Biomedical subjects

P R Henry

Publications and source records attributed to P R Henry.

At least 19 recordsLinked to original sources

PubMed1997

Estimation of relative bioavailability of nutrients using SAS procedures.

The General Linear Models procedure (PROC GLM) in SAS/STAT software can be programmed to perform the standard statistical analyses used for relative bioavailability studies. The first steps are validity checks to test for statistical validity (linearity), fundamental validity (intersection of regression lines at 0 supplemental level), and equality of the basal diet mean to the point of intersection. The CLASS variable capabilities of PROC GLM can be exploited to expedite these tests. After the validity checks, the GLM procedure can be used to obtain parameter estimates for calculation of relative bioavailability. Optional output provides an inverse matrix to calculate standard errors of slopes and slope ratios. Logarithmic and other transformations of the dependent variable to reduce variance heterogeneity or achieve linearity for subsequent calculation of appropriate bioavailability values also can be accomplished within the SAS System. When nonlinear regression models are more appropriate than linear models, the NLIN procedure can be used.

Animals↗

PubMed1997

Relative bioavailability of supplemental inorganic zinc sources for chicks.

Three experiments were conducted to investigate the relative bioavailability of reagent-grade (RG) and feed grade (FG) Zn sources for 1-d-old broiler chicks. In Exp. 1, 13 treatments included a basal corn-soybean meal diet (63 ppm Zn) or the basal diet supplemented with 400, 800, or 1,200 ppm Zn from RG sulfate, basic carbonate, oxide, or metal and fed for 20 d. Using multiple regression slope ratios with Zn sulfate set at 100%, bioavailability estimates were 78, 77, and 46% for carbonate, oxide, and metal, respectively. In Exp. 2, chicks were allotted randomly to 16 treatments that included a basal corn-soybean meal diet (75 ppm Zn) or basal diet supplemented with 300, 600, or 900 ppm Zn as either RG sulfate, FG sulfate-A, FG sulfate-B, FG oxide-A, or FG oxide-B and fed for 21 d. Multiple linear regression slope ratios gave relative estimates of 99, 81, 78, and 54% for sulfate-A, sulfate-B, oxide-A, and oxide-B sources, respectively, with RG sulfate set at 100%. In Exp. 3, chicks were fed a basal corn-soybean meal diet (35 ppm Zn) or the basal diet supplemented with 40, 80, or 120 ppm Zn from RG Zn sulfate, FG sulfate, or FG oxide and fed for 20 d. Multiple regression slope ratios with RG sulfate set at 100% gave relative bioavailability estimates of 94 and 74% for the FG sulfate and oxide, respectively. Bioavailability estimates were similar when Zn was supplemented to diets at high or low concentrations.

Animals↗

PubMed1996

Effect of dietary iron concentration, age, and length of iron feeding on feed intake and tissue iron concentration of broiler chicks for use as a bioassay of supplemental iron sources.

Three experiments were conducted with day-old chicks to study the effects of dietary Fe concentration and age on Fe accumulation in tissues as an estimate of supplemental Fe bioavailability, and of delaying the time of initial high Fe supplementation up to 7 d of age on feed intake to 3 wk of age. In Experiment 1, chicks were fed a basal corn-soybean meal diet (188 mg/kg Fe, DM basis) or the basal supplemented with 400, 600, or 800 mg/kg added Fe as reagent grade FeSO4.7H2O for either 1, 2, or 3 wk. Dietary Fe depressed (P < 0.001) feed intake and body weight gain, especially at 3 wk. Kidney Fe concentrations increased linearly (P < 0.001) with increasing dietary Fe. Liver Fe concentration also increased linearly, but reached a plateau in birds fed 600 mg/kg Fe. Bone Fe increased linearly (P < 0.05) at 1 wk, but not at 2 or 3 wk. Liver and kidney Fe regressed on daily Fe intake had the best fit to a linear model at 2 wk. In Experiment 2, chicks were fed either a basal diet (320 mg/kg Fe, DM basis) continuously, the basal supplemented with 800 mg/kg added Fe as FeSO4.7H2O continuously, or were started on the control diet and switched to the high Fe diet on Day 3, 5, or 7. Feed intake was lower (P < 0.05) in birds started on Fe on Days 1 or 3, but delaying feeding of high Fe diets until Day 5 resulted in intake at 3 wk similar to that of birds fed the basal diet. In Experiment 3, the basal diet (123 mg/kg Fe) was fed to chicks for 6 d, then experimental diets were fed for 14 d. Diets were the basal or basal supplemented with 400, 600, or 800 mg/kg added Fe as reagent grade or feed grade Fe sulfate or an Fe methionine complex. When estimated from regression of log10 liver Fe concentration on total analyzed dietary Fe concentration, relative bioavailability was set at 100% for reagent grade Fe sulfate, and the feed grade sulfate was 92.3% and Fe methionine was 88.3%. Liver Fe concentrations may be useful criteria for determining Fe bioavailability and 2 wk of feeding was the optimal time required for such a bioassay. Delaying feeding high Fe diets until 5 d of age alleviated the decreased feed intake associated with high Fe diets.

Aging↗

PubMed1992

Relative bioavailability of manganese from a manganese-methionine complex and inorganic sources for ruminants.

Two experiments were conducted to study the relative bioavailability of Mn from a feed grade Mn-Met complex or from two feed grade MnO sources using reagent grade MnSO4.H2O as the standard. In each experiment, 42 crossbred wether lambs were fed one of seven dietary treatments for 21 d and then killed; liver, kidneys, and right metacarpus were removed for MN analysis. In Experiment 1, treatment included the basal diets (34.4 ppm of Mn, DM basis) alone or supplemented with 900, 1800, or 2700 ppm of Mn as reagent grade MnSO4.H2O or feed grade Mn-Met complex. In Experiment 2, the basal diet (31.5 ppm of Mn, DM basis) was fed alone or was supplemented with 900, 1800, or 2700 ppm of Mn as reagent grade MnSO4.H2O or 1800 ppm of Mn as feed grade Mn-Met, feed grade MnO A, or feed grade MnO B. The overall estimated relative bioavailabilities based on multiple linear regression coefficients of bone, kidney, and log-transformed liver Mn concentrations on total dietary Mn concentrations were 100, 121, 70, and 53% for MnSO4.H2O, Mn-Met complex, MnO A, and MnO B, respectively.

Absorption↗

PubMed1991

Effect of time and sex on tissue selenium concentrations in chicks fed practical diets supplemented with sodium selenite or calcium selenite.

An experiment was conducted with 384 1-d-old male and female broiler-chicks. The basal corn-soybean meal diet (.07 ppm Se DM basis) was supplemented with 0, .1, .2, or .3 ppm added Se as either sodium selenite (Na2SeO3) or calcium selenite (CaSeO3), and fed for 1, 3, or 5 wk. There was no effect of Se source or level on feed intake or gain, but males consumed more (P less than .01) feed than females. There was no effect (P greater than .10) of sex or Se source on plasma, liver, or kidney Se concentration. The Se concentration of all tissues increased (P less than .01) with time and increasing dietary Se concentration. Based on multiple regression slope ratios of liver, kidney, and plasma Se concentrations, Se from CaSeO3 was as available (103%) as Se from Na2SeO3.

Aging↗

PubMed1991

Estimation of the relative bioavailability of inorganic copper sources for chicks using tissue uptake of copper.

An experiment was conducted with 208 day-old male Cobb feather-sexed chicks to study tissue accumulation of Cu as an estimate of biological availability of inorganic Cu sources for chicks. Chicks were allotted randomly to dietary treatments that included an unsupplemented basal corn-soybean meal diet (11.1 mg/kg Cu, DM basis) or this basal diet supplemented with 150, 300 or 450 mg/kg Cu either as reagent-grade acetate or feed grade oxide, carbonate or sulfate. Chicks were housed in batteries and allowed ad libitum access to feed and tap water for 21 d. Liver Cu was not affected by dietary Cu from the oxide source, but it increased (P less than .001) with increasing dietary Cu from all other sources. Bone Cu was lower (P less than .05) in chicks fed 150 mg/kg Cu compared to other dietary levels of Cu but was not influenced (P greater than .10) by Cu source. Using the slope-ratio technique from regression of log liver Cu on mean daily Cu intake with Cu from acetate set at 100%, the relative biological availability values were estimated to be 88.5 and 54.3% for sulfate and carbonate, respectively, and oxide was essentially unavailable.

Animals↗

PubMed1989

Estimation of the relative bioavailability of manganese sources for sheep.

The relative biological availability of Mn in reagent-grade (RG) Mn sources was tested using 41 Rambouillet crossbred wether lambs in a completely randomized design. Lambs were fed a basal corn-soybean meal-cottonseed hull diet (37.6 ppm Mn, DM basis) or this basal diet supplemented with 0, 1,500, 3,000 or 4,500 ppm Mn from RG MnSO4.H20 or 3,000 ppm Mn from RG MnO, MnO2 and MnCO3. Feed intake was restricted to 1,000 g/hd daily during the 21-d experimental period. There was a decrease (P less than .01) in daily feed intake by sheep fed 4,500 ppm Mn from MnSO4. Liver, kidney and bone Mn concentrations increased (P less than .05) with MnSO4 supplementation. Liver was most responsive to dietary Mn, followed by kidney and bone. Based on multiple linear regression slopes for liver, kidney and bone Mn concentrations, relative bioavailability of Mn from MnO, MnO2 and MnCO3 averaged 57.7, 32.9 and 27.8%, compared with 100% for MnSO4.

Animal Feed↗

PubMed1989

Comparison of methods to determine relative bioavailability of magnesium in magnesium oxides for ruminants.

Two Mg balance trials were conducted with wethers to compare relative bioavailability of Mg in several Mg oxides with that of reagent grade sulfate as determined by different methods. In Experiment 1,600 ppm Mg as sulfate or four feed grade oxides varying in origin and particle size were added to a semi-purified basal diet (200 ppm Mg). Diets were fed at 800 g/d to 30 crossbred wethers during the 14-d trial and fecal and urinary collections were made during the last 7 d. In Experiment 2, the basal corn-soybean meal-cottonseed hull diet (1387 ppm Mg) was supplemented with 0, 700, 1400, or 2100 ppm added Mg as reagent grade sulfate or 1400 ppm Mg as three of the oxides from Experiment 1 and fed at 1000 g/d to 35 wethers. Urine was collected daily for 10 d and feces were collected on d 7 through 10. In Experiments 1 and 2, absorption of Mg from the oxide of brine origin and larger particle size distribution was lower than that from sulfate, but there was no difference in absorption for sheep fed oxides derived from sea water or calcined magnesite. In Experiment 2, urinary Mg excretion on d 4 and 5 of the collection was lower for sheep fed the brine oxide than for those fed sulfate or oxide from calcined magnesite. Urinary Mg excretion on d 4 and 5 following addition of 1400 ppm Mg to practical diets could be used to predict bioavailability of Mg.

Animal Feed↗

PubMed1989

Relative bioavailability of manganese in a manganese-methionine complex for broiler chicks.

The relative bioavailability of Mn from reagent grade Mn monoxide and feed grade Mn-methionine was compared with that from reagent grade Mn sulfate using 288 one-day-old male Cobb chicks. The basal corn-soybean meal diet (93 ppm Mn dry matter basis) was supplemented with 0, 700, 1,400, and 2,100 ppm Mn as Mn sulfate monohydrate, Mn oxide, or Mn-methionine. Additional diets contained 700, 1,400, and 2,100 ppm Mn as sulfate or oxide in combination with .16, .32, or .48% added DL-methionine, respectively, to equalize methionine concentrations in Mn-methionine-containing diets. Diets were fed ad libitum for 3 wk. Tibia and kidney Mn concentrations increased linearly (P less than .001) as dietary Mn increased. Addition of methionine to diets containing sulfate and oxide did not influence (P greater than .10) tissue Mn concentrations. Based on slope ratios from multiple linear regression of bone and kidney Mn concentrations on added dietary Mn from various sources, the respective relative bioavailability values were 96 and 86% from Mn oxide and 108 and 132% from Mn-methionine compared with 100% from Mn sulfate. Except for the first, all values were significantly different from 100%. Thus, Mn from Mn oxide is significantly less available and Mn from Mn-methionine is significantly more available than that from Mn sulfate monohydrate.

Animals↗

PubMed1989

Bioavailability of manganese from feed grade manganese oxides for broiler chicks.

An experiment was conducted to study the relative biological availability of Mn from inorganic Mn sources using 288, 1-day-old male Cobb feather-sexed chicks. Chicks were fed a basal corn-soybean meal diet (82.5 ppm Mn, as-fed basis) ad libitum or the basal diet supplemented with 0, 1,000, 2,000, or 3,000 ppm Mn from reagent grade (RG) MnSO4.H2O, MnO RG, or feed grade (FG) Oxide A, B, or C for 21 days. Bone and kidney Mn concentrations were used to estimate bioavailability. Manganese source and level had no effect on chick performance. Uptake of dietary Mn by bone and kidney from all sources was highly linear (P less than .001). Based on multiple linear regression slopes from bone Mn concentrations, the relative bioavailability values of MnO RG and MnO FG A, B, and C were 81.9 +/- 6.0, 93.1 +/- 6.7, 75.0 +/- 3.6, and 70.3 +/- 5.7, respectively, compared with 100% for MnSO4; those based on kidney Mn were 85.7 +/- 7.9, 68.0 +/- 7.5, 52.2 +/- 4.2, and 53.0 +/- 7.3, respectively.

Animal Feed↗

PubMed1988

Effects of dietary phosphorus, soil ingestion and dietary intake level on performance, phosphorus utilization and serum and alimentary tract mineral concentrations in lambs.

Two experiments were conducted with lambs fed concentrate-based diets to study the effects of dietary P and soil ingestion on performance, P utilization and mineral composition of serum and alimentary tract contents. In Exp. 1, 20 wether lambs were fed diets for 21 d in a 2 X 2 factorial arrangement of treatments with .2 or .3% total dietary P and O or 9% added Florida Ultisol (highly weathered soil with high P-fixation capacity) containing 4,600 and 6,400 mg/kg total Al and Fe, respectively. True P absorption increased (P less than .05) from 30 to 42% and from 37 to 54% when soil was added to the basal and high P diets, respectively. In Exp. 2, 24 wether lambs were assigned randomly to a 2 X 2 X 2 factorial arrangement of treatments. Lambs were fed during a 70-d period using diets described previously on either a restricted or an ad libitum basis. Soil increased Fe concentration in ruminal fluid (P less than .05) and ash percentage (P less than .001) in ruminal solids and feces. Aluminum concentration in ruminal solids and feces and Fe in ruminal solids were increased (P less than .001) by soil addition, whereas concentrations of Ca, Mg, P, Zn, Cu and Mn in ruminal solids and feces were decreased (P less than .01) by soil addition. There were time X P interactions on serum inorganic P (P less than .01) and Mg (P less than .05) concentrations. Although high in P-fixing capacity, soil fed to lambs in these experiments improved P utilization. Lambs appeared to be able to adapt to changes in intake of dietary minerals in soil, possibly through adaptation of ruminal microflora or a redistribution of body mineral pools.

Aluminum↗

PubMed1988

Effects of time and dietary selenium concentration as sodium selenite on tissue selenium uptake by sheep.

Thirty crossbred wethers (60 kg avg initial wt) were used to study the time-dose response to dietary Se as sodium selenite (Na2SeO3). Sheep were fed a basal diet (.20 mg/kg Se, M basis) for 10 d; three wethers were killed and tissues were collected for controls. The remaining 27 sheep were assigned randomly to diets supplemented with either 3, 6 or 9 mg/kg Se (as-fed basis) from reagent grade Na2SeO3 and fed for 10, 20 or 30 d. Feed offered was restricted to 1,200 g daily and tap water was available ad libitum. Sheep were stunned and killed by exsanguination and liver, kidney, muscle, heart and spleen were removed and frozen for Se analysis. No toxic effects were noted as expressed by feed intake or hemoglobin concentration. Added dietary Se increased Se linearly (P less than .01) in liver, kidney, and serum. Selenium in liver, kidney and serum also increased (P less than .01) as time advanced. Serum, liver and kidney were more sensitive to dietary Se than were muscle, heart and spleen. Ten days appeared to be an adequate length of time for further Se bioassay studies of this nature. Reagent grade Na2SeO3 was nontoxic when fed to sheep for 30 d at levels up to 90 times the Se requirement.

Animals↗

PubMed1988

Estimation of the relative biological availability of inorganic selenium sources for ruminants using tissue uptake of selenium.

An experiment was conducted to estimate the relative bioavailability of inorganic Se sources based on tissue Se deposition following supplementation at high dietary levels. Twenty-eight crossbred wethers averaging 50 kg initial weight were assigned randomly to seven treatments that were fed for 10 d. The basal diet contained .18 mg/kg Se (DM basis). Dietary Se was added at 0, 3, 6 or 9 mg/kg as reagent grade sodium selenite (Na2SeO3) and 6 mg/kg from either calcium selenite (CaSeO3), Na2SeO3 + fumed amorphous carrier or sodium selenate (Na2SeO4). There were four sheep per treatment group, housed in individual, raised pens with slatted floors. Daily feed intake was restricted to 1,200 g and tap water was available ad libitum. The basal diet was fed for a 10-d adjustment period, then sheep were fed experimental diets for 10 d. At the termination of the experiment, blood samples were taken; sheep were stunned and killed, and livers and kidneys were removed and frozen for Se analysis. There was a linear (P less than .001) uptake of Se in liver, kidney and serum. The CaSeO3 and Na2SeO4 sources resulted in greater (P less than .05) Se concentrations in liver and kidney than did Na2SeO3, but these differences were not significant when the analyzed dietary Se concentrations were used as a covariate in the statistical model. Based on linear and multiple linear regression slopes and average increases in serum, liver and kidney Se concentrations, estimated relative bioavailability values corrected for analyzed dietary concentration, were 100, 101, 90 and 133 for Na2SeO3, CaSeO3, Na2SeO3 + carrier and Na2SeO4, respectively.

Animals↗

PubMed1988

Estimation of the relative bioavailability of inorganic selenium sources for poultry. 1. Effect of time and high dietary selenium on tissue selenium uptake.

An experiment was conducted with male broiler-type chicks to study the effect of time and high dietary Se concentration on tissue Se uptake. A basal corn-soybean meal diet (.2 mg/kg Se, DM basis) was supplemented with 0, 3, 6, or 9 mg/kg Se (as-fed basis) as Na2SeO3 and fed ad libitum for 1, 2, or 3 wk. No toxic effect of Se was observed as expressed by mortality; however, there was a reduction in daily feed intake (P less than .01) at 6 and 9 mg/kg added Se, particularly at 3 wk, suggesting developing toxicosis. Selenium concentration in all tissues studied increased linearly (P less than .001) as dietary Se increased, especially in kidney and liver. Coefficients of determination and lambda criterion values were greatest in plasma, followed by liver, muscle, and kidney. It appeared that 1 wk would be an adequate length of time for further Se bioavailability studies based on tissue Se uptake from diets containing 3 to 9 mg/kg added Se.

Animals↗

PubMed1988

Estimation of the relative bioavailability of inorganic selenium sources for poultry. 2. Tissue uptake of selenium from high dietary selenium concentrations.

An experiment was conducted with 192 day-old male Cobb chicks to study tissue uptake of Se as an estimate of the bioavailability of supplemental inorganic Se sources fed at high dietary concentrations. A basal corn-soybean meal diet (.18 mg Se/kg diet, dry matter basis) was supplemented with 0, 3, 6, or 9 mg Se/kg diet (as-fed basis) as either reagent grade Na2SeO3, CaSeO3, or Na2SeO3 plus fumed amorphous carrier or 6 mg Se/kg diet as either Na2SeO4 or Se metal, and fed for 1 wk. No toxic effects were noted as expressed by mortality; however, there was a reduction (P less than .01) in feed intake and daily gain when 9 mg Se/kg diet was fed, suggesting onset of toxicosis. Selenium concentration in liver, kidney, muscle, and plasma increased linearly (P less than .01) as dietary Se increased from all sources. Selenium metal produced lower (P less than .01) Se concentrations in kidney and muscle than other supplemental sources. Multiple regression slope ratios were used to estimate relative bioavailability values of 100, 103, 99, 112, and 83 for Na2SeO3, CaSeO3, Na2SeO3 + carrier, Na2SeO4, and Se metal, respectively. When these ratios were corrected for the analyzed dietary Se concentration, relative values were 100, 96, 94, 109, and 81 for the above sources, respectively.

Animals↗

PubMed1988

More-sensitive enzyme-multiplied immunoassay technique for procainamide and N-acetylprocainamide in plasma, serum, and urine.

A commercially available (Syva Co.) enzyme-multiplied immunoassay technique (EMIT) for the quantitative determination of procainamide (PA) and N-acetylprocainamide (NAPA) was modified to allow automated quantitative analysis of approximately 100 samples per day, in a working range of 0.1 to 2.0 micrograms/mL. Such a test was needed to evaluate the pharmacokinetic characteristics of controlled-release dosage forms characterized by long half-lives at low plasma concentration. Analytical recovery of PA and NAPA from serum, plasma, and urine was satisfactory, but at extreme ratios for PA:NAPA the accuracy of determining the lower-concentration component became unsatisfactory. In fact, however, we found no such ratios in 5400 clinical samples assayed by this procedure.

Acecainide↗

PubMed1987

Effect of antibiotics on tissue trace mineral concentration and intestinal tract weight of broiler chicks.

Two experiments were conducted with broiler-type chicks to determine the effect of antibiotics on intestinal weight and kidney, bone, and liver trace mineral concentrations. All antibiotics were in diets at the manufacturers' recommendations. Feed intake of experimental diets (antibiotics or non-treated control) was restricted to 90% of that of an additional group fed the control diet ad libitum. Feed intake, weight gain, and feed efficiency were not affected (P greater than .10) by dietary treatments. Virginiamycin decreased intestinal weight an average of 19% as compared with 14% for bambermycins and oxytetracycline, 6% for Zn bacitracin, and 18% for lincomycin. Except for Zn bacitracin, all antibiotics produced intestinal weights which were lower (P less than .01) than those of controls. Only virginiamycin increased (P less than .01) kidney Mn concentration. Bone Mn concentration was greater (P less than .01) for virginiamycin than bambermycins or oxytetracycline in Experiment 2, and greater (P less than .05) for lincomycin than virginiamycin or Zn bacitracin in Experiment 2. Feeding Zn bacitracin increased (P less than .01) bone Zn concentration whereas feeding virginiamycin caused a decline (P less than .05) in bone Zn concentration in Experiment 1. There were no differences in Cu, Zn, or Fe concentrations in liver or kidney.

Animals↗

PubMed1986

Kinetic model of whole-body vanadium metabolism: studies in sheep.

A compartmental model for vanadium metabolism in sheep has been proposed. The model is consistent with data obtained from sheep fed a control diet (2.6 ppm vanadium) containing 0 or 200 ppm supplemental vanadium. Sheep were administered 48V dioxovanadium either orally or intravenously. Blood, feces, and urine radioactivity were monitored for 6 days postdosing. Several new insights regarding vanadium metabolism are suggested and tested against the data using the model. Some of these include significant absorption of 48V occurs from the upper gastrointestinal tract; an in vivo process is necessary in order for 48V dioxovanadium to be converted into a more biologically reactive species; at steady state the upper and lower gastrointestinal tracts contain at least 10- and 100-fold more mass of vanadium, respectively, than does blood. No statistically significant differences in transport rate constants were found between animals receiving 0 and 200 ppm supplemental dietary vanadium. The availability of a model will enable the refinement of future studies regarding vanadium metabolism in the ruminant.

Administration, Oral↗