Search PubMed⌕ Search

Biomedical subjects

D V Maurice

Publications and source records attributed to D V Maurice.

32 records · Page 2Linked to original sources

Ability of cimetidine to increase intestinal pH of chicks.

Cimetidine was tested for its ability to increase the pH of intestinal contents of chicks. In Experiment 1, 18 mg cimetidine injected i.m. per kilogram body weight (BW) increased (P less than .05) proventricular pH within 1 hr, but proventricular pH began to decrease 4 hr postinjection. The pH of the contents of the duodenum was increased (P less than .05) 4 hr postinjection, whereas the pH of the contents of the jejunum was unaffected. In Experiment 2, 36 mg cimetidine injected i.m. per kilogram BW increased (P less than .05) the pH of the contents in the proventriculus and duodenum, but did not alter the pH in the jejunum and ileum. These results show that cimetidine can be used for experimental purposes to increase the pH of the proventricular and duodenal contents in chickens.

Animals↗

Vitamin B12 nutriture of chickens fed raw soybean meal.

Experiments were conducted to investigate a possible interference by raw soybean meal (RSM) with B12 nutriture of chickens. In Experiment 1, day-old chicks were fed B12-free isonitrogenous and equienergetic diets containing 0 or 40% RSM to determine if RSM accelerated storage losses of B12. After 42 days, RSM decreased growth (P less than .01), decreased hepatic (P less than .01) and blood (P less than .05) concentrations of glutathione (GSH), and increased (P less than .01) pancreas and liver weights. However, statistically significant differences due to treatment were not detected in hepatic B12 concentration, indicating that RSM does not enhance B12 turnover in chicks. To ascertain the effect of RSM on B12 absorption, 9 micrograms B12/kg diet was added to diets containing 0 or 40% RSM and fed to chicks to 42 days of age. Raw soybean meal depressed growth (P less than .001) and hepatic GSH (P less than .01) and increased (P less than .001) pancreas weights. The RSM had no effect on hepatic B12 concentration, suggesting that RSM trypsin inhibition does not impair B12 absorption in chicks. A third experiment was designed to test the hypothesis that vitamin B12 stimulates egg production or feed intake of hens fed a diet with 27% RSM. Vitamin B12-depleted hens were fed RSM or heat-treated soybean meal (HSM) diets containing equivalent amounts of soybean protein, oil, and hulls. Hens received either 26 micrograms B12/kg BW per os or 13 micrograms B12/kg BW intramuscularly twice within a 30-day period.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

Metabolic effects of low aflatoxin B1 levels on broiler chicks.

The effects of daily ingestion of aflatoxin B1 (AFB1) on growth, feed intake, plasma glucose, plasma cholesterol, plasma amino acids, plasma albumin, plasma ceruloplasmin, muscle amino acids, liver lipid, and bone strength were studied. For 3 weeks, beginning at an age of 2 days, broiler chicks were dosed daily per os with 50 or 100 micrograms of AFB1 per kg of body weight. Body weight and feed consumption were recorded daily, and metabolic responses were determined at 3 weeks. Treatment with AFB1 did not significantly alter body weight or feed intake. Relative liver weight showed a significant increase at the highest dose, with a significant concomitant increase in liver lipid and decrease in hepatic zinc. Relative spleen and heart weights were not affected by the toxin. Plasma glucose and cholesterol were significantly elevated at the highest dose. AFB1 significantly decreased plasma lysine and histidine and significantly increased muscle histidine, arginine, and valine. AFB1 decreased plasma albumin and markedly increased plasma ceruloplasmin. Dimensions of the long bones (femur and tibiotarsus) were not altered by the toxin. However, AFB1 caused a significant linear decline in the resistance of bone to breakage ("bone breaking strength"). The results indicate that low levels of AFB1 reduced bone strength in broiler chicks. The alterations in blood parameters indicated that AFB1 can disrupt metabolism even at low levels.

Aflatoxin B1↗

Response of early weaned rabbits to source and level of dietary fiber.

Growth, cecal volatile fatty acids, mineral profile of plasma, liver weight and gastrointestinal weights were measured in rabbits fed isonitrogenous, equicaloric diets containing 3, 6, 9 or 12% dietary crude fiber from either alfalfa or Coastal Bermuda grass. Rabbits were fed from 4 to 8 wk of age. Alfalfa diets improved (P less than .05) average daily gain (20.5 vs 11.9 g/d) and livability (67.5 vs 42.5%). Feed intake, average daily gain and livability increased linearly with increasing fiber content within the alfalfa diets only. Source of fiber had no effect on total or individual cecal volatile fatty acids, except for an increased proportion of isobutyrate in rabbits fed Coastal Bermuda grass. Increased fiber level did not affect total volatile fatty acids, but did increase the proportion of butyrate and the butyrate:propionate ratio for both sources. Decreased propionate and valerate proportions were observed in cecal contents of rabbits fed Coastal Bermuda grass. Increased fiber levels decreased cecal pH in Coastal Bermuda grass-fed, but not alfalfa-fed rabbits. Relative cecal weights decreased as fiber levels increased for both sources. Coastal Bermuda grass diets resulted in larger stomach weights. Neither dietary fiber source nor level caused a consistent alteration in plasma mineral profile. The butyrate:propionate ratio reflected to a greater extent the value of feeds in fattening rabbits than did the acetate:propionate ratio normally calculated for ruminants and horses. It is concluded that the growing rabbit requires greater than 9% dietary crude fiber and that Coastal Bermuda grass is not a suitable source of fiber.

Animals↗

The effect of reverse protein and low protein feeding regimens in the rearing period on pullet growth, subsequent performance, and liver and abdominal fat at end of lay.

Four brown egg strains were used to study the effect of rearing diets on growth and performance. The treatments were arranged in a 4 x 3 factorial with two replicates of 45 birds. The control diet was formulated and fed to National Research Council recommendations. Birds on reverse protein (RP) were fed diets with 13, 16, and 19% protein and those on low protein (LP) regimen received a 13.5% protein diet with amino acids adjusted on a megacalorie basis to approximate the control diet. At 20 weeks of age pullets were caged and fed a standard layer diet. Logistic curves were fitted to the growth data by a nonlinear least squares method and the parameters of each curve analyzed. No significant strain x diet interactions were observed. There were significant differences among strains in weight gain and feed intake. Dietary regimens had no significant effect on total gain and feed intake. However, diets significantly altered age at one-half maximum growth or inflection point (alpha) and mean growth rate (rho). Inflection point of the growth curve was significantly delayed in birds fed RP and LP diets. Although apparent conversion was not affected by diets, the partition coefficients at any time (t) for maintenance (beta mt) and gain (beta gt) were altered. Neither strain nor dietary regimens affected abdominal fat or organ weights at the end of the rearing period. No significant effect of rearing dietary regimens was detected in age at 50% production or peak production, feed conversion, feed intake, livability, liver fat, abdominal fat, or shell strength. The reverse-protein regimen significantly depressed egg weight. The results of the study indicate that 1) the rearing dietary regimens were adequate for strains of different body weight and egg output characteristics; 2) dietary alteration of growth curve parameters failed to influence production, feed intake, mortality, shell strength, livability, liver fat, or abdominal fat during the production period.

Abdomen↗

Hepatic lipid metabolism in domestic fowl as influenced by dietary cereal.

The influence of dietary cereal on hepatic lipid metabolism was studied in adult Japanese quail and mature female chickens fed isoenergetic and isonitrogenous corn-soy and wheat-soy diets ad libitum. Hepatic lipid accumulation and rate of biosynthesis were significantly higher in birds fed the corn-soy diet. The differential response to the cereals was seen in ovipositing females but not in mature male quail. There were no significant concomitant changes in body composition, egg production, egg weight, body weight, feed, and energy intake. Results of sequential changes in hepatic lipid metabolism showed that reduction in liver fat was significant 2 to 3 weeks after feeding the wheat diet and was due to a significant reduction in rate of lipogenesis and the amount of triacylglycerols deposited. Plasma levels of free fatty acids and glucose were not significantly altered by the dietary regimes in laying hens. In Japanese quail fed the corn-soy diet, plasma glucose was elevated and there was evidence of impaired glucose tolerance. In vitro rate of oxidation of labeled palmitate was significantly higher in liver homogenates from birds fed the corn-soy diet. Addition of carnitine to the incubation mixtures resulted in an increase of equivalent magnitude for both treatments. Liver hemorrhages were observed in laying hens but not in Japanese quail. Addition of myo-inositol to the corn diet for Japanese quail failed to significantly alter hepatic lipid accumulation. These studies show that differences in liver lipid accumulation due to corn and wheat diets are related to changes in rate of lipogenesis.

Animals↗

Reduction of hepatic lipid deposition in laying hens by dietary selenium-yeast interaction.

Experiments were conducted to study the effect of chromiun and selenium on liver lipid deposition and incidence of liver hemorrhage in caged layers. Commercial strains of layers were fed ad libitum equicaloric and isonitrogenous diets. Corn-torula dried yeast diets containing added selenium (.1 microgram/g) with or without supplementary chromium (10 microgram/g) significantly reduced total liver lipid and liver hemorrhage. The effects of protein source (soybean meal vs. yeast) and selenium were separated in a factorial experiment which showed that the hepatic lipid response to selenium results from an interaction of selenium with an unidentified factor in torula yeast. The addition of selenium to diets with each protein source significantly elevated glutathione peroxidase (GSHPx) activity. Inclusion of 5% brewers yeast in the corn-soy diet or vitamin E (50 IU/kg) to the corn-torula dried yeast reduced liver lipid similar to that seen in birds fed the torula-yeast diet containing .1 microgram Se/g. Comparison of oral glucose tolerance of birds fed corn-soy and corn-soy brewers yeast diets showed no significant difference. None of the dietary treatments significantly altered body weight, egg production, egg weight, or feed consumption. The results indicate that the metabolic role of selenium in relation to its role in hepatic lipid metabolism is mediated through an interaction with a dietary factor(s) present in yeast.

Animal Feed↗

Effect of dietary cereal on liver and plasma lipids in laying Japanese quail.

1. In three experiments the effect of diets containing maize or wheat on hepatic and plasma lipids in laying japanese quail were studied. In two of these diets of equal energy, nitrogen and fat contents were used. 2. Liver weight, relative to body weight, liver lipid content and plasma lipid concentration were greater in birds fed on maize-containing diets. 3. The maize-containing diet also produced more (14 : 0, 16 : 0, 16 : 1 and 18 : 1) and less (18 : 0, 18 : 2 and 20 :4) fatty acids in the liver lipid. 4. Egg production was not affected by the treatments. 5. The effect of dietary cereal on hepatic and plasma lipids may be due to altered lipogenesis and the quail may be a useful model for the laying hen with respect to hepatic lipid accumulation.

Animals↗

Effect of high dietary copper on the ceca of chicks.

Including 120 to 250 mg./kg. additional copper in practical broiler rations significantly affected the cecal appearance. The ceca were distended and the contents were darker in color and more pasty in consistency, compared to controls. Adding monensin sodium, gentian violet, or ferrous sulfate alone or in combination with copper to the ration did not significantly change the appearance of the ceca. Copper concentrations in the cecal contents reached levels above 5000 mg./kg., suggesting that the mechanism of action of copper in changing the appearance of the ceca may be related to an inhibition of normal fermentation that occurs in this part of the gastrointestinal tract. Sulfate, chloride and carbonate forms of copper all significantly changed cecal appearance, but the oxide did not, nor did a non-copper containing sulfate source. Macroscopic appearance of the gizzard lining and the proventriculus was also significantly changed by adding 240 mg./kg. copper to the diet, and liver weight and lipid content of liver dry matter were significantly increased.

Animals↗

Influence of diet composition on hepatic lipid accumulation and hemorrhages in caged layers.

Four experiments were conducted with commercial strains of White Leghorns. Experimental corn-soy diets with (CSW) and without (CS) minor feed ingredients significantly elevated liver and plasma lipids when compared to a standard layer diet (UGA) used at the University of Georgia. The response was not due to difference in vitamin and mineral premix or level of energy and protein in the diets. Inclusion of 5% alfalfa in a low protein (13.5%) diet with energy and amino acid profile similar to diet CS significantly reduced liver lipid. Comparison of diet CS to isocaloric and isonitrogenous diets with 20% brewers dried grains, soybean mill feed, or wheat bran showed that layers fed diets with these supplements had significantly lower liver and plasma lipids. In all experiments a higher incidence of liver hemorrhage was associated with feeding the experimental diets CS and CSW. There were no significant differences in egg production, egg weight, or body weight change due to dietary treatment in the experiments. Results of the experiments show that hens with equivalent ME intake and egg output exhibit differences in liver and plasma lipids due to diet composition. The data suggest that mill feeds and fermentation by-products contain an essential factor for control of lipid metabolism in caged layers.

Animal Feed↗

Effect of biotin and niacin on lipid content of livers in the laying hen.

Single Comb White Leghorn layers maintained in cages were fed a corn-soy diet with a simplified vitamin premix for a 12-week experimental period to determine the effect on liver lipid accumulation. Lipid content was only 29.6% of the liver dry matter and, therefore, was in the normal range and less than that seen in hens with fatty liver syndrome. Adding niacin (44 mg./kg.) or biotin (110 mug./kg.) either alone or in combination failed to significantly alter liver weight or liver lipid content. Liver lipid content of hens fed another diet with a more complex vitamin premix also was not significantly different from that of hens fed the diet with the simplified vitamin premix. None of the diets significantly affected egg production, egg weight, feed consumption or body weight changes observed over the 12-week period.

Animal Feed↗

Liver lipid accumulation and performance of hens as affected by cage density and initial body weight.

Hens housed in individual cages (25 46 cm.) laid significantly more eggs, consumed significantly more feed and had significantly larger livers with a higher lipid content than hens housed three to a cage in two experiments. Body weight gain was significantly higher for individually housed birds in experiment 1, but not in experiment 2. No difference was observed in mean egg weight or kg. feed per dozen eggs. In experiment 2 hens housed two to a cage laid slightly fewer eggs and accumulated slightly less liver fat but the differences were not significantly different fromthose housed individually. Hens socially dominant in three bird pens had higher liver fat accumulation than hens lower on the peck order but liver fat accumulation for the dominant hens still averaged less than hens housed either two or one per cage. Comparison of two strains in experiment 1 revealed a significant difference in rate of egg production and feed efficiency but no difference in liver fat accumulation. Pullets placed in four body weight classes prior to the start of the experiment did not differ significantly in liver fat accumulation per unit of body weight or percentof dry matter of the liver at the end of the experiment. Rate of egg production and feed efficiency were also not significantly different among the body weight classes.

Animals↗