• Journal of Veterinary Science
• /
• v.23 no.2
• /
• pp.21.1-21.7
• /
• 2022

Newcastle disease (ND), infectious laryngotracheitis (ILT) and avian metapneumovirus (aMPV) can be similar making it critical to quickly differentiate them. Herein, we adapted pre-existing molecular-based diagnostic assays for NDV and ILTV, and developed new assays for aMPV A and B, for use under synchronized thermocycling conditions. All assays performed equivalently with linearity over a 5 log₁₀ dynamic range, a reproducible (R² > 0.99) limit of detection of ≥ 10 target copies, and amplification efficiencies between 86.8%-98.2%. Using biological specimens for NDV and ILTV showed 100% specificity. Identical amplification conditions will simplify procedures for detection in diagnostic laboratories.

• Korean Journal of Veterinary Service
• /
• v.37 no.3
• /
• pp.185-190
• /
• 2014

We investigated the serological prevalence of avian metapneumovirus (AMPV), avian reovirus (ARV), Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) in 760 broiler breeder (38 flocks), in the Jeonbuk province in 2013. This study was conducted to evaluate the immune and infection status of the broiler breeder flocks against AMPV, ARV, MG, MS by an enzyme-linked immunosorbent assay (ELISA). Serological test for AMPV were positive 37 (97.3%) flocks and 712 (93.6%) broiler breeder and geometric mean antibody titers were $16,350{\pm}10,195$, ARV were high positive rate 100% (38/38) flocks and 97.8% (743/760). The seropositive flocks against MG were 71.1% (27/38) and the geometric mean antibody titers were $2,474{\pm}2,045$, whereas the rates of positive flocks against MS were 50.0% (19/38) and the geometric mean antibody titers were $1,469{\pm}1,230$.

• Korean Journal of Poultry Science
• /
• v.46 no.4
• /
• pp.235-247
• /
• 2019

Serological monitoring has been conducted worldwide for early diagnosis of disease and monitoring of immune status in poultry. This study was conducted to evaluate the immune status of layers with sera submitted to the Avian Disease Laboratory, Chungbuk National University from 2015 to 2017. The test results were analyzed by the time submitted and by the age of the chicks. Low pathogenic avian influenza (LPAI) showed a low positive rate of antibody compared with those of Newcastle disease, indicating that domestic vaccination against LPAI was not sufficient. The antibody profile of infectious bronchitis (IB) depicted high level of titer and a low tendency of CV as compared to the uninfected control flocks, which indicated that most layer farms have been exposed to the field IB virus. In case of avian metapneumovirus infection (aMPV) and Mycoplasma synoviae (MS), since the introduction of the vaccine in 2011 and 2017, respectively, the positive rate and the titer level were higher than those in pevious times. No significant difference in the changes of seasonal result was observed, indicating proper vaccination and improvement in biosecurity and management.

• Korean Journal of Poultry Science
• /
• v.37 no.4
• /
• pp.361-372
• /
• 2010

Serological evaluation for the poultry is important for various reasons, such as designing and assessing the vaccination program and diagnosing diseases and for this reason, serologic tests for the layer flocks have been conducted on a regular basis. Moreover, the nationwide serological survey and analysis are essential to understand the epidemiological status of national poultry industry. In this sense, the study was conducted to evaluate the immune status of the layer flocks with the sera submitted to Avian Disease Laboratory, Chungbuk National University in 2009, and several important viral diseases were selected for evaluation including low pathogenic avian influenza (LPAI), Newcastle disease (ND), infectious bronchitis (IB) and avian metapneumovirus (aMPV). For LPAI and ND, the age-related patterns of geometric mean titer (GMT) changes were similar but there were differences in the flock positive rate and the level of GMT due to the different vaccination policy. In the case of IB, the values of GMT showed that the field infection was more prevalent than expected. For aMPV, positive birds in a flock increased as the layers got older, which reflected the course of field infection because vaccination against aMPV was not allowed in 2009. From this study, the immune status for the main viral diseases in layers became more clarified but this information was limited because of only one year study. Therefore, serological survey needs to be conducted on a yearly basis and furthermore include broilers and breeders for a better understanding of the health status in the national poultry industry.