| |
European mink captive breeding
Back
to Content
I. Appendices
Unlike the majority of mustelids, the European mink does not
display delayed implantation. Mating takes place in late March,
April and in early May, but according to the breeding results
at Tallinn Zoo the peak of the heat falls in the second and
third week of April (Figure 2). The gestation lasts 40-43 days
and parturition usually occurs at the beginning of June.
Figure 2. Pro-oestrus, oestrus, occurrence
of copulation and time of
parturition in the European minks kept at Tallinn Zoo
The heat of the female is easily detectable by the size of vulva.
The anoestrus vulva is minute, measuring 2 mm to 4 mm maximum,
usually much smaller. When the female begins to come into heat,
the vulva enlarges over a period of three to four weeks. Its
maximum size may be 10 mm to 10 mm or even more. The colour
of the vulva also changes slightly from pale white during the
anoestrus to pro-oestrus period, to pink-reddish during oestrus.
The size and colouration of vulva can be easily measured and
checked through the handling cage.
Changes in the behaviour may also be a useful indicator of oestrus.
The oestrus female becomes more active and less timid.
More detailed detection of heat can be achieved by histological
investigation of vaginal smears. Samples can be obtained through
vaginal flushing and collected in a small pippette while the
animal is held in a handling cage. A small amount of sterile
water is aspirated into the tip of the pipette. The tip of the
pipette is then inserted approximately 10 mm into the vagina,
the sterile water is injected and immediately aspirated back
into the syringe. The sample is placed on a slide, and can be
stained before examination under the microscope for cornified
cells (Hamilton & Gould, 1940, Travis et.al., 1978, Doboszynska,
1976).
In case of early death of the litter, the potential polyestricity
exhibited by European mink, may still provide the chance to
provide further offspring. Six to nine days after the death
of the young it is possible for the female to come into oestrus
a second time and for copulation to take place again (Moshonkin,
1977).
The reproductive physiology of the European mink is often confused
with that of the American mink, Mustela vison. The latter
displays delayed implantation and its gestation period may be
up to 93 days (Ternovskij, 1977).
The size of the litter varies from 1 to 7. There is a slight
difference in the mean litter size recorded at Tallinn Zoo (2.5),
St.Peterburg Zoo (3.6) and that reported by Ternovskij (3.5;1977).
Since 1960, 113(48.56.9) European minks have been held in captivity,
of which 35% (16.18.5) are wild caught and 64%(30.38.4) captive
bred (1% animals of unknown origin). Dr. D.V. Ternovskij has
kept and bred European mink with the utmost success in captivity,
but unfortunately no data has been made available for the studbook.
Altogether 68(29.35.4) kits have been bred in 25 litters since
1960. At Tallinn Zoo there has been remarkable imbalance in
the sex ratio of in litter(25% of males, 67% of females, 8%
of unknown sex); at St. Petersburg the ratio has been more or
less equal - 52% of males, 43% of females and 5% of unknown
sex. Of all these litters, 32% of the birth were of single kit,
20% two kits, 20% three kits, 8% four kits, 4% five kits, 12%
(???) six kits and 4% seven kits (Fig. 3). This does not reflect
accurately the actual variance in the litter size, as normally
the nest-box can be checked only a week after parturition. Early
disturbance of the mother may result in the killing of young.
Figure 3. Variation in litter size.
The mean litter size in 25 litters is 3.6 kits per litter. This
is in accordance with the figures given in the literature (Ternovskij,
1977)
Appendix 2 
Morphological parameters (Ternovskij, 1977)
-
| |
FEMALE
|
MALE
|
| |
n |
mean |
±
|
|
n |
mean |
±
|
|
| Weight of the animals |
9 |
540.3 |
5.8 |
gr |
17 |
814.6 |
30.4 |
gr |
| Weight of liver |
5 |
29.2 |
3.10 |
gr |
8 |
39.9 |
1.03 |
gr |
| Weight of heart |
5 |
5.0 |
0.30 |
gr |
8 |
6.0 |
0.21 |
gr |
| Weight of lungs |
5 |
7.5 |
1.10 |
gr |
8 |
10.5 |
0.50 |
gr |
| Weight of brain |
5 |
7.9 |
0.40 |
gr |
8 |
9.0 |
0.40 |
gr |
| Weight of pancreas |
5 |
2.6 |
0.60 |
gr |
8 |
2.4 |
0.219 |
gr |
| Weight of left kidney |
5 |
2.5 |
0.10 |
gr |
8 |
3.4 |
0.13 |
gr |
Appendix 3
Change in weight during the post-embryonic development
of the young(Ternovskij, 1977):
| Age in days |
Female
|
Male |
|
n |
mean |
± |
n |
mean |
± |
| 1 |
8 |
8.8 |
0.24 |
8 |
10.0 |
0.22 |
| 2 |
8 |
11.3 |
0.27 |
8 |
11.9 |
0.55 |
| 3 |
8 |
13.6 |
0.43 |
7 |
15.7 |
0.31 |
| 4 |
8 |
16.1 |
0.51 |
7 |
18.6 |
0.37 |
| 5 |
8 |
19.2 |
0.91 |
7 |
22.7 |
0.41 |
| 6 |
8 |
22.7 |
1.00 |
7 |
27.2 |
0.39 |
| 7 |
8 |
27.4 |
1.14 |
7 |
31.5 |
0.52 |
| 8 |
8 |
30.4 |
1.47 |
7 |
35.7 |
0.53 |
| 9 |
8 |
34.2 |
1.17 |
7 |
41.2 |
0.52 |
| 10 |
8 |
38.9 |
1.60 |
7 |
46.6 |
0.80 |
| 11 |
8 |
43.3 |
1.85 |
7 |
52.2 |
1.12 |
| 12 |
8 |
49.5 |
2.30 |
7 |
60.6 |
2.01 |
| 13 |
8 |
53.9 |
2.21 |
7 |
64.8 |
1.71 |
| 14 |
8 |
58.7 |
2.27 |
7 |
69.2 |
1.71 |
| 15 |
8 |
63.6 |
2.55 |
7 |
74.9 |
2.00 |
| 16 |
8 |
70.0 |
2.50 |
7 |
81.8 |
2.39 |
| 17 |
8 |
75.7 |
2.62 |
7 |
87.6 |
2.63 |
| 18 |
8 |
81.3 |
2.85 |
7 |
94.4 |
2.98 |
| 19 |
8 |
89.0 |
2.86 |
7 |
101.6 |
3.36 |
| 20 |
8 |
91.8 |
3.60 |
7 |
106.2 |
3.57 |
| 21 |
8 |
98.5 |
4.30 |
7 |
111.1 |
3.88 |
| 22 |
8 |
105.6 |
5.15 |
7 |
117.0 |
4.20 |
| 23 |
8 |
115.8 |
4.27 |
7 |
126.1 |
4.70 |
| 24 |
8 |
120.7 |
4.43 |
7 |
131.4 |
4.43 |
| 25 |
8 |
125.8 |
4.71 |
7 |
139.6 |
5.80 |
| 26 |
8 |
133.2 |
5.86 |
7 |
149.2 |
7.00 |
| 27 |
8 |
143.3 |
6.15 |
7 |
159.2 |
7,96 |
| 28 |
8 |
153.5 |
6.47 |
7 |
169.2 |
8.94 |
| 29 |
8 |
162.9 |
6.38 |
7 |
179.1 |
9.97 |
| 30 |
8 |
171.7 |
6.69 |
7 |
190.6 |
10.53 |
| 40 |
8 |
274.0 |
8.10 |
7 |
284.4 |
13.42 |
| 50 |
8 |
369.5 |
21.06 |
7 |
438.3 |
21.04 |
| 60 |
7 |
465.1 |
14.24 |
6 |
515.3 |
45.15 |
-
-
-
-
-
-
Appendix 4
3-7 days. The new-born young have no proper
fur and are covered with a fine natal down. The colourof the
dorsal side of body is dark violet; and the ventral side varies
from pinkish-violet to greyish violet. The markings around
the mouth is barely noticeable. The growth of the mane appears
on the neck which reaches a length of 5mm; on the back the
fur is 3mm; and on the stomach and chest 2 mm.
10-16 days. General body coloration is similar to the
previous development period but with the white area around
the mouth becoming more distinguishable.
19-27 days. A more uniform body colouration is developing
with the dorsal side of the body a dark grey or dark violet
and the ventral side approaches a dark violet.
29-40 days. Mane disappears. The juvenile fur darkens
towards the pelage colouration of an adult mink. The appearance
is similar to the young of the European polecat ( Mustela
putorius) until the appearance of the guard hair, after
which the kits resemble the young of the American mink.
The eyes begin to open at 30-36 days of age. At 35-40 days
the young are visually capable of following moving objects.
However, the reaction to moving objects diminishes at 53-54
days of age.
45-80 days. The fur of young resembles more and more
the appearance of adult animal.
At 90 days old the juveniles are indistinguishable from adults.
Appendix 5
Feeding Rations of the Black-Footed Ferret.
-
-
-
| Diet of the BBF at CRC of the National Zoological
Park (Carvalho et. al. 1991) |
|
|
| |
gr |
|
| Commercial mink chow |
1,275 |
62.3% |
| Ground rabbit meat and bones |
675 |
32.9% |
| Blood meal |
50 |
2.4% |
| Bioliver |
50 |
2.4% |
| Total |
2,050 |
100.0% |
| Per one animal in a day |
68.33 |
|
| Each adult ferret received 60 -90 g every day |
|
|
| Diet at Laramie for Mustela eversmanni (Kwiatkowski
1989 in lit): |
|
|
| Liver |
17% |
|
| Fish |
20% |
|
| Bovid stomach |
10% |
|
| Chicken |
25% |
|
| Commercial mink growth ration |
25% |
|
| Black-Footed Ferret diet at Laramie (Kwiatowski
1989 in lit): |
|
|
| 5 days a week |
|
|
| Commercial mink ration |
60% |
|
| Grounded prairie dogs |
40% |
|
| + liver(dry 6%) |
|
|
| 2 days a week hamsters or small rodents |
|
|
| Black-footed Ferret diet at Toronto Zoo (Devison,1992) |
|
|
| Mink chow |
60% |
|
| Ground rabbit with blood-meal,bio-liver and vitamin
E |
40% |
|
| Ad. females lose 15% of their January weight prior
breeding |
|
|
| The weight should be maintained or slightly increased(2-3%) |
|
|
| February - March daily ration 50gr/animal |
|
|
| Ad. males should lose 10% of their January
weights prior to breeding. |
| Daily ration in February, March 62gr/animal |
| Juv. males & females should loose
10% of their February 15th weight prior to March 15th. |
| Obligatory to add to the ration (Kwiatkowski
1989 in lit): |
| Vitamin E 100 IU/kg of ration |
| Zinc 50mg/kg of ration |
| Liver 20%(=6% of bioliver) |
| Weights of BFF and the European mink(Walker
,1991) |
| |
female |
|
male |
|
| Black-Footed Ferret |
809 |
|
1021 |
|
| European mink |
440 |
54% |
739 |
72% |
-
-
Appendix 6
European mink (Mustela lutreola) post mortem report
Studbook No:__________ ISIS No:__________ Local
ID:_________
CaseNo:_________ Zoo:_______________ Age:______
Weight:_______
Date of Birth ___ /___ /___ Date of Arrival ___
/___ /___
Date of Death ___ /___ /___ Date of PM Report ___
/___ /___
___________________________________________________
CarcassCondition:
Fresh / Refrigerated / Frozen / Decomposed / Other______________
Physical Condition:
Normal / Fat* / Emaciated / Other ________________________
Fat*: grade on kidneys:- 1) completely covered with fat
2) some kidney showing
3) fat at poles
4) little or no fat
Comment if obese:____________________________________________
_____________________________________________________
Gross Post Mortem:
| skin /appendages |
digestive |
urinary |
| sensory |
liver |
endocrine |
| muscular |
respiratory |
reproductive |
| skeletal |
cardio-vascular |
nervous |
| adipose |
lympho-ret |
|
Please write:
A - if abnormal ; B - if normal; NE - if not examined
______________________________________________________
Gross Post Mortem Description:
Parasitology:
Arthropods: Y/N Protozoa: Y/N Helminths: Y/N
Results and comments:
________________________________________________________
Microbiology:
Bacteria: Y/N Fungi: Y/N Virus: Y/N Other: Y/N
Results and Comments (please give bacteria code A,B,C etc
and indicate organ of origin):
Antibiogram
Bacteria Code
| |
A
|
B
|
C
|
D
|
E
|
| Chloramphenicol |
|
|
|
|
|
| Kanamycin |
|
|
|
|
|
| Streptomycin |
|
|
|
|
|
| Sulphonamide |
|
|
|
|
|
| Oxytetracyclin |
|
|
|
|
|
| Trimetoprim + S |
|
|
|
|
|
| Gentamycin |
|
|
|
|
|
| Ampicillin |
|
|
|
|
|
| Neomycin |
|
|
|
|
|
| Colistine |
|
|
|
|
|
| Spectinomycin |
|
|
|
|
|
| Flumequine |
|
|
|
|
|
| Others(specify): |
|
|
|
|
|
Code: + = sensitive; + = some inhibition; - = resistant
_______________________________________________________
Haematology:
Blood Smear: Y/N EDTA: Y/N Heparin: Y/N Marrow: Y/N
Results and Comments:
Histology: please indicate which were studied
| oesophagus |
|
kidney |
|
lung |
|
| stomach |
|
adrenal |
|
skin |
|
| intestines |
|
cerebrum |
|
eye |
|
| pancreas |
|
cerebellum |
|
lymph nodes |
|
| liver |
|
spinal cord |
|
Others(specify):- |
| thymus |
|
pituitary |
|
|
|
| thyroid |
|
heart |
|
|
|
| parathyroid |
|
muscles |
|
|
|
| spleen |
|
urinary/bladder |
|
|
|
| testes/ovaries |
|
aorta |
|
|
|
Results and comments:
_______________________________________________________
Probable Cause of Death:
________________________________________________________
Final Conclusion about Cause of Death:
Veterinarian_________________ Signature_______________________
(NB PLEASE ATTACH FULL CLINICAL HISTORY IN ADDITION TO THE
PM REPORT)
Appendix 7
Tissue collection for pathological research
In addition to specimens submitted for diagnostic pathology,
the following tissues should be preserved in 10% buffered
formalin at a ratio of 1 part tissue to 10 parts formalin.
Sections should be no thicker than 1cm. All lesions should
also be included. Tissues should be accurately labelled
and stored at the collection of origin.
During post mortem examination much taxonomic information
can be lost by careless technique. In order to avoid such
problems, please make sure all skin incisions are as straight
and neat as possible. Do not remove any more skin than is
required for diagnostic purposes. Ensure that no skin is
attached to the sets or skeletal muscle if samples of these
tissues are removed. If it is necessary to remove the brain
for examination, please make a straight saggital skin incision
from the crown down the nape of the neck, allowing the skin
to be peeled neatly away from the cranium.
| Tissue |
Area |
Taken
|
| Adrenal |
Entire gland with transverse cut |
YES |
NO |
| Brain |
Sliced longitudinally along midline |
YES |
NO |
| Heart |
Longitudinal section of atrium, venticle and valves
from each side |
YES |
NO |
| Intestines |
Duodenum, jejenum, ileum, ceacum, colon; open along
long axis |
YES |
NO |
| Kidney |
Section of cortex, medulla and pelvis from each
kidney |
YES |
NO |
| Liver |
2 sections from two lobes with capsule and gall
bladder |
YES |
NO |
| Lung |
Sections from several lobes including bronchus
|
YES |
NO |
| Lymph nodes |
Cervical, anterior medisatinal, bronchial, mesentric
and lumbar with a tansverse cut |
YES |
NO |
| Pancreas |
Samples from two areas |
YES |
NO |
| Peripheral nerve |
3cm section of sciatic nerve |
YES |
NO |
| Skeletal muscle |
Cross section of thigh muscle |
YES |
NO |
| Skin |
3cm length of full thickness of abdominal skin
|
YES |
NO |
| Spleen |
Cross section including capsule |
YES |
NO |
| Spinal cord |
Sections from cervical, thoracic and lumbar cord
|
YES |
NO |
| Stomach |
Cardia, antrum and pylorus |
YES |
NO |
Appendix 8
| Reproductive pattern |
Male mean range
|
Female mean range
|
| Age at first copulation |
|
|
|
|
| Age at first conception |
|
|
|
|
| Oestrus |
|
|
4.5 days
|
3-6 days
|
| Gestation period |
|
|
41.5 days
|
40-43 days
|
| Mating period |
|
|
April
|
March April May
|
| Birth period |
|
|
June
|
|
| Litter size |
|
|
3.6
|
1-7
|
| Birth interval |
|
|
|
|
| Reproductive life-span |
|
|
|
|
| Life-time production of kits |
|
|
|
|
|
|
Foundation
Lutreola
