Date of Award

1994

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

First Advisor

Dudley D. Culley, Jr

Abstract

This study was conducted to: (1) determine the effects of stocking density and dietary protein:energy ratio on survival, growth, feed consumption, feed conversion, lipo-somatic index, dress-out percentage, and productive protein value of common snapping turtles; and (2) determine the fatty acid composition of muscle, liver, and fat bodies of wild common snapping turtles and common snapping turtles fed a diet of known fatty acid composition. Hatchling common snapping turtles, Chelydra serpentina, were stocked at five or 10 animals per container (29 and 58 turtles/m$\sp2$, respectively), and fed one of seven prepared diets. Six diets contained 30, 35, or 40% protein at two digestible energy levels (7 or 9 kcal DE/g protein). The seventh was a reference diet (66% protein and 5 kcal DE/g protein) formulated to equal or exceed the whole-body essential amino acid composition of wild, common snapping turtles. Hatchling turtles were fed a formulated feed of known fatty acid composition, analyzed for tissue fatty acids, and compared to the fatty acid composition from muscle, liver, and depot fat from wild, adult turtles. Hatchling turtles stocked at 58 turtles/m$\sp2$ exhibited greater mortality (P = 0.026), less weight gain (P = 0.079), and lower lipo-somatic index (P = 0.004) than turtles stocked at 29 turtles/m$\sp2$. Turtles fed the reference diet achieved greater weight gain, higher whole-body protein, and higher percentage whole-body protein than those fed the other diets (P $<$ 0.001). The increased growth of turtles fed the reference diet indicated that the protein (amino acid) content and/or energy:protein ratio of the reference diet was responsible for the increased growth compared to other diets. The fatty acid composition of lipid from tissues of the hatchling turtles fed the alligator feed reflected dietary fatty acid composition. The fatty acid composition of whole-lipid, polar lipid, and nonpolar lipid of muscle, and fat bodies of common snapping turtles fed alligator feed exhibited the greatest variability; liver polar lipids exhibited the least variability when compared to wild turtles. Studies to determine optimum tissue fatty acid composition of adult and juvenile common snapping turtles and minimum dietary fatty acid and protein:energy requirements for optimum growth and reproductive success should be undertaken.

Pages

65

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