Published online by Cambridge University Press: 01 January 2023
The objective of this study was to test the hypothesis that the body condition of the mink dam, the frequency of dirty nests, frequency of injuries and diarrhoea change significantly with the day of assessment, post-partum, within the data collection period from parturition to weaning, influencing the scores of WelFur at criteria level, but not at principal level or the overall category of mink (Neovison vison) welfare according to the WelFur-Mink protocol. Data from a representative sample of around 120 dams and litters on four farms were collected three to four times in the period stipulated by the WelFur-Mink protocol. WelFur-scores between 0 (worst) and 100 (best) were calculated, aggregated and compared at criteria and principal level. The score for the criterion, ‘Absence of prolonged hunger’ dropped from 86 to 38 after about five weeks of lactation, affecting the principal score ‘Good feeding’, but not by enough to affect the estimated welfare classification. The score for the three other measures also varied with date of assessment but not enough to affect the classification. However, the observed change in the four measures we focused on indicates that a change in the overall WelFur classification can occur if these or other measures change a little more for the better or worse. Possible solutions to this could be reducing the time window for assessment, development of a valid correction factor or to stratify the visits into an early, middle and late visit on a farm within the three registration periods.