The modulatory effect of carvacrol on viral shedding titer and acute phase response in broiler chickens experimentally infected with infectious bronchitis virus.

Infectious bronchitis virus (IBV) is one of the major respiratory diseases of broiler causing huge economic losses. The inability to control IBV using different vaccination programs owing to the high mutation rate and recombination ability of the RNA genome generates IBV variants. This study was designed to give a specific perspective of carvacrol effect on early immune response, viral shedding titer, oxidative stress, serum biochemical parameters and clinical consequences in broilers experimentally infected by IBV. One hundred and twenty-one-day old commercial broiler chicks were equally divided into 4 groups. First group was considered as control. Second group was given carvacrol, third group was infected with IBV and fourth group was given carvacrol and infected with IBV. Infection with variant IBV induced significant upregulation of chicken interferon-inducible transmembrane protein 3 (chIFITM3) gene in trachea, elevations in serum levels of Alpha-1 acid glycoprotein (α1-AGP) and Interleukin 6 (IL-6), total leucocytic count (TLC), heterophil/lymphocyte (H/L) ratio and oxidative stress in lung and kidney tissues. Beside, histopathological changes in trachea, lung and kidney induced by IBV, elevation of kidney function tests was detected. The pretreatment with carvacrol significantly reduced viral shedding titer, chIFITM3 gene expression, IL-6 and α1-AGP levels, leucocytic response and H/L ratio with minimization of clinical signs intensity. Also, carvacrol relieved oxidative stress, ameliorated the increased uric acid level and histopathological alterations in kidney and lung caused by viral infection.

Immunostimulant effect of Egyptian propolis in rabbits.

The present experiment was conducted to study the effect of ethanolic extract of Egyptian propolis given alone or in combination with inactivated Pasteurella multocida vaccine on rabbits challenged with a virulent strain of Pasteurella multocida. Fifty-six New-Zealand rabbits, 6-8 weeks old and non-vaccinated against pasteurellosis, were randomly divided into eight equal groups. The first group was kept as a control for the experiment. The other groups received different treatments with propolis extract, inactivated vaccine, or both. The experiment continued for seven weeks during which clinical signs, body weight, and mortality rate were monitored, and blood samples were collected weekly for evaluating the leukogram, serum biochemistry, and immune response in all groups of animals. At the end of the seventh week, the animals were subjected to challenge with a virulent strain of Pasteurella multocida. Two weeks later, tissue specimens were collected from different organs for histopathological examination. Results showed that rabbits of the groups treated with both propolis and the vaccine by different routes appeared healthy after challenge. It has been concluded that alcoholic extract of propolis administrated in combination with inactivated Pasteurella multocida vaccine has no adverse effects on the general health conditions and enhances immune response in rabbits.

Evaluation of the curative effect of Balanites aegyptiaca fruits ethanolic extract on Haemonchosis experimentally induced in Egyptian Baladi goats: phytoanalytical, parasitological and hematological studies.

This study aimed to screen phytochemical components and antioxidant activity of Balanites aegyptiaca ethanolic extract (BAF-EE) as well as to evaluate its curative effect on experimentally induced haemonchosis in goats. Phytochemical constitutes of BAF-EE were screened and identified using Gas Chromatography-mass Spectrometry (GC-MS) analysis and antioxidant effect was determined. Infective third larval stage (L3) of Haemonchus contortus (H. contortus) were obtained by culturing feces of goat harboring monospecific infection of the parasite. Twelve male goats were randomly divided into four groups (n = 3) as: G1 (infected-untreated) which served as control positive, G2 (infected-BAF-EE treated), G3 (infected-albendazole treated) and G4 (uninfected-BAF-EE treated) that served as control negative. Experimental infection was conducted with a single oral dose of 10,000 L3 at 0-time, whereas treatment with BAF-EE and albendazole were given at a single oral dose of 9 g and 5 mg/kg BW, respectively in the 5th week post infection (PI). Egg count per gram of feces (EPG) was conducted once a week and blood samples were drawn on zero time, 3rd week PI and then biweekly for 9 weeks, for conduction of hemogram. At the end of the experiment, all animals were slaughtered and adult worms in their abomasa were counted. GC-MS analysis confirmed 28 compounds in the extract which revealed presence of saponins, flavonoids, terpenoids, phenolics and alkaloids, and exhibited in vitro antioxidant activity. Clinical signs observed on the infected animals were signs of anemia, which were gradually disappeared post treatment (PT). A maximum reduction in EPG (88.10%) and worm burden (94.66%) was recorded on 4th week PT due to efficacy of BAF-EE in contrast to 98.29% and 96.95% efficacy of albendazole. All infected groups showed a significant decrease in hemoglobin (Hb) and packed cell volume (PCV) and presence of microcytic hypochromic anemia compared with G4. Goats treated with B. aegyptiaca and albendazole, exhibited significant increase in Hb and PCV 2 weeks PT and anemia changed to be normocytic hypochromic or microcytic normochromic in G2 and G3, respectively. Total white blood cells (WBCs) were elevated significantly in all infected groups which attributed to increase in lymphocytes, monocytes and eosinophils on expense of neutrophils. After treatments, WBCs and previously mentioned cells tended to decease. This study demonstrated that BAF-EE has anthelmintic effect against H. contortus and can improve hemogram and health condition of infected goats.

Hepatitis E virus infection in work horses in Egypt.

Hepatitis E virus (HEV) is an important cause of hepatitis among young Egyptian adults with high seroprevalence rates seen in both rural areas of the Nile Delta and in suburban Cairo. Because natural antibodies to HEV have been detected in animals and zoonotic transmission is postulated, we surveyed work horses in Cairo for evidence of HEV exposure and viremia. Sera from 200 Cairo work horses were tested by ELISA for the presence of IgG anti-HEV antibody revealed a seropositivity of 13%. Among 100 samples processed for detection of viral genome by means of nested polymerase chain reaction (N-PCR), 4% were positive and indicative of viremia. Viremic animals were less than 1 year old. Relative to PCR-negative horses, PCR-positive animals demonstrated significant elevation of AST (p=0.03). Phylogenetic analysis of a 253-bp fragment, in the ORF-1,2,3 overlap region of the HEV genome from the viremic animals showed that three of these viral strains to be identical, and closely related (97-100% nucleotide identity) to two human isolates from Egypt, and distant (78-96%) from 16 other HEV isolates from human and animals and shared 99.6% NI with the fourth strain. The consensus sequence of the four strains was origin obtained elsewhere. These data indicated that horses acquire HEV infection and suggest that cross-species transmission may occur. Whether horses play a role in the transmission of HEV needs further investigation.

Studies on parasitologic and haematologic activities of an enaminone derivative of 4-hydroxyquinolin-2(1H)-one against murine schistosomiasis mansoni.

The activity of a novel enaminone derivative of 4-hydroxyquinoline, BDHQ, was screened for its effectiveness against murine schistosomiasis by electron microscopy and parasitologic studies. The correlation of these studies with serum levels of IFN-gamma and IgE is described. Two groups of 10 mice each were treated with different doses of BDHQ, and their results were correlated with the control and praziquantel (PZQ)-treated groups. Parasitologic study revealed significant reduction in mature worms and tissue egg loads in BDHQ- and PZQ-treated groups, whereas immature worms revealed significant reduction in BDHQ groups only. The group treated with a higher dose of BDHQ showed significant reductions in intestinal ova count when compared with the PZQ-treated group. Ultrastructural examination of the worm revealed significant degeneration of the spines and tegument in all treated groups, while the genital system was affected in BDHQ-treated groups only. BDHQ showed considerable effect on cellular activation where serum levels of IFN-gamma were significantly increased in comparison to control, while anti-soluble worm antigen preparation (SWAP) IgE was significantly increased in comparison to both the control and PZQ-treated groups. Ultrastructural examination revealed cellular activation in buffy coat and the liver in both the BDHQ- and PZQ-treated groups in comparison to the untreated one, whereas in the bone marrow and spleen, evidence of cellular activation was remarkable in the BDHQ-treated groups. In conclusion, BDHQ exhibits high levels of activity against adult and juvenile stages of these parasites, which may be due to its mixed cellular and humoral immunologic mechanisms, as demonstrated by the significant increase of serum levels of IgE and IFN-gamma shown on electron microscopy. Therefore, our results support the comparative advantage that BDHQ has over PZQ.

IMMUNE RESPONSE OF STIMULATED BIOMPHALARIA ALEXANDRINA SNAILS WITH SCHISTOSOMA MANSONI INFECTION.

In this study, both digestive and hermaphrodite glands in Biomphalaria alexandrina snails were examined by light microscope (LM) and scanning electron microscopy (SEM) in a trial to clarify its immunological role as defense mechanism against the parasite infection. B. alexandrina snails used were exposed individually to Schistosoma mansoni miracidia; according to their responsq they were classified into infected snails (shed cercariae) and non-infected snails (failed to shed cercariae). Snails not exposed to S. mansoni miracidia used as control. LM showing great histological alteration in tissues, of the both glands in infected snails, these changes represented by degenerated both oocyte and spermatocyte in hermaphrodite gland in addition to degenerated digestive gland while non-infected snails showing mild degenerated ova with normal spermatocytes also degenerated miracidia. inside granuloma like structure with concentric layers of fibroblast and haemocyte could be observed. By SEM we could detect extensively damaged and fibrosed non-motile cilia with exfoliation of tegumental surface in in- fected B.alexandrina while non-infected ones showing attached numerous cilia with some ballooning of the folds.

Ultrastructural study on Biomphalaria alexandrina haemocytes infected with Schistosoma mansoni in Egypt and its correlation with nitric oxide level.

Some snails of Biomphalaria alexandrina can resist the infection of Schistosoma mansoni so this study aimed to clearly this mechanism by using light and electron microscopy (EM) and determine the role of Nitric oxide in this mechanism. B. alexandrina snails used in this study were exposed individually to S. mansoni infection according to their response they were classified into susceptible group (shed cercariae) and resistant group (failed to shed cercariae). Snails not exposed to infection were included in this study as control group. Nitric oxide (NO) level was assayed directly in the soluble fraction of B. alexandrina haemolymph supernatants collected from each group of B. alexandrina snails were subjected to NO assay by the Greiss reaction. The level of NO in haemolymph of infected snails was significantly increased (p < 0.001) than both control and non infected snails groups, however, in non infected snails group had significantly (p < 0.05) compared to control group. This study when correlated the changes recognized by EM with NO level the pro apoptotic effect of high level of NO on the haemocytes. Characterization and identification of cell shape of haemocytes in both haemolymph and tissue were examined by light and electron microscopy. Examination of B. alexandrina snail's haemocytes revealed three types of different cells classified according to their shape and granular contents. These cells are granulocytes, amoebocytes and hyalineocytes. Electron microscope study also revealed the important role of granulocytes and amoebocytes as defense mechanism against snail infection. NO is considered an important anti parasite molecule; intra-molluscan stages of parasites switch off host NO defense response.

Protective effect of Egyptian propolis against rabbit pasteurellosis.

The present study was conducted to study the protective effect of ethanolic extract of propolis given subcutaneously (S/C) either alone or in combination with inactivated formalized Pasteurella multocida (P. multocida) vaccine in rabbits challenged with virulent P. multocida strain. Twenty-eight New-Zealand rabbits, 6-8 weeks old and not vaccinated against pasteurellosis, were randomly divided into four equal groups. Group (1) was kept as nonvaccinated control. Group (2) was injected S/C with propolis. Group (3) was vaccinated (S/C) with P. multocida vaccine only. Group (4) was injected with vaccine mixed with propolis as adjuvant. Groups (2, 3, and 4) received the same doses of propolis and vaccine after 4 weeks as a booster dose. The experiment continued for six weeks during which clinical signs, body weight, and mortality rate were recorded. Blood samples were collected every 2 weeks of treatment for evaluating the erythrogram and biochemical parameters. At the end of six weeks, all groups were subjected to challenge with a virulent strain of P. multocida. Two weeks later, tissue specimens were collected from different organs for histopathological investigation. Results showed that before challenge all rabbits of different groups were apparently healthy and had good appetite. After challenge, control group (1) showed acute form of the disease, 100% mortality rate, and severe histopathological changes. Rabbits of groups (2 and 3) showed less severe clinical signs, mortality rate, and histopathological changes than control. Rabbits of group (4) were apparently healthy with normal histological picture. In conclusion, an ethanolic extract of propolis injected alone or combined with formalized inactivated P. multocida vaccine improved general health conditions, liver and kidney functions in addition to reduction of the severity of adverse clinical signs, mortality rates, and histopathological changes associated with challenge of rabbits with P. multocida strain.

Immunolocalization of Schistosoma mansoni and Schistosoma haematobium antigens reacting with their Egyptian snail vectors.

The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails.

Parasitological, hematological and ultrastructural study of the effect of COX-2 inhibitor, pyocyanin pigment and praziquantel, on S. mansoni infected mice.

The effect of cyclooxygenase-2 (COX-2) inhibitor, such (as meloxicam, and pyocyanin pigment of Pseudomonas aeruginosa) with and without praziquantel (PZQ) on worms, ova count, bone marrow and blood cells in 7 groups of Schistosoma mansoni infected mice was studied. The results revealed significant decrease of worm burden and ova count in all treated groups as compared to the infected untreated group, while those with combined treatment of PZQ and meloxicam or pyocyanin showed complete eradication of the worm with the highest reduction in the tissue egg load. EM showed extensive swelling and vesiculation of the tegument, completely implanted spines that overlie degenerated muscle layer were obvious in groups treated with either meloxicam or pyocyanin. Hematological study revealed significant increase (P<0.05) of total leucocytic count of PZQ treated group while that treated with either meloxicam or pyocyanin showed significant decrease (P<0.05), but in combination of PZQ with meloxicam or pyocyanin no significant difference as compared to the infected untreated group. The neutrophil was the main cell affected in groups treated with neither meloxicam nor pyocyanin alone with significant decrease (P<0.05), but with significant increase (P<0.05) in combination with PZQ as compared to the infected untreated group. Those treated with PZQ plus meloxicam showed significant increase as compared to that plus pyocyanin. Eosinophil count showed significant decrease (P<0.05) in all treated groups as compared to the infected untreated group. Inverse correlation between serum level of sFas and peripheral neutrophil count was detected. Ultrastructural study of the bone marrow explained the results as groups treated with meloxicam revealed dissociation between nuclear and cytoplasmic development in the neutophils with cytoplasm maintaining primitive appearance despite maturation of the nucleus, that is manifested by the persistent production of immature granules and the still orientation of Golgi cternae and the centriole around the nucleus. Groups treated with pyocyanin pigment revealed many abnormalities in neutophils as hypogranularity or early apoptotic morphology changes as intense perinuclear chromatin aggregation or nucleus fragmentation. In peripheral blood apoptotic morphology changes was detected in both groups treated with meloxicam or pyocyanin while most of cells of mice treated with PZQ were in an active state. Consequently, it is preferable to give meloxicam with PZQ for a short period of time (less side-effect) to eradicate S. mansoni worm completely but with continuous observation of the peripheral neutrophil count and function.