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Full-Text Articles in Animal Sciences
Effects Of 17Β Estradiol In The Metabolism And Morphology Of Bluegill Sunfish (Lepomis Macrochirus), Neeta Parajulee Karki
Effects Of 17Β Estradiol In The Metabolism And Morphology Of Bluegill Sunfish (Lepomis Macrochirus), Neeta Parajulee Karki
Masters Theses
Fish natural habitats are increasingly contaminated with various estrogenic compounds, including 17β estradiol (E2). This compound causes adverse effects on the reproductive system of male fish; however, the effects of E2 on other aspects of fish metabolism, morphology and histopathological changes in internal organs are not well known. The objective of this study is to evaluate the effects of E2 exposure on the basal and stressed metabolic rate, morphological changes in body shapes, and histological changes in the liver tissues of sunfish species. Fish were held individually in ten gallon tanks under two treatments of 40 and 80 ng/L and …
Effects Of Methylxanthines On Newborn Rat Respiration, Craig Gatto
Effects Of Methylxanthines On Newborn Rat Respiration, Craig Gatto
Masters Theses
Methylxanthines (MX), such as theophylline, are commonly used in the treatment of recurrent apnea due to their stimulant effects on the respiratory center. Structure-activity studies have demonstrated that substitution of alkyl groups on the 3-position of the xanthine nucleus results in increased bronchodilator potency, while substitution on the 1-position is important for adenosine antagonism and CNS stimulation. Three different alkylxanthines were studied to determine the structural requirements for respiratory stimulation. Respiratory rates and volumes were determined in 4- to 7-day-old rats using a volume displacement body plethysmograph. Measurements were made before and at 5 minute intervals after subcutaneous (s.c.) injection …
The Effects Of Xanthine And Adenosine Analogs On Rat Pup Diaphragmatic Contractility, Liam C. Farrell
The Effects Of Xanthine And Adenosine Analogs On Rat Pup Diaphragmatic Contractility, Liam C. Farrell
Masters Theses
Methylxanthines are commonly used in the treatment of respiratory disorders such as asthma, apnea of prematurity and Cheyne-Stokes respiration. Recently, certain methylxanthines have been found to potentiate the contraction of the diaphragm and increase contraction strength of the fatigued diaphragm. The mechanism of action of the methylxanthines is unknown. Three theories have been proposed but each has its supportive and negative points. One theory is that methylxanthines inhibit cyclic AMP phosphodiesterase (PDE) which facilitates contraction by increasing cyclic AMP levels in the cell. Another theory is that methylxanthines antagonize adenosine, thus blocking the adenosine-induced inhibition of contraction. The third theory …
Treflan And The Oxygen Consumption Of Green Sunfish (Lepomis Cyanellus), Barbara Jo Warner
Treflan And The Oxygen Consumption Of Green Sunfish (Lepomis Cyanellus), Barbara Jo Warner
Masters Theses
Oxygen consumption rates of 51 green sunfish (Lepomis cyanellus, Rafinesque) were monitored over five hours exposure to Treflan E.C. concentrations of 0, 0.32, 0.56, 1.0, and 2.0 ppm. There was a great variation in the responses of the fish at each concentration; and Student's t-tests revealed no significant differences. However, graphs of the mean hourly oxygen consumption rates showed certain trends. During the fifth hour of exposure, there appears to be an acclimation to the Treflan at concentrations of 0.32 and 0.56 ppm; but no such acclimation at the higher concentrations of 1.0 and 2.0 ppm. Hourly oxygen …
The Effects Of Acute Stress On Adrenal Ascorbic Acid Levels, Robert Joseph Collier
The Effects Of Acute Stress On Adrenal Ascorbic Acid Levels, Robert Joseph Collier
Masters Theses
The diurnal rhythm of adrenal ascorbic acid (DAR) displays an inverse relationship to the diurnal rhythm of circulating levels of plasma corticosteroids. Alloxan monohydrate, 175 mg/kg body weight was given subcutaneously to albino rats to determine the effect of the diabetic state on the DAR. A total of 200 female albino rats were divided into two study groups. Study Group I was composed of 150 animals divided into populations of 15, each including 3 controls. Study Group II was composed of populations of 5, each group containing all controls or all alloxinated rats. The populations of 15 were sacrificed at …
The Effects Of Crowding On The Diurnal Ascorbic Acid Levels Of Albino Rats, Mary Jo Barr
The Effects Of Crowding On The Diurnal Ascorbic Acid Levels Of Albino Rats, Mary Jo Barr
Masters Theses
The adrenal physiology of the albino rat was studied through the measurement of adrenal ascorbic acid levels. A cyclic phenomenon was observed which follows the diel periodicity of the animal. Ascorbic acid values were found to be characteristically higher in males than in females. A similar difference was also seen in populations divided into young animals (body weight less than 175 grams) and old animals (body weight greater than 175 grams). Crowding, induced by manipulating the area of cage space per gram of body weight, was observed to be a definite stressor and caused the adrenal ascorbic acid levels to …