Controle autonômico da freqüência cardíaca em Spilotes pullatus (Colubridae) como determinante das respostas de medo

Abstract

RESUMONeste estudo, investigaram-se as modificações fisiológicas em Spilotes pullatus, como determinantes das respostas ao medo, obtidas pela exposição ao eletrocardiograma. Foram utilizadas quatro serpentes com média de peso de 0,5±0,06kg. Dois minutos após a fixação dos eletrodos, as serpentes apresentavam-se imóveis, com redução significativa na freqüência cardíaca e aumento nos intervalos PQ, QRS, RR e RT (P<0,05). Os resultados sugerem que a presença de sintomas de medo pode gerar riscos à saúde desses animais.Palavras-chave: serpente, caninana, bradicardia, eletrocardiograma, medo ABSTRACTThis study investigated electrocardiographic changes in Spilotes pullatus using four snakes weighing 0.5±0.06kg. Two minutes after that electrocardiogram apparatus had been fixed in Spilotes pullatus, snakes were immobile and there was a significant reduction of the heart rate and an increase in PQ, QRS, RR, and RT intervals (P<0.05). Results suggest that the presence of fear symptoms may represent a risk to the health of snakes.

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).…”

“…Clinically, HRV analysis can be used to detect changes in cardiac function and neuronal activity that may be indicative of the animal´s general health, with a high HRV indicating a well-regulated system and a low or reduced HRV indicating potential health problems; such analyses can improve the interpretation and management of heart disease in reptiles (Veras and González, 1999;Veras et al, 2000;Wang et al 2003;Cruz and Junkes, 2008;La Rovere et al, 2012;Gemer, 2016;Shaffer and Ginsberg, 2017).…”

“…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.…”

“…Spilotes pullatus (Cruz and Junkes, 2008). SD1 is associated with the short-term modulation of heart rate variability that is influenced by the parasympathetic nervous system, whereas SD2 is associated with the long-term modulation of heart rate variability that is influenced by the sympathetic nervous system (Roy and Ghatak, 2013).…”

“…A variety of environmental stimuli can be stressful to snakes. Cruz and Junkes (2008) noted that exposure of the snake Spilotes pullatus to stress resulted in stimulation of the vagus nerve and an increase in the RR interval, leading to bradycardia.…”