were equally capable of satisfying greater than 75% of their energy needs from fatty acid oxidation. The O2 consumption attributable to 9:0 metabolism was 30% higher than observed for 8:0 and 18:1. All fatty acids apparently spared endogenous fuels to a greater degree in 6-h-old than in 48-h-old piglets.

Research paper thumbnail of Chapter 9 Use Of A Four Parameter Logistic Equation And Parameter Sharing To Evaluate Animal Responses To Graded Levels Of Nitrogen Or Amino Acids

Advances in Food and Nutrition Research, 1996

ABSTRACT This chapter discusses the use of a four parameter logistic equation and parameter shari... more ABSTRACT This chapter discusses the use of a four parameter logistic equation and parameter sharing to evaluate animal responses to graded levels of nitrogen or amino acids. The chapter provides the diminishing returns and dose-response relationships, the diminishing returns and protein quality, and the response of rats to each indispensable amino acid. A desirable feature of the statistical approach to define a linear-plateau relationship is that a single nutrient level is defined as the requirement to maximize growth. The change in limiting amino acid also explains the change in relative values of proteins from maintenance to maximum gain. Amino acids used with different efficiencies, can evoke a different diminishing returns response when fed to rats. A series of crystalline amino acid diets were used to examine the response of rats to each indispensable amino acid when limiting. Because of the curvilinear nature of the dose-response relationship, amino acid requirements should be estimated taking into account the decreasing efficiency associated with diminishing returns.

Research paper thumbnail of PSXVI-30 Supplemental Vitamin D3 for mediation of immune challenges in nursery pigs and subsequent growth responses

Journal of Animal Science, 2018

Research paper thumbnail of PSII-17 Phosphorus Release Values in Growing Pigs Fed Increments of Optiphos Plus Phytase in Pelleted Diets

Journal of Animal Science, 2021

The efficacy of phytase (Pase) from OptiPhos Plus G (Huvepharma, Peachtree City, GA) was compared... more The efficacy of phytase (Pase) from OptiPhos Plus G (Huvepharma, Peachtree City, GA) was compared to inorganic phosphorus (iP) supplements to assess phosphorus equivalency. In 6 replicate 28-d trials, 288 crossbred F2 (Duroc X LR X LW) pigs (20.0 kg, 6 pigs/pen, 48 pens) were randomly assigned to 1 of 8 diets. Pig sex was balanced within pens. Basal corn-soybean meal diets, formulated to exceed nutrient requirements except for Ca and P, supplied 1.30% lysine from the same amounts of all ingredients. Sand was used to balance variable amounts of monocalcium phosphate and limestone. Diets supplied either 0.061, 0.156, or 0.241% iP from monocalcium phosphate or increments of 250, 500, 750, 1,000 and 1,500 FTU/kg from Pase. All diets were pelleted (160°F, 2.5 tons/hr). The modified pellet durability index averaged 92.8% and 88.7% for all diets in each of 2 mixes. Non-linear growth responses to increments of iP and Pase were detected (P < 0.05). Using nonlinear regression models, maxim...

Research paper thumbnail of Nutritional composition, gross energy concentration, and in vitro digestibility of dry matter in 46 sources of bakery meals

Journal of Animal Science, 2018

Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies ... more Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies depending on where in the United States the meal is produced due to different raw materials being used in the production of the meals. Forty-six samples of bakery meal were collected from feed mills located in the swine producing states in the United States. Based on the state where samples were collected, they were grouped into 5 regions: 1) AL, DE, GA, NC, PA, and VA (10 samples); 2) CO, MO, OK, and TX (10 samples); 3) IN, KY, OH, and TN (8 samples); 4) IA (11 samples); and 5) MN (7 samples). All samples were analyzed for proximate components, GE, AA, carbohydrates, and minerals, and IVDMD and in vitro energy digestibility (IVGED) were also determined. Results indicated that the average concentration of DM was (91.84 ± 1.29%) and there was no difference among regions. The concentration of ash in bakery meal from MN was greater (P < 0.05) than in meals from other regions, but for all other proximate components, no differences among sources were observed. The average concentration (DM basis) of CP (12.20 ± 2.16%), acid hydrolyzed ether extract (AEE, 9.38 ± 1.95%), starch (44.61 ± 5.47%), and NDF (13.77 ± 4.23%) indicated that bakery meal

Research paper thumbnail of Nonruminant Nutrition: Enzymes

A total of 180, 18-d crossbred pigs (GAP English Belle × Duroc) with BW of 7.0 ± 1.1 kg were rand... more A total of 180, 18-d crossbred pigs (GAP English Belle × Duroc) with BW of 7.0 ± 1.1 kg were randomly allotted to 6 treatments with 5 replicate pens/treatment for 3 phases with 11, 11 and 12 d in each feeding phase, respectively. Six corn-soybean meal mash diets were formulated: a positive control (PC) diet (0.32% available P (aP); met NRC, 1998 recommendations), a negative control (NC) diet with approximately 10% reduction of aP (0.28% aP), NC + 200 FTU/kg Quantum (QP: E. coli phytase expressed in Pichia pastoris), NC + 500 FTU/kg QP, NC + 1,250 FTU/kg QP, and NC + 500 FTU/kg Natuphos (NP; fungal phytase expressed in Aspergillus niger). On d 42, 9 pigs from each treatment were randomly selected and euthanized for metatarsal collection to measure breaking strength and to determine ash and P content. Ash and P content of the metatarsal bone was not different among the dietary treatments. However, sex influenced (P < 0.01) metatarsal ash, and P content. In general, the average ash ...

Research paper thumbnail of Bone mechanical properties after exercise training in young and old rats

Journal of Applied Physiology, 1990

The effects of a 10-wk training regimen on the mechanical properties of the femur and humerus wer... more The effects of a 10-wk training regimen on the mechanical properties of the femur and humerus were evaluated in 2.5- and 25-mo-old Fischer 344 female rats. The rats trained on a rodent treadmill 5 days/wk for 10 wk. Duration, grade, and speed increased until the rats maintained 1 h/day at 15% grade and either 15 m/min (old rats) or 36 m/min (young rats). Excised bones were mechanically tested with a 3-point flexure test for mechanical properties of force, stress, and strain. Fat-free dry weight (FFW) and moment of inertia were also obtained. With aging, similar increases were observed in both the femur and humerus for FFW, moment of inertia, and force. Ultimate stress was reduced in the senescent femur while strain was elevated; a similar but nonsignificant trend was observed in the humerus. Irrespective of age, training increased FFW in the femur and, to a lesser degree, in the humerus. Breaking force was elevated for both bones after training. In young and old bones, the training-...

Research paper thumbnail of Bone Strength as a Trait for Assessing Mineralization in Swine: a Critical Review of Techniques Involved

Journal of Animal Science, 1981

Research paper thumbnail of Evaluating the effects of supplemental B vitamins in practical swine diets during the starter and grower-finisher periods A regional study

Journal of Animal Science, 2007

Two experiments were conducted to evaluate dietary fortification levels of a B vitamin premix for... more Two experiments were conducted to evaluate dietary fortification levels of a B vitamin premix for starter and grower-finisher pigs on subsequent performance responses. The objective was to determine whether the modern pig requires higher dietary levels of B vitamins than estimated by the NRC (1998). Both experiments added fat-soluble vitamins at the requirement levels (NRC, 1998) in all diets, whereas the B vitamins were added at 0, 100, 200, or 400% of the total NRC (1998) requirement levels for the starter and grower pig. ndigenous vitamin contributions from the feed grains were not included in the estimates. Each station used the same vitamin premixes but incorporated its own grain sources in the diets. The first experiment was conducted across 7 stations (

Research paper thumbnail of 95 Growth Performance, Bone Mineralization, and Nutrient Digestibility of Nursery-grower Pigs Fed Phytase-supplemented Calcium and Phosphorus-deficient Diets

Journal of Animal Science, 2021

A 36-d experiment evaluated effects of supplemental OptiPhos Plus phytase (Huvepharma, Peachtree ... more A 36-d experiment evaluated effects of supplemental OptiPhos Plus phytase (Huvepharma, Peachtree City, GA) on growth, bone mineralization, Ca and P digestibility of nursery-grower pigs. Individually housed crossbred pigs (n = 42; initial body weight [BW], 16.1 ± 0.4 kg) were randomly allotted to 7 dietary treatments based on BW and sex. A positive control (PC) diet was formulated to contain 0.601% Ca and 0.296% standardized total tract digestible (STTD) P, which were marginally lower than NRC (2012) requirement estimates for 25–50 kg pigs. A negative control (NC) diet (0.431% Ca and 0.164% STTD P) was developed by the removal of dicalcium phosphate from the PC diet and replacement with limestone and sand. Diets were: 1) PC, 2) NC, and 3–7) NC + 250, 500, 750, 1,000 and 1,500 FTU phytase/kg diet. On d 36, all pigs were euthanized for femur and metacarpal measures. Compared with NC, pigs fed the PC diet provided greater (P < 0.05) response for ADG (966 vs. 730 g/d), ADFI (1,660 vs....

Research paper thumbnail of Peripartum Ca and P homeostasis in multiparous sows fed adequate or excess dietary Ca

Animal, 2020

The recent increased prevalence of uterine prolapses in sows around parturition has led to infere... more The recent increased prevalence of uterine prolapses in sows around parturition has led to inferences that the prolapses may be associated with hypocalcemia. However, limited data are available to support that hypocalcemia occurs in sows. Hypocalcemia in dairy cows is associated with feeding excess dietary Ca during late gestation. The excess Ca is assumed to suppress homeostatic mechanisms critical to maintain serum Ca concentrations as the Ca demand increases during the early stages of lactation. In this experiment, sows were fed diets with excess Ca during late gestation and early lactation to assess the potential development of hypocalcemia in the peripartum period. Twelve crossbred (Large White × Landrace) multiparous gestating sows were fed a control diet (CON), 0.65% Ca to 0.38% standardized total tract digestible P (STTD P) and 0.67% Ca to 0.38% STTD P in gestation and lactation diets, respectively) or a high Ca diet (HCa, 1.75% Ca to 0.46% STTD P and 1.75% Ca to 0.45% STTD P in gestation and lactation diets, respectively). The diets were fed from gestation day 86 þ ± 1 until the end of lactation (27 þ ± 2 days period). On day 112 of gestation, indwelling venous catheters were placed in each sow. Blood samples were collected at 15-min intervals within four designated times (0700, 1000, 1300 and 1700 h) on gestation day 113 and lactation days 1, 3 and 5. Venous blood pH, gases (pO2, pCO2 and HCO3-), electrolytes (K+, Na+ and Cl-), ionized Ca (iCa), metabolites (glucose and lactate), plasma total Ca (tCa), and P were analyzed. Overall, sows fed HCa diet had greater (P < 0.001) concentrations of blood iCa and plasma tCa than sows fed CON diets. No clinical signs of Ca metabolism disorders were observed. Unexpectedly, concentrations of plasma P in sows fed HCa diets were lower (P < 0.001) than in sows fed CON diets. Plasma P tended to decrease (P = 0.057) as day of lactation increased. Differences between dietary treatments for blood pH, gases, electrolytes and metabolites were not detected (P > 0.05). No evidence for hypocalcemia was detected in peripartum sows fed CON or HCa diets. These data imply that excess Ca in late gestation diets did not result in hypocalcemia during the peripartum period. Future experiments should focus on factors other than hypocalcemia to identify causes of uterine prolapses in sows.

Research paper thumbnail of Reliability of Dietary Ca and P Levels and Bone Mineral Content as Predictors of Bone Mechanical Properties at Various Time Periods in Growing Swine

The Journal of Nutrition, 1986

Seventy-two growing pigs were fed one of nine dietary treatments that provided a range of Ca (0.4... more Seventy-two growing pigs were fed one of nine dietary treatments that provided a range of Ca (0.4%-1.2%) and P (0.4%-1.2%) levels arranged in a two-factor central composite design. Two pigs, per treatment after either 5 (T5) or 10 (TÕO) wk and four pigs per treatment after 15 (T15) wk were slaughtered, and the femur (F) and third (MT3) and fourth (MT4) metatarsal bones were collected for evaluation of mechanical properties (force, stress and modulus of elasticity), ash weight (ASHW), percent ash (PASH) and bone mineral content (BMC) using photon absorptiometry. Stepwise regression analysis utilized to generate best-fit equations predicted that dietary Ca and P levels could reliably predict force (fl2 = 0.83), ASHW (fi2 = 0.93) and BMC (fi2 = 0.89) of the MT3 bones but the prediction of force differed at the various time periods. Stress (fi2 = 0.41), the modulus of elasticity (fi2 = 0.29) and PASH (fi2 = 0.17) were not reliably predicted by dietary mineral levels. The amount of force withstood by the MT3 bone could be reliably predicted by BMC (fi2 = 0.90), but stress was not reliably predicted by BMC (fi2 = 0.40) even if dietary Ca levels were considered. These results indicated that dietary Ca levels between 0.6% and 1.2% and dietary P levels between 0.6% and 0.8% did not adversely affect growth, efficiency or bone development. The BMC, as determined by photon absorptiometry, was not a reliable predictor of bone strength.

Research paper thumbnail of Boron Supplementation of a Semipurified Diet for Weanling Pigs Improves Feed Efficiency and Bone Strength Characteristics and Alters Plasma Lipid Metabolites

The Journal of Nutrition, 2000

Research paper thumbnail of Chronic metabolic acid load induced by changes in dietary electrolyte balance increased chloride retention but did not compromise bone in growing swine

Journal of Animal Science, 2003

The effects of chronic dietary acid loads on shifts in bone mineral reserves and physiological co... more The effects of chronic dietary acid loads on shifts in bone mineral reserves and physiological concentrations of cations and anions in extracellular fluids were assessed in growing swine. Four trials were conducted with a total of 38 (8.16 ± 0.30 kg, mean ± SEM) Large White × Landrace × Duroc pigs randomly assigned to one of three dietary treatments. Semipurified diets, fed for 13 to 17 d, provided an analyzed dietary electrolyte balance (dEB, meq/kg diet = Na + + K + − Cl −) of −35, 112, and 212 for the acidogenic, control, and alkalinogenic diets, respectively. Growth performance, arterial blood gas, serum chemistry, urine pH, mineral balance, bone mineral content gain, bonebreaking strength, bone ash, and percentage of bone ash were determined. Dietary treatments created a range of metabolic acid loads without affecting (P >

Research paper thumbnail of Diminishing returns in weight, nitrogen, and lysine gain of pigs fed six levels of lysine from three supplemental sources

Journal of Animal Science, 1994

Diminishing returns responses to increments of lysine intake were evaluated in 82 crossbred barro... more Diminishing returns responses to increments of lysine intake were evaluated in 82 crossbred barrows (10.2 t SE = .31 kg) fed one of six concentrations of lysine expressed as 55, 80, 90, 100, 115, or 140% of a concentration (10.9 g k g of diet) that supported maximum weight gain. Supplemental lysine was provided from either soybean meal (SBM), SBM + synthetic lysine (SBM + L), or SBM + corn gluten meal (SBM + CGM) additions to a basal diet consisting of corn, minerals, and vitamins. A logistic equation was used to describe weight (kilograms/ day), nitrogen (gramslday) and lysine (gramdday) gain as a function of lysine intake from each diet. The parameter

Research paper thumbnail of Trace Minerals and OC in sows Zinpro J ANIM SCI-2013-Crenshaw-1255-69

Research paper thumbnail of the effect on sow and litter performance for three successive parities The addition of ground wheat straw as a fiber source in the gestation diet of sows and

Research paper thumbnail of Additions of Lysine, Tryptophan, Methionine and Isoleucine to All-Corn Diets for Finishing Swine

Research paper thumbnail of Combined Water and Fat Suppressed Proton Projection MRI (WASPI) and Micro CT Measurement of Bone Mineralization

H. Cao, J. Ackerman, T. D. Crenshaw, P. Dunning, M. Glimcher, and Y. Wu Department of Orthopaedic... more H. Cao, J. Ackerman, T. D. Crenshaw, P. Dunning, M. Glimcher, and Y. Wu Department of Orthopaedic Surgery, Children's Hospital, Boston, MA, United States, Harvard Medical School, Boston, MA, United States, Department of Radiology, Massachusetts General Hospital, Boston, MA, United States, Department of Animal Sciences, University of Wisconsin, Madison, WI, United States, Department of Radiology, Children's Hospital, Boston, MA, United States

Research paper thumbnail of In Vitro Fermentation of Swine Ileal Digesta Containing Oat Bran Dietary Fiber by Rat Cecal Inocula Adapted to the Test Fiber Increases Propionate Production But Fermentation of Wheat Bran Ileal Digesta Does Not Produce More Butyrate

The Journal of Nutrition, 2000

This experiment evaluated three hypotheses: i) production of propionate is increased during ferme... more This experiment evaluated three hypotheses: i) production of propionate is increased during fermentation of substrate containing oat bran (OB) 6 ; ii) production of butyrate is increased during fermentation of substrate containing wheat bran (WB) and iii) results of in vitro fermentations using physiological substrates and inocula agree with in vivo data. Ileal digesta collected from swine fed OB and WB were the substrates. Digesta was fermented for 0-96 h in an anaerobic in vitro system using inocula prepared from ceca of rats fed the same fiber sources. Carbohydrate and short-chain fatty acid (SCFA) contents in the fermentations were measured by gas chromatography. Fermentation of WB digesta did not produce more n-butyrate (P Ͼ 0.05) and was significantly slower (P Ͻ 0.05) than fermentation of OB digesta. OB digesta fermentation produced a significantly greater (P Ͻ 0.05) molar proportion of SCFA as propionate. Bacterial mass increased more and was maintained longer during fermentation of OB digesta than the WB digesta. Our results indicate that dilution of undigested WB fiber and not n-butyrate production is one mechanism by which WB may protect colonic mucosa; propionate production is increased during fermentation of ␤-glucan in OB; and an in vitro system using physiological sources of inoculum and substrate containing WB and OB yields results that agree with in vivo findings in humans and rats.

Research paper thumbnail of Postnatal Age and the Metabolism of Medium- and Long-Chain Fatty Acids by Isolated Hepatocytes from Small-for-Gestational-Age and Appropriate-for-Gestational-Age Piglets

The Journal of Nutrition, 1991

ABSTRACT Hepatocytes were isolated from full-term small-for-gestational-age (SGA) and appropriate... more ABSTRACT Hepatocytes were isolated from full-term small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) piglets at 6 or 48 h postpartum and incubated with 1 mmol/L [1-14C]-octanoate (8:0), -nonanoate (9:0) or -oleate (18:1). The cells oxidized [nmol 1-C/(h.10(6) cells)] 9:0 to carbon dioxide (12.5) and acid soluble products (28.9) faster than 8:0 (10.9, 20.6, respectively), and both were oxidized faster than 18:1 (3.9, 9.9) regardless of the piglet age or weight. Oleate accumulated in lipid products eightfold faster than did 8:0 and 9:0. No differences between cells from SGA and AGA piglets were detected. Recovery of 1-C in CO2 was 48% higher in incubations with cells from 48-h-old than from 6-h-old piglets. This increase was attributable to a 70% higher O2 consumption by 48-h-old cells. Theoretical O2 consumption rates were computed from the fatty acid flux data and compared with measured O2 consumption. Hepatocytes from SGA and AGA piglets were equally capable of satisfying greater than 75% of their energy needs from fatty acid oxidation. The O2 consumption attributable to 9:0 metabolism was 30% higher than observed for 8:0 and 18:1. All fatty acids apparently spared endogenous fuels to a greater degree in 6-h-old than in 48-h-old piglets.

Research paper thumbnail of Chapter 9 Use Of A Four Parameter Logistic Equation And Parameter Sharing To Evaluate Animal Responses To Graded Levels Of Nitrogen Or Amino Acids

Advances in Food and Nutrition Research, 1996

ABSTRACT This chapter discusses the use of a four parameter logistic equation and parameter shari... more ABSTRACT This chapter discusses the use of a four parameter logistic equation and parameter sharing to evaluate animal responses to graded levels of nitrogen or amino acids. The chapter provides the diminishing returns and dose-response relationships, the diminishing returns and protein quality, and the response of rats to each indispensable amino acid. A desirable feature of the statistical approach to define a linear-plateau relationship is that a single nutrient level is defined as the requirement to maximize growth. The change in limiting amino acid also explains the change in relative values of proteins from maintenance to maximum gain. Amino acids used with different efficiencies, can evoke a different diminishing returns response when fed to rats. A series of crystalline amino acid diets were used to examine the response of rats to each indispensable amino acid when limiting. Because of the curvilinear nature of the dose-response relationship, amino acid requirements should be estimated taking into account the decreasing efficiency associated with diminishing returns.

Research paper thumbnail of PSXVI-30 Supplemental Vitamin D3 for mediation of immune challenges in nursery pigs and subsequent growth responses

Journal of Animal Science, 2018

Research paper thumbnail of PSII-17 Phosphorus Release Values in Growing Pigs Fed Increments of Optiphos Plus Phytase in Pelleted Diets

Journal of Animal Science, 2021

The efficacy of phytase (Pase) from OptiPhos Plus G (Huvepharma, Peachtree City, GA) was compared... more The efficacy of phytase (Pase) from OptiPhos Plus G (Huvepharma, Peachtree City, GA) was compared to inorganic phosphorus (iP) supplements to assess phosphorus equivalency. In 6 replicate 28-d trials, 288 crossbred F2 (Duroc X LR X LW) pigs (20.0 kg, 6 pigs/pen, 48 pens) were randomly assigned to 1 of 8 diets. Pig sex was balanced within pens. Basal corn-soybean meal diets, formulated to exceed nutrient requirements except for Ca and P, supplied 1.30% lysine from the same amounts of all ingredients. Sand was used to balance variable amounts of monocalcium phosphate and limestone. Diets supplied either 0.061, 0.156, or 0.241% iP from monocalcium phosphate or increments of 250, 500, 750, 1,000 and 1,500 FTU/kg from Pase. All diets were pelleted (160°F, 2.5 tons/hr). The modified pellet durability index averaged 92.8% and 88.7% for all diets in each of 2 mixes. Non-linear growth responses to increments of iP and Pase were detected (P < 0.05). Using nonlinear regression models, maxim...

Research paper thumbnail of Nutritional composition, gross energy concentration, and in vitro digestibility of dry matter in 46 sources of bakery meals

Journal of Animal Science, 2018

Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies ... more Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies depending on where in the United States the meal is produced due to different raw materials being used in the production of the meals. Forty-six samples of bakery meal were collected from feed mills located in the swine producing states in the United States. Based on the state where samples were collected, they were grouped into 5 regions: 1) AL, DE, GA, NC, PA, and VA (10 samples); 2) CO, MO, OK, and TX (10 samples); 3) IN, KY, OH, and TN (8 samples); 4) IA (11 samples); and 5) MN (7 samples). All samples were analyzed for proximate components, GE, AA, carbohydrates, and minerals, and IVDMD and in vitro energy digestibility (IVGED) were also determined. Results indicated that the average concentration of DM was (91.84 ± 1.29%) and there was no difference among regions. The concentration of ash in bakery meal from MN was greater (P < 0.05) than in meals from other regions, but for all other proximate components, no differences among sources were observed. The average concentration (DM basis) of CP (12.20 ± 2.16%), acid hydrolyzed ether extract (AEE, 9.38 ± 1.95%), starch (44.61 ± 5.47%), and NDF (13.77 ± 4.23%) indicated that bakery meal

Research paper thumbnail of Nonruminant Nutrition: Enzymes

A total of 180, 18-d crossbred pigs (GAP English Belle × Duroc) with BW of 7.0 ± 1.1 kg were rand... more A total of 180, 18-d crossbred pigs (GAP English Belle × Duroc) with BW of 7.0 ± 1.1 kg were randomly allotted to 6 treatments with 5 replicate pens/treatment for 3 phases with 11, 11 and 12 d in each feeding phase, respectively. Six corn-soybean meal mash diets were formulated: a positive control (PC) diet (0.32% available P (aP); met NRC, 1998 recommendations), a negative control (NC) diet with approximately 10% reduction of aP (0.28% aP), NC + 200 FTU/kg Quantum (QP: E. coli phytase expressed in Pichia pastoris), NC + 500 FTU/kg QP, NC + 1,250 FTU/kg QP, and NC + 500 FTU/kg Natuphos (NP; fungal phytase expressed in Aspergillus niger). On d 42, 9 pigs from each treatment were randomly selected and euthanized for metatarsal collection to measure breaking strength and to determine ash and P content. Ash and P content of the metatarsal bone was not different among the dietary treatments. However, sex influenced (P < 0.01) metatarsal ash, and P content. In general, the average ash ...

Research paper thumbnail of Bone mechanical properties after exercise training in young and old rats

Journal of Applied Physiology, 1990

The effects of a 10-wk training regimen on the mechanical properties of the femur and humerus wer... more The effects of a 10-wk training regimen on the mechanical properties of the femur and humerus were evaluated in 2.5- and 25-mo-old Fischer 344 female rats. The rats trained on a rodent treadmill 5 days/wk for 10 wk. Duration, grade, and speed increased until the rats maintained 1 h/day at 15% grade and either 15 m/min (old rats) or 36 m/min (young rats). Excised bones were mechanically tested with a 3-point flexure test for mechanical properties of force, stress, and strain. Fat-free dry weight (FFW) and moment of inertia were also obtained. With aging, similar increases were observed in both the femur and humerus for FFW, moment of inertia, and force. Ultimate stress was reduced in the senescent femur while strain was elevated; a similar but nonsignificant trend was observed in the humerus. Irrespective of age, training increased FFW in the femur and, to a lesser degree, in the humerus. Breaking force was elevated for both bones after training. In young and old bones, the training-...

Research paper thumbnail of Bone Strength as a Trait for Assessing Mineralization in Swine: a Critical Review of Techniques Involved

Journal of Animal Science, 1981

Research paper thumbnail of Evaluating the effects of supplemental B vitamins in practical swine diets during the starter and grower-finisher periods A regional study

Journal of Animal Science, 2007

Two experiments were conducted to evaluate dietary fortification levels of a B vitamin premix for... more Two experiments were conducted to evaluate dietary fortification levels of a B vitamin premix for starter and grower-finisher pigs on subsequent performance responses. The objective was to determine whether the modern pig requires higher dietary levels of B vitamins than estimated by the NRC (1998). Both experiments added fat-soluble vitamins at the requirement levels (NRC, 1998) in all diets, whereas the B vitamins were added at 0, 100, 200, or 400% of the total NRC (1998) requirement levels for the starter and grower pig. ndigenous vitamin contributions from the feed grains were not included in the estimates. Each station used the same vitamin premixes but incorporated its own grain sources in the diets. The first experiment was conducted across 7 stations (

Research paper thumbnail of 95 Growth Performance, Bone Mineralization, and Nutrient Digestibility of Nursery-grower Pigs Fed Phytase-supplemented Calcium and Phosphorus-deficient Diets

Journal of Animal Science, 2021

A 36-d experiment evaluated effects of supplemental OptiPhos Plus phytase (Huvepharma, Peachtree ... more A 36-d experiment evaluated effects of supplemental OptiPhos Plus phytase (Huvepharma, Peachtree City, GA) on growth, bone mineralization, Ca and P digestibility of nursery-grower pigs. Individually housed crossbred pigs (n = 42; initial body weight [BW], 16.1 ± 0.4 kg) were randomly allotted to 7 dietary treatments based on BW and sex. A positive control (PC) diet was formulated to contain 0.601% Ca and 0.296% standardized total tract digestible (STTD) P, which were marginally lower than NRC (2012) requirement estimates for 25–50 kg pigs. A negative control (NC) diet (0.431% Ca and 0.164% STTD P) was developed by the removal of dicalcium phosphate from the PC diet and replacement with limestone and sand. Diets were: 1) PC, 2) NC, and 3–7) NC + 250, 500, 750, 1,000 and 1,500 FTU phytase/kg diet. On d 36, all pigs were euthanized for femur and metacarpal measures. Compared with NC, pigs fed the PC diet provided greater (P < 0.05) response for ADG (966 vs. 730 g/d), ADFI (1,660 vs....

Research paper thumbnail of Peripartum Ca and P homeostasis in multiparous sows fed adequate or excess dietary Ca

Animal, 2020

The recent increased prevalence of uterine prolapses in sows around parturition has led to infere... more The recent increased prevalence of uterine prolapses in sows around parturition has led to inferences that the prolapses may be associated with hypocalcemia. However, limited data are available to support that hypocalcemia occurs in sows. Hypocalcemia in dairy cows is associated with feeding excess dietary Ca during late gestation. The excess Ca is assumed to suppress homeostatic mechanisms critical to maintain serum Ca concentrations as the Ca demand increases during the early stages of lactation. In this experiment, sows were fed diets with excess Ca during late gestation and early lactation to assess the potential development of hypocalcemia in the peripartum period. Twelve crossbred (Large White × Landrace) multiparous gestating sows were fed a control diet (CON), 0.65% Ca to 0.38% standardized total tract digestible P (STTD P) and 0.67% Ca to 0.38% STTD P in gestation and lactation diets, respectively) or a high Ca diet (HCa, 1.75% Ca to 0.46% STTD P and 1.75% Ca to 0.45% STTD P in gestation and lactation diets, respectively). The diets were fed from gestation day 86 þ ± 1 until the end of lactation (27 þ ± 2 days period). On day 112 of gestation, indwelling venous catheters were placed in each sow. Blood samples were collected at 15-min intervals within four designated times (0700, 1000, 1300 and 1700 h) on gestation day 113 and lactation days 1, 3 and 5. Venous blood pH, gases (pO2, pCO2 and HCO3-), electrolytes (K+, Na+ and Cl-), ionized Ca (iCa), metabolites (glucose and lactate), plasma total Ca (tCa), and P were analyzed. Overall, sows fed HCa diet had greater (P < 0.001) concentrations of blood iCa and plasma tCa than sows fed CON diets. No clinical signs of Ca metabolism disorders were observed. Unexpectedly, concentrations of plasma P in sows fed HCa diets were lower (P < 0.001) than in sows fed CON diets. Plasma P tended to decrease (P = 0.057) as day of lactation increased. Differences between dietary treatments for blood pH, gases, electrolytes and metabolites were not detected (P > 0.05). No evidence for hypocalcemia was detected in peripartum sows fed CON or HCa diets. These data imply that excess Ca in late gestation diets did not result in hypocalcemia during the peripartum period. Future experiments should focus on factors other than hypocalcemia to identify causes of uterine prolapses in sows.

Research paper thumbnail of Reliability of Dietary Ca and P Levels and Bone Mineral Content as Predictors of Bone Mechanical Properties at Various Time Periods in Growing Swine

The Journal of Nutrition, 1986

Seventy-two growing pigs were fed one of nine dietary treatments that provided a range of Ca (0.4... more Seventy-two growing pigs were fed one of nine dietary treatments that provided a range of Ca (0.4%-1.2%) and P (0.4%-1.2%) levels arranged in a two-factor central composite design. Two pigs, per treatment after either 5 (T5) or 10 (TÕO) wk and four pigs per treatment after 15 (T15) wk were slaughtered, and the femur (F) and third (MT3) and fourth (MT4) metatarsal bones were collected for evaluation of mechanical properties (force, stress and modulus of elasticity), ash weight (ASHW), percent ash (PASH) and bone mineral content (BMC) using photon absorptiometry. Stepwise regression analysis utilized to generate best-fit equations predicted that dietary Ca and P levels could reliably predict force (fl2 = 0.83), ASHW (fi2 = 0.93) and BMC (fi2 = 0.89) of the MT3 bones but the prediction of force differed at the various time periods. Stress (fi2 = 0.41), the modulus of elasticity (fi2 = 0.29) and PASH (fi2 = 0.17) were not reliably predicted by dietary mineral levels. The amount of force withstood by the MT3 bone could be reliably predicted by BMC (fi2 = 0.90), but stress was not reliably predicted by BMC (fi2 = 0.40) even if dietary Ca levels were considered. These results indicated that dietary Ca levels between 0.6% and 1.2% and dietary P levels between 0.6% and 0.8% did not adversely affect growth, efficiency or bone development. The BMC, as determined by photon absorptiometry, was not a reliable predictor of bone strength.

Research paper thumbnail of Boron Supplementation of a Semipurified Diet for Weanling Pigs Improves Feed Efficiency and Bone Strength Characteristics and Alters Plasma Lipid Metabolites

The Journal of Nutrition, 2000

Research paper thumbnail of Chronic metabolic acid load induced by changes in dietary electrolyte balance increased chloride retention but did not compromise bone in growing swine

Journal of Animal Science, 2003

The effects of chronic dietary acid loads on shifts in bone mineral reserves and physiological co... more The effects of chronic dietary acid loads on shifts in bone mineral reserves and physiological concentrations of cations and anions in extracellular fluids were assessed in growing swine. Four trials were conducted with a total of 38 (8.16 ± 0.30 kg, mean ± SEM) Large White × Landrace × Duroc pigs randomly assigned to one of three dietary treatments. Semipurified diets, fed for 13 to 17 d, provided an analyzed dietary electrolyte balance (dEB, meq/kg diet = Na + + K + − Cl −) of −35, 112, and 212 for the acidogenic, control, and alkalinogenic diets, respectively. Growth performance, arterial blood gas, serum chemistry, urine pH, mineral balance, bone mineral content gain, bonebreaking strength, bone ash, and percentage of bone ash were determined. Dietary treatments created a range of metabolic acid loads without affecting (P >

Research paper thumbnail of Diminishing returns in weight, nitrogen, and lysine gain of pigs fed six levels of lysine from three supplemental sources

Journal of Animal Science, 1994

Diminishing returns responses to increments of lysine intake were evaluated in 82 crossbred barro... more Diminishing returns responses to increments of lysine intake were evaluated in 82 crossbred barrows (10.2 t SE = .31 kg) fed one of six concentrations of lysine expressed as 55, 80, 90, 100, 115, or 140% of a concentration (10.9 g k g of diet) that supported maximum weight gain. Supplemental lysine was provided from either soybean meal (SBM), SBM + synthetic lysine (SBM + L), or SBM + corn gluten meal (SBM + CGM) additions to a basal diet consisting of corn, minerals, and vitamins. A logistic equation was used to describe weight (kilograms/ day), nitrogen (gramslday) and lysine (gramdday) gain as a function of lysine intake from each diet. The parameter

Research paper thumbnail of Trace Minerals and OC in sows Zinpro J ANIM SCI-2013-Crenshaw-1255-69