May Salivary Chromogranin A Act as a Physiological Index of Stress in Transported Donkeys? A Pilot Study

Welfare of equidae during transport

In the framework of its Farm to Fork Strategy, the Commission is undertaking a comprehensive evaluation of animal welfare legislation. This opinion deals with the protection of horses and donkeys during transport. While the opinion focuses primarily on road transport of horses, there are specific sections dealing with the transport of horses on roll-on-roll-off ferries, horses transported by air and the transport of donkeys. In addition, the opinion covers welfare concerns in relation to a specific scenario identified by the European Commission related to the transport of horses on long journeys to slaughterhouses. Current practices related to transport of horses during the different stages (preparation, loading and unloading, transit and the journey breaks) are described. Overall, 13 welfare consequences were identified as being highly relevant for the welfare of horses during transport based on severity, duration and frequency of occurrence: gastro-enteric disorders, handling stress, heat stress, injuries, isolation stress, motion stress, prolonged hunger, prolonged thirst, respiratory disorders, resting problems, restriction of movement, sensory overstimulation and separation stress. These welfare consequences and their animal-based measures are described. A variety of hazards were identified related to factors such as inexperienced/untrained handlers, lack of horse training, structural deficiencies of vehicles/facilities, poor driving skills/conditions, horse separation/regrouping, unfavourable microclimatic and environmental conditions and poor husbandry practices. The opinion contains general and specific conclusions in relation to the different stages of transport. Recommendations to prevent hazards and correct or mitigate welfare consequences have been developed. Recommendations were also developed to define quantitative thresholds for microclimatic conditions within the means of transport and for space allowance. The development of welfare consequences over time was assessed in relation to maximum journey time.

Measurement of catestatin and vasostatin in wild boar Sus scrofa captured in a corral trap

Objective

Our aim was to analyse the chromogranin A-derived peptides vasostatin and catestatin in serum from wild boar (Sus scrofa) captured in a corral trap. Acute capture-related stress quickly leads to a release of adrenalin and noradrenalin, but these hormones have a short half-life in blood and are difficult to measure. Chromogranin A (CgA), a glycoprotein which is co-released with noradrenalin and adrenalin, is relatively stable in circulation and the CgA-derived peptides catestatin and vasostatin have been measured in domestic species, but not yet in wildlife.

Results

Vasostatin and catestatin could be measured and the median (range) serum concentrations were 0.91 (0.54–2.86) and 0.65 (0.35–2.62) nmol/L, respectively. We conclude that the CgA-derived peptides vasostatin and catestatin can be measured in wild boar serum and may thus be useful as biomarkers of psychophysical stress.

Habituation to Transport Helps Reducing Stress-Related Behavior in Donkeys During Loading

Adopting proper animal management strategies, including training, might reduce to a substantial extent the adverse effects of transport-related stress in animals. The aim of this study was to evaluate the effect of habituation to transport on stress-related behaviors and physiological indicators during loading and unloading in donkeys. Fourteen donkeys were recruited and divided in two treatment groups: Habituation (H; M = 5, F = 2) and Control (C; M = 5, F = 2). H donkeys were gradually habituated to be transported, traveling together with their mothers and other adult donkeys well-accustomed to transport, while C donkeys had never been transported before. Loading and unloading phases were video recorded and behavior was analyzed. Saliva samples for cortisol concentration determination were collected at rest and after unloading. Latency time to load was significantly shorter for H donkeys than C donkeys (Mann-Whitney; p = 0.004). C donkeys also showed significantly more stress-related behaviors (Mann-Whitney; p = 0.026) and required a higher but not statistically significant number of human interventions to load. Cortisol concentration increased in both groups, but no differences were found between them (Mann-Whitney; p > 0.05). These results suggest that habituation to transport could mitigate stress during loading procedures in donkeys reducing loading time, frequency of stress-related behaviors and diminishing the need of human intervention.