Marcin Śmiałek

An evaluation of the impact of aloe vera and licorice extracts on the course of experimental pigeon paramyxovirus type 1 infection in pigeons

Abstract The progressive decrease in the efficiency of synthetic drugs has prompted research into phytogenic feed additives with potentially immunomodulatory and anti‐infective properties. Complex diseases with a mixed etiology, including viral, pose a growing problem in domestic pigeons. The aim of this study was to determine the effectiveness of various doses of aloe vera and licorice extracts on the course of experimental PPMV‐1 infection in pigeons. The experiment was performed on pigeons divided into 5 groups, including one control group and 4 experimental groups, which were orally administered aloe vera or licorice extracts at 300 or 500 mg/kg BW for 7 d after experimental inoculation with PPMV‐1. On d 4, 7, and 14 after inoculation, cloacal swabs and samples of organs were collected from 4 birds in each group. The samples were analyzed to determine the copy number of PPMV‐1 RNA by TaqMan qPCR. The results indicate that licorice and aloe vera extracts inhibited PPMV‐1 replication by decreasing viral RNA copy numbers in the examined organs. The most inhibitory effect was observed in pigeons receiving aloe vera extract at 300 mg/kg BW, for which PPMV‐1 RNA copy numbers were approximately 7‐fold lower (brain), 9‐fold lower (kidneys), and 14‐fold lower (liver) than in the control group. The results of this study point to the potentially antiviral effects of aloe vera and licorice extracts in pigeons infected with PPMV‐1. To the best of our knowledge, this is the first study to investigate the antiviral properties of aloe vera and licorice extracts in domestic pigeons.

Application of pigeon circovirus recombinant capsid protein for detecting anti-PiCV antibodies in the sera of asymptomatic domestic pigeons and the potential use of a combination of serological and molecular tests for controlling circovirus infections in pigeon breeding flocks

&NA; The aim of this study was to evaluate the serologic status of domestic pigeons not infected and asymptomatically infected with the pigeon circovirus (PiCV) with the use of an enzyme‐linked assay based on PiCV recombinant capsid protein as a plate antigen. Recombinant PiCV capsid protein was produced by transforming E. coli BL21 (DE3) Rosetta colonies with expression plasmids. Blood samples and cloacal swabs were collected from 171 asymptomatic pigeons. The birds were divided into two groups (infected and not infected with PiCV) based on the results of Sybr Green real time PCR screening for the presence of PiCV genetic material. Approximately 70% of the pigeons tested positive for anti‐PiCV antibodies regardless of their infection status. Antibody levels, the coefficient of variation and standard deviation were significantly higher in the group of infected pigeons. The results indicate that ELISA is a highly useful test that complements molecular methods in evaluations of PiCV infection status in domestic pigeons. The spread of pigeon circovirus infections can be controlled by keeping breeding flocks free of PiCV, which can only be achieved by subjecting birds to real time PCR and serological tests.

Identification of Transmissible Viral Proventriculitis (TVP) in broiler chickens in Poland

The aim of the study was to investigate the possibility of Transmissible Viral Proventriculitis (TVP) occurrence in broiler chickens in Poland. In march 2016 proventriculi samples were collected from broiler chickens showing poor uniformity and decreased body weight, accompanied by enlarged proventriculi. Histopathological examination of affected proventriculi revealed typical lesions associated with TVP (vacuolar degeneration and necrosis of glandular epithelium, replacement of glandular epithelium by hyperplastic ductal epithelium and moderate to severe lymphocytic infiltration). To our best knowledge, up to date there is no report indicating the presence of TVP in Poland nor in Central and Eastern Europe.

Detection of Bordetella avium by TaqMan real-time PCR in tracheal swabs from wildlife birds

Bordetella avium, the causing agent of bordetellosis, a highly contagious infection of the respiratory tract in young poultry, causes significant losses in poultry farming throughout the world. Wildlife birds can be a reservoir of various pathogens that infect farm animals. For this reason the studies were conducted to estimate the prevalence of Bordetella avium in wildlife birds in Poland. Tracheal swab samples were collected from 650 birds representing 27 species. The bacterial DNA was isolated directly from the swabs and screened for Bordetella avium by TaqMan real-time PCR. The assay specificity was evaluated by testing DNA isolated from 8 other bacteria that can be present in avian respiratory tract, and there was no amplification from non-Bordetella avium agents. Test sensitivity was determined by preparing standard tenfold serial dilutions of DNA isolated from positive control. The assay revealed to be sensitive, with detection limit of approximately 4.07x10^2 copies of Bordetella avium DNA. The genetic material of Bordetella avium was found in 54.54% of common pheasants, in 9.09% of Eurasian coots, in 3.22% of black-headed gulls and in 2.77% of mallard ducks. The results of this study point to low prevalence of Bordetella avium infections in wildlife birds. The results also show that described molecular assay proved to be suitable for the rapid diagnosis of bordetellosis in the routine diagnostic laboratory.

Practical aspects of estimation of optimal time for vaccination of chicken against IBD with use of "Deventer formula".

One of the most commonly applied vaccination strategies against chicken infectious bursal disease (IBD) is the use of live vaccines at the optimal time estimated with the use of Deventer formula. The present study investigated the impact of different factors on maternally derived antibodies decline and therefore on the vaccination schedule against IBD. Our results suggest that blood collection from birds older than 3 days is more reliable in order to estimate the optimal date for IBD vaccination, due to disturbances in yolk sac resorption early after hatch.

Three-step Anti-aMPV IgA Expression Profile Evaluation in Turkeys of Different Immunological Status after TRT Vaccination.

Maternally derived antibodies (MDA) don not protect turkeys against rhinotracheitis (TRT) but high MDA influences upper respiratory tract (URT) immunity stimulation after avian Metapneumovirus (aMPV) vaccination. Humoral immunity can not be considered as an indicator of protection against TRT, but specific antibodies inhibit aMPV replication and alleviate the course of TRT. Scarce reports indicate the role of IgA in protection against TRT. The aim of our study was to investigate the impact of MDA on stimulation, antigen specificity acquisition of B lymphocytes, and the production of specific IgA after TRT vaccination of turkeys. The results of our study indicate that MDA on the day of TRT vaccination causes disturbances at different levels of specific humoral immunity expression including antigen specificity acquisition of B IgA+ lymphocytes as well as production and secretion of IgA. Vaccine immunity against aMPV associated with sIgA is well expressed in birds not possessing MDA on the day of TRT vaccination, whereas it is inhibited in MDA+ birds. These results corroborate our previous findings and indicate that MDA could be responsible for TRT vaccination failure. These findings could explain the observed frequency of TRT field outbreaks despite aMPV vaccination of turkey flocks.

Epidemiological situation of turkey coryza (bordetellosis) in Poland

The present study investigated the prevalence of Bordetella avium (BA) infections in turkey flocks of different production type in Poland, based on serological examination of blood samples collected between 2012 and 2014. The results of our study indicate that BA infections are very common in turkey flocks, they are possible during the whole production cycle and that probability of the past infection increases with age. This situation is causing high level of specific anti-BA maternally derived antibody transfer to hatching poults.

The influence of phytoncides on the immune system of broiler chickens and turkeys.

The aim of our study was to investigate the influence of adiSalmoSOL PF dietary supplement, given for 3 days in drinking water, on selected parameters of cell-mediated (Experiment I) and humoral (Experiment II) immunity in chicken and turkey broilers. In Experiment I, birds were randomly divided into two groups of 10 birds each. Group 1 comprised control turkeys or chickens, whereas group 2 birds were administered adiSalmoSOLPF. In Experiment II, a total of 69 chickens were divided into three groups (1-3) of 23 birds each. At the age of 25 days, group 1 was given adiSalmoSOLPF. Birds from groups 1-3 were vaccinated at 28 days of age. Group 2 was given adiSalmoSOLPF after vaccination. In Experiment I, a significant increase in percentages of CD4 + T lymphocytes in the bursa of Fabricius, cecal tonsils and spleen, CD8 + T lymphocytes in the thymus and spleen, CD4 + CD8 + T lymphocytes in the bursa of Fabricius and ileal mucosa and IgM + B lymphocyte in the ileal mucosa were observed in group 2 chickens. In Experiment I, a significant increase in percentages of CD4 + T lymphocytes in the thymus and spleen, CD8+ T lymphocytes in the cecal tonsils and blood, and CD4 + CD8 + T lymphocytes in the thymus and ileal mucosa was recorded in group 2 turkeys. No differences in percentages of IgM + B lymphocytes were observed between turkey groups. In Experiment II, the highest post-vaccination titers of anti-IB antibodies were observed in group 2, but it was not statistically significant. The results of our study indicate that adiSalmoSOLPF showed immunomodulatory activity in chickens and turkeys.