By Niels Therkildsen and Ulla Lund Nielsen and edited by Knud Christensen.
The experiment is carried out at the breeding experimental farm 'Syd' owned by the Danish Fur Breeders Association.
It is know among fur farmers that at normal pelting time occur few furs which spot wise damaged fur. The typical places for the damage are at the neck and at the tail tip. Most of this damage are caused either by the animal itself or its cage mate, there are some normal behaivour with licking and cleaning the pelt which somtimes are converted into more agressive gnawing, 'pelt gnaw'. Normally the farmer would not use such animals with damaged fur when he selects the new generation of breeding animals. The present experiment was set up to evaluate if selection for or against animals with pelt gnaw migth have any practical value.
Initial breeding stock .
Before the mating season 1991, 30 males and 100 were selected all having some damage at the neck of their fur. The animals were of the 'Wild mink' colour type. These animals were the base of the selection line named number 63, from the same population the same number of normal breeding animals were selected to form the base of line 64, which is named the control line.
Four generation selection experiment in mink for number of pelt gnaws, line 63 and a control line 64. The experiment has been carried out at the experimental farm 'Syd' in the years 1991 to 1994.
Results of four generations selection.
The frequencies in percentages of pelt gnaws in males in line 63 and 64 at pelting time 1994.
| Degree | of | damage | . | ||
| Line | Free | Little | Mean | Much | |
| Neck gnaw | 63 64 |
47.8 97.7 |
14.2 2.3 |
13.0 0 |
23.9 0 |
| Body gnaw | 63 64 |
71.1 99.2 |
16.9 0.8 |
8.0 0 |
4.0 0 |
| Tail gnaw | 63 64 |
16.9 85.8 |
56.6 13.5 |
16.9 0.8 |
10.0 0 |
The frequencies in percentages of pelt gnaws in females in line 63 and 64 at pelting time 1994.
| Degree | of | damage | . | ||
| Line | Free | Little | Mean | Much | |
| Neck gnaw | 63 64 |
40.2 98.9 |
15.8 0.4 |
20.1 0 |
23.9 0.8 |
| Body gnaw | 63 64 |
67.5 98.5 |
13.4 1.1 |
7.2 0 |
12.0 0 |
| Tail gnaw | 63 64 |
29.7 85.9 |
49.8 13.7 |
10.0 0.8 |
10.5 0 |
Figure. Below can be seen moderate pelt gnaw at the neck (left), back (midt) and tail gnaw (right).