Biochemical and hematological reference intervals for Krefft’s turtles Emydura macquarii krefftii from the Burnett River Catchment, Australia

Abstract

Biochemical and hematological reference intervals have not previously been reported for Emydura macquarii krefftii. In 2009, 56 E. m. krefftii were captured by hand from the Burnett Catchment, clinically assessed to determine health status and blood sampled. Reference intervals were calculated from the 35 clinically healthy turtles using techniques established in other chelonid species. Aberrant blood results were identified from the 21 clinically unhealthy turtles. Low numbers of observed cases of creatine kinase, glucose, magnesium, phosphorus and uric acid outside of the blood biochemistry reference interval were recorded, as were high numbers of observed cases of estimated eosinophils, thrombocytes and total leukocyte counts outside of the hematological reference interval. Lesions of the shell and plastron (shell rot) were observed in 38% (21/56) of the examined healthy and unhealthy turtles. Microbiological assessment of a subsample (n = 7) of these lesions grew Aeromonas veronii 100% (7/7), Aeromonas hydrophila 29% (2/7) and Acinetobacter baumannii 14% (1/7). Of the examined turtles, 13% (7/56) had evidence of opacity of the lens or anterior chamber of the eye and 70% (39/56) had erythema of the neck, axillary and inguinal soft tissues. Not all observed cases of erythema were associated with clinical ill-health. The anomalous blood results and clinical findings identified in this study suggest disease processes which may have resulted from causative agents in the surrounding environment.KEY WORDS: Aeromonas · Blood biochemistry · Disease · Environmental factor · Hematology · Emydura macquarii krefftii · Shell rot Resale or republication not permitted without written consent of the publisherDis Aquat Org 95: [43][44][45][46][47][48] 2011 Emydura macquarii krefftii (Grey 1871) is an Australian native turtle found in Queensland east of the Great Dividing Range from the Cape York Peninsula southward to Cape Charlotte Bay. The species exhibits sexual dimorphism, with females being larger than males. Mating takes place in autumn, late winter and spring, and nesting from September to January. The eggs are white, hard-shelled, and ellipsoidal and normal clutch size may vary from 4 to 18 eggs. Longevity has not been determined (Cann 1978, Legler & Cann 1980, Georges 1983.This study has been initiated in response to a perceived increase in the numbers of free-ranging freshwater turtles in poor body condition in the Burnett River and associated deaths of some of these turtles. Intermittent studies of Emydura macquarii krefftii river turtle populations in the Burnett Catchment in Queensland have been undertaken since 1994 (Tucker et al. 2000, Hamann et al. 2007, Hamann et al. 2008 (DERM unpubl. data).Causes for these recent events are believed to be of environmental origin but, in the absence of baseline data such as blood biochemical and hematological reference intervals and reported 'background' pathogens, determining the causative agent is speculative.The aims of this study were to develop reference i...

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