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Infection with Aleutian mink disease virus (AMDV) has negative effects on reproductive performance and survival rate of American mink (Neovison vison). The objectives of this study were to assess the effects of kelp (Ascophylum nodosum) supplementation on survival, growth rate and reproductive performance of mink challenged with AMDV. AMDV-free female black mink (n=75) were intranasally inoculated with a local AMDV strain. Mink were fed a commercial pellet supplemented with 1.5% or 0.75% kelp or were kept as controls (received no kelp) for 451 days. Body weight and rectal temperature were recorded on days 0, 31, 56, 99, 155, 366 and 451 post-inoculation (PI). Annual mortality rates were 13.6%, 20.0% and 31.8% for mink fed 1.5%, 0.75% or 0.0% kelp, respectively (P=0.29). Mink which were fed 1.5% kelp had a significantly (P<0.01) greater daily weight loss during breeding and post-breeding periods (days 155 to 366 PI), and outperformed (P<0.01) the other groups in regard to litter sizes at birth and weaning. Differences among treatments were not significant for the number of females mated or whelped of those exposed to males, kit survival from birth to weaning or rectal temperature. It was concluded that 1.5% kelp supplementation had beneficial effects on survival rate of adult mink and litter size.

White, M. B., Anderson, D. M. and Rouvinen, K. I. 1999. Apparent digestibility coefficients of raw ground, acid and fermented silver hake (Merluccius bilinearis) feedstuffs for mink and an evaluation of the storage stability of the silages. Can. J. Anim. Sci. 79: 375-381. A 3 × 4 factorial design experiment was conducted to determine digestibility coefficients (DC) of dry matter (DM), crude protein (CP), crude fat (CF), gross energy (GE) and amino acids (AA) in raw ground silver hake (RGSH), acid (ASHS) and fermented (FSHS) silver hake silages for mink. The ASHS was prepared with the addition of 2.5% (wt:wt) formic acid (85% concentration) and 200 ppm antioxidant (ethoxyquin) to the raw ground fish. The FSHS was produced with the addition of 1% Marisil ® (Finn Sugar), 15% extruded wheat and 1% (wt:wt) formic acid (conc. 85%) to the raw ground fish. Twelve mature standard type male mink were confined to metabolism cages during the digestibility trial, which consisted of three experimental periods comprised of a 6-d adjustment period, followed by a 5-d collection period. Based on the total collection (TC) method and with graded levels (0, 15, 30 and 45%) of the test feedstuffs in the experimental diets, nutrient digestibilities in the pure feedstuffs were determined using a mathematical regression technique. The apparent digestibility (AD) of DM, CP, CF and GE were RGSH: 88.4, 93.6, 99.2 and 94.7%; ASHS: 90.6, 85.8, 96.1 and 87.2% and FSHS: 77.7, 84.5, 99.2 and 86.1%, respectively. The AD of all the AAs, except proline, in the RGSH was significantly higher (P < 0.05) than that in the ASHS and FSHS. A quality evaluation of the silages was conducted in a completely randomized design with two replications to determine storage stability of the silages, on 10 different sampling days, (3 sampling days for AAs), over the storage period. Quality of the silages was stable up to 90 days for the ASHS and 180 days FSHS based on increases in pH and total volatile nitrogen (TVN) content and decreases in N and AA content. The silver hake feedstuffs would provide a good source of highly digestible nutrients for mink and should be considered as opportunity feeds for these animals. 88,4, 93,6, 99,2 et 94,7 %; pour EA à 90,6, 85,8, 96,1 et 87,2 % et pour EF à 77,7, 84,5, 99,2 et 86,1 %. La DA de tous les AA, sauf la proline, était significativement plus forte (P < 0,05) dans le cas de BC que dans ceux de EA et de EF. Nous avons ensuite exécuté une évaluation qualitative des ensilages selon un dispositif complètement aléatoire à deux répétitions pour déterminer la stabilité à la conservation des ensilages préparés à 10 jours de prélèvement différents (3 seulement pour les AA) durant la période de garde. La stabilité se maintenait jusqu'à 90 jours dans le cas de EA et à 180 j dans celui de EF d'après les augmentations du pH et des teneurs en azote volatil total (NVT) et les diminutions des teneurs en N et en AA. Les aliments préparés à partir du merlu argenté paraissent une bonne source de nutriments hautement digestibles pour le vis...

White, M. B., Anderson, D. M. and Rouvinen, K. I. 1998. Digestibility by mink and storage stability of feedstuffs made from raw ground, acid-treated or fermented dogfish (Squalus acanthias). Can. J. Anim. Sci. 78: 633-640. Dogfish was evaluated in a 3 × 4 factorial design experiment conducted to determine digestibility coefficients (DC) of dry matter (DM), crude protein (CP), crude fat (CF), gross energy (GE) and amino acids (AA) in raw ground dogfish (RGD), acid (ASD) and fermented (FSD) dogfish silages for mink. The ASD was prepared with the addition of 2.5% (wt:wt) formic acid (conc. 85%) and 200 mg kg -1 antioxidant (ethoxyquin) to the raw ground fish. The FSD was produced with the addition of the commercial biopreservative Marisil ® , (Finn Sugar) (1%) and extruded wheat (15%) to the raw ground fish. In the digestibility trial, consisting of three, 11-d periods, each having a 6-d adjustment followed by a 5-d collection, 12 mature standard type mink were confined to metabolism cages. Using the total collection (TC) method, where graded levels (0, 15, 30 and 45%) of the test feedstuff were substituted into a basal diet, an extrapolation using regression analysis was done to estimate digestibility of each test feedstuff. The AD of DM, CP, CF and GE was RGD: 81.8, 92.2, 96.2 and 89.6%; ASD: 87.1, 92.6, 100.0 and 93.2%; FSD: 86.0, 93.3, 98.1 and 90.4%, respectively. The AD of AAs was generally highest in the fermented dogfish feedstuff. A quality evaluation of the silages was conducted in a completely randomized design with four replications (two replications for AAs), to determine storage stability of the silages, on 10 different sampling days (days 1, 3, 6, 9, 15, 30, 90, 180, 270 and 360), (three sampling days for AAs) post-manufacture. The ASD was stable up to 180 d, after this storage time it underwent increases in pH and total volatile nitrogen (TVN) and decreases in N and AA content. The preservation of dogfish with a fermentation method (FSD) was judged to be unsuccessful with this feedstuff having a high initial pH (6.4) and large increases in TVN content early in storage. It was concluded that feedstuffs made from dogfish would provide a source of highly digestible nutrients for mink; however, more research is required before a fermented dogfish feedstuff can be incorporated into practical mink diets. , 3, 6, 9, 15, 30, 90, 180, 270 et 360 jours (3 dates seulement pour les AA) après la fabrication. L'ensilage acide demeurait stable jusqu'à 180 jours de conservation, après quoi son pH et les concentrations en N volatil total (NVT) augmentaient et les teneurs en N total et en AA diminuaient. La conservation du poisson par fermentation (RF) était jugée insatisfaisante, l'aliment ayant un pH initial élevé (6,4) et acquérant des teneurs en élevées en NVT dès le début de la conservation. Les aliments confectionnés à partir de chair de roussette constitueraient donc une bonne source de nutriments hautement digestibles pour le vison. Les recherches devront toutefois se poursuivent avant qu'on puisse recomman...