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1.
Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis/E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.  相似文献   
2.
Atlantic salmon (Salmo salar L.) females (2 SW), maturing for the first time, were reared under one of three temperature regimes (high: 14.3 ± 0.5°C; natural: 10.6 ± 1.0°C; and cold: 6.9 ± 1.0°C) in combination with one of two experimental treatments; an injection of GnRH analogue (GnRHa) contained in biodegradable microspheres, or a sham injection (microspheres only). The six experimental groups were then reared under simulated natural photoperiod for 4 weeks. Blood samples were drawn for analysis of plasma steroid levels and the fish were inspected for ovulation weekly. Batches of stripped eggs were incubated in triplicate incubators in raceways until the eyed stage. Treatment with GnRHa resulted in a substantial advancement and synchronization of ovulation at all temperatures, while exposure to cold water also appeared to advance ovulation slightly. While 75% (warm and cold) to 90% (natural) of GnRHa fish ovulated during the 4-week trial, only 30% of sham-treated females exposed to cold water, and none of the sham-treated fish held at higher temperatures, ovulated during this period. Survival rates of embryos to the eyed-stage were significantly higher for broodstock exposed to cold water. Plasma levels of testosterone (T), 17β-oestradiol (E2), and 17α,20β-dihydroxy-4-pregnen-3-one (17,20βP) were all significantly affected by treatment with GnRHa and, to a lesser extent, temperature. The efficiency of GnRHa in counteracting the negative effects of high temperature on ovulation and the associated changes in circulating sex steroids suggest that temperature inhibition operates at least in part at the brain or pituitary.  相似文献   
3.
Photoperiod and temperature modulated the seasonal pattern of ovarian gene expression of P450 aromatase, Follicle-Stimulating Hormone receptor and Luteinizing Hormone receptor in Atlantic salmon broodstock.  相似文献   
4.
Plasma vitamin D and vitamin D metabolites were measured in Atlantic salmon parr during smoltification and after transfer to seawater. The fish were fed commercial feed for 5 months under natural light, and Na+/K+ ATPase was measured as an indicator of the smoltification status. No significant differences were recorded in the level of plasma vitamin D metabolites. However, a tendency of increasing plasma concentration of 25OHD3 and also a temporary increase in plasma 1,25(OH)2D3 and 24,25(OH)2D3 were recorded prior to seawater transfer. The minor changes in plasma levels of the metabolites indicate a role of the vitamin D metabolites during parr–smolt transformation, although we do not know whether the increased levels are caused by increased synthesis of the metabolites or by decreased binding to receptors or decreased excretion.  相似文献   
5.
Cerebrospinal elaphostrongylosis in sheep in northern Norway.   总被引:2,自引:0,他引:2  
Pathologic examination of four sheep from northern Norway exhibiting neurologic signs of paresis, paralysis and vestibular system disease revealed nematodes in the central nervous system (CNS). The worms were identified as Elaphostrongylus rangiferi Mitskevich, 1960, the elaphostrongylid nematode of reindeer (Rangifer tarandus tarandus). Microscopic lesions found in the CNS were focal traumatic encephalomyelomalacia caused by migrating worms, eosinophilic meningitis and choroiditis, lymphohistiocytic and nematode granulomas, and perineural infiltrations. The disease occurred in November and December 1990, after the sheep had been on pasture in areas frequented by considerable numbers of reindeer.  相似文献   
6.
Until the 1970’s, Trichinella spiralis (Owen 1835) was considered the only species within the genus Trichinella. Then T. pseudospiralis (Garkavi 1972) was classified as a separate species on the basis of morphological and biological features. The remaining morphologically homogenous “T. spiralis-group” has been split into 4 different species (or subspecies) on the basis of their biological and biochemical characteristics; T. nativa (Britov & Boev 1972), T. nelsoni (Britov & Boev 1972), T. spiralis sensu stricto and T. britovi (Pozio et al. 1992).  相似文献   
7.
Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis / E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study.  相似文献   
8.
9.
Faecal samples were collected from 1,190 wild cervids in Norway and analyzed for cysts/oocysts of the protozoan parasites Giardia and Cryptosporidium. Samples were from calves, yearlings and adults of moose (Alces alces), red deer (Cervus elaphus), roe deer (Capreolus capreolus) and reindeer (Rangifer tarandus) shot during the hunting season. Cryptosporidium was found in 15 (3.3%) of 455 moose, 1 (0.3%) of 289 red deer, 18 (6.2%) of 291 roe deer, but was not found in any of 155 reindeer. Giardia was found in 56 (12.3%) moose, 5 (1.7%) red deer, 45 (15.5%) roe deer and 11 (7.1%) reindeer. The calves had the highest prevalence of infection, but this was only statistically significant for Giardia in moose and for Cryptosporidium and Giardia in roe deer. Calves generally had the highest intensity of infection, but this difference was only statistically significant for calves with Giarda and the highest intensity of infection. Both Giardia and Cryptosporidium were found in samples from several geographical areas, indicating that these parasites are distributed among the cervid population in all parts of Norway, especially in moose and roe deer. This is the first published report of Cryptosporidium in moose and of Giardia in reindeer.  相似文献   
10.
A new nutrient‐based evaluation system for feedstuffs and pig diets is proposed. The proposed system is based on (i) an identification of those organic nutrient fractions that, according to their absorption, metabolism and utilization, are relevant for determining the value of the feed, and (ii) biochemically‐based calculations of the potential physiological value of these fractions. The system is further based on a flexible stepwise evaluation in which the fundamental properties of the feed are related to its utilization in actual situations. Step 1 is characterized by single feedstuffs according to the digestible amounts of those nutrient fractions which are relevant for feed formulation, i.e. essential amino acids, other N‐compounds, ileal digestible carbohydrates, fermentable carbohydrates, fatty acids and other lipid compounds. Step 2 involves complete diets with three complementary properties, measured according to their potential value for the pig: protein value (i.e. amount of digestible ideal protein), “fat value”; (i.e. amount of digestible triacylglycerols) and the “complemental energy value”; (i.e. potential metabolic energy generated directly from the residual digestible nutrient fractions). Step 3 predicts the production value, either a standardized value determined by standard mathematical equations, or the actual value determined by the use of computerized pig models.  相似文献   
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