Postweaning multisystemic wasting syndrome--PMWS. the first year with the disease in Sweden.

Postweaning multisystemic wasting syndrome (PMWS) is causally associated with porcine circovirus type 2 (PCV2) infection of pigs. PCV2 has been present in the Swedish pig population for at least ten years. Despite this, no signs of PMWS were observed in pigs of Sweden until 2003. Since then the disease has spread slowly in Sweden. The pig population of Sweden is geographically isolated, the density of pigs and the pathogen load in the country is low and the trade of animals is organised in a restricted way. To date, there has been little information placed in the peer-reviewed literature on the study of the spread of PMWS in a country during the early phase of the disease outbreak, mainly because diagnosis of PMWS has only occurred after the disease has been recognised on a number of farms. This manuscript documents the studies to date on the PMWS outbreak in Sweden which has been closely monitored since the initial outbreak of diseases on a single farm in 2003 was diagnosed. In Sweden PMWS was officially reported for the first time at a progeny test station during December 2003. One year later sixteen herds have been diagnosed and reported to the authorities: one progeny test station, one nucleus herd, thirteen piglet producers or integrated herds and one specialised fattening herd. Fifteen suspected cases have been deemed negative for PMWS with disease scenarios associated with Lawsonia intracellularis, Brachyspira pilosicoli, Mycoplasma hyopneumoniae, shortcomings in feed composition etc. To date, one year after the index case was reported ten other herds suspected for PMWS are under observation. The PMWS cases are concentrated into the southern part of Sweden. However, the disease is spreading slowly, and in general there are no obvious physical links between affected herds. The data generated to date in Sweden suggest that introduction of a new contagious microbe into the country that is responsible for the PMWS outbreaks appears unlikely, as does the spread of PMWS via semen.

Diarrhoea in the growing pig - a comparison of clinical, morphological and microbial findings between animals from good and poor performance herds.

Diarrhoea among growing pigs (8-13 weeks old) is a significant problem in many herds. Nine herds with poor performance and diarrhoea among growing pigs were selected on the basis of their piglet mean age at a body weight of 25 kg, compared to the overall mean age in Swedish herds. In addition, four herds with good average performance and no problems with diarrhoea were selected. Pigs were necropsied and samples for histology and microbiology were collected. Based on the necropsy findings, the pigs from the good performing herds were all judged to be healthy. The presence of Brachyspira pilosicoli and Lawsonia intracellularis was significantly correlated to poor performing herds and the results indicate that these microbes are main pathogens involved in enteric diseases among Swedish grower pigs. In addition, concomitant infections with other presumptive pathogens were commonly found.

Borna disease in a free-ranging lynx (Lynx lynx).

A free-ranging lynx (Lynx lynx) was shot because of its abnormal behavior. Histopathological examination revealed a nonsuppurative meningoencephalitis. In situ hybridization, immunohistochemistry, and reverse transcriptase PCR analysis showed the presence of Borna disease virus infection in the brain. To our knowledge, this is the first confirmed case of Borna disease in a large felid.

Clinical, radiological and pathological features of 12 Irish setters with canine leucocyte adhesion deficiency.

The clinical, radiological and pathological findings in 12 dogs with canine leucocyte adhesion deficiency (CLAD) from six litters are described. All the dogs were younger than 15 weeks at admission, all had been febrile and 11 had been treated with antibiotics. Seven had been treated for omphalophlebitis. At admission, all had gingivitis, lymph node enlargement and profound neutrophilia. Ten dogs were radiographed and showed various skeletal lesions compatible with metaphyseal osteopathy, craniomandibular osteopathy and osteomyelitis. Four dogs had clinical signs of respiratory distress and seven exhibited a mild interstitial pneumonia at necropsy. Six dogs had skin wounds, with strikingly few neutrophils seen on stained sections. All dogs were euthanased before six months of age due to severe and incurable infections. The clinical signs, radiological features and haematology were strongly suggestive of CLAD. The diagnosis was confirmed by granulocyte function tests and flow cytometry, which revealed impaired adhesion, impaired C3b-mediated phagocytosis and absence of adhesion proteins CD11b/CD18.

Two avian H10 influenza A virus strains with different pathogenicity for mink (Mustela vison).

We compared two strains of avian influenza A viruses of subtype H10 by exposing mink to aerosols of A/mink/Sweden/3,900/84 (H10N4) naturally pathogenic for mink, or A/chicken/Germany/N/49, (H10N7). Lesions in the respiratory tract during the first week after infection were studied and described. Both virus strains caused inflammatory reactions in the lungs and antibody production in exposed mink but only mink/84 virus was reisolated. The lesions caused by mink/84 virus were more severe with higher area density of pneumonia, lower daily weight gain, and more virus in the tissues detected by immunohistochemistry. The results indicate that mink/84 (H10N4), but not chicken/49 virus (H10N7), established multiple cycle replication in infected cells in the mink.

Serum concentrations of thyroid hormones in calves with a transient or persistent infection with bovine viral diarrhoea virus.

Calves persistently infected with bovine viral diarrhoea virus (BVDV) often appear small for their age and it is possible that the virus interferes with their body metabolism by affecting the production of hormones. In this study, the serum concentrations of thyroxine (T4) and triiodothyronine (T3) were measured in calves with transient or persistent BVDV infections. The mean (SD) concentrations of T3 and T4 were lower (P < 0.001) in the persistently infected calves (1.79 [0.67] and 69.2 [23.8] nmol litre-1, respectively) from three dairy herds than in age-matched control calves (2.39 [0.72] and 93.4 [22.1] nmol litre-1, respectively). In each herd, the thyroid hormone levels were also lower in the persistently infected calves than in the controls, the differences being significant (P < 0.05) with the exception of the T3 level in one herd. The girth of the infected calves over the heart was less (P < 0.001) than that of the controls, and, among the infected calves but not among the controls, there was a significant correlation between heart girth and the levels of T3 (r = 0.72, P < 0.001) and T4 (r = 0.60, P < 0.01). Six calves not previously exposed to BVDV were infected through nose-to-nose contact with a persistently infected calf. Their T3 and T4 levels were decreased seven days (P < 0.05 and not significant, respectively) and nine days (P < 0.001 and P < 0.01, respectively) after the infection, when the clinical signs of the disease appeared.

Sweet taste in the calf: III. Behavioral responses to sweeteners.

The hedonic response to the sweeteners acesulfame-K, aspartame, fructose, galactose, glucose, glycine, lactose, maltose, Na-saccharine, sucrose, and xylitol was recorded in five groups of 4-16-week-old calves. The compounds were presented to the calves for 12 or 24 h in two-bottle preference tests with tap water as one choice. Glycine (10 mM and higher), sucrose (20 mM and higher), and fructose concentrations were most preferred. Sodium-saccharine was highly preferred at and above 4 mM concentration, fructose and lactose were preferred above 40 mM, galactose was preferred moderately, acesulfame-K and maltose were preferred inconsistently, and aspartame and xylitol were not preferred at any concentration. The change of preference during the tests was also studied. Three types of consumption changes were observed. 1) Increased preference of the tastant during consumption, seen during sucrose and, to lesser a extent, fructose consumption. 2) Initial high preference for the tastants, diminishing during the test period, observed with fructose, galactose, glucose, glycine, lactose, and maltose. 3) Initial large fluctuations in consumption from the two bottles, but no change in overall preference. This pattern was seen with xylitol and aspartame. This technique seems to offer a method to assess the long-term preference for a compound within one relatively short two-bottle preference session.

Leucocyte adhesion protein deficiency in Irish setter dogs.

Investigation of 12 Irish setter puppies from six litters with severe recurrent infections, neutrophilia and low body weight revealed a leucocyte adhesion protein deficiency with a total lack of CD11b and CD18. Their neutrophil function was severely impaired with a totally absent capacity to ingest C3b-opsonized particles, a significantly impaired capacity to ingest IgG-opsonized particles and significantly diminished adherence to nylon wool when compared with neutrophils from healthy control dogs. The chemiluminescence of patient neutrophils activated by C3b-opsonized particles was, consequently, significantly decreased compared with that of control neutrophils, while the respiratory burst assayed by phorbolmyristate acid (PMA) stimulated nitroblue tetrazolium (NBT)-reduction was normal in the patient group. Random migration and chemotactic responses of patient and control neutrophils, were similar. The etiology, pathogenesis and clinical manifestations of the Irish setter leucocyte adhesion deficiency were similar to that of the leucocyte adhesion deficiency in humans.

The sweet taste in the calf. II. Glossopharyngeal nerve responses to taste stimulation of the tongue.

Recordings were obtained from the glossopharyngeal nerve in 1-5-week-old calves during stimulation of the circumvallate tongue area with NaCl, quinine hydrochloride, citric acid, and the sweet compounds: acesulfam-K, aspartame, fructose, galactose, glucose, glycine, lactose, maltose, monellin, Na-saccharin, sucrose, thaumatin, and xylitol. All compounds except aspartame, monellin and thaumatin gave a nerve response. Glycine, followed by Na-saccharin, elicited the largest responses. Sucrose gave the largest response among the disaccharides, while there was no significant difference between the monosaccharides. Expressed as percent of the NaCl responses, the responses to glycine, sucrose, xylitol, fructose, galactose, glucose, lactose and maltose were considerably larger in the glossopharyngeal nerve than in the chorda tympani nerve. This can be taken as an indication that the posterior region of the tongue serves as the major receptive area for sweet in cattle.

The sweetness-inducing effect of miraculin; behavioural and neurophysiological experiments in the rhesus monkey Macaca mulatta.

1. The gustatory effects of miraculin, the sweetness-inducing protein from the miracle fruit Synsepalum dulcificum, was studied in the rhesus monkey, Macaca mulatta.2. The intake of five acids was recorded in two-bottle preference tests, one bottle containing acid and the other tap water, before and after miraculin treatment. All the acids tasted more pleasant after miraculin.3. The electrical activity of the chorda tympani nerve to stimulation of the tongue with a variety of sweeteners, acids, sodium chloride and quinine hydrochloride was recorded in anaesthetized animals.4. Pre-treatment of the tongue with 0.3-5 mg miraculin doubled the summated nerve response to the acids and diminished the response to sucrose by about 10%. The enhancement lasted for at least an hour and the diminution up to 20 min.5. After miraculin treatment the Spearman's rank correlation coefficient between the order of increased intake of acids and the order of enhancement of the summated nerve response was 0.99.6. A solution of 0.1 mg miraculin per ml. elicited a weak nerve response. No preference over water for this concentration of miraculin was recorded in the two-bottle tests.7. The activity of twenty-nine single taste fibres, selected for their responsiveness to sweetness or acids or both, was recorded after miraculin treatment. Effects were obtained in nine fibres which were similar but more pronounced than those observed in the summated recordings. Before miraculin, these fibres responded better and to a larger variety of sweeteners (81%) than the other fibres (40%). After miraculin, acids elicited on the average 2.3 times more activity than before, while the response to sweeteners was depressed. In twenty fibres no effect of miraculin was observed. These fibres responded to fewer of the sweeteners and were more stimulated by the non-sweet stimuli than the first group.8. The results suggest that miraculin acts on those structures in the taste cell membrane that are involved in perception of the sweet taste, making them sensitive to acids. The new quality of sweetness after miraculin treatment is signalled by taste fibres which normally respond to sweet substances but which, under the influence of miraculin, are responding to acids. It is likely that the quality of a taste stimulus is conveyed by the identity of the taste fibres.

Prostaglandin-induced parturition in swine -- a field study on its accuracy after treatment with different amounts of PGF.

This trial was performed within one large piglet producing herd in Sweden during June-August 1976. One hundred and sixty sows were randomly assigned to one of the following treatments: (1) 15 mg PGF2alpha i.m., (2) 20 mg PGF2alpha i.m., (3) two injections of 10 mg PGF2alpha i.m. at c. 8 h interval, (4) untreated countrol sows. PGF2alpha was administered in the morning of days 111, 112 or 113 of pregnancy. Of the PGF2alpha-treated sows, 83--85% farrowed within 48 h after treatment. No effect of day of treatment was found. Nor was any difference between groups observed. Neither of the treatments had a significantly negative influence of the viability of the piglets born. A numerically lower incidence of agalactia post partum was demonstrated in sows treated once with 15 mg or 20 mg PGF2alpha. A possible effect of PGF2alpha for prevention of agalactia post partum is discussed.