Disposition of 14C-sarafloxacin in Atlantic salmon Salmo salar, rainbow trout Oncorhynchus mykiss. cod Gadus morhua and turbot Scophthalmus maximus, as demonstrated by means of whole-body autoradiography and liquid scintillation counting

113

This review summarises the state of knowledge of both viral and bacterial diseases of Atlantic cod Gadus morhua, and their diagnosis, prophylaxis and treatment. The most important losses have been at the larval and juvenile stages, and vibriosis has long been the most important bacterial disease in cod, with Listonella (Vibrio) anguillarum dominant among pathogenic isolates. Vaccination of cod against pathogens such as L. anguillarum and Aeromonas salmonicida clearly demonstrates that the cod immune system possesses an effective memory and appropriate mechanisms sufficient for protection, at least against some diseases. Well-known viruses such as the nodavirus that causes viral encephalopathy and retinopathy (VER), infectious pancreatic necrosis virus (IPNV) and viral haemorrhagic septicaemia virus (VHSV) have been isolated from Atlantic cod and can be a potential problem under intensive rearing conditions. No commercial vaccines against nodavirus are currently available, whereas vaccines against IPNV infections based upon inactivated virus as well as IPNV recombinant antigens are available. A number of investigations of the pharmacokinetic properties of antibacterial agents in cod and their efficacy in treating bacterial infections have been reviewed.

Section: Pharmacokineticsmentioning

confidence: 99%

Viral and bacterial diseases of Atlantic cod Gadus morhua, their prophylaxis and treatment: a review

Samuelsen¹,

Nerland²,

Jørgensen³

et al. 2006

113

Section: Pharmacokineticsmentioning

confidence: 99%

“…Furthermore, in fish species destined for human food species, the establishment of correct withdrawal times is based on knowledge of the elimination rate of the drugs from tissues. As the pharmacokinetic properties of antibacterial agents may vary significantly from species to species, the disposition of a drug should be investigated in the particular 67 Dis Aquat Org 48: [57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74] 2001 species in which it is intended to be used (Kleinow et al 1994, Martinsen et al 1994, van der Heiden 1994.The range of antibacterial agents available to fish farmers is limited. At present, 6 antibacterial agents are used in aquaculture in Norway; the quinolones flumequine and oxolinic acid, the tetracycline derivative oxytetracycline, the potentiated sulphonamide Tribrissen (trimetoprim + sulphadiazine) and florfenicol which is an amphenicol derivative.…”

mentioning

confidence: 99%

Diseases, prophylaxis and treatment of the Atlantic halibut Hippoglossus hippoglossus: a review

Bergh

Nilsen²,

Samuelsen³

2001

After substantial investments in research, the Atlantic halibut Hippoglossus hippoglossus is now being cultivated commercially in Norway, Iceland, Scotland and Canada. As with other domesticated species, disease problems have been experienced. This review summarizes the current state of knowledge of diseases of the Atlantic halibut, and their diagnosis, prophylaxis and treatment. In economic terms, the most important losses have been suffered at the larval and juvenile stages. The most important infections are caused by nodaviruses, causative agents of Viral Encephalopathy and Retinopathy (VER), which are the major reason why Norway's production of halibut fry has been level since 1995. An aquatic birnavirus, Infectious Pancreatic Necrosis Virus, is also an important agent of mortality. Vibrio anguillarum, Flexibacter ovolyticus and atypical Aeromonas salmonicida are the major bacterial pathogens. The protozoan parasites recorded include Ichthyobodo sp., the microsporidium Enterocytozoon sp., Trichodina hippoglossi, and the metazoan pathogens include myxozoans, helminths, Entobdella hippoglossi, Lepeophtheirus hippoglossi and other parasitic copepods. Experimental vaccines have been tested against V. anguillarum and atypical A. salmonicida, with good results. A recombinant vaccine against nodaviruses is under development. A few trials have been carried out on non-specific immunostimulants, but no such treatment is currently available. A number of efficacy and pharmacokinetic trials with various antibacterial agents have also been published. KEY WORDS: Atlantic halibut · Diseases · Prophylaxis · Treatment Resale or republication not permitted without written consent of the publisherDis Aquat Org 48: [57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74] 2001 unknown may accidentally compromise the defence systems of the host. Thirdly, disease conditions that may be common among wild fish are largely unrecognised by humans. However, in aquaculture systems the fish farmer will recognise signs of disease such as reduced growth, abnormal behaviour and increased mortality, all of which rapidly call for attention by veterinarians and scientists.The main challenge experienced by halibut farms has been to achieve adequate survival rates, particularly during the early life stages. Thus, since the early 1990s, the amount of experience and knowledge of diseases of viral, bacterial or parasitical etiology of the Atlantic halibut has grown significantly. The evidence for the importance of diseases that affect the early life stages, such as infections by birnaviruses (Biering et al. 1994), nodaviruses (Grotmol et al. 1995(Grotmol et al. , 1997, or various opportunistic bacteria (Bergh et al. 1992b) has now been demonstrated by different challenge experiments (Table 1).The parasite fauna of wild Atlantic halibut have not been widely studied, for which reason our knowledge of potential harmful parasites in farmed fish is limited. Studies of parasites on wild halibut have mainly concentrated on desc...

“…To establish correct dosage regimes and thereby promote optimal use of a drug, data derived from pharmacokinetic investigations and knowledge of the pathogen's susceptibility to the drug in use is essential. Since the pharmacokinetic properties of antibacterial agents vary between species, drugs should be investigated in the species in which they are intended to be used (Kleinow et al 1994, Martinsen et al 1994, van der Heiden et al 1994. In cod, available pharmacokinetic data is limited to studies by Hansen & Horsberg (2000 ) and Samuelsen et al (2003), where the pharmacokinetic properties of the quinolones flumequine and oxolinic acid, respectively, were examined following intravenous injection (i.v.…”

Section: Introductionmentioning

confidence: 99%

Pharmacokinetics of florfenicol in cod Gadus morhua and in vitro antibacterial activity against Vibrio anguillarum

Samuelsen¹,

Bergh²,

Ervik³

2003

The pharmacokinetic profile of the antibacterial agent florfenicol was studied in plasma after intravenous (i.v.) injection and in plasma, muscle and liver following oral (p.o.) administration to cod Gadus morhua, held in seawater at 8°C and weighing 100 to 200 g. Following i.v. injection, the plasma drug concentration-time profile showed 2 distinct phases. The plasma distribution half-life (t 1/2 α) was estimated to be 1.6 h, the elimination half-life (t 1/2 β) to be 43 h, the total body clearance (Cl T ) to be 0.015 l kg -1 h -1 and mean residence time (MRT) to be 74 h. The volume of distribution at steady state, V d(ss) , was calculated to be 1.1 l kg -1 . Following p.o. administration, the bioavailability was estimated to be 91%, the peak plasma concentrations (C max ) to be 10.8 µg ml -1 and the time to peak plasma concentrations (T max ) to be 7 h. Corresponding C max and T max values were 13.0 µg g -1 and 9 h, respectively, in muscle and 12.1 µg g -1 and 9 h, respectively, in liver. The in vitro minimum inhibitory concentration (MIC) values of florfenicol against 3 Vibrio anguillarum strains isolated from diseased cod (A-21, HI-610, HI-618) were 0.5 µg ml -1 for all 3 strains. KEY WORDS: Fish · Pharmacokinetics · Florfenicol Resale or republication not permitted without written consent of the publisherDis Aquat Org 56: [127][128][129][130][131][132][133] 2003 field situation (J. P. Pedersen pers. comm.). After 5 d of treatment daily mortality decreased only slowly and, for this reason, florfenicol was replaced by flumequine, with good results. The in vitro minimum inhibitory concentration (MIC) value for the presumed pathogen against florfenicol was found to be 0.5 µg ml -1. This study was therefore initiated to examine the pharmacokinetic properties of florfenicol in cod, relate the data to the MIC values of bacterial strains isolated from diseased cod and other fish pathogenic bacteria, and evaluate the need for adjustment of the dosage regime. The drug was administered by i.v. injection and incorporated in feed for p.o. administration. MATERIALS AND METHODSChemicals. The Directorate of Fisheries, Department of Quality Control (Bergen, Norway) supplied florfenicol and florfenicol amine standards. Thiamphenicol was obtained from Sigma Chemical and metomidate from Norsk Medisinaldepot. 1-Heptane sulphonic acid was from Fluka Chemie, whereas acetonitrile, methanol (high performance liquid chromatography [HPLC]-grade), phosphoric acid (H 3 PO 4 ), disodium hydrogen phosphate (Na 2 HPO 4 ), trisodiumphosphate (Na 3 PO 4 ), 5-sulphosalicylic acid, hydrochloric acid (HCl), tris(hydroxymethyl)-aminomethan (TRIS), triethylamine and potassium hydroxide (KOH) (p.a.-grade) were all from Merck. Solid phase extraction columns (SPE) (Bond Elute C-18, 100 mg, 1 ml) were from Varian. Stock solutions of florfenicol, florfenicol amine and thiamphenicol were prepared at a concentration of 0.1 mg ml -1 in methanol and stored at -20°C. Working standards were prepared by dilution from the stock solutions with met...