PARÂMETROS ELETROCARDIOGRÁFICOS DE CASCAVÉIS (Crotalus durissus, Linnaeus, 1758) EM CATIVEIRO.

Abstract

Endereço para correspondência: Daniel Rodrigues Stuginski: dstuginski@yahoo.com.br RESUMO: Apesar de a eletrocardiografia ser vastamente empregada na clínica veterinária, esta ferramenta ainda é pouco utilizada no diagnóstico de patologias em serpentes. Este trabalho teve como objetivo a caracterização dos parâmetros eletrocardiográficos da cascavel Crotalus durissus em cativeiro, sob condições controladas. Para isto, 23 serpentes foram submetidas ao exame eletrocardiográfico, aonde os seguintes parâmetros foram analisados: a frequência cardíaca, ritmo, eixo cardíaco, ondas P e T, complexo QRS, assim como os intervalos P-R e segmento S-T nas derivações cardíacas DI, DII, DIII, aVF aVL e aVR. Os resultados obtidos demonstraram que a técnica foi eficiente nas mensurações das deflexões cardíacas, porém a análise da frequência e ritmo geralmente foram prejudicados devido a um viés estresse-induzido e sua interpretação deve ser cautelosa. Os parâmetros eletrocardiográficos de Crotalus durissus determinados neste trabalho foram bastante consistentes e com mínimas variações, o que parece possibilitar sua utilização no diagnóstico das doenças cardíacas em serpentes. A escassez de padrões eletrocardiográficos em serpentes torna muito difícil a comparação e a interpretação de como as variáveis morfológicas, fisiológicas e ecológicas podem influenciar os parâmetros eletrocardiográficos, por este motivo, novas pesquisas que determinem os padrões eletrocardiográficos de diferentes espécies serão absolutamente necessárias para o uso do eletrocardiograma como ferramenta diagnóstica na rotina clínica.Palavras-chave: répteis; serpentes; eletrocardiograma. ELECTROCARDIGRAPHIC PARAMETERS OF RATTLESNAKES (CROTALUS DURISSUS, LINNAEUS, 1758 ) IN CAPTIVITYABSTRACT: Although electrocardiography is widely used in veterinary practice, this tool still has little application in diagnosing diseases of snakes. This study aimed to characterize the electrocardiographic parameters of Crotalus durissus in captivity, under controlled conditions. For this, 23 snakes were subjected to ECG examination, where the following parameters were analyzed: heart rate, rhythm, cardiac axis, P and T waves, QRS complex, as well as the P-R and S-T intervals in the heart leads DI, DII, DIII, aVF , aVL and aVR The results showed that the technique used was effective to the measurements of cardiac deflections, but the analysis of heart rate and rhythm is generally impaired by a bias-induced stress and its interpretation should be cautious. The electrocardiographic parameters of Crotalus durissus determined in this study were fairly consistent, with minor variations, which seem to allow its use for cardiac disease diagnosis in snakes. The scarcity of electrocardiographic patterns for snakes makes difficult a comparison and interpretation of how the morphological, physiological and ecological data can influence the electrocardiogram, therefore, further research to determine the electrocardiographic pattern of different species will be absolutely necessary to the use ...

Analysis of heart rate variability in corn snakes (Pantherophis guttatus)

“…Valentinuzzi et al, (1970) observed considerable variation in the T wave amplitude and duration over several days in snakes, although no immediate apparent cause of such variations was identified. The values for the ECG parameters in P. guttatus were lower than those for other species such as Boa constrictor (Conceição et al, 2014;Armelin et al 2019), Lampropeltis getuhts (Valentinuzzi et al, 1970) and Eunectes murinus (Strussmann, and Sazima,1991), but similar to those reported for Spilotes pullatus (Cruz and Junkes, 2008) and Crotalus durissus (Stuginski et al, 2011).…”

“…To record the ECG, the snakes were restrained individually with the ventral surface downwards in a clear plastic tube, with the cephalic one-third to half of the body inserted into the tube (Figure 1). Most work on heart rate in snakes is carried out under resting conditions and with anesthetized animals, a factor that can interfere with a full understanding of this animals (Lilywhite et al, 1999;Stunginsk;Fernandes;Grego, 2011). The ECG was recorded and analyzed using a computerized electrocardiograph with appropriate acquisition software (ECG PCV Acquisition Module 6.2, Tecnologia Eletrônica Brasileira -TEB, São Paulo, SP, Brazil).…”

“…The ease with which the ECG can be recorded makes this technique particularly useful for studying cardiac function in snakes and for monitoring the health status of these animals in a clinical setting, particularly in relation to the identification and characterization of cardiovascular and non-cardiovascular pathologies. Several studies have examined the ECG parameters of snakes such as Boa constrictor (boa constrictor) (Valentinuzzi et al, 1970), Spilotes pullatus (tropical chicken snake or yellow rat snake) (Kik and Mitchell, 2005;Cruz and Junkes, 2008) and Crotalus durissus (tropical rattlesnake) (Stuginski et al, 2011). (Linnaeus, 1766), commonly known as the red or eastern corn snake, is a non-venomous North American snake belonging to the family Colubridae.…”

What makes the heart of Boa constrictor (Squamata: Boidae) beat faster?

“…According to RASKE et al (2012), safe and inexpensive measurements of heart rate may be valuable for exotic animal medicine. STUGINSKI et al (2011) also found no relationship between HR and sex in Crotalus durissus Linnaeus, 1758. Sexual changes in the HR of snakes may occur due to pregnancy, which increases heart rate (BIRCHARD et al 1984).…”

“…However, it was difficult to perform in large snakes with strong muscles and a deep body cavity. The manual method is valuable when it is not possible to use more sophisticated methods such as electrocardiogram (e.g., VALENTINUZII et al 1969a, b, RUTSKINA et al 2009, STUGINSKI et al 2011, Doppler blood flow detector Figure 1. Relationship between body mass (g) and log 10 -transformed heart rate, measured as beats per minute in 30 individuals of Boa constrictor from Núcleo Regional de Ofiologia da Universidade Federal do Ceará.…”