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Biomedical subjects

M E Cook

Publications and source records attributed to M E Cook.

At least 91 records · Page 5Linked to original sources
PubMed1987

Lighting and sex ratio for breeding ringnecked pheasants in confined housing.

In two trials with breeding pheasants, pheasants were assigned to two male:female sex ratios (1:12 and 1:18) arranged factorially with two lighting regimens (14 or 16 hr of light) in a 24-hr period. In each trial, 1644 or 1680 pheasant hens divided in two replicates were assigned to each experimental treatment and placed in controlled environment housing. Hen mortality, percent culled eggs, total eggs per hen-housed, fertility, hatchability, and usable chicks per hen-housed were determined over a 9-week production period. Although mortality and percent hatch were not affected by either sex ratio or lighting, percent culled eggs increased with increased light (16 hr light) and usable chicks per hen-housed decreased with increased light. Increasing the sex ratio from 1:12 to 1:18 increased egg production but decreased fertility. These data demonstrate that pheasants reared in a controlled environment require less than 16 hr light for maximizing usable chick production per hen-housed and there is a trade-off between fertility and egg production.

Animals↗
PubMed1987

Efficacy of cysteine in replacing methionine in the immune responses of broiler chicks.

Two trials were conducted to compare the effects of supplements of methionine and cysteine on the growth and immune responses of broiler chicks fed corn-soy diets. The basal diet contained 21% crude protein, 3,255 kcal metabolizable energy/kg diet, .35% methionine, .37% cysteine, and .13% choline. Additions to the basal diet were methionine (.063, .25, .85, and 1.45%), or cysteine (.203%), or a combination of methionine (.063%) and cysteine (.153%). Total antibody and 2-mercaptoethanol-resistant antibodies, immunoglobulin G (IgG), were determined in chicks inoculated intraperitoneally at 14 days of age and serially bled at 4, 7, and 10 days postinoculation. Thymus-derived (T)-cell-dependent in vivo mitogen response to phytohemagglutinin-P (PHA-P) was assessed via wing web swelling. The methionine requirement for growth (0 to 3 wk of age) was found to be no more than .413% of the diet (.35% in the basal diet plus .063% added). Addition of 1.45% methionine to the basal diet resulted in significant depression (P less than .05) in growth. The antibody responses generally peaked at 7 days postprimary inoculation. Both methionine and cystine supplementation at low levels resulted in improvement in the cell mediated PHA-P responses as well as in the IgG (T-cell-dependent) responses. High supplemental methionine (1.45%), however, caused significant (P less than .05) depressions in both responses. Equimolar additions of methionine and cysteine (16.8 mmol/kg diet) showed that cysteine was about 84 and 70% as efficacious as methionine in the IgG and the PHA-P stimulation (PHA-I), respectively, in healthy chicks.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Enhanced immune responses in broiler chicks fed methionine-supplemented diets.

Effects of feeding supplementary methionine and choline on broiler growth and immunity were examined by supplementing a corn-soybean diet that contained 21% crude protein, 3,255 kcal metabolizable energy/kg diet, .35% methionine, .37% cystine, and .13% choline. Methionine (.063, .125, .25%) and choline (.125, .25%) were dietary variables. Sulfate (.055%) was added either alone or along with methionine (.125 or .25%) and choline (.125%). In one study, the .25% methionine diet was supplemented with .121% betaine. Sodium and chloride levels were constant in all the diets. Feed and distilled water were supplied ad libitum. Total antibodies, immunoglobulin (Ig) G (2-mercaptoethanol-resistant antibodies) and IgM (2-mercaptoethanol-sensitive antibodies) were determined in 3-wk-old chicks inoculated intraperitoneally with sheep red blood cells. The thymus-derived (T)-cell-dependent in vivo mitogen response to phytohemagglutinin-P (PHA-P) was assessed via wing web swelling. The methionine requirement for growth (0 to 3 wk of age) was approximately .413% of the diet (.35% in the basal diet plus .063% added). Supplementation of the basal diet with .125% choline stimulated growth to the same extent as did the extra .063% of methionine. Addition of .055% sulfate with .125% choline did not improve the ability of the latter to spare methionine. Supplemental methionine resulted in significant (P less than .05) dose-related increases in total antibody, IgG, and response to the mitogen PHA-P, but not in IgM. There were no effects of choline on the immune variables studied. These results suggest that methionine is required for select components of the antibody response, which effect might be related to T-cell help.

Animals↗
PubMed1987

Assessment of softness properties of feathers.

An instrument to be called the "Crimp Meter" was designed and used with a conventional balance to enable the plotting of a force-displacement curve for individual feathers. A comparison of the curves described by different feathers was made by regression analysis. The type of curve described by a feather is characteristic of its tensile properties and its degree of softness. This procedure was employed to objectively confirm the observation that chicks fed toxic levels of methionine (1.45% added) in corn-soybean diets had significantly softer (P less than .001) feathers than those fed nontoxic levels of cysteine (.203% added). The basal diet was analyzed and found to contain .35% methionine and .37% cystine. This device had potential for the down-feather, wool, and fabric industries.

Animals↗
PubMed1987

Critical vitamin supplementation of broiler diets high in alfalfa juice protein.

Three trials were conducted to identify the critical vitamins in the diets of broiler-strain chicks fed alfalfa juice protein concentrate (AJPC) corn-soy diets from 0 to 3 wk of age. Vitamin supplements were added to AJPC diets. Diets were formulated to contain, parts 30/121, 40/128, 50/135, and 60/142 parts AJPC/parts total diet. Parts were used to permit usage of wet materials and still maintain about 90% dry matter. All diets were formulated to contain 20% crude protein, .93% total sulfur-containing amino acids, and 2,940 kcal metabolizable energy/kg diet. Propionic acid was added at .2% to all diets. Feeds were refrigerated (7 C) and fed out daily. The addition of choline, riboflavin, vitamin B12, vitamin A or E, folic acid, or biotin did not increase weight gains. Addition of 3 mg/kg vitamin B6 completely overcame the growth depression caused by the 50-parts AJPC diet and significant (P less than .05) growth increases (13 to 29%) were achieved with vitamin-B6 supplementation to the 60-parts AJPC diet. Depressed immune responses were completely prevented by the addition of 3 mg/kg of vitamin B6. The significant (P less than .05) increases in leg deformities observed in birds fed the 60-parts AJPC diet were also brought back to more typical values in birds fed the diet supplemented with 3 mg/kg vitamin B6. Vitamin K supplementation (.53 mg/kg) to the 60-parts AJPC diet resulted in significant decreases from 15 min in blood clotting times to 3 to 5 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1987

Suppressed humoral immunity in chicks fed diets deficient in sodium, chloride, or both sodium and chloride.

Four experiments were conducted to determine the effect of Na and Cl on the antibody response to sheep red blood cells (SRBC). In the first two experiments, Na and Cl were supplemented in the diet together as NaCl at levels from 0 to .75%. In two additional experiments, Na and Cl were supplemented independently; levels varied from .04 to .24% total dietary Na and from .07 to .36% total dietary Cl. Results of the first two experiments indicated that dietary Na and Cl levels above that found in a corn-soybean diet improved the antibody response to SRBC. Additional studies showed that the humoral immunity was significantly suppressed when chicks consumed diets with less than .14% Na and .17% Cl. Increasing dietary Cl from .17 to .27% when dietary Na was .04% suppressed the antibody response. Also, increasing dietary Cl from .21 to .36% when dietary Na was .14 or .24% suppressed the antibody response. The immunosuppression of the humoral response of chicks was determined to be not related to the decreased feed intake resulting from inadequate Na and Cl in the diet.

Animals↗
PubMed1986

Excessive cholecalciferol in a layers diet: decline in some aspects of reproductive performance and increased bone mineralisation of progeny.

Feeding hens a diet containing 5,000 micrograms (200,000 ICU)/kg of cholecalciferol for four 28-d periods had no adverse effect on hen-day egg production or hatchability. Egg weight, shell quality, food consumption and fertility were significantly decreased in hens fed 5,000 micrograms/kg. of cholecalciferol compared with those fed 24 micrograms (960 ICU) cholecalciferol/kg diet. Plasma calcium increased significantly as the concentration of cholecalciferol was increased in the diet. However, no histologically detectable changes in the viscera or changes in the proportion of bone ash were observed with any concentration of the vitamin. Chicks hatched from dams receiving excessive doses of cholecalciferol (5,000 micrograms/kg) and maintained on a rachitogenic diet for 4 weeks had a significantly higher proportion of tibial ash but there was no effect on either body weight or tibial calcium.

Animals↗
PubMed1986

Effect of nutritional status, age at weaning and room temperature on growth and systemic immune response of weanling pigs.

Two experiments were conducted to determine the effect of nutritional status, age at weaning and room temperature on growth and immune response of pigs. In the first experiment, 72 pigs were weaned at either 2 or 3 wk and fed either a complex, simple-adequate or simple-inadequate diet for a 24-d period. Total antibody (TAb) titers in response to injections of human red blood cells (RBC) on either 0, 4, or 16 d postweaning were not affected by age at weaning or dietary treatments even though the nutritional status was compromised to such an extent that pigs fed the simple-adequate diet gained at one-half the rate (.172 vs .349 kg/d) of pigs fed the complex or simple-adequate diets (P less than .01). In Exp. 2, the immunological response of 144 pigs weaned at 3 wk were evaluated at 4 and 8 d postweaning. Pigs were weaned into rooms that averaged either 25 or 18 C, and were fed either a complex or simplex-adequate diet at either ad libitum (AL) or restricted (Res) levels for a 24-d period. Restriction of either the complex or simple diet for the first 16 d of the trial drastically reduced (P less than .01) the growth rates of Res pigs compared with AL pigs (.042 vs .236 kg/d). There were no differences in skinfold thickness (Sf) or TAb, 2-mercaptoethanol sensitive (MEs) and resistant (MEr) antibody titers when pigs were inoculated with phytohemagglutinin-P (PHA-P) or RBC at 4 d postweaning regardless of room temperature, diet source or feeding level.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1986

Mechanical properties of the tibiotarsus of broilers and poults loaded with artificial weight and fed various dietary protein levels.

Bone strength comparisons were made on tibiotarsi of chicks and poults fed various levels of dietary protein and either loaded or not loaded with artificial weights. Stress and modulus of elasticity were evaluated for their ability to measure strength and rigidity differences in bones while accounting for various bone size. Often comparisons between birds of different ages and body weights are attempted despite various bone size and dimension. These terms identified the weaker, less rigid bones in a comparison between chicks fed a low calcium, low phosphorus diet and a control group matched for age, weight, and bone size. Stress values were not significantly different when ad libitum-fed controls and restriction-fed controls were compared even though body weights were significantly different. This suggests that bone strength comparisons can be made on bones that differ in size. Artificial weight loading of chicks or poults had no consistent effect on stress or modulus of elasticity. This would suggest that this type of exercise had no influence on bone strength. Turkey poults fed 28% dietary protein appeared to have stronger bones than those fed lower protein levels; however, when bone size and dimension are accounted for, no differences in bone strength resulted from the feeding of various protein levels. These findings suggest that stress and modulus of elasticity are better terms to use than force in making bone strength comparisons between groups of birds which may differ in body size and bone dimension.

Animals↗
PubMed1986

Nutritional value of aerobically fermented poultry manure and offal (Fermway) for broiler chicks.

The nutritional value of two samples of an aerobically fermented poultry product (Fermway) were evaluated for broiler chicks. Fermway is a combination of broiler house litter and offal from a broiler processing plant. A significant (P less than .05) growth stimulation was obtained with one sample at 8 to 16% of the diet. Feed efficiency generally improved, but the effect was not significant. Gizzard weight was also significantly increased.

Animal Feed↗
PubMed1986

Zinc supplementation: its effect on egg production, feed conversion, fertility, and hatchability.

Studies were conducted over four layer years using Single Comb White Leghorn hens, 24 to 68 weeks of age, to observe the effects of zinc supplementation of a corn-soybean meal layer ration on egg production, feed conversion, fertility, and hatchability. Pullets were housed in floor pens; 20 birds per pen. New Hampshire cockerels were used as sires. Treatments were the basal corn-soy-based diet (28 or 34 ppm zinc by analysis) with the following supplemental zinc levels (as the carbonate): 0, 10, 20, or 40 ppm. Feed, water, and crushed oyster shell were supplied ad libitum in all trials. No consistent production effects due to zinc supplementation were observed. Egg production, feed intake, and feed conversion were not improved by zinc supplementation. Fertility and hatchability, likewise, were not improved by zinc supplementation. The chicks produced showed no significant differences in 3-week body weights. However, the chicks produced from hens on the 28 ppm zinc (control) diet showed an increased incidence of zinc-related feather fraying. There was a significant (P less than .05) increase the first two laying trials and a numerical increase the last two trials. Thus it appears that 28 ppm of zinc, naturally supplied, is adequate for egg production, fertility, hatchability, and growth of progeny.

Animal Nutritional Physiological Phenomena↗
PubMed1985

Bursal, intestinal, and spleen weights and antibody response of chicks fed subtherapeutic levels of dietary antibiotics.

Experiments were conducted to study the influence of dietary antibiotics on the bursal, intestinal, and spleen weights and antibody responses of broiler chicks. Results indicate a tendency for chicks fed antibiotics to have heavier bursae but significantly reduced intestinal weights. The antibiotics had no effect on spleen weights and antibody response to sheep red blood cells. It was concluded that the beneficial effects of dietary antibiotics for chicks do not appear to be the result of an enhanced immunocompetence and that the use of antibiotics at subtherapeutic levels does not have an adverse effect on the chicks' humoral immune system.

Animals↗
PubMed1985

Hypokalemia secondary to primary hyperaldosteronism in a renal transplant recipient.

We describe a patient who developed persistant hypokalemia after renal transplantation that was initially attributed to diuretics and/or steroids. However after stopping the diuretic, the patient continued to have urinary losses of potassium (less than 30 mEq/day) at a time when the serum potassium was only 2.4 mEq/l and high urinary chloride (33 mEq/day) suggesting that the diuretics were not responsible for the hypokalemia and the metabolic alkalosis. The results of these simple laboratory tests and the presence of persistent severe hypokalemia prompted additional studies (peripheral renin activity; plasma aldosterone levels; and CT scan) that led to the diagnosis of left adrenal gland adenoma. Surgical removal of the adrenal adenoma led to the normalization of the serum potassium and a fall in the total CO2 content in plasma. To our knowledge this is the first report of a case of hypokalemia secondary to primary hyperaldosteronism in a renal transplant recipient.

Adenoma↗
PubMed1984

Leg deformities: inability to increase severity by increasing body weight of chicks and poults.

Five 4-week experiments were conducted to determine the effects of body weight on the severity of leg deformities in broiler chicks and turkey poults reared on raised wire floors. In order to make the influence of body weight independent of genetic, environmental, and nutritional effects, increasing body weight was achieved by harnessing steel weights on the backs of poults and chicks. In the first experiment, 3-day-old male and female chicks were harnessed with 0-, 1-, 2-, or 3-g weights (nine chicks per weight load). Weights were changed every 3 to 4 days until 4 weeks of age such that the artificial weight averaged 0, 3, 4.5, or 8.5% of their body weight. In Experiments 2 and 3, three replicates of 10 female chicks were assigned to isocaloric diets containing 18, 21, or 24% crude protein. Five chicks in each treatment and replicate were harnessed at 3 days of age with weights averaging approximately 13% of their body weight. Weights were changed weekly. Experiments 4 and 5 were designed similar to Experiments 2 and 3 except that male and female turkey poults were fed 22, 25, or 28% dietary crude protein and were harnessed with weights equal to about 8 to 10% of their body weight. Body weights of the birds were recorded weekly.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Campylobacter enterocolitis in New Orleans.

Campylobacter is being increasingly recognized as a common pathogen producing acute diarrheal illness. During 1981, all stool cultures at Charity Hospital were routinely screened for Campylobacter. Twenty-nine of 2,233 total cultures were positive. We performed a retrospective study to evaluate the disease's clinical picture and epidemiologic features. Campylobacter-positive cultures comprised 1.3% of all stool specimens and 21.6% of all positive cultures. Age, sex, and race in the Campylobacter group did not differ significantly from a comparison group. The distribution of the rates of Campylobacter-positive cultures did not show temporal trends. The clinical symptoms were nonspecific and the disease was usually self-limited, with diarrhea lasting from seven to ten days in untreated patients. The disease may occasionally be confused with a nonspecific inflammatory bowel disease. Thus, it is important that stool cultures be routinely screened for Campylobacter so that appropriate therapy can be administered.

Adolescent↗
PubMed1982

Effects of blood sampling by cardiac puncture on subsequent body weights of broilers.

The effects of blood sampling via cardiac puncture in broiler chicks 2 to 4 weeks of age on subsequent body weights were examined in three experiments. No differences were found in chicks bled or stabbed with 18, 22, or 25-gauge needles when compared to chicks not blood sampled. However, male chicks bled at both 2 and 3 weeks of age with a 25-gauge needle demonstrated elevated body weights at 8 weeks of age when compared to chicks not blood sampled.

Animals↗
PubMedDate not supplied

Immune and bone properties of chicks consuming corn contaminated with a Fusarium that induces dyschondroplasia.

A study was conducted to contrast the dyschondroplasia-inducing capability of several species of Fusarium with that of the natural fungi found in poultry diets and litter. Day-old broiler chicks were fed pure corn cultures of specific fungal isolates for 3 weeks. Humoral immunity to sheep red blood cells (SRBC), body weight, valgus and varus leg deformities, incidence of dyschondroplasia, and mechanical properties of the tibiotarsi were examined. F. equiseti #15 was the only fungal isolate to induce dyschondroplasia to any significant degree, which confirmed previous work in Minnesota. This isolate also suppressed growth rate and humoral immunity, although dyschondroplasia sometimes did occur without associated immunosuppression and growth depression. Bone strength of the tibiotarsal diaphysis was normal, and gross lesions of valgus and varus leg deformities did not appear to be related to the incidence of dyschondroplasia in the 3-week-old chicks.

Animal Feed↗