Forskning
Abstract
To an investigation on the use of fibre in low and high
concentrated mink feed in the winter period, we used tree groups of
175 black mink females each. The control group (Kon) was feed a low
concentrated feed, to that feed we added 15 % fibre (Fib1), to
compare we added 15 % fibres to a high concentrated feed
(Fib2).
If females are feed the same amount of energy, an addition of
fibres and water to the feed, will increase time with feed on the
cage. This is due to both an effect of bigger feed volume and that
fibres increase the feeling of satiety by increasing the filling of
the digestive system. Stereotypic behaviour is reduced
significantly by using low energy feed and thereby a bigger feed
volume. However females who reduce there activity have a bigger
body score before flushing, and had a higher number of dead kits at
birth.
Clausen, T. N., Hansen, S.W & Sandbøl, P.
2010. Low energy feed with barley hulls reduces
stereotypies in the winter period. Annual Report 2009, 7-15, Danish
Fur Breeders Research Center, Holstebro, Denmark.
Abstract
There is evidence from several species (e.g. poultry) that
selection can contribute to reducing aggression in groups, and
selection thus could be one way of reducing aggression in groups of
mink in group housing. On this background, a selection experiment
was started, aiming at reducing the number of bite marks on the
skin side. This study describes variation in bite marks in the
first generation. The study includes evaluation of bite marks on a
total of 640 mink in group housing and 289 of their full sibs in
standard cages (two animals).In group housing significantly more
bite marks are observed than on the corresponding full sibs in
standard cages. In addition, there seems to be a weak relationship
between number of bite marks in group housing and standard cages.
In group housing the females are generally more bitten than males,
though the most bitten male has on average more bite marks than the
least bitten female. A higher correlation between number of bite
marks are observed between animals of the same sex (the two males
and the two females) than between sexes in group housing. This
indicates that bite marks to a large extent is due to fights within
sexes. A large variation between full sibs/cages was found in the
number of bite marks. This indicates that genetic differences are
an important factor contributing to the number of bite marks.
Selection for reduced number of bite marks continues in the coming
years.
Berg, P. & Møller, S. H. 2010. Possibilities
for selecting for reduced aggression in group-housing. Annual
Report 2009. 17-22. Danish Fur Breeders Research Center, Holstebro,
Denmark.
Abstract
The inheritance of black palate colour has been investigated in
more than 1000 F2 animals derived from a cross between Wild-mink
and "short nap" Black mink. A statistically significant
relationship was found between the palate colour in parent and
offspring. In addition was found a statistically significant
relationship between the palate colour and a gene marker Mvi1950;
but the inheritance of palate colour could not be explained by
segregation of the alleles in one locus alone. Absolutely no
relationship was found between the colour of the palate and coat
colour scored from one to seven.
Christensen, K., Anistoroaei, R., Fredholm, M. &
Nielsen, V. H. 2010. Inheritance of black palate in mink.
Annual Report 2009, 23-25. Danish Fur Breeders Research Center,
Holstebro, Denmark.
Abstract
With special emphasis on the level of relatedness (R) within
mink color types (Neovison vison) originating from different mink
farms in Denmark we present here the results from a microsatellite
analysis study. Large differences were observed in level of R (R
range: 0.017-0.520) and in genetic distance (FST range:
0-0.29) between strains and farms. Moreover, we correlated the
level of R and breeding result for individual mink populations and
found a very strong and highly significant negative correlation
between these two parameters (R2=0.60, p<0.001). To
our knowledge this is the first time that such a correlation has
been demonstrated in mink from commercial mink farms. As a result
we suggest using microsatellite or an alternative type of markers
e.g. VeraCode, SNPlex and Fluidigm EP1 systems, which can be
utilized to evaluate level of R in mink strains with reproductive
problems and apply information from genetic markers when e.g.
buying in new breeding animals in order to optimize fitness.
Alternatively this technique could also be employed in order to
obtain heterosis within color types applying the genetic variation
found within a color type. We hope that this new molecular genetic
information can be applied in practical mink farming in the
future.
Larsen, P. F., Bækgaard, H., Sønderup, M., Møller, H. H.,
Hansen, B. K., Nielsen, V. H., Demontis, D., Loeschcke, V. &
Perfoldi, C. 2010. Level of inbreeding and genetic
distance in Danish farm mink (Neovison vison). Annual report 2009,
27-31, Danish Fur Breeders Research Center, Holstebro, Denmark
Abstract
To continue the investigations on the need of protein, fat,
carbohydrates and amino acids in the gestation period (April 4 to
April 26) we used 6 groups each consisting of 134 brown mink
females. The females were fed with feed from the local Feedkitchen
until April 6, thereafter the protein content was varied in the
groups from 35 to 45 percent of metabolisable energy from protein
(MEp) fat was varied from 40 to 55 MEf and carbohydrates was varied
from 10 - 20 MEc. After April 26 these females had 30 MEp until day
28 in the nursing period, thereafter feed from the local feed
kitchen was used. Only females giving birth between April 26 and
May 5 was included in investigation.
The results showed no significant difference between any of the
groups, so the current recommendations for protein and amino acids
in the gestation period will not be changed.
Clausen, T. N. & Sandbøl, P. 2010. Protein to
mink in the gestation period. Continued investigations, Annual
Report 2009, 33-37, Danish Fur Breeders Research Center, Holstebro,
Denmark.
Abstract
To an investigation on optimal feeding of mink kits in the early
growing period, we used 7 groups consisting of 135 wildtype mink
females and their kits. Until the kits were 28 days we used feed
kitchen feed, after that feed with different amounts of protein
were used until 12 weeks of age.
The results confirmed what we have found earlier. Kits in the
period 4 to 8 weeks, need 45 percent of the metabolisable energy
from protein (MEp) combined with a low amount of carbohydrates (10
and 15 MEc). In the period 8 to 12 weeks, the body weight increase
is equally good in kits fed 35 MEp and 45 MEp. Further the body
weight increase is reduced with increasing carbohydrates in that
period. Kits feed 30 MEp from 4 to 12 weeks are smallest at
pelting. The amino acid recommendations for that period, seems to
be sufficient.
Clausen, T. N. & Sandbøl, P. 2010. Mink kits,
optimal growth and good skin size. Annual Report 2009, 39-44,
Danish Fur Breeders Research Center, Holstebro, Denmark.
Abstract
To the investigation of increasing amounts of glycerol 0 - 2 - 4
- 6 - 8 percent to mink kits in the growing period, we used 5
groups of 132 wildtype mink kits each. The results showed that we
can use up to 8 % glycerol instead of 8 % cornstarch, with
reservations to changes in feed consistency. Glycerol should be
analysed for Na and methanol before use. The skin quality was best
at 8 % glycerol and no cornstarch, also it seems that glycerol
reduces the liver fat content.
Clausen, T. N. & Sandbøl, P. 2010. Glycerol in
mink feed in the growing- furring period. Annual Report 2009,
45-50, Danish Fur Breeders Research Center, Holstebro, Denmark.
Abstract
To investigate the effect of L-met or DL-met to mink in the
growing-furring period, we used 7 groups of 132 wildtype male- and
female mink kits each. To a control feed with low methionine we
added L-met or DL-met up to a calculated content of 0.10, 0.13 and
0.16 g digestible met / 100 kcal. The heaviest male kits and the
longest skins at pelting were seen in the group with the highest
addition of DL-met. From an analysed content of 0.14 g met / 100
kcal and more the skin size and pelt quality was good, and existing
norm is adequate. Further it seems that the animals are able to use
some of the D form of methionine, as an addition of DL-met in twice
the amount of L-met gave better results.
Clausen, T. N. & Sandbøl, P. 2010.
Investigation on the effect of L- and DL- methionine to mink in the
growing-furring period. Annual Report 2009, 51-56, Danish Fur
Breeders Research Center, Holstebro, Denmark.
Abstract
To find the optimal level of phe+tyr for body growth and pelt
colour and to find the importance of Fe, Cu and Zn for pelt colour,
we used 5 groups of 142 black male and female mink kits each, and 2
groups of 122 wildtype male and female kits each. To a control feed
with a low content of phe+tyr (0.41 g digestible phe + tyr / 100
kcal) we added phe + tyr up to a total content of 0.47 vs. 0.55 g
digestible phe + tyr / 100 kcal. Further we had two groups with and
addition of chelated minerals, cupper (Cu), zink (Zn) and iron (Fe)
in two levels to the control feed.
The results showed a tendency towards the lowest weight at the
lowest phe + tyr level and a tendency towards the darkest skins at
the highest level, both in black and wildtype mink kits. Increased
addition of minerals in the amounts used here gave a better body
growth, there were no significant difference in skin length and
pelt quality, but a tendency towards lower skin quality, and darker
colour at the highest addition. The liver fat content was highest
at the highest addition of chelated minerals. There was a tendency
towards an increased liver mineral content when the feed mineral
content increased, but no significant increase.
Clausen, T. N. & Sandbøl, P. 2010.
Investigation on the importance of the aminoacids phenylalanine
(phe) and tyrosine (tyr), and the minerals iron (Fe), cupper (Cu)
and zink (Zn) on pelt colour in black and brown mink. Annual Report
2009, 57-65, Danish Fur Breeders Research Center, Holstebro,
Denmark.
Abstract
A dark and light sample of Glycerol was compared in a
digestibility trial. The light Glycerol contained slightly more
crude protein, fat, ash and salt (percentage of dry matter) and
thus slightly less calculated crude carbohydrates than the dark
sample. A discrepancy hydrates in the diets. The apparent
digestibility of carborhydrates in both samples of Gly- cerol was
93 %.
Schulin-Zeuthen, M & Sandbøl, P. 2010.
Apparent digestibility of Glycerol in mink. Annual Report 2009,
67-70. Danish Fur Breeders Research Center, Holstebro, Denmark.
Abstract
Thirty-two pairs of male mink kits were allocated to four
different diets four weeks post partum. The kits were weaned when
they were 5-6 weeks old. The apparent and true digestibilities of
the diets were calculated from quantitative collection of faeces
when the kits were 6, 9 and 12 weeks old. The diets contained
either 30% or 45% of the metabolisable energy (ME) from protein and
15% or 25% of ME from carbohydrate. The diet codes were HPHC (high
protein, high carbohydrate; 45:25), LPHC (low protein, high
carbohydrate; 30:25), HPLC (45:15) and LPLC (30:15). The apparent
digestibility of nitrogen and amino acids was significantly lower
on both LP than on the HP diets. The true digestibility on the LPHC
diet was the same as on the HP diets except for methionine, leucine
and valine, which were lower. The true digestibility of the LPLC
was significantly lower than that of the other diets except for
histidine. Both apparent and true digestibility of nitrogen, fat,
energy, and amino acids decreased with age.
Hellwing, A. L. F., Hansen, N. E. og Tauson, A.-H.
2010. Apparent and true digestibility of nitrogen, fat,
energy, and amino acids. Annual Report 2009. 71-78. Danish Fur
Breeders Research Center, Holstebro, Denmark.
Abstract
Two groups of 8 weeks old mink kits were offered a synthetic
diet containing 17.5 % MEp corresponding to 50 % of the protein
requirement of the kits. In one of these groups, soy lecithin
replaced 5 % of the dietary fat fraction. A control group was kept
under normal farm conditions offered a regular feed kitchen diet.
The two restricted groups maintained weight (lecithin group) or
loosed weight (synthetic control) during the 11 days of
restriction. 2 weeks after conclusion of the restriction period,
live weight of all mink kits were the same and therefore the two
restricted groups was able to compensate growth.
Schulin-Zeuthen, M. & Sandbøl, P. 2010.
Compensatory growth in mink kits (Mustela vison) following
reduced protein intake after weaning. Annual Report 2009, 79-83,
Danish Fur Breeders Research Center, Holstebro Denmark.
Abstract
The aim of the project was in a challenge model to measure the
susceptibility of post weaning diarrhoea in mink kits. The kits
were from litters fed a kit diet (high digestibility) and an
ordinary farm diet, respectively. The project was performed during
the first 7 days after weaning. The mink kits were orally
challenged with coli bacteria (Escherichia coli O68) on
day 1 and 2 after weaning. The frequency of mink kits with
diarrhoea was not affected by the composition of the diets. The
body weight and the body growth were not affected by the diet
composition and the challenge with bacteria. The number of
erythrocytes, the content of haemoglobin and the haematocrit value
in the blood were higher in kits fed kit diet than in kits fed farm
diet. The number of leucocytes and neutrophils in the blood and the
plasma content of the acute phase proteins haptoglobin and
fibrinogen were lower in kits fed kit diet than in kits fed farm
diet. The thickness of the muscles in the last part of the small
intestine, the area of the mucins on villi in the small intestine
and the area of the mucins in the crypts in the last part of the
intestine were higher in kits fed kit diet than in kits fed farm
diet.
Damgaard, B.M., Hedemann, M.S. 2010.
Susceptibility of post weaning diarrhoea in mink kits - Effects of
diet composition. Annual report 2009, 85-90. Danish Fur Breeders
Research Center, Holstebro, Denmark.
Abstract
Previous epidemiological studies have shown an association
between presence of mink astrovirus and pre-weaning diarrhoea in
affected as compared to non-affected farms. In order to enable
investigations on the spread of astrovirus infections in mink and
to monitor production of antibodies following immunization or
challenge experiments, a serological tool was needed. An indirect
ELISA was developed using recombinant capsid protein of mink
astrovirus as antigen. Plates were coated with capsid protein and
incubated with the sera diluted 1:100. As secondary antibody, a
horseradish peroxidase-labeled mouse anti-mustelid IgG was used.
Development of the reaction was done with tetramethylbenzidine as
substrate. The readings were done by measuring the optical density
(OD) at 450 nm. This ELISA has been used in different studies, such
as for determination of immunogenicity of the capsid protein, and
detection of antibodies in sera from farms with and without
clinical history of greasy kits. Production of specific antibodies
could be detected with the ELISA in mink immunized with the
complete and with two short variants of the capsid protein. Also,
by means of this ELISA it could be demonstrated that antibodies to
mink astrovirus are commonly present in farms reporting the wet
kits syndrome. However, also on farms without wet kits antibodies
to mink astrovirus could be detected, albeit with lower
titres. It is concluded that the developed ELISA is a suitable tool
for detection of antibodies against mink astrovirus. Also, the
ELISA supports the evidence that infection with astrovirus is
common in mink farms, and indicates that different presentations,
from subclinical to overt clinical manifestations appear in
different farms.
Ullman, K., Baule, C., Hammer, A.S., Hammer- Jensen, T. b>&
Czifra, G., 2010. Evaluation of an ELISA for detection of
antibodies to mink astrovirus. Annual report 2009, 91-96. Danish
Fur Breeders Research Center, Holstebro, Denmark
Abstract
Investigation on the courses of death among kits from 828
litters in the period from birth to August the first. The results
showed that we loose many kits in connection with birth. Around ½ a
kit per litter is stillborn. Since especially the fat females loose
kits, feeding and control of body score in the winter and pregnancy
period should be optimised. The rest of May only a few kits die,
but when they start to eat, around 4 weeks of age, some kits gets
diarrhoea and become unthrifty. To avoid that management at the
farm is very important, good bedding materials, hygiene, optimal
food quality, water supply and immediate treatment if there is
diarrhoea. If those conditions are not optimal we further risk
cannibalism among the kits. From the middle of June bladder
infections is the main problem, the feed in that period should have
acidifying properties and the water supply should be
optimised.
Clausen, T. N., 2010. Kit death from birth to August the
first.Annual Report 2009, 97-103. Danish Fur Breeders Research
Center, Holstebro, Denmark.
Abstract
To an investigation on the importance of the feed for urine pH
we used 2 x 36 wildtype male and female mink kits. Urine samples
for pH measurement were taken after a fasting period, and at
different times after feeding. The results showed, that fasting
urine pH is in the area 6.05 to 6.50. Consumption of feed influence
the urine pH dependent on feed composition and amount. Urine pH is
investigated 4 hours after feeding. If there is feed on the wire
all day long, urine pH will not reach fasting level unless the feed
composition act in direction of low urine pH or unless substances
that lower urine pH is added. It is recommended that urine pH 4
hours after feeding is in the area 6.0 to 6.4.
Clausen, T. N., 2010. Importance of feed consumption for urine pH,
Annual Report 2009, 105-109. Danish Fur Breeders Research Center,
Holstebro, Denmark.
Abstract
Mink were inoculated with two different Canine distemper viruses
(CDV) - a Danish (DK91) virus strain and an American (Snyder Hill)
virus strain. DK91 represents a circulating European wildtype
genotype, while the Snyder Hill strain represents the American
genotypes isolated before 1960. Clinical and paraclinical
investigations of the mink were performed after inoculation. The
wildtype CDVs investigated provoked marked virulence differences.
The Danish wildtype showed a mildly virulent course in our natural
host model, in contrast to the acute, severe disease outcome in the
Snyder Hill challenged mink.
Furthermore, we investigated if DNA vaccine consisting of the genes
from vaccine strains induced cross-protection against circulating
European CDV. Our results indicate that DNA vaccine-induced
immunity protected the mink against disease development. Further
work on DNA vaccines against circulating wildtype CDVs could lead
to new and safer strategies to control and to prevent
distemper.
Nielsen, L., Søgaard, M., Jensen, T. H., Karlskov-Mortensen, P.,
Andersen, M. K., Jensen, T. D., Aasted, B., and Blixenkrone-Møller.
2010. Investigation of wildtype canine distemper virus and DNA
vaccination in mink. Annual Report 2009, 111-118, Danish Fur
Breeders Research Center, Holstebro, Denmark
Abstract
Canine distemper virus and the closely related phocine distemper
virus have an overlapping host range and both have induced disease
among terrestrial and marine carnivores. We have characterized the
distemper virus among the wildlife in Denmark from 2000 to
2003.
We have isolated viral RNA from the new wildtype CDVs, performed
nucleic acid sequencing and determined the relatedness of the
wildtypes. We found that the isolated virus from the investigated
terrestrial carnivores (mink, badger, European polecat, beech
marten and pine marten) were canine distemper virus, which was
phylogeny separated from virus isolated from diseased seals. Our
results revealed no direct epidemiological link between the two
distemper viruses isolated from distemper cases among land-living
carnivores and the marine carnivore.
Nielsen, L., Jensen, T. H., Hammer, A. S., Banyard, A. C., Barrett,
T., Blixenkrone-Møller. 2010. Phylogeny investigation of new
wildtypes of canine distemper virus. Annual Report 2009, 119-125.
Danish Fur Breeders Research Center, Holstebro, Denmark.
Abstract
DNA vaccination is a promising vaccination strategy with
potentials for inducing immunity in young individuals because of
the possibility to overcome maternally derived antibodies. However,
the capacity of a DNA vaccine to induce immunity against CDV in
young mink without maternal antibodies has so far not been
described. In this study young mink kits (n=8) were vaccinated with
DNA plasmids encoding the viral haemagglutinin protein (H) of
Canine distemper virus (CDV). Virus neutralising antibodies (VN)
were induced after 2 immunisations and after the third immunisation
all kits had high VN antibody titres which remained for more than 4
months until challenge inoculation. The DNA vaccinated mink were
protected against viremia, lymphopenia and clinical disease after
challenge inoculation with a recent wild type strain of CDV. The
T-cell immune response of the vaccinated mink was boosted by
challenge inoculation indicating that the vaccine primed a memory
response.
Jensen, T. H., Nielsen, L., Aasted, B. & Blixenkrone-Møller, M.
2010. DNA vaccination protects mink kits against distemper. Annual
Report 2009. 127-133. Danish Fur Breeders Research Center,
Holstebro, Denmark.
Abstract
Necrotizing and eosinophilic myopathia was first observed in
farmed mink kits in Denmark in August 2008. During the following
months the disease was identified on altogether 13 farms in the
south-western part of Denmark. In 2009 outbreaks appeared on 6
farms. A total of 202 mink kits with myopathia were included in
this investigation. Histopathology showed necrotizing myopathia
with fragmentation, hyalinization and atrophy of muscle fibres.
Inflammatory cell infiltrations varied from primarily eosinophilic
to predominantly mononuclear infiltrations. Differential count of
blood samples from two mink showed increased numbers of
eosinophilic cells. The disease affects mink of all colour types,
which makes it unlikely to be inherited, though there may be
genetic factors affecting the course of disease. Testing was
conducted to determine the cause of the disease, including tests
for specific viral diseases (canine distemper, Aleutian mink
disease), tests for protozoa (Toxoplasma gondii, Neospora caninum),
bacteria (general aerobic and anaerobic culture) and toxines
(Narasin, Monensin, Salinomycin, Lasalocid, melamin) and blood
analyses. The preliminary results are inconclusive and further
investigations are necessary to identify the cause of the
disease.
Hammer A. S., Jensen, T.H., Salomonsen, C. M.,
Harslund, J.L.F., Christensen, L. R., Chriel,
M., Clausen, T. 2010.
Outbreak of masticatory myositis in farmed mink. Faglig
Årsberetning 2009, 135-140. Pelsdyrerhvervets Forsøgs- og
ForskningsCenter, Holstebro, Danmark.
Abstract
Nest box design and type of nesting material affect kit survival
and wellbeing. In this pilot study, 12 farms were involved. As
background material in the nest was, Easy Stroe (trade name for
heat-treated, forage harvester wheat straw), compared with shavings
and short cutted barley straw were studied. As nesting material the
long cutted barley straw was compared with the short cutted barley
straw and the wood shavings. It was also investigated whether
reduced nest box size had an impact. The Number of living and dead
pups from 2 to 5 days of age and the number of living pups at 3 to
4 weeks of age were recorded. Easy Stroe compared to shavings as
bottom material, showed a statistically significant difference in
favour of Easy Stroe on a total number of pups at birth, the number
of living pups at birth and the number of puppies at the second
count.. There was no significant difference for kit loss between
the first and second counts.
The study points to the importance of choice of nesting material
and design. There was found a statistically significant difference
of 0.20 kits/female for Easy Stroe over shavings, measured as
living pups at 3 to 4 weeks of age. Moreover, future areas of focus
will be discussed.
Sønderup, M., Bækgaard, H., Larsen, P. F. & Clausen, T. N.
2010. Importance of nest box size and material, for litter
size, a pilot study. Annual Report 2009, 141-146. Danish Fur
Breeders Research Center, Holstebro, Denmark.
Abstract
In an attempt to reduce the loss of feed under the cages in
early July, we placed metal plates in the bottom of 155 cages with
wildtype mink kits. Feed consumption and body growth was registered
in this group and in a control group (155 cages) without
plates.
Feed consumption in early July can be reduced from about 9 % to
about 2 % by using metal plates, and body growth tended to
increase. The loss of food was reducer gradually to around 1.2 % in
early August in cages without plates. However there are great
variations from year to year depending of feed consistency,
temperature, weather etc. By removing the plates in early September
problems with lumps in the pelt was avoided.
Clausen, T. N., Blæsbjerg, M. & Sandbøl, P. 2010. Reducing feed
loss in the growing period by metal plates in the cage. Annual
Report 2009, 147-150. Danish Fur Breeders Research Center,
Holstebro, Denmark.
Abstract
The purpose of this investigation was to follow feed consumption
and body weight growth in early and late borne mink kits. To the
investigation we used one male mink kit from each of the 58 first
borne wildtype litters (borne April 22 to April 26) and from each
of the 52 latest borne wildtype litters (borne May 6 to May
14).
Body weight in early and late borne kits was equal at the same age,
and the total food consumption from July to pelting was equal. In
the beginning of the growing period, late borne kits eat less than
early borne, but from September late borne kits eat more. Pelt
quality, body length, skin length and body condition at pelting
were equal.
Clausen, T. N. & Sandbøl, P. 2010. Importance of birth date on
kit growth in the growing period. Annual Report 2009, 151-154.
Danish Fur Breeders Research Center, Holstebro, Denmark.