Hormonal and behavioural stress responses to capture and radio-collar fitting in free-ranging pampas deer (Ozotoceros bezoarticus)

Abstract

This study evaluated the short-term hormonal and behavioural responses to capture and radio-collar fitting in free-ranging pampas deer (Ozotoceros bezoarticus). Twenty adult deer (eleven females and nine males) were captured in the South Pantanal wetland (Brazil) and equipped with VHF radio-collars (marked deer). Untreated adult deer of the same sex were randomly chosen as the control group (nine females and nine males). On the day following capture, an observer followed all deer for faecal collection and behaviour evaluation. Faecal samples were immediately refrigerated and frozen at-20°C within a maximum of 12 h. Faecal glucocorticoid metabolites (FGM) were measured using an 11-oxoaetiocholanolone enzyme immunoassay. A qualitative behaviour assessment and the consequences of capture were evaluated using pre-defined terminologies and scores. Flight distance was recorded using a range finder. FGM increased from 19-22 h after capture onwards and peak concentrations were five times (median) higher as the respective baseline values. FGM values of marked deer were significantly higher at 22-25 and 25-28 h compared with controls. Marked male but not female deer had significantly higher FGM values at 22-25 and 25-28 h compared with their baseline values. Marked deer were significantly more fearful, less sociable and defensive than controls. The absences of significant increases of FGM in the captured female deer may indicate that females are less prone to capture stress. The significantly more fearful, and less sociable and defensive patterns observed in marked deer may be relevant during capture of lactating females or in areas with high predator pressure.

Being stressed outside the park—conservation of African elephants (Loxodonta africana) in Namibia

“…The fGCM concentrations were log-transformed to obtain normal distribution, as is standard procedure with hormone data ( Creel et al , 2002 ; Munshi-South et al , 2008 ; Tingvold et al , 2013 ; Munerato et al , 2015 ). Linear multivariate mixed regression models ( lmer function, ‘lme4’ package) were developed using the package MASS ( Venables and Ripley, 2002 ).…”

Physiological Stress Reactions in Red Deer Induced by Hunting Activities

“…These results were in agreement with those obtained by Huber et al [ 17 ] who did not find differences in the concentration of FCMs between female and male red deer. However, other studies described sex-specific differences in glucocorticoid levels for some ruminant species [ 47 , 48 ] as well as age variations [ 49 ]. Regarding the influence of the reproductive state on stress levels, changes in cortisol levels were reported in red deer, with older females having higher cortisol levels in late gestation than non-pregnant females [ 50 ].…”

Stress steroid levels and the short-term impact of routine dehorning in female southern white rhinoceroses (Ceratotherium simum simum)

“…Significant short-term increases in fGCM levels following capture and radiocollar fitting have been described for free-ranging deer (Munerato et al 2015), and routine claw trimming of physically restrained domestic cows has resulted in significant increases in fGCM levels (Pesenhofer et al 2006). Chemical immobilisation and trimming of the horn are two inseparable components inherent to the dehorning process of rhinos.…”