Epsilon Archive for Student Projects

Abstract

Farmed mink often perform stereotypic behaviours which is considered to be a sign of reduced welfare. Previous studies have shown that enriched cages can reduce the frequency of performed stereotypies. Most studies on mink in Sweden have been done on adults. The aim of this study was to investigate if larger enriched cages with two or four mink kits reduce stereotypies in mink kits during their growth period in comparison to traditional cages.

In the present study the behaviours of mink kits that were kept in four different treatments at a private mink farm were recorded. Traditional cages with two mink kits were used as a reference and the other treatments consisted of larger cages with shelves with two kits, larger cages with shelves and a plastic cylinder with two kits, and larger cages with shelves with four kits. The behaviours were recorded by one-zero scan sampling with 10-second intervals.

The results showed a statistically significant difference in the frequency of stereotypies between the different treatments. The mink kits that were kept in traditional cages performed more stereotypies than the ones that were kept in enriched cages. The enrichments did not have a significant effect on the activity of the mink kits, but there was a tendency of a difference in total activity between the three different weeks of observation. Both the activity and the frequency of performed stereotypies were higher in the first week of observation, which was probably due to a change in feeding times. The enrichments were utilized frequently and the mink kits that were kept in enriched cages spent a large part (29 – 39 %) of their active time in contact with the enrichments. No significant difference was seen between the different treatments.

The conclusion of this study was that mink kits utilize enrichments to a large extent, which can be the explanation to the significant difference in the frequency of performed stereotypies in the different treatments. Further studies that can show how this kind of early enrichments affects the frequency of performed stereotypies in adult minks during the breeding period are needed.

Farmuppfödda minkar uppvisar ofta stereotypa beteenden vilket anses vara
kopplat till en dålig välfärd. Tidigare studier har visat att berikning av burmiljön
kan leda till en lägre frekvens stereotypier. De flesta studier som gjorts på svenska
minkfarmar är gjorda på vuxna minkar. Syftet med denna studie var att undersöka
om större berikade burar med två eller fyra minkvalpar minskar stereotypier hos
minkvalpar under tiden från avvänjning till pälsning jämfört med standardbur.
I den aktuella studien registrerades beteenden hos minkvalpar som hölls i en av
fyra olika burar på en privat minkfarm. Standardburar där minkvalparna hölls i
par användes som kontrollbehandling och övriga behandlingar bestod av
etageburar med hyllor där minkvalparna hölls i par, etageburar med hyllor plus en
plastcylinder där minkvalparna hölls i par och etageburar med hyllor där
minkvalparna hölls i grupp om fyra. Beteendena registrerades med 0-1
registrering med 10 sekunders intervall.
Resultaten visade att det fanns en signifikant skillnad i frekvensen utförda
stereotypier mellan de olika behandlingarna. Minkvalparna som hölls i
standardburar uppvisade mer stereotypier än de som hölls i berikade burar.
Berikningarna hade ingen signifikant effekt på minkvalparnas aktivitet, men en
tendens skillnad i totalaktivitet kunde ses mellan de tre olika
observationsveckorna. Både aktiviteten och stereotypifrekvensen var högre under
den första observationsveckan, vilket troligtvis berodde på ändrade
utfodringstider. Berikningen utnyttjades i hög grad och de minkar som hölls i
berikade burar ägnade stor del (29 - 39 %) av sin aktiva tid på interaktion med
berikningar. Ingen signifikant skillnad i berikningsaktivitet kunde ses mellan
behandlingarna.
Slutsatsen från denna studie är att minkvalpar utnyttjar berikning i hög grad,
vilket kan vara förklaringen till den signifikanta skillnaden i frekvensen utförda
stereotypier mellan behandlingarna. Det skulle behövas vidare studier som kan
visa hur denna typ av tidig berikning påverkar stereotypifrekvensen hos vuxna
minkar under avelsperioden.