Reverse transcriptase-polymerase chain reaction-based surveillance of type A influenza viruses in wild and domestic birds of the Lebanon.

A total of 1 330 oropharyngeal swabs collected from wild and domestic birds in Lebanon were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) for type A avian influenza virus (AIV) during the migratory season between the autumn of 2005 and winter of 2006. Twenty-five species of birds were included in the study. There are 14 species of migratory wild birds, 4 species of resident wild birds, 3 species of pet birds and 4 species of farm birds. The number and percentage of positive type A avian influenza viruses in collected oropharyngeal swabs was 190 positive out of 1 330 samples tested (14.3%). The 190 oropharyngeal samples positive for AIV were further tested by specific RT-PCR for H5 and H7 subtypes. The 190 AIV-positive samples were all negative for H5, while 13 of the 190 (6.8%) were positive for H7. The H7-positive samples were confined to sparrows (resident wild bird species) and to backyard chicken in the south province, located 10-20 km from the Israeli-Lebanese border.

Holistic efficacy of specific nutrient synergy against avian flu virus: pathology and immunomodulation.

The authors evaluated the holistic efficacy of nine specific nutrient synergy (NS) against avian influenza virus (AIV) strain Lebanon 1 (H9N2). The study included two segments; the first was designed to determine the minimum dose among four doses (1X, 2X, 3X and 4X in which X = 24.4 mg/ml/bird) of NS, administered intraoesophageally, once per day between 7 and 14 days of age, resulting in an improvement of chicken performance without any toxic side-effects; the second aimed at reducing pathological effects and inducing immunomodulation by the determined safe dose of NS in chickens exposed to AIV. The first segment showed that the daily oral administration of the NS to birds between 7 to 14 days of age at the 2X dose-level (320 mg/kg body weight or 48.8 mg/ml/bird) resulted in a consistent and significant improvement in the feed conversion (P<0.05) at 10 and 14 days of age, associated with a significant (P<0.05) increase in the liver weight index. In addition, the administration of NS at 2X level resulted in complete absence of toxicity signs (swollen infraorbital sinuses, ocular exudate, nasal discharge, thick oral saliva, diarrhoea, lameness and huddling) and complete absence of toxicity lesions (airsacculitis, hydropericardium signs, pericarditis, perihepatitis, splenomegaly and tracheitis). The four groups of birds that received levels 1X to 4X levels had significantly higher frequency of birds with gaseous caeca compared to the control group deprived of NS (P<0.05), a sign of higher fermentation activity in this organ. Data from the second segment of this research showed that the daily administration of NS at a level of 48.8 mg/ml/bird, between 7 to 14 days of age, to H9N2-challenged birds reduced specific pathological effects at 14 days of age namely: absence of rales at 3 days post H9N2 challenge and gross lesions (absence of tracheitis and enteritis at 7 days post challenge). Such reductions in signs and gross lesions were associated with a 63.4% reduction in immune responses to the hemagglutinin protein of the AIV, an indication that NS has a reducing effect on the viral infectivity in chickens.

Preliminary study on the efficacy and safety of eight individual and blended disinfectants against poultry and dairy indicator organisms.

Eight individual and blended chemical disinfectants were screened for preliminary evaluation of safety, bactericidal and virucidal effectiveness against poultry and dairy organisms. The test organisms were Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus, Streptococcus spp. and Clostridium perfringens, in addition to avian influenza virus (AIV) and Newcastle disease virus (NDV). Viable counts of surviving bacteria were determined after 30 min contact with each disinfectant and in the presence or absence of skimmed milk, to simulate the interference of organic matter. The haemagglutination test was used to assess the survival of the test viruses in the presence of the different disinfectants after propagation in 10-day-old chick embryos. In the presence of skimmed milk, a higher concentration of most of the disinfectants examined was required to exert antimicrobial effectiveness. When used individually, quaternary ammonium showed no virucidal activity against NDV and AIV; peracetic acid was not effective against Streptococcus spp., S. Enteritidis and NDV, while iodophors showed low bactericidal and inconsistent virucidal activity. The single and blended disinfectants with high microbicidal activities included phenols (high bactericidal and virucidal activity), blends of quaternary ammonium compounds (high bactericidal activity) and blends of cresols and organic acids (high virucidal activity). This suggests the use of blends of compatible compounds for disinfection operations in poultry and dairy industries since they will target a wider range of micro-organisms. None of the disinfectants had a negative effect on the development of the different organs of chicken embryos and the iodine-based disinfectant, developed for dairy-teat dipping, also showed no adverse reactions in experimental cows.