Foot condition and Welfare in blue foxes

Abstract

Condition of feet is related to health and welfare in farm animals. Pronounced bending of forelegs is in blue foxes (Vulpes lagopus) an escalating phenomenon which has been recognized on farms and measures to understand its background, etiology and welfare implications has been initiated. The purpose of the present study was to clarify to which extent feeding intensity (ad libitum vs restricted) influences on foot condition and welfare in growing-furring blue foxes. The subjects were 200 sibling pairs divided into two groups: (1) Ad libitum (Ad Lib) and (2) Restricted feeding (Restr). Feeding arrangements were started on July 29. Restricted portion was raised from Sept 22 onwards on ad libitum level. The statistical analyses were done by using the Fishers exact test, Tukeys test, Spearman correlations, Logistic regression and Mixed model of the SAS software for Windows version 9.4. Initial body weights of groups were similar. From Aug 11 onwards body weights of Ad Lib remained significantly (P<0.001) higher compared to Restr ones during the restricted period. Thereafter, compensatory growth occurred in Restr groups (P<0.05). Final body weights at pelting (Dec 8) were significantly higher (P<0.001) in Ad Lib than Rest animals. Body condition score (BSC) followed the same pattern. Foot condition was better in Restr than Ad Lib both at the end of restricted period as well as at pelting. Moving difficulties, patellar luxation and veering were slight in both groups. Angulation of rear angle was more pronounced in Ad Lib animals (P<0.001). Weight of right adrenal gland was significantly heavier (P<0.01) in Ad Lib than Restr groups. Weight of thymus was heavier in Restr than Ad Lib animals (P<0.01). Animals in Restr group, particularly females, used platforms typically significantly more than animals in Ad Lib group (P<0.01). The conclusions of the present study are; (1) that foot bending is the best method to evaluate foot condition even in large, fat animals. (2) Moving difficulties are most common in heaviest animals. (3) Excessive obesity declines platform use. (4) Prolonged intensive feeding may jeopardize foot condition and welfare.