Radiographic, ultrasound and endocrine evaluation of the reproductive cycle in red-foot tortoises (Geochelone carbonaria, SPIX, 1824) and yellow-foot tortoises (Geochelone denticulata, Lineu, 1766) / Avaliação radiográfica, ultrassonográfica e endócrina do ciclo reprodutivo de jabutis-piranga (Geochelone carbonaria, SPIX, 1824) e jabutis-tinga (Geochelone denticulata, Lineu, 1766)

AUTOR(ES)

Cynthia Maria Carpigiani Teixeira

DATA DE PUBLICAÇÃO

2009

RESUMO

The main objective of this study was to evaluate the reproductive cycle of red-foot (Geochelone carbonaria, SPIX, 1824) and yellow-foot tortoises (Geochelone denticulata, Lineu, 1766) using minimally invasive clinical and laboratory methods, such as radiographic and ultrasound images and hormone dosages. Seven G. carbonaria and 5 G. denticulata healthy females at reproductive age were kept together for 13 consecutive months. Mean variations in air humidity, pluviometric indexes, temperature and photoperiod were recorded weekly. All animals were evaluated once a month. Dorsoventral radiographic images of the animals in a standing position were obtained at the Fundação Parque Zoológico de São Paulo, by means of a fixed x-ray device, using 300 mA for 1/60 second. Eggs of each female that was analyzed by x-ray were measured using a caliper. Ultrasound examination was carried out using a convex micro transducer at two frequencies, 4 and 7.5 mHz. Ovarian structures (developing and developed follicles) were analyzed, as well as the presence or absence of shelled eggs inside the oviduct, using the cranial and inguinal acoustic windows for a little longer than 10 minutes. Ovarian structures were measured during the examination according to an internal scale of the device, and images were digitally recorded to be recovered later. Reproductive cycle was analyzed by means of serial blood collections for estrogen, progesterone, testosterone, and corticosterone dosage. Animals were physically restrained and blood samples were collected, which was preferentially performed by means of a puncture in the jugular vein. Samples were analyzed in the Laboratório de Dosagens Hormonais at the Departamento de Reprodução Animal, Faculdade de Medicina Veterinária at USP, using commercial solid phase radioimmunoassay kits (RIA) in order to assess differences in the annual cycle of the two species. A progesterone peak was observed two months before the peak of developing follicles in G. carbonaria, whereas G. denticulata showed follicular development two months after a marked increase in progesterone serum levels. However, progesterone peak was only observed in the beginning of the summer while in G. denticulata it was observed at the end. Testosterone and corticosterone serum levels observed in females of both species did not show significant variations throughout the year. Ultrasound examination showed vitellogenesis in females studied. An estradiol peak was observed in G. carbonaria in the beginning of the summer, and in G. denticulata in the end of this season, coinciding with a greater rate of developed follicles in ultrasound images. G. carbonaria females were more efficient in egg production than G. denticulata. Both species laid eggs once during the year.

ASSUNTO(S)

radiology reproduction reprodução radiologia ultrasound hormone dosage geochelone sp dosagem hormonal geochelone sp ultrassonografia

Documentos Relacionados

• Origens e ramificações das artérias aortas esquerda e dorsal do jabuti (Geochelone carbonaria, Spix, 1824)
• Topografia e morfologia do sistema urinário de jabuti (Geochelone carbonaria - Spix, 1824)
• Aspectos fisiopatológicos da retenção de ovos em Jabutipiranga (Geochelone carbonaria Spix, 1824)
• Morfologia e anatomia topográfica da medula espinal de jabuti das "patas vermelhas" (Geochelone carbonaria Spix, 1824)
• Efeitos do estresse e do cloridrato de quetamina sobre o padrÃo eletrocardiogrÃfico, freqÃÃncia cardÃaca e comportamento de jabutis-piranga (Geochelone carbonaria Spix,1824)