Swimming Activity of Farm Mink (Mustela vison) and its Relation to Stereotypies

Eighty farm mink were used to investigate whether access to swimming water and:or difference in cage size led to a difference in the level of stereotypies. Half of the animals grew up with free access to swimming water, and the other half without. In addition, two different cage sizes were used. Over 2 weeks the animals were scanned a total of 141 times. Animals in small cages had a higher level of stereotypies and were more active than those in large cages. No difference between animals with swimming water and animals with an empty basin was detected. The level of activity was lowest in animals in large cages, although not significantly so when water was present. The results presented here do not offer any support for the claim that farm mink with access to swimming water have a lower level of stereotypies than mink with access to an empty basin. Whether swimming is a behavioural need in farm mink is still debatable.     

Effects of Carbohydrate-free Diets on the Performance of Lactating Mink (Mustela vison) and the Growth Performance of Suckling Kits

The effects of carbohydrate-free diets on body weight changes, feed consumption, and plasma concentrations of nutrients, metabolites, and hormones in lactating mink and on growth performance in kits were investigated in a total of 108 litters during the lactation period of seven weeks. The litters were distributed in three experimental groups fed different ratios of metabolisable energy (ME) derived from protein and fat (61:38; 47:52; 33:66). The females and kits were weighed at parturition and 2, 3, 4, and 7 weeks after parturition. Blood samples were collected from females in the second, fourth, and sixth week of the lactation period. Carbohydrate-free diets fed to lactating mink can in principle support normal performance, health of the females, and growth performance of the kits. However, mink need a sufficient supply of available gluconeogenic precursors in the form of amino acids. In the present experiment, the diet with 33% of ME from protein contained insufficient amounts of gluconeogenic precursors for lactating mink, and three weeks post partum this group was excluded from the experiment. The differences in dietary protein level (61% and 47% of ME) and fat level (38% and 52% of ME) influenced the plasma concentrations of free fatty acids (FFA) and urea, but had minimal influence on plasma concentrations of other nutrients, metabolites, and hormones.     

Quantitative Glucose Metabolism in Lactating Mink ( Mustela vison ) - Effects of Dietary Levels of Protein,Fat and Carbohydrates

Glucose metabolism was measured during two consecutive years, 4 weeks postpartum, in a total of 36 yearling female mink, fitted with jugular vein catheters and raising litters of six to seven kits. The dams were fed ad libitum from parturition on diets with different ratios of metabolizable energy (ME) derived from protein:fat:carbohydrates (experiment 1: 61:37:2, 46:37:17, 31:37:32; experiment 2: 61:38:1, 47:52:1, 33:66:1). After 3 h fasting the dams were fed 210 kJ ME of the experimental diets. Two hours postprandially a single dose of 50 w Ci U- 14 C- and 2- 3 H-labelled glucose was administered to each dam and blood samples were drawn 5, 10, 20, 30, 45 and 60 min after the tracer administration. Glucose turnover rates were 4-5% min -1 in all dams, and the approximate daily glucose flux was 12-17 g day -1 ; however, these were not significantly affected by dietary treatment. In conclusion, the mink is able both to synthesize large amounts of glucose de novo and to utilize high levels of dietary digestible carbohydrates, and thereby to tolerate large variations in dietary carbohydrate supply.     

Glucose Homoeostasis and Regulation in Lactating Mink ( Mustela vison ): Effects of Dietary Protein,Fat and Carbohydrate Supply

The ability of lactating mink dams to control glucose homoeostasis, when fed diets containing different ratios of metabolizable energy (ME) from protein, fat and carbohydrates, was studied by measuring plasma concentrations of glucose, insulin, glucagon, urea and free fatty acids (FFA), in the fasted and absorptive state 4 weeks postpartum, in two consecutive years. A total of 36 yearling female mink, fitted with jugular vein catheters and raising litters of six or seven kits, was fed ad libitum lactation diets with different amounts of ME derived from protein, fat and carbohydrates (year 1:61:37:2, 46:37:17 and 31:37:32; year 2:61:38:1, 47:52:1 and 33:66:1). After 3 h fasting the dams were fed 210 kJ ME of the experimental diets. Blood samples were drawn 10 and 5 min before feeding and 30, 60, 90, 120, 150 and 180 min postprandially. The glucose concentration was increased 30 to 150 min postprandially in dams fed the carbohydrate-containing diets (46:37:17 and 31:37:32), whereas the glucose concentration showed no postprandial response in dams fed the carbohydrate-free diets (61:38:1, 47:52:1 and 33:66:1). Plasma insulin concentrations were increased 30 to 120 min postprandially in all dams, irrespective of dietary treatment. Plasma concentrations of glucagon were higher ( P <0.005) in dams fed the low-protein diets (31:37:32 and 33:66:1) than in dams fed the high-protein diets (61:37:2 and 61:38:1). Postprandially, the glucagon : insulin ratios decreased in dams fed the carbohydrate-containing diets, whereas the glucagon:insulin ratios tended to increase in dams fed the carbohydrate-free diets. Plasma concentrations of urea were significantly higher in dams fed the high-protein diets. Plasma concentrations of FFA, measured in the second experiment (year 2) only, showed increased concentrations postprandially, the responses being significant in dams fed the 33:66:1 and 61:38:1 diets. In conclusion, the mink is able to regulate the concentrations of blood constituents involved in maintaining glucose homoeostasis, and thereby to adapt to a wide range of dietary protein and carbohydrate supply.     

Effects of High Dietary Levels of Fresh or Oxidised Fish Oil on Performance and Blood Parameters in Female Mink (Mustela vison) During the Winter,Reproduction, Lactation and Early Growth Periods

The effects of high dietary levels of fresh or moderately oxidised fish oil on performance and blood parameters in mink females were investigated during the winter, reproduction, and lactation periods. Furthermore, the effects of the diets on kit performance were investigated during the lactation and early growth periods. The investigation was carried out with a total of 292 females distributed in five experimental groups fed fresh fish oil stored frozen, fresh fish oil ensiled, oxidised fish oil stored frozen, oxidised fish oil ensiled, and soya oil, respectively. The females were weighed three times during the winter period, and the females and the kits were weighed at parturition and 2, 4, and 7 weeks post partum. Blood samples were collected from the females and the kits 6 and 8 weeks post partum, respectively. The results show that high dietary levels of fresh or moderately oxidised fish oil could be used for mink females during the winter and reproduction periods without any negative effects on performance, health and reproduction results. However, high levels of fish oil resulted in lower kit weights at weaning. These negative effects on kit growth were related to the dietary composition fed during the lactation and early growth periods and not to the diet used during the preceding winter and pregnancy periods. A high intake of polyunsaturated fatty acids resulted in a decreased number of blood platelets for both mink females and their kits.     

Influenza A Virus Surveillance in the Invasive American Mink (Neovison vison) from Freshwater Ecosystems,Northern Spain

Influenza A viruses (IAVs) are negative‐sense, single‐stranded and segmented RNA viruses of the Orthomyxoviridae family that may cause acute respiratory disease in a wide range of birds and mammals. Susceptibility of several species within the family Mustelidae to IAVs has been reported as a result of natural or experimental infections. The objectives of this study were to assess whether free‐ranging American mink populations from Northern Spain were infected with IAV and try to define the role of this species in the epidemiology of IAV. Sera from 689 American mink from Northern Spain captured between 2011 and 2014 were tested for the presence of antibodies against IAVs using a commercial competition cELISA. Positive sera were further analysed with haemagglutination inhibition (HI) assay. Fifteen of the 689 (2.2%, 1.3–3.6 CI_95%) of the American minks analysed were ELISA positive. No significant differences were observed between years of capture, provinces, river basins, sexes or ages of the animals. All seropositive sera resulted negative to the panel strains used in the HI assay, showing that the most relevant strains circulating in swine, the most relevant avian subtypes (H5 and H7) and the H10N4 subtype isolated in minks have not been circulating in this free‐ranging exotic carnivore from Spain. In the light of these results, the free‐range American mink from Northern Spain do not seem to have an important role in the epidemiology of IAVs.     

Molecular and morphometric study of metacercariae and adults of Pseudamphistomum truncatum (Opisthorchiidae) from roach (Rutilus rutilus) and wild American mink (Mustela vison)

The presence of metacercariae and adults of the trematode Pseudamphistomum truncatum in roach and mink, respectively, was recorded in Lake Fure North of Copenhagen, Denmark. This zoonotic digenean opisthorchiid represents a threat to humans due to its ability to infect the biliary system following ingestion of inadequately processed infected fish. Therefore precise species identification of infective metacercariae in fish used for human consumption is essential. Due to the relatively limited information on metacercarial identity obtained by morphometric studies a series of molecular techniques were used to link the larval parasite in fish with the un-equivocally diagnosed adults in the biliary system of the mink. By the use of carefully selected polymerase chain reaction (PCR) primers and subsequent sequencing of the ITS region from both metacercariae and adults full sequence identity of both metacercariae and adults were confirmed. The presence of this parasitosis in fish from a lake used for both commercial and recreational fisheries call for hygienic alerts in order to prevent accidental human infection with this opisthorchiid.     

饲粮脂肪水平对雌性水貂营养物质消化率、氮代谢及繁殖性能的影响

本试验旨在研究不同脂肪水平饲粮对雌性水貂营养物质消化率、氮代谢及繁殖性能的影响。选择健康、体重相近的初产水貂120只,随机分成4组,每组3个重复,每个重复10只水貂。4组水貂分别饲喂蛋白质水平为45%,脂肪水平分别为10%(F10组)、14%(F14组)、18%(F18组)和22%(F22组)的试验饲粮。试验期为配种至产仔。结果表明:饲粮脂肪水平对水貂干物质和蛋白质消化率的影响不显著(P0.05),随着饲粮脂肪水平的升高,脂肪消化率呈上升趋势,其中F18、F22组显著高于F10组(P0.05)。饲粮脂肪水平对水貂日采食量和日食入氮量有极显著影响(P0.01),随着饲粮脂肪水平的升高,日采食量和日食入氮量均呈下降趋势。饲粮脂肪水平显著影响日粪氮和尿氮排出量及日氮沉积量、氮生物学效价(P0.05)。其中,F18组日粪氮和尿氮排出量最低,氮生物学效价最高。F14和F18组配种率、产仔率、窝产活仔数差异不显著(P0.05),但显著优于其他组(P0.05)。综合各项指标得出,在本试验条件下,水貂妊娠期饲粮蛋白质水平为45%时,饲粮的适宜脂肪水平为14%~18%,并且适宜饲粮脂肪水平能够提高水貂对蛋白质的利用率。     

饲粮铜、锌含量及其互作效应对育成期水貂生长性能、营养物质表观消化率及铜、锌和氮代谢的影响

本试验旨在研究饲粮铜、锌含量及其互作效应对育成期水貂生长性能、营养物质表观消化率及铜、锌和氮代谢的影响。试验采用3×3完全随机试验设计,分别在基础饲粮(不添加铜、锌)基础上添加3个水平(0、15和30 mg/kg)的铜(以硫酸铜形式)和3个水平(0、150和300 mg/kg)的锌(以硫酸锌形式)。选用(60±3)日龄、体重相近的健康雄性水貂108只,随机分成9组,每组12个重复,每个重复1只。预试期为7 d,正试期为60 d。结果表明:1)饲粮铜含量对水貂平均日增重(P=0.069)和料重比(P=0.058)有影响趋势。以平均日增重为响应指标,通过二次响应面回归模型估测育成期水貂铜、锌适宜含量分别为51和117 mg/kg时,此时水貂可以获得最大平均日增重14.10 g。2)饲粮铜含量对水貂粗脂肪的表观消化率有显著影响(P=0.019),对铜的表观消化率有极显著影响(P=0.001);饲粮锌含量对水貂粗脂肪和铜的表观消化率均没有显著影响(P0.05);饲粮铜、锌含量的互作效应对水貂粗脂肪的表观消化率没有显著影响(P0.05),对铜的表观消化率有极显著影响(P=0.002)。3)饲粮铜含量对水貂铜的摄入量、粪铜和尿铜的排出量以及铜沉积量均有极显著影响(P=0.001);饲粮铜、锌含量的互作效应对铜沉积量有显著影响(P=0.019),对粪铜的排出量有极显著影响(P=0.001)。饲粮锌含量对水貂锌的摄入量、粪锌和尿锌的排出量以及锌沉积量均有极显著影响(P=0.001);饲粮铜、锌含量的互作效应对锌代谢指标没有显著影响(P0.05)。饲粮铜、锌含量以及二者的互作效应对水貂氮代谢指标没有显著影响(P0.05)。综合试验结果得出,饲粮中铜、锌含量分别为51、117 mg/kg时,育成期水貂可以获得最大平均日增重;饲粮中铜含量为39.83 mg/kg时,育成期水貂对粗脂肪的表观消化率较高,对锌的表观消化率和锌的代谢没有产生显著影响;饲粮锌铜比例大于40时,会降低育成期水貂铜的表观消化率和铜沉积量。     

Use of Water for Swimming and its Relationship to Temperature and Other Factors in Farm Mink (Mustela vison)

An investigation into swimming behaviour and its relationship to outdoor temperature was conducted in 40 ranch mink. Two different cage sizes were used and all animals had access to a basin filled with water 15 cm deep. During the years 1994-1998, water loss from the basin and temperatures at a nearby weather station were recorded once a week. In the last year 11 mink were video-recorded for 24 h. Using the monthly average daily water loss as an indicator, swimming activity showed a clear annual variation over 4 years and was positively correlated with average monthly temperature. With regard to swimming activity, a large individual variation existed: average water loss varied from 10 ml to nearly 4 litres per day, with those in large cage units having the greatest water loss. The video-recordings confirmed this variation: the number of swims ranged from zero to 177 during 24 h and there was an indication of more swimming bouts in the mink in the large cage units. The duration of swims varied from 2 to 55 s per bout. The relationship between swimming and general activity is discussed, along with the importance of water for swimming as a means of thermoregulation.     

矿物质营养对母畜繁殖性能的影响

本文就矿物质营养对母畜繁殖的作用以及缺乏所发生的症状分别作了系统的阐述。     

Comparative Nutrient Digestibility in Blue Foxes (Alopex lagopus) and Mink (Mustela vison) Fed Diets with Diverging Fat: Carbohydrate Ratios

Abstract

Nutrient digestibilities were evaluated in comparative experiments with blue foxes and mink by using six diets differing in fat:carbohydrate (F:C) ratios. In mink, apparent digestibilities of N and amino acids decreased with decreasing F:C ratio. N digestibility, and most amino acid digestibilities, were higher in blue foxes than in mink (P < 0.01). Fat digestibility in mink, but not in blue foxes, declined as the F:C ratio decreased (P < 0.05). Fat digestibility was higher in blue foxes than in mink (P < 0.05). Carbohydrate digestibility was not affected by the F:C ratio, but high levels of carbohydrates were digested more completely by foxes than by mink. The use of mink digestibility values in feed evaluations for blue foxes will consequently underestimate digestibility. Thus, to evaluate feed correctly, separate digestibility determinations should be made for mink and foxes.     

水貂阿留申病的历史回顾及最新研究概述

水貂阿留申病是阻碍养貂业发展的世界性攻关病害。自人们发现该病至今已有５０余年的历史,尽管国内外有关专家学者,从没间断过对该病的研究,但始终没能攻克该病的免疫防制问题;值得庆幸的是,在国家科委和农业部畜牧兽医司等部门的大力资助下,我们对阿留申病的免疫原性和免疫机制进行了较系统深入的研究,并研制出了阿留申病灭活疫苗,现已在多个大型貂场进行小试。该文对阿留申病的病史和危害,以及最新研究进展和重大技术突破进行了较全面系统的论述。     

Vitamin B12 Supplementation to Mink (Mustela vison) in the Prevention of Feed-Induced Iron Deficiency Anaemia: I. Effect on Growth Performance and Fur Quality Characteristics

Abstract

Vitamin B₁₂ supplementation in the prevention of feed-induced iron deficiency anaemia was evaluated with six treatment groups of mink kits, comprising a control group and five groups fed an anaemiogenic diet either unsupplemented, supplemented with vitamin B₁₂ orally, or by intramuscular injection, with iron therapy by ferrous fumarate and cysteine, and iron therapy plus vitamin B₁₂ orally. Unsupplemented animals showed symptoms of anaemia including poor growth performance, achromotrichia and poor fur quality. Oral vitamin B₁₂ supplementation, but not injections, had some effect in preventing anaemia, indicating an influence on intestinal iron absorption. Iron therapy completely prevented the occurrence of anaemia, and simultaneous addition of vitamin B₁₂ had no further positive effect.     

饲粮粗蛋白质与外源褪黑激素水平对水貂生长性能、血清生化指标及营养物质消化率的影响

本试验旨在研究饲粮粗蛋白质(CP)和外源褪黑激素(MT)水平对水貂生长性能、血清生化指标及营养物质消化率的影响。选取90只50日龄体重一致的健康雄性水貂,随机分为6组,每组15个重复,每个重复1只水貂。采用3×2两因子试验设计,即3个饲粮CP水平(32%、36%和40%)和2个皮下埋植的外源MT水平(0、10 mg/只)。试验期64 d。结果表明:1)40%CP水平时,10 mg/只MT组水貂末重显著高于0 mg/只MT组(P<0.05);32%CP水平时,10 mg/只MT组水貂平均日增重显著高于0 mg/只MT组(P<0.05);饲粮CP和外源MT水平对水貂末重、平均日增重无显著互作效应(P>0.05)。2)32%和40%CP水平时,皮下埋植10mg/只MT可极显著降低水貂血清白蛋白(ALB)含量(P<0.01);32%CP水平的血清甘油三酯(TG)含量均显著高于40%CP水平(P<0.05);饲粮CP和外源MT水平对水貂血清ALB含量存在极显著互作效应(P<0.01),对血清总蛋白(TP)、尿素氮(UN)、TG含量和碱性磷酸酶(ALP)活性无显著互作效应(P>0.05)。3)10 mg/只MT组中,32%和36%CP水平的水貂干物质采食量极显著高于40%CP水平(P<0.01);0 mg/只MT组水貂中,32%CP水平的干物质采食量和干物质排出量极显著高于40%CP水平(P<0.01);饲粮CP和外源MT水平对水貂采食量、干物质采食量、干物质排出量和干物质消化率均无显著互作效应(P>0.05)。4)10 mg/只MT组中,36%CP水平的水貂粗脂肪消化率显著高于32%和40%CP水平(P<0.05),32%CP水平的水貂钙消化率极显著高于40%CP水平(P<0.01),32%CP水平的水貂磷消化率极显著高于36%和40%CP水平(P<0.01);0 mg/只MT组中,36%CP水平钙消化率极显著高于40%CP水平(P<0.01),32%CP水平的水貂磷消化率极显著高于36%和40%CP水平(P<0.01);饲粮CP和外源MT水平对水貂CP、粗脂肪、钙和磷的消化率无显著互作效应(P>0.05)。综合本试验各项测定指标可以得出,皮下埋植10 mg/只外源MT时,水貂较适宜的饲粮CP水平为32%～36%。     

Factors influencing farmers' responses to welfare legislation: A case study of gestation sow housing in Flanders (Belgium)

In the light of the EU ban on individual confinement of gestating sows which will have to be fully implemented by 2013, a survey was conducted among a representative sample of Flemish pig producers. The questionnaire was sent by post to 250 farmers in 2003 and 352 farmers in 2005 of which 219 and 296, respectively, provided valid responses via telephone. The percentage of respondents housing (some of) their sows in group was 10.5% in 2003 and 16.2% in 2005. These farmers were more likely to have a successor than farmers housing their sows individually. The most common group housing systems were free access stalls (24%) followed by electronic feeding stations (21%), ad libitum feeding (20%), feeding stalls/troughs (18%), and drop/trickle feeding systems (13%). Interval (4%) and electronic feed dispensers (0%) were very rare in Flanders. The main criteria for having chosen a particular group housing system related to sow health and welfare, investment costs and amount of labour. The relative importance of economic reasons has increased over time. Users were generally rather satisfied with their group housing system. Farmers using group housing for all their sows were more satisfied than farmers using both group and individual housing. Users of ad libitum feeding systems (and feeding stalls/troughs) were more satisfied than users of electronic feeding stations. A minority of respondents was planning to change to group housing within two years time (4.1% in 2003 and 7.4% in 2005). These tended to be young farmers with a large sow herd and 58% reported to opt for free access stalls. The main reason why the remaining respondents were not planning to change to group housing yet is that they will stop farming activities before 2013. This reason was particularly important for older small-scale farmers without a successor. In contrast, the lack of financial resources and security was particularly important for young farmers of a large sow herd with a likely successor. An increasing group of farmers (often without a successor) reported to delay changing to group housing because they consider individual housing more profitable. These results show that, in Flanders, the conversion to group housing is taking place slowly, that the reasons for not converting yet vary according to the farmers' age, the likelihood of a successor and herd size, and that there are differences between operational group housing systems concerning herd size, age of the system, sow management and user satisfaction.     

Effects of dietary protein levels on digestibility of nutrients and growth rate in young female mink (Mustela vison)

This study investigated digestibilities of nutrients and feed efficiency in female mink at the different dietary protein levels during the mink growth period. Effects of dietary protein on growth performance of minks were also measured. Sixty 45‐day‐old healthy female minks were randomly assigned to 6 treatment groups with 10 animals in each group. Animals were fed diets varying in protein levels: 28% (Group I), 30% (Group II), 32% (Group III), 34% (Group IV), 36% (Group V) and 38% (Group VI), respectively. The digestibilities of key nutrients were determined on Day 14 after initiating the experiment and the last 3 days. From the beginning of the study, body weight and feed intake were weighed and recorded every other week in order to calculate the average daily bodyweight gain and the feed efficiency. The trial had demonstrated that nitrogen intake was greatly significantly different, which was affected by dietary protein levels (p < 0.001). Growth performance of minks was impaired when dietary protein level was at 28%. When dietary protein level was at 34%, minks had the best daily gains, feed efficiency, and digestibilities of some key nutrients.     

Serology and protein electrophoresis for evidence of exposure to 12 mink pathogens in free-ranging American mink (Neovison vison) in Argentina

Background: Basic pathologic characteristics for farmed minks were previously reported worldwide. However, its status in the wild has not been studied in detail.

Objective: Serology and electrophoresis were carried out for evidence of exposure to 12 mink pathogens on two different locations.

Animals and methods: Serology was done in 87 wild minks by reference techniques against Toxoplasma gondii, Encephalitozoon cuniculi, Neospora caninum, Brucella abortus, Mycobacterium bovis, Leptospira interrogans, canine distemper virus (CDV), canine adenovirus (CAV), canine parvovirus (CPV), rabies virus (RV), Influenza A virus (FLUAV) and Aleutian disease virus (ADV). Hypergammaglobulinemia, the ADV main clinical feature, was determined by conventional electrophoresis.

Results: Seventy-one percent of the 87 sera had antibodies against one or more pathogens. ADV accounted for the highest seroprevalence (29%), followed by T. gondii (26%), L. interrogans (14%), M. bovis (12%), B. abortus (9%), N. caninum (3%), CPV (3%) and CDV (2%). Seroprevalence was influenced by location but not sex or age. Additionally, 16% of the seropositive samples for ADV had gammaglobulin levels >40.0 g/L. Antibody titers for CDV and CPV were low and difficult to interpret as almost all these cases had borderline concentrations.

Conclusion: A cautious interpretation of the results is urged as the epidemiological role of the wild mink is largely unexplored for most of these agents. Nevertheless, the information may be clinically relevant..     

Fatty Fish and Defatted Fish Products for Male Mink (Mustela vison) in the Growing-Furring Period: II. Effects on Haematological and Clinical-Chemical Parameters,Vitamin E Status and Fatty Acid Composition

The effects of different dietary levels of marine lipids in the diets with a constant distribution of metabolizable energy (ME) on protein, fat and carbohydrate were investigated in male mink kits in the growing-furring period during 2 consecutive years. The physiological investigations included 15 males per experimental group, each consisting of about 75 males. Fat herring and mackerel scrap were used in amounts resulting in levels of marine lipids of 30, 50 and 70% of total dietary lipid, respectively. Defatted herring scrap was used in proportions of 12, 23 and 32% in the diets. Haematocrit value, haemoglobin concentration, number of erythrocytes, leucocytes and platelets, plasma activities of alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT) and creatine kinase (CK), concentrations of tocopherols in plasma, liver and adipose tissue, composition of fatty acids (FA) in liver and adipose tissue, body weight, weight of liver and heart in relation to body weight, and liver fat content were studied. The number of platelets decreased with an increasing proportion of marine lipids of total content of dietary lipids. A high intake of fatty fish products had no influence on the health status of the animals evaluated by haematological and clinical-chemical analyses, vitamin E status and FA composition in growing-furring male mink. No negative effects on the health of the animals were demonstrated when feeding with defatted herring scrap.     

Effects of dietary copper on elemental balance,plasma minerals and serum biochemical parameters of growing-furring male mink(Mustela vison)

The objectives of this study were to study the effects of different levels of dietary copper on copper and zinc balance, plasma minerals and serum biochemical parameters of mink in the growing-furring periods. One hundred and five standard dark male mink were randomly assigned to seven groups with the following dietary treatments: basal diet with no supplemental Cu(Control); basal diet supplemented with either 6,12, 24, 48, 96, or 192 mg/kg Cu from copper sulfate,respectively. The average daily gain(ADG) linearly(P = 0.0026, P = 0.0006) responded to increasing levels of Cu; maximal growth was seen in the Cu24 group. Feed efficiency tended to improve with the increase of dietary copper level(linear P = 0.0010, quad, P = 0.0011). Fecal copper, urinary copper, retention copper responded in a linear(P 0.05) fashion with increasing level of Cu. The effect of level of Cu was linear(P 0.001) for plasma Cu concentration. The serum glutamic-oxalacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) activities were increased linearly(P 0.05) with dose of Cu, but serum total protein(TP) and albumin(ALB) concentrations decreased linearly(P 0.05) as dietary copper levels increased. Effect of level of Cu was linear(P 0.001) for serum ceruloplasmin(CER) concentration or Cu-Zn superoxide dismutase(Cu-Zn SOD) activity. Supplemental dose of Cu linearly decreased serum triglyceride(TG)(P = 0.011) and total cholesterol(TC)(P = 0.007). Our results indicated that the activity of Cu-dependent enzymes was enhanced by increasing dietary Cu concentration and that supplementation of Cu in the diet of mink could alter the plasma lipid profile and copper concentration.