Prevalence of Brucella pinnipediae in healthy hooded seals (Cystophora cristata) from the North Atlantic Ocean and ringed seals (Phoca hispida) from Svalbard     

Tryland M  Sørensen KK  Godfroid J 《Veterinary microbiology》2005,105(2):103-111

Investigations for Brucella-infections were conducted in 29 hooded seals (Cystophora cristata) caught between Svalbard and Greenland (North Atlantic Ocean; Greenland Sea) autumn 2002, and from 20 ringed seals (Phoca hispida) caught in Billefjord, Svalbard, spring 2003. All animals were apparently healthy and were caught in their natural habitat. Bacteriology on tissue samples from ringed seals was negative, whereas Brucella sp. were recovered in tissues from 11 of the 29 hooded seals (38%), with the highest tissue prevalence in spleen (9/29) and lung lymph nodes (9/24). Anti-Brucella antibodies were detected in sera from 9 hooded seals (31%) (EDTA-modified Slow Agglutination test of Wright, Rose Bengal test, Complement Fixation Test, and Protein-A ELISA). The bacterial isolates all belonged to the genus Brucella according to classical biotyping and PCR analysis based on Insertion Sequence IS711, and were shown to be typical marine mammal strains, based on the occurrence of an IS711 element downstream of the bp26 gene. Their dependency on CO2 for growth, and the presence of one copy each of the omp2a and omp2b gene finally classified them as Brucella pinnipediae. Furthermore, all the hooded seal isolates showed an A+ M+ agglutination profile, which is different from the profile of reference seal strain 2/94 (harbour seal, Phoca vitulina). Thus, these results indicate that B. pinnipediae may contain different biovars. The present results suggest that infection with B. pinnipediae is enzootic in this population. Since the hooded seal is commercially hunted and consumed in Norway, the pathological impact of such infections and their zoonotic potential should be further addressed.  相似文献   

Activity patterns of free-ranging beef cattle in Norway     

Morten Tofastrud  Hilde Hegnes  Olivier Devineau  Barbara Zimmermann 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2018,68(1):39-47

The aims of this study were to: 1) build a model to classify cattle activities based on locomotion and neck movement data and 2) study the daily time budget of non-native beef cattle in the boreal forest of southeastern Norway. We used GPS collars programmed to take positions and activity measures every five minutes on 18 cows during the grazing seasons 2015–17, together with behavioural observations in the field. The model classified the collar data into Grazing, Low (resting behaviours) and High (other active behaviours) activity with an accuracy of 79.4%. The cows spent 8.1?±?0.5 (mean?±?SD) hours per day grazing, corresponding to 34%?±?0.5% of their daily time budget. Daily grazing time increased during summer and was longer for lactating than dry cows and at low compared to high stocking density.  相似文献   

dl‐methionine enrichment in diets fed to Atlantic salmon increases apparent digestibility     

Marit Espe  Bjørn Liaset  Ernst Morten Hevrøy  Adel El‐Mowafi 《Aquaculture Research》2011,42(8):1123-1130

In the current study, we tested whether the addition of a small amount of crystalline dl ‐methionine to a fishmeal‐based diet would affect general sulphur metabolism and apparent digestibility in Atlantic salmon (Salmo salar). Triplicate tanks of salmon with mean BW of half a kilo were fed a control diet or the control diet supplemented with 0.2 wt%dl ‐methionine (+17% methionine relative to control diet) for a period of 3 months. Feed intake and thus nutrient intake did not differ significantly between treatments. Fish fed the diet supplemented with dl ‐methionine had 18% higher mean intake of methionine. The apparent energy digestibility was significantly improved in the salmon fed the methionine‐enriched diet as was the methionine digestibility. Salmon fed the methionine‐supplemented diet had about 32% higher plasma‐free methionine concentration and 25% more total homocysteine 5 h post prandial. No difference was observed in hepatic‐free methionine, but hepatic cystathionine (～62%) and taurine (～20%) were significantly higher in fish fed the methionine‐enriched diet due to a higher transsulphuration. In the liver, taurine might be conjugated to bile acids (BAs), and conjugation of BAs increases their solubility and enhances their biliary secretion affecting the digestibility. Both faecal and plasma BA concentrations were elevated in fish fed the methionine‐enriched diet, although the differences did not reach statistical significance. Taken together, our data show that feeding salmon a fishmeal‐based diet supplemented with a small amount of crystalline dl ‐methionine increased the apparent energy digestibility, possibly through an increased liver transsulphuration and taurine production, which might enhance BA conjugation and biliary secretion.  相似文献   

Breeding for disease resistance of Penaeid shrimps     

James Cock  Thomas Gitterle  Marcela Salazar  Morten Rye 《Aquaculture (Amsterdam, Netherlands)》2009,286(1-2):1-11

Diseases are a major constraint on the intensive production of shrimps. Conditions in production ponds favour disease development, and epidemics of several previously unreported diseases have occurred and caused severe losses. When elimination, eradication or cultural control is difficult, selective breeding for host resistance to the pathogen may be an attractive option for disease control. However, host resistance is not a panacea and should only be considered when (a) the disease causes severe damage (b) there are no other existing simple cost effective control measures and (c) there is demonstrable genetic variation in resistance and this is not coupled with an excessive level of negative associations with other desirable characteristics. Shrimp have only recently been domesticated and breeding for resistance only began in the mid 1990s; there is limited experience with shrimp breeding in particular and crustaceans in general. Consequently, the principles and concepts behind breeding programmes are based largely on experiences with other species in both the plant and animal kingdoms. Commercial growers now seed ponds with shrimp populations selected for resistance to Taura Syndrome Virus with excellent results, whilst up to now development of White Spot Syndrome Virus resistant populations has been an elusive goal. The original TSV resistant populations were developed using simple mass selection techniques (Colombia). In later generations family based selection has been applied on populations, which initially had survival rates of about 30%, with care taken to reduce inbreeding and loss of genetic variation. This suggests that when the original populations have a reasonable level of resistance, and straightforward, effective selection protocols exist, it is relatively simple to breed for resistance. With catastrophic diseases, such as WSSV, which cause mortalities of 98% or more the frequency of resistance is low and it is suggested that for theoretical reasons single gene, rather than polygenic, resistance is likely to develop. The low frequency of resistance genes in breeding populations may cause genetic bottlenecks which will greatly reduce the genetic variation in the populations. In order to maintain the genetic variation the genes from the small numbers of survivors should be introgressed into populations with broader genetic variability. Furthermore, in order to minimize the probability of breakdown of resistance pyramiding of resistant genes on different loci would be advantageous.Genetic variation in resistance may be encountered either in the initial base populations or may spontaneously arise due to mutations or new recombinants. With extremely prolific species such as shrimps, millions of animals can readily be screened for survival and hence resistant mutants or recombinants may be identified. Once genetic variation has been detected the most appropriate breeding methodology will depend on the nature of both the resistance and the disease or diseases that are of interest to the producers.  相似文献   

Is European research on aquatic food product technology dead?     

Morten Sivertsvik 《Journal Of Aquatic Food Product Technology》2019,28(1)

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Serum chemistry of free-ranging white whales (Delphinapterus leucas) in Svalbard     

Tryland M  Thoresen SI  Kovacs KM  Lydersen C 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):199-203

BACKGROUND: Abnormal physiological conditions and diseases can change the concentrations of enzymes, metabolites, and minerals in the body. Serum chemistry information may thus be indicative of a specific disease; interpretation of such information requires knowledge of serum chemistry reference intervals from a seemingly healthy population of the species. OBJECTIVE: The aim of this study was to obtain serum chemistry reference intervals for a population of white whales. METHODS: Blood samples were collected from 21 free-ranging white whales (beluga; Delphinapterus leucas). The whales were live-captured in nets during 1996-2001 in Storfjorden, Van Mijenfjorden, and Van Keulenfjorden (Svalbard, Norway). While the whales were briefly physically restrained, blood was collected from the caudal vein into vacuum tubes without anticoagulant. The blood was left to clot for 4-6 hours before serum was obtained by centrifugation. The serum samples were then kept at -20 degrees C until analysis. Enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase [ALP], creatine kinase, lactate dehydrogenase [LDH], amylase, lipase), metabolites (urea, creatinine, bilirubin, cholesterol, triglycerides, nonesterified fatty acids, glucose), and minerals (calcium, phosphate, magnesium, sodium, potassium, chloride) were analyzed in an Advia 1650 System (Bayer, Tarrytown, NY, USA). Cortisol was analyzed in an Immulite One system (Diagnostic Products Corporation, Los Angeles, CA, USA). The major blood proteins (albumin and globulins) were separated by gel electrophoresis in a Beckman Paragon electrophoresis system (Beckman Coulter, Inc., Fullerton, CA, USA). RESULTS: Serum values for all analytes were reported as median and range, and reference intervals were calculated as 10-90th percentiles. Activities of ALP and LDH and cortisol concentration were higher, and protein and bilirubin concentrations were lower compared with those previously reported for white whales from Canada; remaining results were strikingly similar in these 2 white whale populations. CONCLUSIONS: These data provide valuable serum chemistry reference intervals for future health assessments of white whales in Svalbard and other white whale populations, as well as captive individuals.  相似文献   

Molecular mapping of partial resistance to powdery mildew in winter wheat cultivar Folke     

Morten Lillemo  ?smund Bj?rnstad  Helge Skinnes 《Euphytica》2012,185(1):47-59

The Swedish winter wheat (Triticum aestivum L.) cultivar Folke has a long record of partial and race non-specific resistance to powdery mildew (caused by Blumeria graminis f. sp. tritici) in the field. The aim of the present study was to map the main genetic factors behind the partial resistance in Folke and identify molecular markers for use in marker-assisted selection. A population of 130 recombinant inbred lines was developed from a cross between Folke and the moderately susceptible spring wheat line T2038. The population was tested for powdery mildew resistance over two years at two locations in Norway and genotyped with DArT and SSR markers. Composite interval mapping detected a total of eight quantitative trait loci (QTL) for powdery mildew resistance; six with resistance from Folke on 2BS, 2DL, 5AL, 5BS and 6BS and two with resistance from T2038 on 5BS and 7AL. None of the loci with resistance from Folke mapped to chromosomal regions with known race-specific resistance genes, which confirmed the race non-specific nature of the resistance in this cultivar. The molecular markers linked to the reported QTL will be useful as a tool for selecting partial and potentially durable resistance to powdery mildew based on the resistance in Folke.  相似文献   

Phosphorus dynamics and export in streams draining micro‐catchments: Development of empirical models     

Brian Kronvang  Marianne Bechmann  Morten L. Pedersen  Nicola Flynn 《植物养料与土壤学杂志》2003,166(4):469-474

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Estimation of conversion factors for fungal biomass determination in compost using ergosterol and PLFA 18:2ω6,9     

Morten Klamer  Erland Bååth 《Soil biology & biochemistry》2004,36(1):57-65

Eleven species of common fungi from compost were analysed for their content of ergosterol and phospholipid fatty acids (PLFAs) after growth on agar media. Mean content of ergosterol was 3.1 mg g⁻¹ dw of fungal mycelium (range 1-24 mg g⁻¹ dw). Total amount of PLFAs varied between 2.6 and 43.5 μmol g⁻¹ dw of fungi (mean 14.9 μmol g⁻¹ dw). The most common PLFAs were 16:0, 18:2ω6,9 and 18:1ω9, comprising between 79 and 97 mol% of the total amount of PLFAs. The PLFA 18:2ω6,9, suggested as a marker molecule for fungi, comprised between 36 and 61 mol% of the total PLFAs in the Ascomycetes, between 45 and 57 mol% in the Basidiomycetes and 12-22 mol% in the Zygomycetes. There was a good correlation between the content of the two fungal marker molecules, ergosterol and the PLFA 18:2ω6,9, with a mean content of 1 mg ergosterol being equivalent to 2.1 μmol of 18:2ω6,9. Based on results from the fungal isolates, conversion factors were calculated (5.4 mg ergosterol g⁻¹ biomass C and 11.8 μmol 18:2ω6,9 g⁻¹ biomass C) and applied to compost samples in which both the ergosterol and the PLFA 18:2ω6,9 content had been measured. This resulted in similar estimates of fungal biomass C using the two marker molecules, but was three to five times higher than total microbial biomass C calculated using ATP content in the compost. This could partly be explained by the fact that both of the markers used for fungal biomass are cell membrane constituents. Thus, the ergosterol and the PLFA content were related to the hyphal diameter of the fungi, where fungi with thinner hyphae had higher ergosterol concentrations than fungi with thicker hyphae. This could also partly explain the large interspecific variation in content of the two marker molecules.  相似文献   

Pre-Clovis mastodon hunting 13,800 years ago at the Manis site, Washington     

Waters MR  Stafford TW  McDonald HG  Gustafson C  Rasmussen M  Cappellini E  Olsen JV  Szklarczyk D  Jensen LJ  Gilbert MT  Willerslev E 《Science (New York, N.Y.)》2011,334(6054):351-353

The tip of a projectile point made of mastodon bone is embedded in a rib of a single disarticulated mastodon at the Manis site in the state of Washington. Radiocarbon dating and DNA analysis show that the rib is associated with the other remains and dates to 13,800 years ago. Thus, osseous projectile points, common to the Beringian Upper Paleolithic and Clovis, were made and used during pre-Clovis times in North America. The Manis site, combined with evidence of mammoth hunting at sites in Wisconsin, provides evidence that people were hunting proboscideans at least two millennia before Clovis.  相似文献