Mediterranean tortoises, Hermann’s tortoise (Testudo hermanni) and spur-thighed tortoise (Testudo graeca) have similar conservation issues in Spain, although the first has disappeared from most of its original habitat and is more threatened. Both in-situ and ex-situ conservation programs should include adequate health management. One of the main aspects is the establishment of reference values for blood parameters for the proper interpretation and evaluation of the health status of each species. In the first study, conducted in the western Mediterranean tortoise (T. h. hermanni), the effect of two types of anticoagulants, heparin lithium and EDTA tripotassium, on hematological parameters was evaluated. Heparin lithium is considered as the anticoagulant of choice for blood samples of these chelonians. Infectious diseases can compromise the viability of tortoise populations and are important factors to consider in the management of captive populations and for the release of animals, to reinforce wild populations. In the second study, an outbreak of chronic rhinitis associated with a herpesvirus in a captive population of spur-thighed tortoise is described. The most relevant clinical findings were bilateral effusion rhinitis, accompanied by stomatitis and glossitis. An hematological and serum biochemical study was performed and compared with data from healthy animals from three different populations. Diseased animals showed heteropenia, lymphocytosis, increased AST activity and higher α-globulin concentration. Some tortoises showed normocytic and normochromic anemia. The lesions were confined to the respiratory tract and the oral cavity, with marked epithelial hyperplasia and presence of mixed inflammatory infiltrate in the epithelium of the oral, nasal and tracheal mucosa. Electron microscopy revealed the presence of intracytoplasmic and intranuclear viral particles whose size, shape and distribution pattern corresponded to a herpesvirus. Captive breeding of endangered species are more subjected to health risks that wild populations. In the third study, an episode of systemic atypical mycobacteriosis in a captive population of Western Hermann’s tortoise is described. The symptoms appeared at the end of the period of hibernation, in the form of anorexia, dullness and lethargy, with inflammatory and edematous lesions on the limbs and tail. Blood samples, joint taps and skin biopsies were performed. Lately, euthanasia of affected animals was performed. Most tortoises showed marked leukocytosis, with heteropenia, monocytosis and a large number of mononuclear cells, and five animals had anemia. An increase in the values of AST, ALT, LDH and FA, a decrease in bile acids and hyperproteinemia with increased globulin and decreased albumin and A/G ratio were observed. In joint taps, mononuclear cells with phagocytosed bacillary structures were obseved. Ziehl-Neelsen stain revealed the presence of acid-fast bacteria. Lesions were observed in ovaries, pancreas, lungs, spleen, heart, muscle, kidney and liver. Culture and identification were positive for mycobacteria and molecular sequencing lead to the identification of Mycobacterium nonchromogenicum. Health aspects in reptiles are insufficiently studied and assessed for captive breeding and conservation of threatened species. In this study, it was found that lithium heparin is the anticoagulant of choice for blood sampling in Mediterranean tortoises and infections such as those cause by herpesvirus and mycobacteria may compromise the ex-situ conservation of these species.
Estudio sanitario de las tortugas terrestres mediterráneas (Género Testudo) e implicaciones para su conservación
Jesús Muro (Author). 11 Dec 2015
Student thesis: Doctoral thesis
Student thesis: Doctoral thesis