EuroTier 2018

•••2••• Innovationen How to prevent stressful situations in pens Optimism remains in chickens in enriched environments despite exposure to stress C hickens that grow up in an en- vironment that they perceive as more diverse and manageable, retain an optimistic view of life and cope with stress better than individuals that grow up in more sterile surroundings, according to a new study. A team of research- ers lead by researchers from Linköping University, Sweden, measured how optimism in chick- ens is affected by stress. But how can you measure opti- mism in chickens? Young chicks were taught to distinguish be- tween black and white, where one of the colours contained a reward, through a process known as associative learning. The chick- ens were then given a new chal- lenge, and presented with grey symbols intermediate between the rewarded and the unreward- ed colours. The researchers meas- ured the response of the birds toward the grey colour where chickens that reacted to grey in the same manner as they had reacted to the rewarded colour were considered to be optimistic. The researchers also measured levels of dopamine, a signal sub- stance, in the brain of these chickens. In humans, dopamine is linked to well-being and opti- mism. The results showed that chickens assessed to be optimis- tic had higher levels of dopamine. “In this study we wanted to in- vestigate how stress influences optimism, and whether a more complex environment during de- velopment can buffer and coun- teract negative effects of stress,” says Hanne Løvlie, professor at Linköping University, who has led the study. The researchers compared chickens that grew up in rather sterile surroundings to those that had grown up in a more complex and stimulating environment. “One interesting result was that chickens in both types of environments were equally optimistic before being exposed to stress,” says Løvlie. In order to expose the chickens to stress, the researchers created an unpredictable environment for them by moving things around in the animals’ pens, and expose them to irregular light and noise intervals. When the chickens were exposed to stress the differences appeared: individuals that had lived in a simpler environment lost their optimistic attitude af- ter being exposed to stress, while chickens in a more complex envi- ronment retained their optimistic attitude and thus seemed to be better able to cope with stress. “If a chicken can hide under some- thing or fly up and perch some- where, it can manage a stressful situation better. We believe that the possibility of controlling the situation better resulted in these individuals being able to maintain optimism, even after a period with increased stress,” says Jose- fina Zidar, who holds a doctorate in ethology from Linköping Uni- versity. It has already been shown that additive stress may have a negative impact on animal wel- fare. This should be considered in animal husbandry, Zidar adds. Even a chicken might suffer the consequences of stress. Photo: Brianna Santellan on Unsplash Workshop: Der vernünftige Grund im Tierschutzgesetz „Niemand darf einem Tier ohne vernünftigen Grund Schmerzen, Leiden oder Schäden zufügen“, heißt es im deutschen Tierschutzgesetz. Doch was ist ein „vernünftiger Grund“? Experten diskutieren diese Frage am 7. Dezember bei einem Workshop an der Universität Münster. Zu Wort kommen die Perspekti- ven des Rechts und der Ethik, der tierversuchsbasier- ten Forschung sowie des Tierschutzes. Das deutsche Tierschutzgesetz regelt insbesonde- re die Tierhaltung, die Tötung von Tieren, Eingriffe und Versuche an Tieren sowie die Zucht von und den Handel mit Tieren. Es stellt die Nutzung von Tieren in vielen Fällen unter einen Genehmigungs- und Erlaub- nisvorbehalt. Dies gilt unter anderem auch für die Genehmigung von Tierversuchen. Besondere Bedeu- tung kommt dabei dem Begriff des „vernünftigen Grundes“ zu. § 1 TierSchG bestimmt, dass niemand „einem Tier ohne vernünftigen Grund Schmerzen, Leiden oder Schäden zufügen“ darf. Nach § 17 wird mit Freiheitsstrafe bis zu drei Jahren oder mit Geld- strafe bestraft, wer „ein Wirbeltier ohne vernünfti- gen Grund tötet“. Im Rahmen einer gemeinsamen Veranstaltung der Rektoratskommission für tierex- perimentelle Forschung der Westfälischen Wilhelms- Universität Münster (WWU) und des Centrums für Bioethik der WWU werden Experten den Begriff des „vernünftigen Grundes“ diskutieren. (31 300' 4)&&5*/( '03 45"#-&4 XXX CSJBO[BQMBTUJDB JU 01"26& (&-$0"5 1305&$5&% 4)&&54 53"/4-6$&/5 1305&$5&% 4)&&54 '-"5 30--4 '03 &9)"645 "*3 $)*./&:4 ):(*&/*$ &/7*30/.&/5 %63"#-& "/% -0/( -*'& 41"/ )*() 3&4*45"/$& 50 "$*%4 "/% 50 "5.041)&3*$ "#3"4*0/ -*()58&*()5 )"--& 45"/% )