Placebo-induced changes in FMRI in the anticipation and experience of pain

The experience of pain arises from both physiological and psychological factors, including one's beliefs and expectations. Thus, placebo treatments that have no intrinsic pharmacological effects may produce analgesia by altering expectations. However, controversy exists regarding whether placebos alter sensory pain transmission, pain affect, or simply produce compliance with the suggestions of investigators. In two functional magnetic resonance imaging (fMRI) experiments, we found that placebo analgesia was related to decreased brain activity in pain-sensitive brain regions, including the thalamus, insula, and anterior cingulate cortex, and was associated with increased activity during anticipation of pain in the prefrontal cortex, providing evidence that placebos alter the experience of pain.     

The River Bjerkreim in SW Norway - Successful Chemical and Biological Recovery after Liming

On a large scale, the acidified River Bjerkreim, southwestern Norway, has been treated with lime since the autumn 1996. During the Atlantic salmon (Salmon salar) smolting period pH has been above 6.2 and LAl concentrations below 10 µg L-l. Before 1996, only the western part of the watercourse harboured acid-sensitive species, such as the Atlantic salmon, snails, mayflies, daphnids and Gammarus lacustris. Prior to liming in 1996, Atlantic salmon fry (0+) and parr (≥1+) were found in 4 of 20 sampling sites, contrary to 17 (fry) and 12 (parr) in 1999. Atlantic salmon catches have increased from about 0.8 tons in 1994 to about 10 tons in 1998 and 1999. Acid-sensitive invertebrates have invaded the limed parts of the river.     

Anesthesia during Vaccination of Atlantic Salmon: Compliance with Recommended Procedures

The preparation and use of two anesthetic agents for fish, a buffered metacaine solution for anesthesia in connection with vaccination procedure, and an available benzocaine solution for minor procedures, were studied at a commercial fish farm producing Atlantic salmon, Salmo salar L., smolts. The procedures were compared with the given recommendations to evaluate compliance with recommended procedures and labels. The personnel were evaluated to be non‐compliant with labels and procedures for both anesthetic agents used and the recommended exposure time in the baths. Five important themes were identified: the preparation and use of the anesthetics, fish welfare, training procedures, and occupational hazard aspects. One important reason for non‐compliance was that the rate of delivery of anesthetized fish to the vaccination table was more dependent on the speed of vaccination, and less on the anesthetic depth of the fish. This may be a management issue. Management decisions may create an environment leading to situations where errors are more likely to occur. Better communication between the fish health‐service team and the personnel, more tailored procedures, and a preprepared anesthetic agent might increase compliance with procedures and may promote fish welfare and welfare of the employees.     

Analysis of bacterial diversity in the intestine of grass carp (Ctenopharyngodon idellus) based on 16S rDNA gene sequences

In the current study, we assessed bacterial diversity in the gut content of pond-reared grass carp (Ctenopharyngodon idellus), in the associated habitat environments (pond water and sediment) and in the ingested food (commercial feed and the reed Phragmites australis) by analysing 16S rDNA sequences from clone libraries. The highest bacterial diversity was observed in the gut content and was determined by the total number of operational taxonomic units, Shannon diversity index (H), Shannon equitability index (E_H), Coverage (C_good) and rarefaction curves calculated from the 16S rDNA gene libraries. Our data indicated that allochthonous gut microbes of grass carp were distinctively different from the corresponding environmental microbes. The pairwise similarity coefficient (C_s) for microbe communities between gut content and ingested food was higher than for those between the gut content and habitats, indicating that the allochthonous microbiota identified in the intestines of grass carp were phylogenetically closer to those in the ingested food than to those in the habitat. Based on our study and previous research, we suggest that the digesta of grass carp harbours a microbiota phylogenetic core of Proteobacteria and Firmicutes and this observation deserves further investigations with respect to a potential pool of probiotics to grass carp.     

Type C botulism in dairy cattle from feed contaminated with a dead cat.

Four hundred twenty-seven of 441 adult Holstein dairy cattle from a 1,200-cow dairy died over a 1-week period during early spring 1998. Affected animals were from 4 late lactation pens, one of which included the bull string. Signs included weakness, recumbency, watery diarrhea, and death. Eighty animals from the 4 pens were dead approximately 8 hours after the first ill cows were noted. Affected cows would collapse on stimulation and extend all 4 limbs with moderate rigidity. Several lacked lingual tonus and had abdominal breathing patterns. The animals had been fed a load of total mixed ration that included a rotten bale of oat hay containing a dead cat. No common toxicants were identified, and pathologic examination revealed no consistent lesions. Testing of tissue from the cat carcass found in the feed sample using mouse protection bioassay identified the presence of type C botulinum toxin. Samples of feed, tissue from affected animals, cat tissue from feed, milk, and serum were also tested using an enzyme-linked immunosorbent assay (ELISA) specific for type C botulinum. Two samples of rumen contents were tested and found to be positive for botulism by ELISA, and 1 of 3 liver samples had a weak positive finding. No botulinum toxin was found in milk or sera using the ELISA.     

Pharmacokinetics and pharmacodynamic effects of meloxicam in piglets subjected to a kaolin inflammation model

The pharmacokinetics and the analgesic, anti-inflammatory and antipyretic effects of meloxicam were investigated in a placebo controlled study in 2-week-old piglets. Inflammation was induced by a subcutaneous injection of kaolin in the left metacarpus, and 16 h later, meloxicam (0.6 mg/kg) or saline was administered intramuscularly. The absorption half-life was relatively short (0.19 h) and the elimination half-life was 2.6 h. Mechanical nociceptive threshold testing was used to evaluate the analgesic effect, but no significant effect of the meloxicam treatment was found. The skin temperature of the inflamed area increased after the kaolin injection, but no significant decrease in temperature was found after administration of meloxicam. Only limited pyresis was observed after the kaolin injection, and no significant antipyretic effect of meloxicam was found. The results indicated that this dose of meloxicam had very limited anti-inflammatory and analgesic effects in piglets.     

Development and intercalibration of methods in nordic freshwater fish monitoring

The awareness of the effects of transboundary pollution has increased the necessity to use comparable methods and to initiate joint studies between countries in environmental monitoring. In freshwater fish monitoring a number of different methods have been used, strongly reducing the possibilities to comparative assessments between countries. In 1990, a workshop on freshwater fish sampling was initiated in order to develop and intercalibrate methods used in freshwater fish studies in the Nordic countries. During a three year period, a new type of multi-mesh gillnet to be used for fish monitoring in Norway, Finland and Sweden have been developed. Comparative studies and gillnet-selectivity assessments show that these new multi-mesh gillnets better describe the actual population structure of European perch (Perca fluviatilis), roach (Rutilus rutilus) and Arctic char (Salvelinus alpinus) than do the traditional gillnet series used in the Nordic countries. Ageing of fish is central in most environmental studies, however, the comparability of analyses performed at different laboratories may be low. Comparative age analyses between the three countries have been performed for a number of fish species. The results of ageing E. perch, whitefish (Coregonus sp.) and roach indicate that differences between laboratories can be reduced by intercalibration. In the future, the workgroup will be focused on a further development of joint methods within studies of freshwater fish and on joint intemordic assessments on species distribution, abundance and life history characteristics in relation to airborne pollutants and liming.     

An age-dependent association between a leptin C3469T single nucleotide polymorphism and intramuscular fat content in pigs

The objective of this work was to investigate whether the C3469T mutation at exon 3 of the pig leptin (Lep) gene is associated with fatness and if the magnitude and direction of these associations is consistent within age. Repeated measurements on body weight (BW), ultrasonic subcutaneous backfat (SB) and loin-muscle (LT) thickness, and intramuscular fat (IMF) content and composition were taken at 160, 180, 215 and 225 days of age on 162 Duroc barrows previously genotyped for the C3469T mutation. Plasma leptin concentration was determined at 180 days. A total of 505 records of IMF content and composition, which were determined both in live samples of longisimus dorsi muscle (LM) and in carcass samples of LM and gluteus medius muscle, were used in the analyses. The genotypic frequencies associated with the C3469T Lep mutation were 0.76, 0.23, and 0.01 for TT, TC, and CC genotypes, respectively. The effect of the Lep genotypes was assessed using a Bayesian approach based on a polynomial mixed model on age. No evidence was found for an association of the Lep genotypes neither with BW, SB thickness nor with plasma leptin concentration. The posterior mean of the difference TT–TC ranged, for LT, from 0.82 (160 days, posterior probability density (PP)> 0 of 87%) to 1.98 mm (220 days, PP > 0 of 96%) and, for IMF, from 0.96 (160 days, PP > 0 of 84%) to − 1.64 mg/g DM (220 days, PP > 0 of 2%). The results suggest an age-dependent association of the C3469T Lep polymorphism with LT and IMF, which may be useful to explain some controversial results in the literature concerning the association of this polymorphism with IMF content.     

Dirofilaria repens infection in a dog imported to Norway

Dirofilaria repens infection was diagnosed in a dog that had been imported to Norway from Hungary three years previously. The dog was a four-year-old castrated male mixed-breed dog and presented for examination of two masses on the right thoracic wall. Fine needle sampling from the subcutaneous nodules and subsequent cytological examination revealed a high number of microfilariae and a pyogranulomatous inflammation. At re-examination approximately 3 weeks later, both masses had apparently disappeared spontaneously, based on both inspection and palpation. However, examination of peripheral blood by a modified Knott’s test revealed a high number of unsheathed microfilariae with mean length of 360 μm and mean width of 6-7 μm, often with the classic umbrella handle appearance of D. repens. Polymerase chain reaction and sequencing confirmed the D. repens diagnosis. Subcutaneous dirofilariosis caused by D. repens is probably the most common cause of human zoonotic dirofilariosis in Europe, but currently is rarely encountered in northern countries such as Norway. However, travelling, import and relocation of dogs have increased, and thus the geographical range of these parasites is likely to increase from traditionally endemic southern regions. Increasing numbers of autochthonous cases of D. repens infections in dogs have been reported in eastern and central Europe. Although infection with D. repens often induces only mild signs or subclinical infections in dogs, they nevertheless represent a reservoir for zoonotic transmission and thus a public health concern, and, in addition, due to the long prepatent period and the high frequency of subclinical infections or infections with unspecific clinical signs, could easily be missed. Lack of experience and expectation of these parasites may mean that infection is underdiagnosed in veterinary clinics in northern countries. Also, predicted climate changes suggest that conditions in some countries where this infection is currently not endemic are likely to become more suitable for development in the intermediate host, and thus the establishment of the infection in new areas.     

Effects of temperature and dietary n-3 and n-6 fatty acids on endocytic processes in isolated rainbow trout (Oncorhynchus mykiss,Walbaum) hepatocytes

Effects of different incubation temperatures (2, 8, 14 and 20°C) and hepatocyte membrane fatty acid composition on the rate of internalization and lysosomal degradation of the ligand, mannosylated albumin, that is taken up by receptor-mediated endocytosis, were investigated in rainbow trout (Oncorhynchus mykiss, Walbaum). The fish were kept at a water temperature ranging from 9 to 14°C and fed pelleted diets coated with either capelin oil (control), EPA/DHA-concentrate (rich in n-3 polyunsaturated fatty acids) or soybean oil (rich in n-6 unsaturated fatty acids) for at least 3 months prior to sampling. The endocytic uptake mediated by the mannose receptor was very efficient at all temperatures studied. Lysosomal degradation, on the other hand, came to a halt below 8°C. The activation energies for uptake and degradation were 54.6 and 164.2 kJ/mol respectively. No negative effects of increased amounts of either n-3 or n-6 fatty acids were observed on the endocytic parameters studied. On the contrary, multivariate analysis indicated a positive relationship between high levels of n-6 fatty acids and low unsaturation index in the phosphatidylcholine (PC) fraction of the hepatocytes and the internalization rate of 2°C, meaning that the rate of receptor-mediated endocytosis may be affected by membrane fatty acid composition.