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Biomedical subjects

R D Miles

Publications and source records attributed to R D Miles.

At least 73 records · Page 4Linked to original sources
PubMed1985

Plasma calcium, phosphorus, 25-dihydroxyvitamin D3, and 1-25-dihydroxyvitamin D3 of hens with fatty liver syndrome.

Plasma was obtained from normal laying hens, 30 weeks of age, and from laying hens, 60 weeks of age, with fatty liver syndrome (FLS). The 60-week-old hens were divided into two groups based on whether they were laying or nonlaying. Plasma phosphorus and calcium was significantly higher for hens with FLS. The younger hens had significantly lower 25-dihydroxyvitamin D3 (25-OH-D3) plasma levels than the older hens. The older hens that were laying had significantly lower 25-OH-D3 plasma levels than the nonlaying hens. Old nonlaying hens with FLS had lower 1, 25-OH-D3 than young hens or old laying hens with FLS; however, the levels were not different for the two groups of laying hens.

Animals↗
PubMed1985

Influence of virginiamycin on energy utilization when turkey poults were fed ad libitum or restricted.

An experiment was conducted with day-old turkey poults to study the influence of virginiamycin on energy utilization. A 2 X 2 factorial arrangement of treatments was used, which included ad libitum or a 25% feed restriction and 0 or 22 ppm of virginiamycin. Virginiamycin in the diet significantly improved body weight, feed efficiency, and dietary energy utilization when poults were fed ad libitum or when feed was restricted. These data indicate that virginiamycin enhances the utilization of dietary energy by turkey poults.

Animals↗
PubMed1984

Interrelationship between sodium chloride, sodium bicarbonate, calcium, and phosphorus in laying hen diets.

Three experiments were conducted with Hy-Line W-36 laying hens housed in individual wire cages in open type houses. The first and second experiments were designed to investigate the effects of sodium chloride and sodium bicarbonate fed at two levels of dietary total phosphorus (.30 and .60%). The third experiment was designed to study the interrelationships between age and sodium source. Supplementing sodium chloride at two levels (.37 and 1.11%) did not effect hen performance, except that egg production was better at the lower NaCl. Egg production was greater when .60 rather than .30% dietary phosphorus was fed. Egg specific gravity and egg weight were decreased at the lower dietary phosphorus. The addition of 1.6% sodium bicarbonate in the sodium chloride-free diets was deleterious to hen performance in all experiments. High mortality was observed in both experiments in which hens were fed diets containing high sodium and low chloride. Plasma calcium and phosphorus levels were significantly depressed in hens fed diets containing the lower phosphorus. Blood pH, base excess, bicarbonate, and total carbon dioxide were significantly increased by sodium bicarbonate supplementation, and these values were found to be inversely related to dietary phosphorus levels.

Animals↗
PubMed1984

Plasma phosphorus at 0, 6, and 21 hours postoviposition in hens laying in the morning or afternoon.

Two experiments were conducted using White Leghorn hens. Blood samples were collected immediately following oviposition (0 hr) or 6 or 21 hr postoviposition from hens laying in the morning or afternoon. Plasma phosphorus was determined at each time period. In Experiment 1, plasma phosphorus at oviposition was essentially the same for hens laying in the morning or afternoon (3.95 and 4.10 mg/dl, respectively). At 6 hr postoviposition plasma phosphorus was lower than that observed at 0 hr (3.22 and 3.15 mg/dl, respectively). When comparing plasma phosphorus levels at 21 hr postoviposition of hens laying in the morning or afternoon a higher (P less than or equal to .05) phosphorus level was observed for hens that laid in the morning (5.90 vs. 4.91, respectively). In Experiment 2, plasma phosphorus levels at 0 and 6 hr postoviposition were 3.32 vs. 3.18 and 2.81 vs. 2.74 mg/dl for hens laying in the morning and afternoon, respectively. At 21 hr postoviposition, phosphorus values of 5.30 vs. 3.65 mg/dl were reported for hens laying in the morning and afternoon, respectively. Data also indicated that on the day a hen does not lay an egg, plasma phosphorus does not rise. An hypothesis is offered to explain the difference in egg shell quality between eggs laid in the morning or afternoon.

Animals↗
PubMed1984

Virginiamycin and broiler performance.

Two experiments were conducted with broilers to determine the effect of Virginiamycin supplementation on performance and shank pigmentation. Virginiamycin supplementation at 10 ppm resulted in significantly increased body weights in both experiments. Feed efficiency was significantly improved in Experiment 1 by the supplementation of 5 and 10 ppm Virginiamycin. In Experiment 2, 20 ppm Virginiamycin was included and resulted in no greater response than that observed at 10 ppm. Pigmentation values as measured by a reflectance colorimeter and Roche color fan favored (P less than or equal to .05) Virginiamycin supplementation in both experiments. Data indicated that when the diet was supplemented with Virginiamycin an increase in the utilization of xanthophyll resulted. Mortality was not influenced by dietary treatment.

Animals↗
PubMed1984

Interrelationship between phosphorus, sodium, and chloride in the diet of laying hens.

Two experiments were conducted with commercial egg production type hens to determine the effects of dietary phosphorus, sodium, and chloride levels as related to levels of plasma calcium and phosphorus, blood acid-base balance, and production characteristics. Sodium and chloride were supplied to the diet as sodium bicarbonate and hydrochloric acid, respectively. In Experiment 1, five treatment groups were fed diets ad libitum containing .2, .6, 1.0, 1.4, and 1.8% total phosphorus. The remaining treatment group was fed a diet containing .4% total phosphorus from 1400 to 2030 hr and 1.4% total phosphorus from 600 to 1100 hr. In Experiment 2, a 3 X 4 factorial arrangement of treatments was used that consisted of three levels of total phosphorus (.2, .6, and 1.4%) and four levels of added sodium (0, .06, .22, and .45%) provided by sodium bicarbonate. Three other treatment groups were fed diets containing .36% supplemental chloride supplied by hydrochloric acid and either .2, .6, or 1.4% total phosphorus. Egg production was decreased in hens fed diets containing 1.8% total phosphorus. Egg specific gravity was decreased by both low and high phosphorus levels. Hens fed .4% total phosphorus in the afternoon produced eggs with higher specific gravity as compared with hens fed 1.4% total phosphorus during the entire experiment. At 1.4% dietary phosphorus, a significant increase in specific gravity was observed when .2 or .8% sodium bicarbonate was added to the diet. Increasing dietary phosphorus resulted in elevated plasma phosphorus and calcium concentration. Plasma phosphorus of hens fed .2 through 1.8% total phosphorus declined slowly from oviposition until 6 hr after oviposition and then reached a peak at 21 hr after oviposition.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1984

Effects of supplemental methionine and potassium sulfate on the choline requirement of the turkey poult.

Two experiments were conducted to study the relationship of methionine and potassium sulfate (K2SO4) on the choline requirement of turkey poults from hatch to three weeks of age. A corn-soybean meal basal diet was used which contained no supplemental choline or methionine. Also sulfate-free trace minerals were used. In Experiment 1, a linear increase in body weight was obtained by adding supplemental choline up to 660 mg/kg when the diet did not contain supplemental methionine. No response was obtained from supplemental choline when the diet contained a level higher than required for methionine (.25%). Feed efficiency was not affected by supplemental choline regardless of the level of supplemental methionine. In Experiment 2, a linear response in body weight was obtained by adding supplemental choline up to 1100 mg/kg diet in the presence or absence of supplemental K2SO4. The addition of K2SO4 to the diet did not significantly increase body weight at any level of supplemental choline. However, when all levels of choline were combined, the addition of K2SO4 significantly increased body weight, which indicated that the response from the two supplements were additive.

Animals↗
PubMed1984

Biological availability of manganese sources and effects of high dietary manganese on tissue mineral composition of broiler-type chicks.

An experiment was conducted with male broiler-type chicks to study tissue uptake of Mn as a measure of biological availability of Mn sources. A basal corn-soybean meal diet (116 ppm Mn) was supplemented with 0, 1000, 2000, or 4000 ppm Mn as either reagent grade sulfate, carbonate, or monoxide and fed ad libitum for 26 days. No toxic effects were noted as expressed by feed intake, weight gain, feed conversion, hematocrit, hemoglobin, or mortality. Analysis of Mn in tissues revealed a highly linear relationship between liver or bone Mn concentration and dietary Mn for all three sources. Manganese concentration in all tissues increased (P less than .01) as dietary Mn increased. Liver and bone Mn accumulation appeared to be excellent indicators of relative biological availability. On the basis of tissue uptake and solubility tests, MnSO4 X H2O was the most available, followed by MnO and MnCO3, respectively. There were no effects of Mn source or level on concentration of Ca, P, Mg, Cu, Zn, or Fe in tissues studied.

Animals↗
PubMed1983

The interrelationships between methionine, choline, and sulfate in turkey diets.

Two experiments were conducted with turkey poults to determine the interrelationship of choline, sulfate, and methionine. The addition of choline significantly increased growth and the addition of sulfate resulted in numerically improved growth. However, when the two were added in combination a further improvement in growth was obtained, indicating that both nutrients must be in the feed for maximum utilization of the other. These data also indicate that a complete understanding of the interrelationships between methionine-choline and methionine-sulfate cannot be accomplished unless all three are studied simultaneously.

Amino Acids, Sulfur↗
PubMed1983

The interrelationship between methionine, choline, and sulfate in broiler diets.

Two experiments were conducted to study the interrelationships between methionine, choline, and inorganic sulfate in a corn-soybean meal diet. The basal diet contained 21% crude protein and 3264 kcal ME/kg and no supplemental methionine, choline, or potassium sulfate. A 2 X 2 X 2 factorial arrangement of treatments was used involving .24% DL-methionine, 1100 mg choline/kg, and .10% potassium sulfate. A total of 384 Cobb, male, feather-sexed chicks were fed the experimental diets for 3 weeks in each experiment. Supplementing the basal diet with potassium sulfate in the presence of choline or methionine resulted in a greater growth response than when either was supplemented alone. A consistent sulfate response occurred when the diet contained supplemental choline and no supplemental methionine. Results indicated that sulfate must be present for choline to spare a maximum amount of methionine.

Animals↗
PubMed1983

A comparison of DL-methionine and Liquimeth as a source of supplemental methionine for the turkey poult.

Two experiments were conducted to determine the efficacy of DL-methionine and DL-methionine-Na (Liquimeth) as a source of methionine for the turkey poult. A corn-soybean meal diet containing sulfate-free trace minerals and no supplemental choline was used. In two experiments the poults were fed the experimental diets from 1 to 21 days of age. The experimental diets and deionized water were offered ad libitum. A linear increase in growth was obtained by adding increments of either DL-methionine or Liquimeth. There were no significant differences in body weight of poults receiving equivalent amounts of methionine from the two sources. Feed efficiency was also equal for each level of supplemental methionine from the two sources.

Animals↗
PubMed1983

Choline supplementation in the diets of aged White Leghorn hens grouped according to body weight.

A randomized block design experiment was conducted to determine if aged layers require supplemental choline when fed practical corn-soy diets adequate in methionine. Hisex hens (50 weeks old) were divided into four body weight groups containing 120 hens each. Six experimental treatments were prepared by addition of choline to a corn-soy basal diet at 0, 55, 110, 220, 440, and 880 mg/kg of diet. Each diet was fed to four replicates of 5 hens each within each body weight group. The nutrient content in the basal diet formulated for each body weight group was adjusted depending on daily feed intake. The experiment was conducted for four 28-day periods (January 21 to May 13). Hen-day egg production, feed conversion, egg specific gravity, and egg weight did not differ significantly for any level of choline supplementation. Liver lipid content was significantly different at no supplemental choline in extra heavy birds. Results of this experiment support the conclusion that, regardless of body weight, aged laying hens required very little, if any, supplemental choline when they are fed a corn-soy practical diet containing adequate methionine.

Animals↗
PubMed1983

The influence of dietary phosphorus level on laying hen performance, egg shell quality, and various blood parameters.

The influence of dietary phosphorus on hen performance and egg shell quality was investigated. Total dietary phosphorus levels of .17, .23, .30, .40, .50, .70, 1.50, and 2.30% were fed to four body weight groups of 23-week-old White Leghorn hens. Hens consuming the diets containing .17, .23, and .30% phosphorus, all from plant origin, consumed significantly (P less than or equal to .05) less feed, which resulted in poorer performance than hens fed diets supplemented with inorganic phosphorus. Addition of supplemental inorganic phosphorus at levels of .10 to .40% resulted in the best overall hen performance. Plasma phosphorus was directly related to dietary phosphorus level. Egg shell quality as measured by specific gravity was inversely related to dietary phosphorus levels above .50%.

Animals↗
PubMed1983

The response of turkey poults to virginiamycin in diets containing various levels of supplemental methionine.

Two experiments were conducted with day-old Nicholas Large White turkey poults. A 2 x 3 factorial arrangement of treatments was used in Experiment 1 (0 and 22 ppm of virginiamycin and 0, .06, and .12% supplemental DL-methionine). A 2 x 4 factorial arrangement of treatments was used in Experiment 2 (0 and 22 ppm of virginiamycin and 0, .04, .08, and .12% DL-methionine). A corn-soybean meal diet was used that contained no supplemental choline and a sulfate-free trace mineral mix. The experiments were conducted for 21 days. Body weight was increased by virginiamycin and by all levels of supplemental methionine. However, feed efficiency was not influenced.

Animals↗
PubMed1983

Computerized multiplanar imaging and lumen area plotting for noninvasive diagnosis of carotid artery disease.

Some of the errors associated with pulsed Doppler imaging of the carotid bifurcation relate to the fact that the vessels are usually viewed in only one plane. To reduce these projection errors, a computerized ultrasonic arteriograph (CUA) was developed, which simultaneously produces lateral and anteroposterior images of the carotid bifurcation together with a histogram that depicts the cross-sectional area of the lumen at 1 mm points along the vessel. The area measured from the histogram and that estimated from biplanar arteriograms agreed in 46/57 (81%) of the internal carotid arteries studied by both techniques. The area histogram was positive for 91% of the arteries with arteriographically visible disease and was 79% specific for eliminating the presence of disease. The combined CUA study (histogram plus images) had a sensitivity and specificity of 96% and 80% for detecting any disease, 96% and 92% for evaluating diameter stenoses of 20%, and 89% and 98% or evaluating stenoses of 40%. These preliminary results suggest that the CUA may enhance the accuracy of pulsed Doppler imaging.

Carotid Artery Diseases↗
PubMed1982

Cyclic changes in plasma phosphorus of laying turkeys.

Plasma phosphorus of laying turkeys measured at 0, 6, 18, and 24 hr after oviposition showed a cyclic pattern similar to that reported for laying chickens. Plasma phosphorus was lowest at oviposition and remained relatively low until 6 hr postoviposition; values at 18 and 24 hr postoviposition were higher. Plasma phosphorus was higher (P less than .05) 24 hr postoviposition than 0 or 6 hr postoviposition. The changes were assumed to be associated with egg shell calcification and bone resorption. Plasma phosphorus values of turkey toms measured during a 24-hr period remained constant and were not significantly (P less than .05) different from each other.

Animals↗
PubMed1982

Influence of Protamone on fatty liver syndrome in commercial laying hens.

Two experiments were conducted to determine the influence of Protamone on fatty liver syndrome in commercial laying hens. The addition of either 110 or 220 mg of protamone per kilogram of diet significantly lowered liver fat and also significantly reduced body weight. From histological examination of livers of hens fed Protamone it was found that the hepatocytes contained little or no lipid, whereas hepatocytes of hens fed the control diet were turgid with lipid. The addition of Protamone to the diet resulted in a significant reduction in egg production without effecting feed efficiency in Experiment 1. In Experiment 2, egg production was significantly reduced and feed efficiency improved during Days 1 to 28. However, feed efficiency was poorer during Days 29 to 56 for hens receiving the Protamone.

Animals↗