Biomedical subjects

H M Cervantes

Publications and source records attributed to H M Cervantes.

5 recordsLinked to original sources

PubMed1990

Dietary and monensin effects on activity of hepatic microsomal mixed function oxidase system in chickens.

Four experiments were conducted to investigate if the degree of activation of the microsomal mixed-function oxidase (MFO) system was related to the degree of growth depression associated with the addition of monensin to the diet. The experiments were conducted with broiler chicks in battery brooders in which the chicks were fed diets of various composition and containing monensin at 0 to 160 ppm. In all experiments, the activity of the MFO system was estimated by the change in the content of cytochrome P-450 in the hepatic microsomes. Activities of some microsomal enzymes were also measured in some of the experiments. Feeding a diet with 24% protein containing fish meal, alfalfa meal, and torula yeast significantly increased the activity of the MFO system in comparison with feeding an isonitrogenous and isoenergetic corn and soybean diet, but there was no difference between the diets in the toxicity of monensin as measured by growth rate. Supplementing a 16% protein but not a 24% protein diet with monensin significantly reduced growth rate. In none of the four experiments was there a statistically significant change in the hepatic content of cytochrome P-450 as a result of feeding monensin. Thus, variation in the magnitude of growth depression caused by monensin in diets of different protein concentration or ingredient composition does not appear to be explained on the relative degree of the activation of the MFO system.

Animal Feed↗

PubMed1986

Interaction of monensin with dietary vanadium, potassium, and protein, and its effect on hepatic rubidium and potassium in chicks.

A series of experiments was undertaken to further investigate the influence of diet composition on chick response to monensin supplementation. Experiments were conducted to determine the effect of monensin on growth rate and hepatic Rb and K content as affected by dietary content of V, K, or protein. A factorial experiment involving V levels of 0, 5, 10, or 20 ppm and monensin levels of 0, 120, or 160 ppm was conducted with broiler chicks to 4 weeks of age. Growth rate was significantly depressed by 10 or 20 ppm V but not by monensin. Hepatic K content was not affected by dietary treatments. In another factorial experiment, effects of levels of 0 and 120 ppm monensin and 0 and 5 ppm V were compared. Growth rate was significantly depressed by both V and monensin but with no significant interaction. Neither hepatic Rb or K content was significantly altered by the supplements. A third factorial experiment involved monensin levels of 0, 120, or 160 ppm, added K levels of 0 or .3%, and dietary protein levels of 16 or 24%. Body weight at 3 weeks of age was significantly depressed by 160 ppm monensin in the high protein diet and by 120 or 160 ppm in the low protein diet. Added K did not counteract the growth depression. Hepatic Rb content was increased by monensin and significantly reduced by K supplementation. Hepatic K content was not increased by K supplementation. Chicks fed the low protein diet had significantly lower concentrations of hepatic Rb and K than those fed the high protein diet.

Animals↗

PubMed1985

Activation of hepatic microsomal mixed function oxidase system in broiler chicks by diet changes.

Two experiments were conducted to investigate the effect of diet composition on activity of the microsomal mixed function oxidase (MFO) system in broiler chicks. One-day-old chicks were fed for 10 days either a corn-soy (CS) diet or diets supplemented with a combination of fish meal, alfalfa meal, and torula yeast (FAY) or individually with fish meal (FM), alfalfa meal, distillers dried grains with solubles (DDGS), or torula yeast (TY). Activities of hepatic microsomal aniline hydroxylase and aminopyrine N-demethylase were increased when chicks were fed FAY, FM, TY, or DDGS compared with those fed CS. In another experiment chicks were fed the CS and FAY diets to 4 weeks of age. Hepatic microsomal cytochrome P-450, cytochrome b5, and activities of aniline hydroxylase and aminopyrine N-demethylase were significantly increased in birds fed the FAY diet. Activities of NADPH and NADH-cytochrome C reductase were not affected. These results show that the hepatic microsomal MFO system is activated by changes in diet composition and suggest that this activation may be responsible for reducing estradiol and liver lipid levels when similar diets are fed to laying hens.

Aminopyrine N-Demethylase↗

PubMed1984

Liver lipid content in broilers as affected by time without feed or feed and water.

The purpose of this study was to determine if length of time of feed withdrawal of broilers prior to slaughter could affect the lipid content of their livers. Seven-week-old male broilers were allocated to three treatments: 1) no feed and water, 2) no feed, and 3) feed and water ad libitum. Those in the first treatment were held in plastic coops and those in the latter two treatments were kept in floor pens. Eight birds were randomly sampled initially and eight birds from each treatment at 4, 8, 12, 16, and 24 hr after the start of the study. The birds were weighed, killed, and the livers removed and analyzed for lipid content. The regression slopes of the two treatments without feed for body weight, liver weight, liver weight per unit body weight, and liver fat per unit body weight were significantly different from the control treatment. The slopes for liver fat were not significantly different among treatments. No obvious differences in the gross appearance of the livers were detected. The occasional problems with fatty livers in commercial broilers apparently cannot be accounted for by the length of time of feed withdrawal before slaughter.

Animals↗

PubMedDate not supplied

Staphylococcus-induced gangrenous dermatitis in broilers.

An infectious bursal disease (IBD)-vaccinated flock of 23,900 broilers, 17 days of age, experienced sudden onset of depression, dermatitis, and mortality. Postmortem examination showed extensive subcutaneous serosanguineous fluid accumulation over the pectoral muscles, discrete hepatic whitish foci, fluid-filled intestines, and small, flaccid bursae of Fabricius. Gram-stained impression smears from the affected areas revealed numerous gram-positive cocci. Aerobic culture of liver and subcutaneous tissue consistently produced heavy growth of penicillin-sensitive Staphyloccus aureus. Histopathologically, subcutaneous tissue showed diffuse hemorrhage and large numbers of gram-positive cocci with severe congestion and hemorrhage of the underlying skeletal muscle. Liver sections showed multiple, randomly scattered areas of acute coagulation necrosis with numerous gram-positive cocci. Bursal lesions were characterized by extensive follicular necrosis and collapse. A diagnosis of staphylococcal gangrenous dermatitis secondary to IBD was made. Mortality returned to preinfection levels within 72 hours after penicillin was added to the drinking water.

Animals↗