Ahola, L., Harri, M., Kasanen, S., Mononen, J. and Pyykönen, T. 2000. Effect of family housing of farmed silver foxes (Vulpes vulpes) in outdoor enclosures on some behavioural and physiological parameters. Can. J. Anim. Sci. 80: 427-434. Group housing of silver foxes in large housing systems has been claimed to promote the welfare of the species since it provides foxes with the possibility to express species-specific social and locomotor behaviour. In our study, silver foxes were housed in outdoor enclosures in family units consisting of a vixen and her four cubs. Foxes housed alone in traditional fox cages were used as control animals. Light hour activity, rectal temperature during human handling and restraint, activity of the HPA axis, heart and gastrocnemius muscle mass, succinate-dehydrogenase activity in gastrocnemius muscle and mechanical properties of tibia were determined from the foxes. The effect of different housing systems was more pronounced in the cubs than in the vixens, indicating the importance of earlier experiences on animals' performance. Both the increased rectal temperature and the increased activity of the HPA axis especially in the cubs housed in enclosures show that the foxes housed in enclosures had a greater fear level towards man than the foxes housed in cages. Furthermore, the foxes, especially the male cubs, raised in groups may have experienced stress due to social tension. Although the exercise-related parameters may indicate that a larger available space could be beneficial for the foxes' physical endurance, these parameters had no clear correlation with physiological welfare parameters. Les animaux témoins étaient logés dans des cages individuelles classiques. Durant l'expérience, nous avons observé l'activité diurne, la température rectale durant les épisodes de contention et de manipulation par l'homme, l'activité de l'axe HHS (hypothalame-hypophyse-surrénales), la masse musculaire du coeur et du gastrocnemius, l'activité de la succinate-déshydrogénase dans le gastrocnemius et les propriétés mécaniques du tibia. L'effet du système de logement était plus prononcé chez les renardeaux que chez les mères, mettant en relief l'importance d'une expérience antérieure pour les performances des animaux. L'élévation de la température rectale et la plus grande activité de l'axe HHS, surtout chez les renardeaux dans les enclos, montrent que les renards ainsi logés démontraient un niveau de crainte de l'homme plus aigu que ceux logés en cage. En outre, les renardeaux, surtout les mâles élevés en groupe auraient subi du stress lié aux tensions sociales. Bien que les paramètres associés à l'exercice suggèrent qu'une plus vaste surface de logement améliorerait l'endurance physique des renards, ils n'ont pas de corrélation nette avec les paramètres de bien-être physiologique.

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Ahola, L., Harri, M., Mononen, J., Pyykönen, T. and Kasanen, S. 2001. Welfare of farmed silver foxes (Vulpes vulpes) housed in sibling groups in large outdoor enclosures. Can. J. Anim. Sci. 81: [435][436][437][438][439][440]. The aim of the present study was to evaluate the effects of housing farmed silver foxes in large outdoor enclosures with less abundant human contacts on some behavioural and physiological welfare parameters. Farmed silver fox cubs were housed either singly in traditional fox cages or in sibling groups in enclosures. Mass of adrenals, serum cortisol level after adrenocorticotrophic hormone (ACTH) administration and stress-induced hyperthermia, as well as 24-h activity measures and the number of bite scars, were used to draw conclusions on the welfare effects of housing farmed silver foxes in the two experimental housing systems.The housing system had significant effects neither on the serum cortisol level after ACTH administration nor on the mass of adrenals. This result shows that intra-group social tension and non-habituation to humans, both leading to increased long-term stress in foxes housed in large outdoor enclosures, can be partly overcome by, respectively, altering the group composition and keeping the cubs for a longer time in cage conditions with close human contact. However, a large number of bite scars and increased stress-induced hyperthermia (SIH) in the foxes housed in enclosures, indicating an acute stress response to the presence of humans, may not be overcome. Furthermore, the 24-h activity rhythm changed in the foxes housed in large enclosures resembling, especially in November, the nocturnal activity pattern of the wild red fox, indicating that the foxes in enclosures became at least to some extent feral. Le type de logement n'a aucune incidence sensible sur la concentration de cortisol dans le sang après administration d'ACTH ni sur la masse des surrénales. Les résultats révèlent qu'on peut atténuer partiellement le plus grand stress à long terme qu'éprouvent les renards gardés en semi-liberté consécutivement à la tension sociale dans le groupe et au côtoiement des humains en modifiant la composition du groupe et en gardant les petits en cage plus longtemps, à proximité des humains, respectivement. Néanmoins, on pourrait ne pas surmonter le nombre accru de cicatrices venant des morsures ni la plus forte concentration de SIH résultant du stress plus intense causé par la présence des humains. Par ailleurs, le rythme circadien des renards élevés en semi-liberté subit une modification, de telle sorte qu'il se rapproche du schéma d'activité nocturne du renard roux à l'état sauvage, en novembre surtout, signe que les animaux retournent au moins en partie à l'état sauvage.

The present study included two procedures, both aimed at improving animal welfare: early handling and changing the social conditions of the animals. Production and welfare related parameters as well as behaviour were assessed in blue fox (Alopex lagopus) cubs who were either handled or not before weaning, and housed after weaning either in pairs or in six-animal groups. The effect of the larger group size was observed in the larger number of bite scars in the female cubs housed in six-animal groups. Furthermore, the group size seemed to affect the performance of foxes most clearly in the late autumn when intra-litter aggression was observed during the feeding test. On the other hand, early handling had only short-term positive effects on the performance of the foxes but later transpired to have a negative impact on the stress profile of these animals.