Showing papers on "Mink published in 1989"

Defective virus is associated with induction of murine retrovirus-induced immunodeficiency syndrome

Abstract: C57BL/6 mice infected with a mixture of murine leukemia viruses (MuLV) develop a syndrome characterized by lymphoproliferation and profound immunodeficiency. Analyses of this viral mixture (LP-BM5 MuLV) showed that it includes replication-competent ecotropic and mink cell focus-inducing MuLV and defective viruses with genome sizes of 3.8-6.5 kilobases. The ecotropic and mink cell focus-inducing MuLV biologically cloned from the mixture did not induce disease, whereas viral preparations containing the ecotropic MuLV and 4.8-kilobase defective virus were active. Cells producing the 4.8-kilobase defective virus expressed an unusual gag-encoded polyprotein of Mr 60,000.

Influence of dietary fat source on the body fat composition of mink (Mustela vison) and blue fox (Alopex lagopus)

Abstract: The influence of dietary fat source on the fatty acid composition of mink and blue fox fat in different parts of the body was studied. In addition, seasonal changes in the fatty acid composition of the skin and subcutaneous fat were determined. The dietary fat sources used in the experiments were beef tallow, mink fat, capelin oil, soybean oil and rapeseed oil. The fat level supplied by the diets was 20% in the dry matter of feed. Skin and subcutaneous fat samples were taken in August and November. Body fat samples were collected from the groin, around the kidneys and from the liver in November. Raw skin samples were taken after skin grading in January. The fatty acid compositions of the fat samples studied all markedly reflected the fatty acid profile of the respective dietary fat source. Blue fox fat was found to be more saturated than the fat of minks fed the same diet. The amount of unsaturated fatty acids in the skin and subcutaneous fat increased towards winter. This increase was more notab...

Passive transfer of antiviral antibodies restricts replication of Aleutian mink disease parvovirus in vivo.

Abstract: When mink kits were infected neonatally with a highly virulent strain of Aleutian disease virus (ADV), 100% of both Aleutian and non-Aleutian genotype mink died of interstitial pneumonia characterized by permissive ADV infection of alveolar type II cells. Treatment of infected kits with either mink anti-ADV gamma globulin or mouse monoclonal antibodies against ADV structural proteins reduced mortality by 50 to 75% and drastically reduced the severity of clinical signs. Interestingly, mink kits that survived the acute pulmonary disease all developed the chronic form of immune complex-mediated Aleutian disease. Thus, the antibodies directed against ADV structural proteins were capable of modulating the in vivo pathogenicity from an acute fulminant disease to a chronic immune complex-mediated disorder. The mechanism of this modulation was examined by strand-specific in situ hybridization. We found that the number of ADV-infected type II cells was the same in both untreated and antibody-treated kits. However, in the treated kits, viral replication and transcription were restricted at the cellular level. These data suggested that antibodies prevented acute viral pneumonia by restricting the intracellular level of viral replication and that the relevant antigenic determinants were contained within the viral structural proteins. The restricted levels of viral replication and transcription seen in antibody-treated mink kits resembled the levels observed in infected adult mink and suggested a role of antiviral antibodies in development of persistent infection and chronic immune complex disease.

Reproduction and fertility in the mink (Mustela vison)

Abstract: Page Introduction 413 The hypothalamus, pituitary and pineal 414 The hypothalamic\p=n-\pituitaryunit 414 Anatomy 414 Secretion of hormones 414 The pineal gland 416 Anatomy and secretion of hormones 416 Reproductive biology of the female 416 Oogenesis and ovulation 416 The phenomenon of delayed implantation 419 Fertilization, gestation and parturition 421 Other studies on the reproductive biology of the female 422 Reproductive biology of the male 422 Testicular development and spermatogenesis 422 Photoperiodic regulation of male reproduction 425 Other aspects of male reproductive biology 426 Reproductive problems in the female 427 Reproductive problems in the male 429 References 431

Infection studies in mink with seal-derived morbillivirus.

Abstract: Morbillivirus derived from diseased harbour seals (Phoca vitulina) has characteristics of acute virulent canine distemper virus infection in mink. The infection induced a disease resembling the acute systemic and nervous form of canine distemper.

Detection of intracellular canine distemper virus antigen in mink inoculated with an attenuated or a virulent strain of canine distemper virus.

Abstract: Using an indirect immunofluorescence technique, the distribution of viral antigen in various tissues and blood mononuclear leukocytes was studied in wild mink, either vaccinated with an attenuated vaccine strain of canine distemper virus (CDV) or experimentally inoculated with the virulent Snyder-Hill strain of CDV. Viral antigen was detected in cells of the lymphoid system 6 to 12 days after vaccination. From 2 to 3 days after inoculation with the virulent strain, CDV antigen was demonstrated in cells of the lymphoid system and, during the incubation period, the antigen had spread to the epithelia and brain at days 6 and 12, respectively. In clinical cases of acute fatal canine distemper, the viral antigen was detected in a wide variety of tissues, including the cells of the lymphoid system, epithelial cells of skin, mucous membranes, lung, kidney, and cells of the CNS. The diagnostic importance of CDV antigen detection is discussed on the basis of these findings.

Mating systems and reproduction of mink

Abstract: The effects of different mating systems on some reproductive traits were studied in 1515 mink females. Most females were of standard type, a few of pastel type, and the investigation comprised yearlings and older females. The systems evaluated were mating once (1), mating on two consecutive days (1+1) and mating twice with a 9 day interval between matings (1+9). The matings were started on various fixed dates between March 7 and March 25. The project was extended to include histological studies of ovaries from unmated mink sacrificed at different dates during the breeding season. Furthermore, eggs, embryos and foetuses were recovered and counted after various periods of gestation The readiness to mate increased steadily during the mating season. Overall acceptance rates on the first test day were 86% for older females and 80% for yearlings. These high rates indicate that the unmated female does not undergo cyclic heat periods; but when she has come into heat she is ready to mate at any time durin...

Suspected Aleutian disease in a wild otter (Lutra lutra)

Abstract: Clinical and pathological observations of a naturally occurring disease in a British wild otter (Lutra lutra) are reported. Systemic lymphoreticular proliferative changes with plasmacytosis, glomerulonephritis, arteritis and biliary hyperplasia closely resembled the pathological changes in Aleutian disease of mink (Mustela vison). Feral mink provided a possible source of infection.

Geographic Variation and Taxonomic Revision of Mink (Mustela vison) in Florida

Abstract: Mink are absent from most of the interior of peninsular Florida but occur in three disjunct, peripheral populations, where they are relatively common Examination of 171 Recent and three fossil specimens showed that each of these populations is a distinct subspecies The population from the gulf coast of northern Florida is described as a new subspecies, the status of the subspecies lutensis is confirmed, and evergladensis of southern Florida is subsumed as a disjunct population of the subspecies mink The new subspecies and lutensis appear to have differentiated from a common ancestor early in the Pleistocene The distribution of Recent populations can be explained by discontinuous coastal habitats and some other range-limiting mechanism, possibly either disease or predation by large, freshwater reptiles The carnassial teeth provide the most important dental characters distinguishing these southeastern mink, and variation is mainly in size A clinal north-to-south decrease in size of the dental apparatus is demonstrated within lutensis

Element Concentrations in Livers and Kidneys of Ranch Mink

Abstract: Reference ranges for element concentrations in livers and kidneys of "healthy" mink of known age, sex, and coat color and fed a conventional diet were determined. After euthanasia and removal of the pelts, liver and kidney samples were collected from 174 mink and analyzed for 22 elements using inductively coupled argon plasma emission spectroscopy. The diet of the mink was also analyzed for element concentrations. Descriptive statistics of element concentrations for livers and kidneys of the mink are given and compared with dietary element concentrations. Knowledge of normal tissue element concentrations for animals is essential for detection of abnormal con- centrations that may be indicative of disease problems. Tissue samples from animals presented for postmor- tem examination are frequently analyzed for element content to assist pathologists in diagnosing conditions involving mineral toxicoses or deficiencies. Normal tissue element concentrations are also useful to

Relationships between organochlorine concentrations in liver and muscle of otters.

Abstract: The European otter (Lutra lutra) is now threatened or endangered over much of its European range. The decline, which has taken place mainly during the past three decades, has been attributed to the toxic effects of organochlorine residues, with emphasis being placed on dieldrin or PCBs. Few otters were analyzed for organochlorines during the main period of decline but there is not considerable interest in the species. Experiments with ranch mink (Mustela vison) have shown that reproductive failure occurs when PCB concentrations in thigh muscle approach 50 mg kg{sup {minus}1} lipid. Because otters are closely related and have similar habits this value is becoming widely used to interpret the potential significance of PCB concentrations determined in otters. Furthermore, although the mink data refer to concentrations in muscle, interpretations of concentrations in otters have frequently been based on analyses of livers. Because of the diverse sources of material in Europe, only limited tissues may be made available for analysis, while costs may also prohibit the analysis of several tissues from a single carcass. The relationship between concentrations of organochlorines in muscle and liver tissues in otters has not been determined. This is the purpose of the present communication.

Influence of dietary fat source on growth and fur quality of mink and blue fox

Abstract: The influence of different dietary fat sources on growth and fur quality of the mink and the blue fox was studied. The fats used in the study were beef tallow, mink fat, capelin oil, soybean oil, rapeseed oil, and beef tallow: rapeseed oil mixture (50:50). The level of dietary fat was 20% in the dry matter of feed. All of the fat sources investigated here were of good quality guaranteeing approximately normal growth performance to the animals. No signs of fat peroxidation or vitamin E deficiency were found, and no adverse effects on feed consumption, feed palatability, growth of the animals and their fur characteristics were observed in the mink or in the blue fox.

Chromosomal and regional localization of the genes for UMPH2, APRT, PEPD, PEPS, PSP, and PGP in mink: comparison with man and mouse.

Abstract: Segregation of mink biochemical markers uridine 5’-monophosphate phosphohydrolase-2 (UMPH2), adenine phosphoribosyltransferase (APRT), phosphoserine phosphatase (PSP), phosphoglycolate phosphatase (PGP), peptidases D (PEPD) and S (PEPS), as well as mink chromosomes, was investigated in a set of mink × mouse hybrid clones. The results obtained allowed us to make the following mink gene assignments: UMPH2, chromosome 8; PEPD and APRT, chromosome 7; PEPS, chromosome 6; and PSP and PGP, chromosome 14. The latter two genes are the first known markers for mink chromosome 14. For regional mapping, UMPH2 was analyzed in mouse cell clones transformed by means of mink metaphase chromosomes (Gradov et al., 1985) and also in mink × mouse hybrid clones carrying fragments of mink chromosome 8 of different sizes. Based on the data obtained, the gene for UMPH2 was assigned to the region 8pter→p26 of mink chromosome 8. The present data is compared with that previously established for man and mouse with reference to the conservation of syntenic gene groups and G-band homoeologies of chromosomes in mammals.

Localization of the α2-macroglobulin gene and Lpm gene family on mink chromosome 9

Abstract: Using cloned cDNA for human α2-macroglobulin (A2M) as a probe, mink-Chinese hamster hybrid cells were analysed. The results allowed us to assign a gene for A2M to mink chromosome 9. Breeding tests demonstrated that the Lpm-locus coding for other related α-macroglobulin protein and the gene for peptidase B (PEPB) are linked 11±3 cm apart. The PEPB gene is located on mink chromosome 9, and hence, the Lpw-locus is on the same mink chromosome. The relationship of the genetic systems controlling the isotypically different α-macroglobulins in mink serum are discussed.

Mink (Mammalia; Carnivora; Mustelidae): correction of a widely quoted error

Abstract: Since the European Mink Mustela lutreola and the introduced American Mink M. vison are now sympatric in some parts of the former's native range, and since the two species are similar in appearance, ecology, and behaviour, a need has arisen for a simple way of discriminating live specimens of the two species in the field. Many publications, particularly field guides, have recommended diagnosis on the basis of the presence of white hair on the upper lip of the European species, and its absence in the American species. This is a mistaken suggestion, which should be avoided by authors. American Mink seldom if ever show the large white moustachial bands seen in some European Mink, and may indeed have no white hairs on the upper lip; but white patches of lesser size are common enough to be a possible cause of confusion.

Fine structure of the retinal epithelium and tapetum lucidum of the ranch mink Mustela vison.

Abstract: The morphology of the retinal pigment epithelium (RPE), Bruch’s membrane (complexus basalis), choriocapillaris and tapetum lucidum has been studied in the eye of the ranch mink ( Mustela vison

Influence of Fatty Acid Composition in Dried Raw Mink and Blue Fox Skins on Their Storage Aging and Dressing Properties

Abstract: The influence of fatty acid composition in dried raw mink and blue fox skins on their storage aging and dressing properties was assessed. The parameters studied were: changes in the fatty acid composition of the skins during one year's cold storage (+8°C, 70% RH), swelling, tannin fixation and such mechanical characteristics as tensile strength and tearing strength in fresh and one-year-old raw skins. The animals’ dietary backgrounds significantly influenced the changes in the fatty acid compositions of raw skins during storage. In addition, the duration of storage had a marked effect, with mink and blue fox skins differing significantly in this respect. Tannin fixation, skin thickness and percentage of elongation at break were considerably influenced by aging the furskins. Rancid dietary fat was found to cause collagen damage to mink skins. No other dietary effects were observed. Mink and blue fox skins differed from each other in all of the dressing characteristics measured. Blue fox skins seem...

Genetic polymorphism of IgG in the mink. V: Two new genetic markers of the lambda light chains of mink immunoglobulins, L4 and L5

Abstract: Two new allotypes of the light (L) chains IgG, L4 and L5, were identified in the mink with dispecific antiserum produced by immunization with allogenic IgG. By means of hybrid IgG molecules and proteolytic fragments, L4 and L5 were localized on the C region of the L chain. L4 and L5 occurred frequently in the three mink populations studied and L4 and L5 are inherited independently of the known mink C gamma allotypes. L4 and L5 are encoded by closely linked genes. The antigenic specificities of L4 and L5 were not identified in the closely related Mustelidae and in the other mammalian representatives. Consequently, L4 and L5 are species specific to mink. Determination of the phenotype combinations of the five allotypes on the L chains (including the new L4 and L5) demonstrated the existence of seven combinations only with a predominance of L1,2,3; L4,5, and L1,2,3,4,5 phenotypes. Based on the results obtained, it is concluded that the mink C lambda locus has a complex organization. A model for the mink C lambda locus with at least three or possibly five linked genes is suggested.

Diatom flora of Mink Creek, Idaho, USA

Abstract: —Diatoms were collected from an open-canopy and closed-canopy site on Mink Creek, Bannock County, Idaho, a third-order Rocky Mountain stream. Ninety diatom taxa were identified. Achnanthes ininutissvna Kuetz. and Navicula lanceolata (Ag. ) Kuetz. dominated the open-canopy site, whereas Cocconeis placentula var. eughjpta (Ehr.) CI. comprised greater than 40% of the diatom assemblage at the closed-canopy site. Seven oi the 10 most important diatoms were present at both sites. A high degree ofsimilarity was evident between natural and artificial substrates at both sites. Although most taxa were present at both sites, it is apparent from this study that differences in the abundance of taxa occur according to variations in light. The purpose of this paper is threefold: (1) to provide a description of the diatom assemblage present in an openand a closed-canopy section of a third-order Rocky Mountain stream, (2) to compare our findings with those of other studies on lotic diatom communities from mountain streams in Idaho, and (3) to compare the colonizing diatom assemblage on natural substrates with that on clay brick arti-

Quality and colour of melatonin—and bromocriptine-induced winter fur growth in mink ( Mustela vison ) given a supplemented diet

Abstract: An experiment was conducted to evaluate the effects of diet on fur colour and quality of bromocriptineand melatonin-induced winter pelage in mink. At weaning, 90 standard dark female kit mink were assigned randomly to one of two dietary regimens. Diet 1 (no. = 30) was a basal ranch mink diet, and diet 2 (no. = 60) was the basal diet, supplemented with liver and eggs. On 26 June 1986, mink given each diet were assigned to treatment (no. = 15) and control groups (no. = 15). Animals receiving diet 1 were treated with 120 mg melatonin implants (silastic) while those given diet 2 were treated with 120 mg melatonin implants, 60 mg bromocriptine pellets, or 60 mg bromocriptine pellets plus 18·6 mg melatonin implants (silastic). Control groups on each diet received no implants. Subsequently, fur growth was measured at biweekly intervals. Mink treated with 120 mg melatonin, 60 mg bromocriptine, and 60 mg bromocriptine plus 18·6 mg melatonin all moulted 1 month earlier than controls and exhibited significantly greater fur growth during the months of August and September (P < 0·05). Mink implanted with 120 mg melatonin, and bromocriptine plus melatonin were considered to be in fully prime pelage by mid October and were pelted by October 23. Mink receiving bromocriptine alone were not considered to be in prime pelage in October and were pelted in December with controls. Neither diet supplementation with liver and eggs, nor treatment to induce early fur growth had an effect on fur colour or quality. It was also concluded that treatment of mink with bromocriptine may not completely mimic the effect of exogenous melatonin on winter fur growth.