Mink Feed Research Articles

Urinary and plasma metabolome of farm mink (Neovison vison) after an intervention with raw or cooked poultry offal: a 1H NMR investigation

ABSTRACT The introduction of high amounts of cooked poultry offal in mink feed has been associated with health problems in growing mink. Cooking mink feed is a convenient way of reducing microbiological activity, but it may have a negative effect on raw material quality and animal welfare. This study investigates growth and health of mink fed raw or cooked poultry offal and describes urinary and blood plasma metabolic changes related to the feeding. A total of 65 male mink were divided in three feeding groups, two fed cooked offal and one group fed raw offal, and the plasma and urine samples were collected at 3 time points during the growth. Both bio-fluids and feed samples were measured by 1H NMR spectroscopy and resulted metabolomics data were analysed using univariate and multivariate statistical methods that revealed dominating effect of the mink growth stages and to a less extent the feeding regime. Metabolome differences in relation to low body mass index (BMI) and kidney lesions were observed in plasma. Disease and decrease in BMI was associated with high creatinine and dimethylglycine content in plasma. These molecules were also particularly indicative of the cooked feeds. Moreover, low urinary taurine levels were also associated with disease and low BMI. Individual mink appeared to show negative effects of the cooked feed diet, including impaired growth and gross pathological lesions involving the kidneys. This may be related to the absorption of essential metabolites such as amino acids and fats, necessary for mink growth, that are negatively impacted by the cooking process.

Spread of LA-MRSA CC398 in Danish mink (Neovison vison) and mink farm workers

More than 55 million mink skins were produced globally in 2017. As a consequence, a large number of people are employed in mink production worldwide. In Denmark, farmed mink were found to constitute a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC) 398 and 6000 mink farm workers in Denmark are potentially exposed to LA-MRSA CC398. The study aim was to elucidate the source of LA-MRSA CC398 in mink farms and to investigate possible transmission to humans. In total, 161 LA-MRSA CC398 isolates from mink (n = 65), mink feed (n = 16) and humans (n = 80) with reported contact to mink, were whole-genome sequenced and compared to 183 LA-MRSA CC398 isolates from Danish pigs and an international collection of 89 S. aureus CC398 isolates. Most of the mink-associated isolates clustered within the predominant LA-MRSA CC398 lineages circulating in the Danish pig production, supporting that pigs are a source of LA-MRSA CC398 in mink feed, mink, and mink farmers.

Characterization of cod (Gadus morhua) frame composition and its valorization by enzymatic hydrolysis

This study aimed at evaluating proximate composition, phosphorous content, amino acid (AA) and fatty acid (FA) profiles of cod (Gadus morhua) frame at five different sampling times (March 2017 to March 2018). Furthermore, the valorization possibility of cod frame by application of enzymatic hydrolysis was investigated using the samples from September 2017. In terms of protein content, this sample showed a significantly (P < 0.05) higher level (16.5 %) compared to the other samples, whereas lipid and phosphorous contents varied in a narrow range of 0.9–1.1 % and 2.9–4.4 %, respectively, (P < 0.05). Furthermore, the total amino acids (AAs) content varied from about 98–155 mg/g in minced cod frame. Enzymatic hydrolysis of minced cod frame (MCF) and heated cod meat (HCM) was carried out by application of Alcalase and Neutrase, either individually or sequentially to obtain fish protein hydrolysate (FPH) and bone powder rich in phosphorus and calcium. The protein content of FPH varied from 76 % to 84 % and soluble-nitrogen in trichloroacetic acid (SN-TCA) index varied from 30.6 to 40.3%, resulting in similar trends for yield and nitrogen recovery. Considerable amounts of phosphorus and calcium (330 and 583 g/kg, respectively) were recovered from the cod frame bones after enzymatic hydrolysis. This study showed that it is possible to produce bone powder rich in phosphorous and calcium as well as peptides from the cod frame. Thus, the cod frame side-stream can be converted from its current use as mink feed ingredient into higher value products for human consumption, without generating new waste products.

An alien fisher in Patagonian South America

While doing fieldwork in the Cape Horn Biosphere Reserve at the southernmost tip of South America (Patagonia), we saw an American mink (Neovison vison) diving into a kelp forest and later emerging with an enormous golden kingklip (Genypterus blacodes), which it ate on the rocky shore. Mink were introduced to Chile and Argentina by fur farmers in the 1940s. Since then, this invasive, semiaquatic mammal has spread through Patagonia, feeding on mammals, birds, and fishes. Of the fishes, mink prey on small exotic salmonids, galaxiids, and notothenioids. Astonishingly, this mink had caught a demersal fish that was larger than itself. The kingklip, a marine predator that is important for small-scale fisheries, inhabits depths from the intertidal zone to 1000 m, but is most abundant between 50 m and 500 m. So, this was likely an unusual prey for a mink, raising new questions about mink's feeding habits. Are we detecting all native species that are affected by invasive mink? Despite using scat or stable isotope analyses to identify the prey items of invasive species, direct observations can also contribute essential data. The kingklip has very small, smooth-edged scales, which can make it undetectable in scat. How did the mink catch a marine demersal fish? The boulder-covered seafloor is a perfect habitat for a kingklip, but mink must dive to catch this prey. Most diving mink studies are done in freshwater environments where dives typically do not exceed 3 m depth. Our observation also provides questions about invasive mink ecology: has their diving behavior been learned in marine environments, and are mink expanding beyond their normal range in this novel environment? What are the likely consequences for the marine food web in Patagonia?

Microbiological quality of mink feed raw materials and feed production area

BackgroundThe quality of mink feed and raw ingredients affect health and growth. The objectives of this study were to examine the microbiological quality of ready-to-eat mink feed and its raw ingredients, screen the plant part of the feed for mycotoxins, and determine the hygiene of the production environment in the feed processing facilities. The results of the study are important for identification of critical steps in the feed production and for formulation of recommendations for improvements of production processes to obtain better quality feed. Feed and swab samples were taken at three Danish mink feed producers October 2016 and May 2017, respectively. Viable counts, detection of methicillin-resistant Staphylococcus aureus (MRSA), influenza virus and filamentous fungi were performed together with qualitative chemical analyses for bioactive fungal metabolites and mycotoxins. Swab samples were analyzed for total viable counts.ResultsViable counts varied between 7.2 × 102 and 9.3 × 107 cfu/g in raw ingredients and between 107 and 109 cfu/cm2 on different surfaces at the feed production facilities. A pork meat product, pork haemoglobin, pork liver and a poultry mix was found positive for MRSA, while monophasic Salmonella [4,5,12:i:-] was detected in a pork meat product. Neither MRSA nor Salmonella was detected in any ready-to-eat feed. Influenza A virus was not detected in any sample. Filamentous fungi were detected in all analysed samples of ready-to-eat feed while dihydro-demethyl-sterigmatocystin was found in almost 50% of all ready-to-eat feed samples and in 80% of the sugar beet pulp. Fumonisins and other Fusarium toxins were found especially in corn gluten meal and extruded barley and wheat.ConclusionsMink feed contained a cocktail of mycotoxins and bacteria, which may not per se cause clinical disease, but may affect organ function and animal performance and well-being.

Organochlorine contaminants in wild mink from the lower Great Lakes basin, Canada, 1998-2006.

Organochlorine contaminants were measured in livers of wild mink (Neovison vison) trapped in the lower Great Lakes basin from 1998 to 2006. To assess exposure and potential risk in mink feeding on Great Lakes biota, concentrations of contaminants were compared in mink trapped within 7.8km of the shoreline as well as at inland sites (i.e., 8-40km). Overall, significant spatial variation in mean hepatic concentrations of sum PCBs and seven other organochlorines was found in mink from 13 Great Lakes sites, many of which are within the Great Lakes Areas of Concern. Mean sum PCB concentrations, on a lipid weight basis, ranged from 2μg/g in mink from inland Lake Ontario sites to 44μg/g in mink from western Lake Erie. Concentrations of other organochlorines in mink were generally low. Mink from western Lake Erie had the highest mean cumulative organochlorine burdens dominated largely by PCBs. A significant age effect was found with 1-year-old mink having significantly higher PCB burdens than mink less than 1year in age. With respect to published PCB threshold effect concentrations, some mink exceeded those associated with effects on reproduction and survival as well as the presence of jaw lesions. This was most consistently found in western Lake Erie where the health of populations of wild mink may be adversely affected and where no mink 2years of age or older were collected.

Livestock-associated methicillin-resistant Staphylococcus aureus is widespread in farmed mink (Neovison vison)

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) clonal complex (CC) 398 is widespread in the Danish pig production with around 90% of herds being positive. Since 2009, cases of CC398 LA-MRSA infections in Danish mink farmers have been observed. The objective of the study was to examine the presence of LA-MRSA in farmed mink.The investigation comprised three different sample types 1) clinical samples from carcasses submitted to the laboratory for diagnostic examination, 2) paws and pharyngeal swabs from healthy animals collected at pelting, and 3) feed samples from mink feed producers.In clinical samples, LA-MRSA was found in 34% of submissions and was most prevalent in samples from paws (33%) and pharynx (17%), followed by nasal and intestinal samples (each 13%), whereas it was never detected in perineal samples. LA-MRSA was found in healthy animals on 40% of the investigated farms, including paw samples (29%) and pharyngeal samples (16%). Twenty out of the 108 feed samples from feed producers were positive for LA-MRSA. The dominant spa-types were t034 and t011 associated to CC398, corresponding to the dominant spa-types detected in the Danish pig production, from which slaughter offal is used for mink feed. The spa-types, the high prevalence of LA-MRSA on paws and in pharynx, and its detection in feed samples, suggest feed as a possible source of LA-MRSA in mink.

Abortion and mortality in farm mink (Neovison vison) associated with feed-born Clostridium limosum

Disease in mink clinically characterized by abortion and increased mortality among pregnant female mink on 28 Danish farms was observed during April and May 2015. Most of these farms suffered extensive disease problems, including a significant increase in the number of mated females without litters. Pathological, microbiological and molecular biological methods were applied to investigate the cause of disease. Necropsies of animals found dead revealed fragile and partially dissolved (liquefying) uterine tissue, with the presence of Gram positive rod-shaped bacteria. These slow growing bacteria were isolated by anaerobic culturing and identified as Clostridium limosum by both MALDI-TOF mass spectrometry analysis and 16S rRNA gene sequencing. All the performed tests for relevant differential diagnoses were negative. Foodborne disease was indicated because all the affected farms were served by the same feed factory. A specific PCR-based analysis was developed for positive identification of C. limosum and used to screen archived feed samples from the implicated feed factory. Both C. limosum 16S rRNA genes and C. limosum collagenase genes were identified in both mixed feed and more specifically in raw chicken carcass used as one of the components in the mixed feed, which was therefore identified as the most likely source of contamination. Based on the results of this investigation it is concluded that C. limosum can be associated with abortion and increased mortality in pregnant mink females and it is consequently recommended that raw materials contaminated with C. limosum should be avoided in mink feed, in particular during the whelping season.

Robotic Design Choice Overview Using Co-Simulation and Design Space Exploration

Rapid robotic system development has created a demand for multi-disciplinary methods and tools to explore and compare design alternatives. In this paper, we present a collaborative modeling technique that combines discrete-event models of controller software with continuous-time models of physical robot components. The proposed co-modeling method utilizes the Vienna development method (VDM) and MATLAB for discrete-event modeling and 20-sim for continuous-time modeling. The model-based development of a mobile robot mink feeding system is used to illustrate the collaborative modeling method. Simulations are used to evaluate the robot model output response in relation to operational demands. An example of a load-carrying challenge in relation to the feeding robot is presented, and a design space is defined with candidate solutions in both the mechanical and software domains. Simulation results are analyzed using design space exploration (DSE), which evaluates candidate solutions in relation to preselected optimization criteria. The result of the analysis provides developers with an overview of the impacts of each candidate solution in the chosen design space. Based on this overview of solution impacts, the developers can select viable candidates for deployment and testing with the actual robot.

Optimisation of protocol for Clostridium botulinum detection in mink feed

Abstract As the test material mink feed with natural microflora was used. The analyses were conducted using Wrzosek and TPGY broth media, and Willis–Hobbs and Zeissler differential agar media. Wrzosek, Willis–Hobbs, and Zeissler media are described in Polish Standards approved by the National Standards Body in Poland and routinely used in detection of anaerobic bacteria in Poland. Detection and identification of C. botulinum was performed with a previously validated real-time PCR method based on ntnh gene detection, which is common in all C. botulinum toxotypes. The use of Wrzosek broth and Zeissler agar in routine analyses for detection and identification of C. botulinum was ineffective and limited. The obtained results showed the highest culturing process effectiveness in TPGY broth with 72 h incubation at 30°C and isolation on Willis–Hobbs agar. The real-time PCR method based on ntnh gene detection used in this study could be utilised as a supplementary tool to the mouse lethality assay.

Food niche variation of European and American mink during the American mink invasion in north-eastern Belarus

Understanding processes allowing the co-existence of ecologically similar species is important but difficult to study in community ecology. Introductions of alien species are unplanned experiments allowing investigation of co-adaptation of both native and invasive species over a short period. We analysed food niche differentiation between native European mink and alien American mink after invasion of the latter species in Belarus. European mink feed mainly on crayfish, frogs and fish whereas American mink prefer small mammals, fish and frogs. The diet of both species varied between seasons and during the period of alien mink invasion. Concurrent with the progress of American mink invasion, the European mink food niche has narrowed to feeding mainly on frogs, with the proportion of aquatic prey (fish and crayfish) in their diet drastically reduced. In contrast, the American mink food niche became wider during invasion. The breadth was stable but included a varied proportion of different prey categories: namely an increased proportion of aquatic prey and a decreased proportion of water vole and waterfowl. The increase in abundance of American mink saw a decrease in the proportion of larger prey in their diet. When American mink preyed more often on frogs, food niche overlap of both predators increased. This result suggests that arrival of an alien competitor reduced food abundance (exploitative competition) and caused a change in native mink diet.

The peculiarities of feeding of the American mink (Neovison vison) in the Southern Urals

The peculiarities of feeding of American mink in various waterbodies of the Southern Urals are described. The structure of the mink ration considerably depends on the type of water body. In all water bodies, fish, insects, and mammals were in the group of main forage; in lakes, mollusks or crayfish were added to this group. Birds and frogs in all water bodies were less important; reptiles (snakes) were accidental prey. It is revealed that the terrestrial mollusks played an important role in mink feeding. The differences in the structures of rations of the western and eastern populations of American mink were found.

Importance of the kidneys in metabolism of vitamins A 1 and A 2 and their fatty acyl esters in mink feeding on fish-based diets and exposed to Aroclor 1242

Two-month-old female mink ( Mustela vison) were fed diets based on freshwater smelt ( Osmerus eperlanus), Baltic herring ( Clupea harengus membras), or North-Atlantic herring ( Clupea harengus harengus) for 21 weeks. Half of the smelt-fed mink were exposed to the commercial polychlorinated biphenyl (PCB) preparation Aroclor 1242 (1 mg/day) in the feed. Retinol (vitamin A 1), 3,4-didehydroretinol (vitamin A 2), their fatty acyl esters, and vitamin E were studied in the kidneys by reversed-phase high-performance liquid chromatography. Exposure to Aroclor 1242 resulted a significant decrease in the alcoholic and esterified vitamin A 2. Levels of the A 1 analogs did not change due to the PCBs and were the same in mink fed either smelt or Baltic herring. In mink fed very fatty Atlantic herring, the renal levels of vitamin A 1 and E were significantly lower than in the other mink and apparently consumed by lipid peroxidation. The vitamins were located mainly in the cortex, and the fatty acyl esters showed a fatty acid composition that differed from those in liver and plasma. In the kidneys of the smelt-fed mink (control or Aroclor-exposed) the ratio of vitamin A 2 to A 1 was much lower than the ratios in the liver or plasma, suggesting inefficient uptake of A 2 in the kidneys. In the PCB-exposed mink, in which vitamin losses are increased, tissue levels of vitamin A 2 may be more difficult to maintain than levels of vitamin A 1.

Vitamins A1and A2in hepatic tissue and subcellular fractions in mink feeding on fish‐based diets and exposed to Aroclor 1242

Two-month-old female mink were fed diets based on either Baltic herring (Clupea harengus membras) or freshwater smelt (Osmerus eperlanus) for 21 weeks. A portion of the smelt-fed mink were exposed orally to polychlorinated biphenyls (PCBs), Aroclor 1242 (1 mg/d). Retinol (vitamin A1), 3,4-didehydroretinol (vitamin A2), and their different fatty acyl esters were studied in hepatic tissue, microsomes, and cytosol by argentated reversed-phase high-performance liquid chromatography. As a result of Aroclor exposure, concentrations of the fatty acyl esters of vitamins A1 and A2 were about one-tenth and those of unesterified A2 one-fourth those of the control levels. In the fatty acyl esters, percentages of stearates (A1--18:0 and A2--18:0) increased at the expense of the other fatty acyl esters. The Aroclor exposure decreased concentrations of alcoholic and esterified forms of the A2 analog more than those of the corresponding A1 analog. In microsomes. Aroclor decreased the alcoholic and esterified vitamin analogs to the same extent (to 9-17%). In the cytosol compared to the control, the concentrations of the vitamin esters fell below 10%, but the alcoholic analogs remained at 30 to 40%. Despite equal dietary supply, in mink fed on Baltic herring, the hepatic levels of vitamin A, were only about one-third of the values found in the smelt-fed mink. The organochlorines also altered hepatic lipid composition and impaired breeding and kit growth. In the kits of the females fed on Baltic herring, blood hemoglobin was decreased.

Effects of blocking farm mink's feed access with open water

Thirty-eight farm mink were used to investigate whether open water in some instances could be a barrier to farm mink. Half of the animals grew up with free access to swimming water in a basin, the other half to an empty middle cage. Access between the cage containing the nest box and the cage containing the feed was either through the basin/middle cage or through a tunnel above it. Twenty-four hours before observations, the animals were confined without feed to the cage containing the nest box. Observations were carried out over two and a half hours after re-opening one of the access routes to the feed. When access was through the water filled basin, the animals were slower in reaching the feed and crossed between the feed and the nest box fewer times compared to both the same animals using the tunnel and the animals having a dry middle cage. In addition, animals scratched more at the blocked tunnel access when the available route was through the water than when it was through the dry middle cage. The results led to the conclusion that, under some circumstances, water can act as a barrier when farm minks are approaching feed. This indicates that water for swimming is not necessarily an environmental enrichment for, and that the lack of it would not impair the welfare of ranch mink.;

Formic acid–sodium benzoate preserved slaughterhouse offal and supplementary folic acid in mink diet

Slaughterhouse offal from beef slaughtering was preserved with 16 g kg −1 formic acid and 3 g kg −1 sodium benzoate and used in mink feed throughout the production year. The ensiled offal replaced 0, 0.5 or 1.0 parts of the frozen stored slaughterhouse offal in the basal diet, the level of which was 300, 200 and 260 g kg −1 during growth-furring, breeding and lactation periods respectively. Because folic acid has a central role in formate metabolism and in all tissues of high rate of cellular division during the breeding and lactation periods, each diet group was further divided into two levels of supplemented dietary folic acid, 1.3 or 10 mg kg −1 DM. Weaning weights of male kits and lactating females, as well as early post-weaning growth and hemoglobin development were negatively affected by the highest silage level, providing 4.5 g formic acid kg −1 feed. The pelt quality of the groups that received silage was comparable to or even better ( p < 0.10) than that of the group of untreated, frozen stored offal. Both male and female reproduction performance was good and unaffected by the dietary manipulations. The effect of increased dietary folic acid could not be seen in any of the reproduction parameters or in pre-weaning kit growth. Extensive formation of free fatty acids in the silage due to high ash content of the offal and probable subsequent fat saponification are suggested to be among the factors that led to the slightly impaired growth performance of the animals, especially before weaning. In conclusion, ensiling of slaughterhouse offal with formic acid and sodium benzoate is an applicable preservation method and inhibits microbiological spoilage for several weeks. The lower performance of animals during lactation and early postweaning periods indicates that the high level of use of silage containing formic acid should be limited to the period from approximately 12 weeks of age to pelting.

Fatty Fish and Defatted Fish Products for Male Mink (Mustela vison) in the Growing-Furring Period: I. Effects on growth and pelt characteristics

Investigations on the use of fatty herring (Clupea harengus) scrap and mackerel (Scomber scombrus) (whole and scrap), and defatted herring scrap for male mink kits in the growing-furring periods were carried out in two consecutive years. Each year, three diets containing fatty herring scrap and three diets containing fatty mackerel, supplying 30, 50 or 70% of the dietary fat were compared with a control diet supplying only 20% of dietary fat as marine fat. In one of the experiments, another three groups were fed 12, 23 or 32% of defatted herring scrap in the diet. Each experimental group consisted of ∼75 male Scanglow mink kits. The energy content of the feed was 8.5 MJ kg-1 and there was ∼360 g crude protein per kg dry matter in all diets. When supplying up to a level of 50% of the fat from marine fat, the same or better weight gain, pelt length and fur quality in male mink kits were found compared with the control group. Increasing the proportion of dietary fat from herring scrap or mackerel up to 70% reduced both pelt length and fur quality compared with inclusion of 50% marine fat. Defatted herring scrap resulted in good pelt length and fur quality compared with the control group when used in proportions up to 32% of the diet, and the product is a good alternative feedstuff for mink feed.

Effects of feeding and short-term fasting on water and electrolyte turnover in female mink (Mustela vison).

Daily (24 h) rates of water and electrolyte turnover were measured in a conventional balance study in ten adult female pastel mink (Mustela vison) given free access to a standard mink feed for a 1-week conditioning period, followed by a 4 d experimental period and a 2 d fasting period. Drinking water was available throughout. In addition, the completeness of urine collection and the fraction of urine collected with the faeces were determined using a new experimental technique based on 24 h recoveries of specific urinary markers such as tritiated p-aminohippuric acid ([3H]PAH) or 14C-labelled inulin ([14C]IN) continuously delivered by small Alzet osmotic pumps implanted intraperitoneally. During feeding the mean individual percentage recovery in urine of [3H]PAH released from the osmotic pumps ranged from 68 to 88% (median 78%). The mean percentage of urinary [3H]PAH recovered from faecal collections was 6% (range 3-12%). In response to fasting the mean individual percentage recovery of [3H]PAH in urine ranged from 62 to 78% (median 68%). For urinary [14C]IN the mean percentage recoveries in fed and fasted animals were 79 and 63% respectively. Furthermore, during fasting, withdrawal of the supplies of dietary water caused a slight but insignificant (P = 0.17) increase in the daily intake of drinking water and, hence, the animals maintained their normal water balance by a dramatic reduction in urine excretion (P < 0.001). At the same time urinary solute excretion declined significantly (P < 0.001), due in part to the cessation of dietary electrolyte intake and in part to reduced formation of urea, whereas urinary osmolality decreased only moderately. The mean 24 h balances of Na, K, Ca, Mg, Cl and P were close to zero and only minor differences between the feeding and fasting periods were observed. When corrected for the measured inaccuracies in urine collection the balance data obtained in the present study represent useful reference standards for normally fed and fasted non-growing mink and, to some extent, useful guidelines for future studies in experimental animals.

Transmission studies with transmissible mink encephalopathy and bovine spongiform encephalopathy, and a survey of mink feeding practices

Transmission studies with transmissible mink encephalopathy and bovine spongiform encephalopathy, and a survey of mink feeding practices

Radiation pasteurization of mink feed: Effect of irradiated feed on reproductive performance, growth and fur quality of mink

No significant differences were observed in the net birth rate of kits/female between the 7 breeding groups. However, there was reduced incidence (P = 0.05) of kit deaths among the females receiving irradiated feed, and larger kit size (P < 0.0001) at birth particularly for the litter size of 5–8 kits. The second generation minks born to parents receiving feed irradiated to a planned dose of 1 kGy weighed on average about 2.5 % more, and their fur was on average about 1 ± 0.26 cm longer (12 % more males making the top length grade). Moreover, there was no effect of irradiated feed on fur quality. Irradiation of mink feed with subsequent frozen storage of the meat component improved the microbiological quality by decreasing the incidence of Pseudomonas sp. and Salmonella sp. Radiation pasteurization of mink feed (frozen meat to 1 kGy, and dry feed to 2 kGy or more) should therefore help improve feed utilization, keep the animals healthier, and reproducing better without affecting fur quality.