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A Lillehaug

Publications and source records attributed to A Lillehaug.

11 recordsLinked to original sources
PubMed2006

Food safety hazards that occur during the production stage: challenges for fish farming and the fishing industry.

Seafood derived from wild fish as well as farmed fish has always been an important source of protein in the human diet. On a global scale, fish and fish products are the most important source of protein and it is estimated that more than 30% of fish for human consumption comes from aquaculture. The first part of this paper outlines the hazards and challenges associated with handling fish during farming and capture. The authors describe infectious agents that cause disease in fish as well as humans, zoonotic agents, intoxications due to bacteria and allergies caused by the consumption of fish. Although only a few infectious agents in fish are able to infect humans, some exceptions exist that may result in fatalities. However, the greatest risk to human health is due to the consumption of raw or insufficiently processed fish and fish products. The second part of the paper considers environmental contaminants in seafood that may pose a risk to human health, such as medicinal products and residues associated with aquaculture, persistent lipophilic organic compounds and metals (methyl-mercury, organotin). The authors include an updated overview of the various factors associated with farmed and captured fish that may cause risks to human health after consumption. Moreover, they discuss the challenges (in the widest sense) associated with handling fish during capture and farming, as well as those encountered during processing.

Animals↗
PubMed2005

Screening of feral pigeon (Colomba livia), mallard (Anas platyrhynchos) and graylag goose (Anser anser) populations for Campylobacter spp., Salmonella spp., avian influenza virus and avian paramyxovirus.

A total of 119 fresh faecal samples were collected from graylag geese migrating northwards in April. Also, cloacal swabs were taken from 100 carcasses of graylag geese shot during the hunting season in August. In addition, samples were taken from 200 feral pigeons and five mallards. The cultivation of bacteria detected Campylobacter jejuni jejuni in six of the pigeons, and in one of the mallards. Salmonella diarizona 14: k: z53 was detected in one graylag goose, while all pigeons and mallards were negative for salmonellae. No avian paramyxovirus was found in any of the samples tested. One mallard, from an Oslo river, was influenza A virus positive, confirmed by RT-PCR and by inoculation of embryonated eggs. The isolate termed A/Duck/Norway/ 1/03 was found to be of H3N8 type based on sequence analyses of the hemagglutinin and neuraminidase segments, and serological tests. This is the first time an avian influenza virus has been isolated in Norway. The study demonstrates that the wild bird species examined may constitute a reservoir for important bird pathogens and zoonotic agents in Norway.

Animals↗
PubMed2005

Campylobacter spp., Salmonella spp., verocytotoxic Escherichia coli, and antibiotic resistance in indicator organisms in wild cervids.

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.

Animals↗
PubMed2003

Epidemiology of bacterial diseases in Norwegian aquaculture--a description based on antibiotic prescription data for the ten-year period 1991 to 2000.

In Norway, antibacterial drugs for use in farmed fishes have to be prescribed by a veterinarian. Moreover, a national surveillance programme requires that copies of all prescriptions be sent to the Directorate of Fisheries. The prescriptions give information regarding fish farm and locality, weight and species of fish to be medicated, diagnosis, type and amount of drug prescribed, and date. These prescription data for the 10 yr period 1991 to 2000 have been recorded and systematised. A total of 6322 prescriptions issued for 11 fish species were registered; Atlantic salmon represented 87% of the prescriptions, rainbow trout 4.5%, arctic char 0.3%, turbot 3.8%, halibut 2.1%, Atlantic cod 1.2%, and European eel 0.3%. European sea-bass, wolf-fish, coalfish and wrasse represented a total of 0.4% of the prescriptions. Furunculosis was the most frequently given diagnosis in Atlantic salmon, accounting for 79% of all prescriptions for this species. Furunculosis was more frequent during the summer and early autumn, and in the western parts of Norway. Fish weighing more than 1 kg seemed to be the most susceptible. However, furunculosis has almost disappeared in Norwegian aquaculture since 1993. Vibriosis gave cause for antibiotic treatments in almost all fish species, and was the most common diagnosis in rainbow trout, halibut, turbot, cod and European eel. In Atlantic salmon, fish of small and medium size (up to 1 kg) seemed to be more at risk from vibriosis, and outbreaks were more frequent during summer, and in the western counties. Cold-water vibriosis was the second most frequently treated disease in Atlantic salmon, creating severe problems mainly in larger fish, in the northern parts of the country, and during winter and spring. The seasonal distribution was similar for winter ulcer disease, the only disease which seemed to be of increasing importance in Atlantic salmon. Non-specific diagnoses, such as 'bacterial infection' and 'fry disease', were given in a much higher proportion of prescriptions for marine fish species than in prescriptions for salmonids.

Animals↗
PubMed1999

Recent developments in fish vaccinology.

During the last 10 to 20 years vaccination has become established as an important method for prevention of infectious diseases in farmed fish, mainly salmonid species. So far, most commercial vaccines have been inactivated vaccines administered by injection or immersion. Bacterial infections caused by Gram-negative bacteria such as Vibrio sp., Aeromonas sp., and Yersinia sp. have been effectively controlled by vaccination. With furunculosis, the success is attributed to the use of injectable vaccines containing adjuvants. Vaccines against virus infections, including infectious pancreatic necrosis, have also been used in commercial fish farming. Vaccines against several other bacterial and viral infections have been studied and found to be technically feasible. Pasteurellosis, streptococcosis (lactococcosis) and infections with iridoviruses are candidate diseases for control by immunoprophylaxis in the near future. The overall positive effect of vaccination in farmed fish is reduced mortality. However, for the future of the fish farming industry it is also important that vaccination contributes to a sustainable biological production with negligible consumption of antibiotics. A potential side-effect associated with injectable vaccines is local reactions in the peritoneal cavity. The paper presents recent developments in immunoprophylaxis of fish and some problems that should be addressed by the research community in the years to come.

Animals↗
PubMed1999

Prudent use of antibacterial drugs in Norwegian aquaculture? Surveillance by the use of prescription data.

Antibacterial drug treatment in aquaculture during 1991-1996 was investigated using prescription data provided by the Norwegian Government Fish Inspection and Quality Control Service (NFCS). The majority of prescriptions (n = 5401) were for Atlantic salmon and rainbow trout (salmonids), while 383 prescriptions were for other species. Of the 13 different single substances or combinations prescribed during the study period, only 5 were approved for or had been subjected to clinical trials in salmonids. Of the prescriptions for the salmonids, 99% were for approved drugs or drugs subjected to clinical trials. The major proportion of the antibacterial drugs prescribed for other fish species were drugs which were approved for or which had been subjected to clinical trials in salmonids. In all fish species, the prescribing of antibacterial drugs which were neither approved for nor had been subjected to clinical trials was mainly for fish far below slaughter weight. The prescription data were validated against the drug statistics from the wholesalers and feed mills. It was concluded that the data indeed represented antibacterial drug prescribing in Norwegian aquaculture. The prescribing of antibacterial drugs proved to be almost completely reported to NFCS, which is responsible for the control of drug residues in farmed fish in Norway.

Animals↗
PubMed1998

Growth of Atlantic salmon Salmo salar after intraperitoneal administration of vaccines containing adjuvants.

Growth of Atlantic salmon after intraperitoneal (i.p.) administration of adjuvanted vaccines was studied using groups of individually tagged fish held together in one tank or pen under commercial farming conditions. Parallel experiments were initiated at 2 freshwater sites and 1 marine site. Trivalent (vibriosis, cold water vibriosis and furunculosis) vaccines containing oil or beta-1, 3 glucan as adjuvants were used for immunisation of pre-smolts, whereas identical formulations containing furunculosis antigens only were used in growers. Control fish remained unvaccinated. No outbreak of bacterial or viral disease was experienced at any of the sites. At all sites, the highest daily growth rate was recorded in unvaccinated fish. At one site, the average weight of post-smolts that had received oil-adjuvant vaccine was significantly reduced by 345 g (23%) after 15 mo. Impaired growth rate was associated with increasing severity of intra-abdominal lesions as determined during necropsy. At the second post-smolt site and in growers, weight development and growth rates were non-significant between groups throughout the study. The results indicate that intraperitoneal administration of oil-adjuvanted vaccines may retard growth of farmed Atlantic salmon, although the extent of this effect may vary between sites. Unidentified factors coinciding with vaccination are thought to have caused the highly variable results seen between parallel sites in this study.

Adjuvants, Immunologic↗
PubMed1997

Vaccination strategies in seawater cage culture of salmonids.

Successful vaccination depends both on the development of protective vaccines and their correct use. In addition to deciding which diseases to vaccinate against, the choice of the method, timing, and use of revaccination must be considered. In seawater culture of salmonids, vibriosis and furunculosis are the most important diseases against which to vaccinate in many parts of the world, while cold-water vibriosis is of great significance in Atlantic salmon in some areas with low water temperatures. A vaccine against infectious pancreatic necrosis (IPN) has also been introduced recently. For optimal protection of salmonids in sea-water, vaccination should be carried out some time before sea transfer, in order to give immunity sufficient time to develop, and to avoid handling stress during smoltification. On the other hand however, vaccination should not be carried out too early, as the degree of immunity declines with time. Water temperature is an important factor when deciding when to vaccinate. Recent research has demonstrated that Atlantic salmon may be vaccinated successfully at low water temperatures. In general, vaccination by the injection method gives superior protection. Vaccines against the Vibrio-infections can also be administered successfully by immersion. However, due to lower levels of immunity, the need for a booster vaccination is greater when such a method is used. As regards vaccines against furunculosis, adjuvants are needed in order to achieve good protection, and, consequently, administration by injection is the only option.

Aeromonas↗
PubMed1991

Characterization of Vibrio anguillarum and closely related species isolated from farmed fish in Norway.

A total of 264 bacterial strains tentatively or definitely classified as Vibrio anguillarum were examined. The strains were isolated from diseased or healthy Norwegian fish after routine autopsy. With the exception of five isolates from wild saithe (Pollachius virens), the strains originated from nine different species of farmed fish. The bacteria were subjected to morphological, physiological, and biochemical studies, numerical taxonomical analyses, serotyping by slide agglutination and enzyme-linked immunosorbent assay, DNA-plasmid profiling, and in vitro antimicrobial drug susceptibility testing. The results of the microbiological studies were correlated to anamnestic information. The bacterial strains were identified as V. anguillarum serovar O1 (n = 132), serovar O2 (n = 89), serovar O4 (n = 2), serovar O8 (n = 1), and not typeable (n = 1) as well as Vibrio splendidus biovar I (n = 36) and biovar II (n = 1), Vibrio tubiashii (n = 1), and Vibrio fischerii (n = 1). V. anguillarum serovar O1 or O2 was isolated in 176 out of 179 cases of clinical vibriosis in Atlantic salmon (Salmo salar). V. anguillarum serovar O1 was the only serovar isolated from salmonid fish species other than Atlantic salmon, while V. anguillarum serovar O2 was isolated from all marine fish suffering from vibriosis. A 48-Mda plasmid was isolated from all V. anguillarum serovar O1 isolates examined. Serovar O2 isolates did not harbor any plasmids. Resistance against commonly used antibiotic compounds was not demonstrated among V. anguillarum isolates. Neither V. splendidus biovar I nor other V. anguillarum-related species appeared to be of clinical importance among salmonid fish.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

Vaccination in European salmonid aquaculture: a review of practices and prospects.

Disease control by vaccination is widely used in European salmonid aquaculture against vibriosis (Vibrio anguillarum), cold-water vibriosis (Vibrio salmonicida), yersiniosis or enteric redmouth disease (Yersinia ruckeri) and furunculosis (Aeromonas salmonicida subsp. salmonicida). The vaccines against the Vibrio spp. and Y. ruckeri have proven effective especially when administered by injection. Furunculosis vaccines have been less successful and have relied on combination with potent adjuvants to achieve acceptable protection. Application of modern molecular techniques to furunculosis research has delivered a crop of experimental vaccines that incorporate purified virulence factors and have shown increased protection during challenge. Gene technology has also been used to create a defined, nonreverting mutation in a strain of A. salmonicida, which has enhanced the feasibility of attenuated live vaccines. The development of experimental subunit vaccines against the viral infections and the continued advances in the field of immunostimulants, adjuvants and antigen carriers provide considerable promise for the future development of commercial vaccines for use in salmonid aquaculture.

Animals↗