Genetic Diversity of Pasteurella dagmatis as Assessed by Analysis of the 16S rRNA and rpoB Gene Sequences

A total of 16 Pasteurella dagmatis strains, including 11 feline and 4 canine isolates as well as one strain isolated from a tiger, were analyzed using partial 16S rRNA and rpoB gene sequence comparison. Phylogenetic studies based on both genes revealed that the population of P. dagmatis recovered from cats in Poland differs markedly from canine strains, constituting a well-separated cluster within Pasteurella sensu stricto species group. The isolate from a tiger seems to represent yet another evolutionary lineage within P. dagmatis

Humoral and Cellular Response of Pheasants Vaccinated against Newcastle Disease and Haemorrhagic Enteritis

The purpose of the experiment was to define whether and to what extent can prophylactic vaccinations against Newcastle disease (ND) and haemorrhagic enteritis (HE) affect the humoral and cellular response in pheasants. The evaluation of humoral response was performed on a basis of agglutinin titre after administered antigen and the cellular immunity index was the delayed type hypersensitivity (DTH) reaction. The pheasants were prophylactically vaccinated against Newcastle Disease (ND) on the 1st, 28th and 56th day of life. Moreover, on the 49th day of life, part of the birds was given in the drinking water a vaccine containing the HEV (Haemorrhagic Enteritis Virus). Fourteen days after the HEV vaccination, the birds were intravenously given 0.5 ml of the 10% SRBC (sheep red blood cells) suspension. Simultaneously with the SRBC administration the delayed hypersensitivity test was performed by intradermal administration of phytohaemagglutinin (PHA). It was shown that in pheasants vaccinated with NDV and additionally with HEV, the specific agglutinin anti-SRBC titre was significantly (p < 0.05) lower than in birds vaccinated against ND only. It also appeared that, the antibodies resistant to 2-mercaptoethanol were 43% of the total pool of specific anti-SRBC antibodies in the NDV vaccinated birds, whereas in birds vaccinated also with HEV they were 75%. No significant differences were found in the DTH test. Only in the HEV vaccinated pheasants the tendency to increase the wing index value was noted. The results confirm the observations concerning immunosuppressive effects of simultaneous vaccinations. They also indicate that overloading the pheasants with many antigens (ND and HEV vaccination) may weaken the humoral response to administered SRBC

Encapsulation of lactobacillus casei into calcium pectinate-chitosan beads for enteric delivery

Gel beads were prepared by extrusion of various types of pectin into 0.15 M calcium chloride. Size, morphology, and textural properties of 3 types of beads were evaluated and it was established that the use of 3 w/v % amidated pectin provides the optimal characteristics suitable for encapsulation of live bacteria. Lactobacillus casei NCIMB 30185 (PXN37) was encapsulated into calcium pectinate gel through the extrusion of a live bacteria dispersion in 3 w/v % pectin into a solution of calcium chloride. The capsules were then additionally coated with chitosan. The viability of bacteria within these capsules was studied under model gastrointestinal conditions in vitro (simulated gastric and intestinal juices). It was established that pectin-chitosan capsules can provide protection to L. casei from the gastric acid and result in high levels of viable bacteria released in the intestine

Development of bioadhesive microparticles for vaginal use of probiotics

Lors d’infections vaginales, divers pathogènes se développent au détriment de la flore locale. L’utilisation de lactobacilles en traitement prophylactique et/ou curatif pourrait pallier ce problème. Le but de ce travail de thèse a été de développer des microparticules mucoadhésives à base de pectine et d’acide hyaluronique (HA) pour la libération intravaginale de probiotiques. Quatre souches probiotiques ont été associées à des prébiotiques afin d’obtenir un effet symbiotique. Les microparticules ont été formulées par émulsification-gélification ionique. Dans un premier temps, l’étude de l’influence de différents paramètres de procédé et de formulation a permis de définir les conditions opératoires pour l’obtention de microparticules d'environ 140 µm de diamètre encapsulant des probiotiques viables. Puis, les propriétés mucoadhésives des microparticules ont été évaluées in-vitro et ex-vivo par des mesures rhéologiques en mode dynamique et par des tests d’indentation. La présence d’HA entraine une augmentation importante du pouvoir bioadhésif des particules. Enfin, ces microparticules ont été incorporées dans des comprimés par un procédé de granulation humide. L’encapsulation des bactéries permet leur protection lors du procédé de compression. De plus, contrairement aux formes classiques d'administration des probiotiques, les microparticules permettent d'obtenir un profil de libération prolongée des bactéries sur environ 10h contre 1h dans le cas d’un comprimé comportant des probiotiques non encapsulés. Un début de prolifération bactérienne s’opère entre 16 et 24 heures. Le comprimé ainsi développé est tout-à-fait adapté à une application vaginaleMore than 300 millions of women around the world have urinary or vaginal infections, including yeast vaginitis and bacterial vaginosis. Vaginal use of probiotics offers a potential alternative approach to health restoration and maintenance of the vaginal microflora. Moreover, prebiotics may be combined with probiotics to obtain a symbiotic effect. The aim of this work was to develop pro- and pre-biotics-loaded bioadhesive microparticles by using pectin and hyaluronic acid (HA). Four probiotic strains classically used in vaginal applications and one prebiotic have been selected. Microparticles were produced by emulsification/gelation method using calcium as cross-linking agent. The study of process and formulation parameters allowed obtaining microparticles with a mean diameter of 140 µm which encapsulated between 1010 to 1011 cfu/g of microparticles. Their mucoadhesive properties have been proved both by rheological and indentation measurements in in-vitro and ex-vivo conditions. Moreover, results have shown that HA addition in pectin solutions enhanced the bioadhesive properties of the gel-based microparticles. Afterwards, microparticles have been incorporated inside tablet by wet granulation. Microencapsulation of probiotics allowed protecting them during the compression process. The kinetic release of probiotics studies in in-vitro conditions exhibited a sustained release profile for 10 hours against 1h for unencapsulated probiotics. A beginning of probiotic strain proliferation was observed between 16 to 24 hours. The developed tablet is well-suited to vaginal applicatio

Improvement of an encapsulation process for the preparation of probiotics-laoded bioadhesive particles by using experimental design

International audienc

Morphological and Functional Evaluation of Chicken Blood Leukocytes in Chronic Ochratoxicosis

Abstract: The effects of ochratoxin A (OA) administration on the function and morphology of chicken blood leukocytes was evaluated. Two-weeks-old, broilers chickens (Cobb-500) were randomly divided into three groups, six birds each. The birds form the group I received a fodder without ochratoxin. The chickens from the group II were fed with fodder containing 6ppm of ochratoxin A for 10 days, while administration of ochratoxin to the birds from group III was prolonged up to 20 days. After 10 days of administration the OA containing fodder, there was recorded the increase of hematocrit (PCV) and characteristic for stress, decrease of lymphocyte percentage with simultaneous increase of heterophils percentage. The prolonged administration of the OA containing fodder to the subsequent 10 days, lead to the withdraw of the mentioned leukogram changes, decrease of PCV value and decrease of hemoglobin (Hb) level. Simultaneously, there was demonstrated that the heterophils of the chickens receiving OA, characterized with increased phagocytosis ability of the yeast cells (17 % of phagocytizing cells in the group I, while in group II and III 26 and 37 % respectively). However, the lymphocytes of these birds, after their incubation with oxalates mixture, characterized with decreased ability of radial segmentation of their nuclei (11.4 % in the group I, 8 % in the group III). The obtained results show not only OA immunosuppressive activity mechanisms, but also indicate the dissimilar or even very different sensitiveness of the particular leucocytes