Symmetrical Dimethylarginine as a Diagnostic Parameter in Hermann's Tortoises (Testudo hermanni)

[Assessment of the nutritional condition in Mediterranean tortoises (Testudo spp.) - an overview]

Assessing the nutritional status is a crucial component of the general examination for all patients. However, in tortoises, this may be challenging due to their unique anatomy and limitations of the shell. Despite their popularity, there is currently no established standard for assessing their nutritional status and body condition. Depending on the equipment of the veterinary practice, different examination methods are available. As each method has advantages and disadvantages and no clear references exist, an assessment of the nutritional status of tortoises should always consist of several factors. Therefore, detailed knowledge of tortoise physiology is essential when selecting the appropriate method. This article presents an overview of the currently best-known methods and their possible applications in veterinary practice, considering the physiological characteristics of tortoises.

Reference Interval Creation for Symmetric Dimethylarginine (SDMA) in Healthy Hispaniolan Amazon Parrots (Amazona ventralis) and Quaker Parrots (Myiopsitta monachus)

Renal disease is often identified as a cause of morbidity and mortality in avian patients. However, currently, early antemortem detection of renal disease in avian patients is difficult. Anatomical and physiological differences between mammals and birds mean the use of commonly employed diagnostic testing (ie, measurement of blood urea nitrogen [BUN] and serum creatinine, urinalysis, and ultrasonography) are either nondiagnostic or difficult to achieve. Symmetric dimethylarginine (SDMA) is considered a more sensitive marker for renal disease in humans, dogs, and cats. However, SDMA has not yet been assessed for diagnostic use in any psittacine species. In this study, we establish reference ranges for SDMA in both Hispaniolan Amazon parrots (Amazona ventralis, HAP) and Quaker parrots (Myiopsitta monachus, QP). Blood was collected from 23 Amazon parrots and 32 Quaker parrots maintained in research facilities. Measurement of SDMA through a commercially available immunoassay (IA-SDMA) as well as creatinine, BUN, uric acid, phosphorus, calcium, sodium, potassium, and chloride were determined through IDEXX Laboratories. Plasma SDMA concentrations ranged from 6 to 15 µg/dL and 3 to 15 µg/dL for the HAP and QP, respectively. Sex was a confounding factor for the QP population, but sex did not have a significant effect on SDMA for the HAP population. No significant correlations were identified between SDMA concentrations and other parameters in either psittacine species. Our results show proof of concept for the IA-SDMA and provide reference intervals for SDMA in HAP and QP. Further investigation is required to determine the validity of this assay and the predictive power of SDMA in the detection of renal impairment for parrots and other common companion birds.

Body condition scoring facilitates healthcare monitoring in Hermann's Tortoises (Testudo hermanni ssp.)

Clinical assessment of body condition is crucial in captive and free-ranging reptiles, since a large percentage of diseases result from inadequate nutrition. However, preventive health care is restricted by the lack of a practical method for the assessment in tortoises. Pre-existing evaluation systems based on weight and shell measurements are laborious and ignore the clinical presentation of the animal. The present study aimed to facilitate the assessment by establishing a body condition score. A total of 373 Hermann's Tortoises (Testudo hermanni) (n = 281 tortoises kept as pets in Germany and n = 92 tortoises originating from a free-ranging population (68) or a rearing station (24) in France) were examined and data (weight (g), carapace length (cm), width (cm), height (cm)) were recorded in a standard protocol between October 2020 and October 2021. A modified version of a body condition score for Mojave Desert Tortoises (Gopherus agassizii) (1 = cachectic, 3 = ideal, 5 = obese) was utilized and tested against pre-existing shell measurement systems (Jackson's ratio, body condition index, volume condition index, circumferential product). German captive tortoises were significantly heavier and larger than French specimens. In the Spearman's correlation matrix, the body condition score showed a statistically significant correlation with all measurement methods in the total population of captive tortoises (Testudo hermanni boettgeri), with a medium correlation strength, and a lack of correlation in free-ranging tortoises (Testudo hermanni hermanni). However, individual animal data suggested misleading results of mathematical equations in terms of body condition. Clinical evaluation of tortoises, including a body condition score, should be considered essential to provide good healthcare and should be an integral part of general examination.

[Diagnosis of kidney diseases in European tortoises (Testudo spp.)]

The diagnosis of kidney diseases in tortoises is only possible to a very limited extent on the basis of the general examination due to the development of unspecific disease symptoms. Extensive additional examinations are required to confirm the diagnosis. In addition to blood and urine tests, imaging techniques such as X-ray, computed tomography and MRI are suitable for visualizing the skeletal and organ systems, while additional samples can be taken during an endoscopic examination. There are clear species-specific differences with regard to the reference values of the laboratory parameters, which are in part significantly influenced by environmental influences, the seasons or even gender. It can also be seen that kidney diseases in tortoises kept in captivity are usually very advanced at the time of diagnosis, since these animals, like reptiles in general, show a pronounced lack of symptoms. Annual checks by a veterinarian specialized in reptiles can help to detect diseases at an early stage.