Physiological and behavioral effects of handling and restraint in the ball python (Python regius) and the blue-tongued skink (Tiliqua scincoides)

Abstract

Reptiles are handled during transport, veterinary care, education programs, and as companion animals. This study investigated corticosterone levels (CS), heterophil/lymphocyte ratio (H/L), and behavioral responses to routine handling in the ball python (Python regius) (n=4) and the blue-tongued skink (Tiliqua scincoides) (n=3). We validated the RSL I 1~ Corticosterone Kit for rodents for parallelism and recovery, and found this to be a precise and highly specific means of CS measurement in reptiles. To determine the optimal blood sampling time, animals were sampled throughout a 24-hour cycle under two different light regimens, one a 12L:12D and one in which a red light was on during the dark period. The diurnal pattern of cs did not differ as a result of light regimen. Python peak cs levels occurred at 2400 hours during the peak locomotor activity period and at 1200 hours when body temperature was highest, while skinks showed no significant cs rhythm.Heterophil/lymphocyte ratio values indicated that cardiac puncture did not cause chronic stress although it may be an acute stressor. Animals were then handled gently, manually, or were container restrained (CR) for 10 minutes. Although skink cs was unaffected by treatment, CR caused an elevated level of cs in pythons which may indicate short-term stress. There were no differences in H/L ratio or changes in activity level in either species. Brief periods of routine handling of the study species in captivity thus did not cause chronic stress as measured by CS, H/L ratio, and activity parameters.

Prevalence of Salmonella in Australian Reptiles

“…Handling of reptiles is an important trigger for increases in both corticosterone and adrenal catecholamines (Lance and Lauren, 1984;Grassman et al, 1992;Kreger and Mench, 1993). In free-ranging animals, restraint is usually associated with consumption by a predator thus handling may elicit a fight or flight response (DeNardo, 2006).…”

How much stress do researchers inflict on their study animals? A case study using a scincid lizard, Eulamprus heatwolei

“…Thus, our working definition of stress is 'the physiological response of an animal to an experimental stimulus, as measured by elevated circulating glucocorticoid levels'. Changes in plasma corticosterone levels have been used to assess the impact of capture, handling, restraint and confinement on reptilian species (Moore et al, 1991;Cree et al, 2003;Cree et al, 2000;Mathies et al, 2001;Kreger and Mench, 1993;Cash et al, 1997), but the amount of stress induced by alternative commonly used research procedures beyond initial capture and housing has not been previously assessed. The present paper describes a study that set out to quantify the ways in which plasma corticosterone levels in lizards are affected by a variety of methods that are commonly used in fields of research such as behavioural ecology and microevolution.…”

Dropping the Ball? The Welfare of Ball Pythons Traded in the EU and North America

“…However, numerous scientific and other reports emphasise that snakes, including more sedentary species such as the Ball python, require the ability to fully straighten their bodies to satisfy their need for behavioural normality, exercise, avoidance of stress and disease, alleviation of physical discomfort, and achievement of physical comfort [26,29,[37][38][39] For example, Kreger and Mench [40] found that Ball pythons that were restrained in a container prior to handling demonstrated a significant rise in plasma corticosterone (CS) levels, potentially indicating an acute stress response. Given that the majority of the snakes observed during our study were not given the ability to extend their bodies to full and unrestricted natural length, it is arguable that the current husbandry practices could likely be having a negative impact on the welfare of the Ball pythons that are housed in this manner.…”