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Geology topics

J.E. Lovich

Publications and source records attributed to J.E. Lovich.

At least 37 records · Page 2Linked to original sources
USGS1996

Prevalence and histopathology of shell disease in turtles from Lake Blackshear, Georgia

Turtles in Lake Blackshear, Crisp County, Georgia (USA) were evaluated for shell disease during intensive trapping efforts on 8 and 9 May 1990. The disease was most prevalent in Pseudemys concinna (74%) and Trachemys scripta (35%). The degree of necrosis on the carapace was significantly positively correlated with the degree of necrosis on the plastron in T. scripta ( r s = 0.50), but not in P. concinna ( r s = 0.06). Female T. scripta with lesions were significantly larger than females without lesions. Lesions were not detected on six other species of turtles. Some areas contained multinucleate osteoclasts that were destroying bone. No tumors were detected in soft tissue samples.

Journal of Wildlife Diseases↗
USGS1991

Male sex steroids and hormonal control of male courtship behavior in the yellow-bellied slider turtle, Trachemys scripta

Survey of androgens and estrogens in serum, liver and testes of male yellow-bellied slider turtles, Trachemys (= Pseudemys ) scripta , a species exhibiting dissociated gametogenesis age-dependent melanism, revealed the presence of numerous androgen precursors, androgens, androgen metabolites, and estrogens in quantities varying with season, tissue, and male coloration. The most commonly found and abundant androgens in all males were dehydroepiandrosterone (DHEA) and androstenedione, which were present at significantly higher levels in testes than in serum or liver. Epitestosterone was found in the serum and liver of only melanistic males; testosterone was only rarely recovered. Behavioral testing of castrated male turtles implanted with various androgens, as well as intact and sham-operated controls, revealed that melanistic males courted more frequently than nonmelanistic males, and that exogenous testosterone was most effective in inducing courtship behavior in castrated males.

Comparative Biochemistry and Physiology, Part A: M↗