ASTHMA AND MAST CELL BIOLOGY

Asthma is a chronic inflammatory disease of the lung and its pathophysiology is initiated by mast cell activation in response to the antigen binding to IgE receptor as well as by TH2 cell activation. Mast cells are well established effector cells in asthma where they exacerbate the inflammatory response, playing a key role in early phase, degranulating and increasing histamine. Human mast cells possess high affinity IgE receptors and are ubiquitous but predominantly localized in mucosal and connective tissue and are distributed along blood vessels. There are two types of mast cells: connective tissue mast cells (TC) and mucosal mast cells (T mast cells). TC mast cells contain more heparin, whereas T mast cells contain more chondroitin sulfate. In asthma, mast cell activation can trigger degranulation, releasing secretory granule complex and preformed mediators, such as histamine and proteases, along with the synthesis of leukotrines and prostaglandins, and induction of cytokines and chemokines. Leukotrine inhibitors and omalizumab, which inhibits IgE, both relieve the asthma exacerbation when administered to humans and permit to reduce the use of other drugs. The release of cytokines by mast cells, such as TNF-alpha, IL-1, IL-6 and IL-33, participate in the pathogenesis of asthma. Stress worsens asthma, and this effect is also mediated by mast cell activation through the release of cytokines. Administration of IL-33 in experimental animals provokes pathological effects in the mucosal tissues and augments antibody IgE and IgA in blood vessels. Here, we report the impact of mast cell biology in asthma pathogenesis

Leptospirosis: An important re-emerging infection of animals and man [Λεπτοσπείρωση: Ένα «νεο-αναδυομενο» σημαντικό νόσημα των ζώων και τον ανθρώπου]

Leptospirosis, a re-emerging infection of animals and man, is caused by one of 200 serotypes of Leptospira spp. The genus is currently divided into eight pathogenic species, infecting various animal species and man, either clinically or subclinically.Natural hosts of the microorganism are traditionally, but not exclusively, considered to be rodents. Infected animals excreteLeptospira in the environment, where it may remain for long periods of time, especially if temperatures are about 25°C. The reportedprevalence of infected animals from around the world is between 2% and 46%. In Greece, recent reports show a seropositivityamong abortion cases of small ruminants around 25%, while the relevant percentage among apparently healthy food producinganimals is between 5.7% and 16.2%. The most prevalent serotypes were Bratislava, Australis and Copenhageni, depending on theanimal species. There is a need for more systematic study of the infection in Greece (especially with the possibility of the expectedclimatic changes to result in a temperature rise) © 2017. Journal of the Hellenic Veterinary Medical Society. All Rights Reserved

A cellular model of infection with brucella melitensis in ovine macrophages: Novel insights for intracellular bacterial detection

Intracellular bacteria provoking zoonoses, such as those of the genus Brucella, present a host cell tropism mostly limited to the monocyte/macrophage lineage, leading to chronic inflammatory reactions, difficult-to-eradicate-infections, and widespread prevalence among ruminants. Eradication of brucellosis has been based on programs that translate into a substantial financial burden for both the authorities and stockbreeders, if not strictly followed. To this end, we sought to create an in vitro cell model that could be utilized as future reference for adequately measuring the number of engulfed brucellae/cell, using peripheral blood-derived sheep macrophages infected with B. melitensis at decimal multiplicities of infection (MOI = 5000-5), to simulate the host cell/microorganism interaction and monitor bacterial loads up to 6 days post-infection. We show that the MOI = 5000 leads to high numbers of engulfed bacteria without affecting macrophages’ viability and that the minimum detection limit of our Real-Time PCR assay was 3.97 ± 5.58 brucellae/cell. Moreover, we observed a time-associated, significant gradual reduction in bacterial loads from Day 2 to Day 6 post-infection (p = 0.0013), as part of the natural bactericidal properties of macrophages. Overall, the work presented here constitutes a reliable in vitro cell model of Brucella melitensis for research purposes that can be utilized to adequately measure the number of engulfed brucellae/cell and provides insights towards future utilization of molecular biology-based methods for detection of Brucella. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

Infection of fattening pigs by a virulent strain of Aujeszky's disease virus and its spread in the pig [Προσβολή παχυνόμενων χοίρων από ένα λοιμογόνο στέλεχος του ιοΰ της νόσου Aujeszky και η εξάπλωση του στον οργανισμό]

In this paper, the spread of the virulent 75V19 strain of Aujeszky's disease virus (ADV) in fattening pigs has been examined, and the association of this parameter to the development of relative symptoms has being sought. Four fattening pigs without antibodies against ADV have been oronasally inoculated by instillation of 1075 TCID50 of the infective strain, whilst another four seronegative pigs have been infected by the same dose of the strain administered in aerosol form. The pigs were euthanised at 4 days post inoculation and their tissues were examined by virus isolation and quantification in cell cultures. An extended spread of the virus was seen with both inoculation methods. However, the nasopharyngeal mucosa, the diaphragmatic lobes of the lungs and the pulmonary macrophages were more extensively infected in aerosol inoculated pigs compared to those of the other group. No difference was observed as regards the appearance of clinical disease between the two groups of fattening pigs. The results have also shown that, despite the high replication rate of ADV in the nasal mucosa and its ability to invade the central nervous system of fattening pigs, the degree of its replication in the nervous tissue in these pigs is limited when compared to suckling pigs. © 2018,Journal of the Hellenic Veterinary Medical Society. All Rights Reserved

TRADITIONAL RABBITRIES ON THE ISLAND OF CRETE IN GREECE : GENERAL OUTLOOK

[EN] Greek people consume a limited amount of rabbit meat, with the exception of the island of Crete. In Crete rabbit meat is a traditional dish. A large number of farmer or shepherding families grow rabbits. This study focuses on the traditional rabbitries that serve mainly as a source of meat for the needs of the family, thus become good examples of farming priorities of low-income families. The study focused on rabbitries located at the villages of Krousonas, Sarchos, Korfes and Loutraki in the county of lraklion, Crete. A total of 70 traditional rabbitries were observed for the duration of four months (July to October 2000). The facilities of the rabbitries were of low cost materials, mostly homemade, with the exception of 15 rabbitries, which used commercial cages. The diet of the rabbits was mainly from garden plants supplemented with grains or other kinds of feed materials, such as leftover dry bread. Sorne characteristics of the production-system were: Maximum total rabbits number/farm 22.2±13.0 (n=70); Reproductive does number/farm 3.3±1.3 (n=70); Parturition number/year/doe 7.7±0.8 (n=230); Litter size in birth 8.0± 2.6 (n=105); Litter size in weaning 7.2±2.4 (n=97); Litter size in slaughter 6.5±2.4 (n=95); Slaughter age of fattening (months) 2.8± 0.9 (n=84); Body weight at slaughter 1.7±0.4 (n=84); In respect to health problems, there were not any serious pathological conditions observed other than sorne cases with ear mange lesions (18.7% in reproductive does, 28.6% in reproductive bucks, 15.2% in fryer rabbits) and a small percentage (8%) of slaughtered rabbits were observed with liver abnormalities believed to be due to coccidial infection. At the end of the paper, the different medications in use in the observed farms are refereed. The recommendation and the application mode of the used medications were entirely empiric, thus without a prescription from a veterinarian. In 39 farms no medication was used.[FR] La population grecque consomme peu de viande de lapin sauf sur l'ile de Crete. En Crete, de nombreuses familles de fermier et de bergers élevent des lapins dont la viande est utilisée pour la réalisation d'un plat traditionnel. Ce travail analyse les performances techniques de petits élevages familiaux pratiquant une production vivriere. 11 présente ainsi des exemples intéressants concernant les choix de production réalisés par des familles a bas revenu. Les fermes enquetées étaient localisées dans les villages de Krousonas, Sarchos, Korfes et Loutraki dans le comté d'lraklion en Crete. Au total 70 ateliers cunicoles traditionnels ont été observés durant quatre mois (entre juillet et octobre 2000). L'équipement des clapiers était constitué de matériel peu coOteux, généralement fait maison, a l'exception de 15 élevages équipés de cages commerciales. L'alimentation des lapins provenait principalement de plantes du jardin supplémentées avec des graines ou d'autres produits comme du pain rassis. Les principales caractéristiques techniques du systeme de production étaient les suivantes: Nombre maximum d'animaux/élevage: 22.2±13.0 (n=70); Nombre de femelles reproductrices/élevage: 3.3±1.3 (n=70); Nombre de mises bas/femelle/an: 7.7±0.8 (n=230); Taille des portées a la naissance: 8.0±2.6 (n=105); Taille des portées au sevrage: 7.2±2.4 (n=97); Taille des portées a l'abattage: 6.5±2.4 (n=95); Age a l'abattage (en mois): 2.8±0.9 (n=84); Poids vif a l'abattage: 1.7±0.4 (n=84). Concernant les aspects sanitaires, aucune pathologie grave n'a été observée a l'exception de quelques cas de gale des oreilles (18.7% chez les femelles reproductrices, 28.6% chez les males reproducteurs et 15.2% chez les lapins a l'engraissement). A l'abattage, un faible pourcentage d'animaux (8%) présentaient des anomalies au niveau du foie, probablement dues a une infection coccidienne. Les différents traitements médicamenteux utilisés dans les élevages enquetés sont référencés a la fin de cet article. Généralement, les recommandations et le mode d'utilisation des médicaments étaient totalement empiriques et done réalisés sans prescription vétérinaire. 39 élevages n'utilisaient aucun traitement médicamenteux.Christodoulopoulos, G.; Burriel, A.; Labrinidi, S.; Kritas, S. (2001). TRADITIONAL RABBITRIES ON THE ISLAND OF CRETE IN GREECE : GENERAL OUTLOOK. World Rabbit Science. doi:10.4995/wrs.2001.456SWORD9

Field evaluation of a live vaccine against porcine reproductive and respiratory syndrome in fattening pigs [Εκτίμηση της αποτελεσματικότητας σε επίπεδο εκτροφής ενός ζωντανού εμβολίου κατά του αναπαραγωγικού και αναπνευστικού συνδρόμου του χοίρου σε αναπτυσσόμενους/παχυνόμενους χοίρους]

In this study, a live vaccine based on an European isolate of porcine reproductive and respiratory syndrome (Porcilis PRRS, Intervet) virus has been tested in order to determine the protection of fattening pigs against the respiratory form of the syndrome under field conditions. Ten thousand pigs in an infected farm were vaccinated against PRRS virus at the age of 6 weeks and were compared to non-vaccinated pigs with respect to their health status, mortality, performance parameters (average daily gain, average daily feed intake, feed conversion ratio) and the presence of specific pathogens in their lungs. The results have shown that treated pigs became less frequently sick and have demonstrated reduced mortality compared to untreated ones. As compared to non-vaccinated animals, PRRSvaccinated pigs also performed in a better way with respect to feed conversion ratio (P0.05). Bacteriological examinations of the lungs have revealed increased incidence of respiratory bacterial infection in untreated pigs compared to treated ones. Also a tendency for faster antibody response was detected in the vaccinées. Finally, no clinical side effects were observed after the administration of the vaccine. The results of the present study show that immunization with Porcilis PRRS (Intervet) does protect fattening pigs against the respiratory manifestations of PRRS. © 2018, Journal of the Hellenic Veterinary Medical Society. All Rights Reserved