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Reproductive Biology Of The Rat Lungworm Angiostrongylus Cantonensis (Metastrongyloidea: Angiostrongylidae), Grace Spatafora Harris

Master's Theses

Twenty rats (Rattus norvegicus) received infective inocula of 5, 10, 20, and 40 third-stage larvae of Angiostrongylus cantonensis. The effects of varying doses of larvae on prepatent period larval production, worm establishment, worm size, and fertility were studied. The aquatic gastropod Biomphalaria glabratta was the experimental intermediate host.

The duration of the prepatent period varied from 37 to 45 days. The shortest prepatent period was observed in animals that received the highest infective inoculum. The prepatent period showed a significant inverse relationship with increasing inoculum size. Larval production increased logarithmically, followed by a plateau phase. The number of larvae per …

An Electrophoretic Comparison Of Gene Loci In Etheostoma Nigrum And Etheostoma Olmstedi From The James River Drainage, Virginia, Randall Keith Falls

Master's Theses

As many as five different populations of Etheostoma nigrum and Etheostoma olmstedi have been identified in the James River drainage, Virginia. Genetic variation of these populations was analyzed with starch gel electrophoresis and revealed only three distinct populations. Nine loci encoding five enzyme systems and two loci encoding muscle proteins were examined in tissue homogenates. All populations were monomorphic with the exception of the esterase-3 (Est-3), phosphoglucomutase (Pgm-1) and phosphoglucose isomerase (Pgi) loci. Two alleles of Est-3 exhibited activity in the homozygous and heterozygous conditions. Pgm-1 occurred as two alleles with a high degree of heterozygosity (46% for E. nigrum …

The Effects Of Osmotic Stress On Sodium, Potassium, And Chloride Metabolism In The Mongolian Gerbil, Meriones Unguiculatus, Mark William Hagood

Master's Theses

The effects of osmotic stress on sodium, potassium, and chloride metabolism and the physiological mechanisms governing these ions were studied in the Mongolian gerbil, Meriones unguiculatus. Animals were subjected to dietary regimens ranging from sodium-free to high-sodium diets for sixty days. Results indicate the gerbils were not physiologically stressed by the imposed diets. Apparently the animals regulate ion metabolism via intrarenal mechanisms and pituitary antidiuretic hormone while behavior and adrenal cortical activity are insignificant.