Contents page of the issue March 2008




EQUINE
B. Tóth, N. M. Slovis, M. L. Frazer, B. G. Bentz, K. C. MacGillivray, N. Nógrádi: Lawsonia intracellularis infection in horses. Literature review and case report / 131

PORCINE
O. Biró, L. Ózsvári, Z. Lakner: The relationship between veterinary management and performance of Hungarian pig farms – a methodological experiment and its conclusions / 138

POULTRY
Cs. Nemes, D. Szalay, K. Ursu, V. Palya, R. Glávits: Turkey coranavirus enteritis in Hungary. Part 2. Own observations / 148
A. Győrffy, Zs. Rónai, Sz. Áprily, A. Zsarnovszky, L. V. Frenyó, F. Bogenfürst, P. Rudas, T. Bartha: Metabolic and hormonal aspects of fatty liver production in liver- and meat-type goose hybrids / 156

VIROLOGY
Zs. Szeleczky, S. Kecskeméti, I. Kiss, B. Lomniczi: Genetic analysis of old Hungarian avian influenza viruses / 165

SMALL ANIMALS
R. Wissler: Pathogenesis and therapy of osteoarthritis in the human and veterinary medicine / 180
B. Kohn: Immune-mediated haemolytic anaemia in cats / 183

LETTER TO THE EDITOR
Weather – environment – wild animal health (I. Csapó) / 186

JUBILEE
Scientific meeting for the 120th anniversary of Sándor Kotlán, academician’s birth and 40th anniversary of his death (R. Farkas) / 188

EVENT
National Veterinary Day (Budapest, 11 December 2007) / 190

BOOK REVIEW
K. Fodor: What should my dog eat? Proper feeding of our pets (L. Visnyei) / 179

B. Tóth – N. M. Slovis – M. L. Frazer – B. G. Bentz – K. C. MacGillivray – N. Nógrádi:
LAWSONIA INTRACELLULARIS INFECTION IN HORSES. LITERATURE REVIEW AND CASE REPORT

The authors summarize the etiology, pathogenesis, symptoms and therapy of proliferative enteropathy caused by Lawsonia intracellularis. Characteristic clinical signs of the disease are: ventral and submandibular oedema, thickening of the intestinal wall, hypoproteinaemia. The causative agent can be detected by serology. For the treatment those antibiotics should be used which may reach high intracellular concentration. In the second part of the article the authors present the case of a 6 month old thoroughbred filly with proliferative enteropathy further complicated with pneumonia and enteral salmonellosis.

O. Biró – L. Ózsvári – Z. Lakner:
THE RELATIONSHIP BETWEEN VETERINARY MANAGEMENT AND PERFORMANCE OF HUNGARIAN PIG FARMS – A METHODOLOGICAL EXPERIMENT AND CONCLUSIONS

The article demonstrates and quantifies the stochastic interrelationships between breeding technology, housing conditions of pig-producing units, herd health management, farm management strategy and performance of pig production. Performance is defined in a broad sense, reflecting the complexity of pig production, taking into consideration technological and economic indices. According to the hypothesis of researchers, there is statistically significant relationship between the above factors and the performance of a pig farm. Structural equation modelling was carried out to test this hypothesis. Data for analysis have been acquired by a direct-question survey of 120 Hungarian pig-breeding farms in 2004. The fitness of structural equation model to system characterising interrelationships between different factors, such as management strategy, herd health management, housing construction, breeding technology and performance of pig-production has resulted in a statistically significant solution. It means that the system of equations is able to characterize the interrelations between the examined factors. Results of the survey highlight the great impact of management strategy and herd health management on the performance of farms. The correlation with the same level of significance could be proven between herd health management, housing construction and epidemiological situation.

Cs. Nemes – D. Szalay – K. Ursu – V. Palya – R. Glávits:
TURKEY CORANAVIRUS ENTERITIS IN HUNGARY. PART 2. OWN OBSERVATIONS

The authors report on the occurrence of turkey coronavirus enteritis in Hungary and the outcomes of their own research.
The disease was observed in 13 turkey flocks. The disease and the mortality started in one-two weeks of age and continued in the following six-seven weeks in three flocks. Mortality in these flocks was relatively high (> 35%). In the first period of the disease acute enteritis, indigestion (foamy-watery cecal-contents), dehydration, starvation were found in the dead birds. Histological examination showed degeneration and necrosis of enterocytes of the villi, and depletion and necrosis of lymphocytes of bursa Fabricii. After the third week of the disease secondary bacterial (E. coli, Salmonella spp.) sepsis represented the main cause of death, presumably as a result of immunosuppression. In this period of the disease uneven growth and weight gain was typical to these flocks.
In the flocks affected by the disease after the age of five weeks diarrhoe and immunosuppression were observed, though the mortality proved to be of a lower rate (> 1.5%) and histological findings were less serious. Growth retardation caused considerable economic loss in these flocks, as well.
The diagnosis was performed on the basis of epidemiological data, as well as on the symptoms and – besides molecular diagnostics of turkey coronovirus – the assessment of pathological and histological findings.

A. Győrffy – Zs. Rónai – Sz. Áprily – A. Zsarnovszky – L. V. Frenyó – F. Bogenfürst – P. Rudas – T. Bartha:
METABOLIC AND HORMONAL ASPECTS OF FATTY LIVER PRODUCTION IN LIVER- AND MEAT-TYPE GOOSE HYBRIDS

For thousands of years, fatty liver (foie gras) produced by force-feeding has had considerable importance in gastronomy. However, as a result of increasingly stringent animal welfare regulations and consumers’ expectations, the classical methods of fatty liver production will likely be replaced by new technologies. As a consequence of the new animal welfare regulations, it can be anticipated that these new technologies will increasingly be based on the optimalization of the natural, physiological processes rather than the use of various feed additives or invasive feeding methods. Therefore, it is essential to understand the physiological regulatory mechanisms that influence fatty liver production. Efficiency of fatty liver production and the level of voluntary feed intake, that may partially or totally substitute force feeding are determined by the genetic and hormonal differences between the different breeds and individuals. From the several known metabolic factors the authors focused hereon thyroid hormones. Experiments were carried out on liver- and meat-type end-product goose hybrids. Animals were raised from day 1. They applied pregavage between week 8 and 10, then the animals were force-fed from week 11 for 18 days. Experimental animals were allotted into groups based on the following criteria: their type (liver or meat), gender, appetite, weight gain, and on the timing of feed intake to determine which of the preceding factors have significant impact on fatty liver production. The authors measured body weight, liver weight, and plasma thyroid hormone concentrations of each individuals in each group. They found that besides the age and type, liver weight is also determined by the appetite of the given individual. Correlated thyroid hormone measurements showed increased plasma levels of the active hormone, triiodothyronine (T3). High T3 concentration has been reported to increase appetite, thereby explaining the aforementioned correlation between increased appetite and liver growth.

Zs. Szeleczky – S. Kecskeméti – I. Kiss – B. Lomniczi:
GENETIC ANALYSIS OF OLD HUNGARIAN AVIAN INFLUENZA VIRUSES

Certain genes of 13 avian influenza viruses (AIV) isolated in the 1970s were subjected to phylogenetic analysis. The viruses derived from the eastern part of Hungary from ducks and guinea fowls with relatively severe respiratory signs. In addition to the hemagglutinin (HA) subtypes (H4, H5, H6, H7 and H10) identified at the time by serological methods, neuraminidase (NA) subtypes have been identified with genetic analysis. Based on the amino acid pattern at the proteolytic cleavage site of the HA, it was ascertained that all H5 and H7 strains belonged to the low pathogenicity (LP) category. Phylogenetic analysis of the HA, NA and NS genes allowed the following epidemiological conclusions to be drawn. (1) All Hungarian strains belonged to the Eurasian lineage of AIV. (2) H5 strains were the members of an old European group. The H4 strains originated from three different sources (two from the Far East while one from Europe). (3) The fact that most viruses in H4 and H5 subtypes were reassortants (some even multiple ones; Figure 3) suggested that their reservoirs were unlikely to be wild aquatic birds but rather domestic ducks. Further studies of old viruses would be needed for a more detailed knowledge on the role of these „artificial” reservoirs in the maintenance and epidemiology of AIV.