Development of a real-time PCR technique to titrate chicken anemia virus vaccine and identification of associated risk factors that may cause immunization failures in breeders.
CAV, Immunity, Associated Risk Factors, Vaccine, Real Time PCR.
Chicken Anemia Virus (CAV) causes severe temporal aplastic anemia, erythroblast cell line destruction, thymus atrophy and immunosuppression. Subclinical infection is responsible for increasing feed conversion ratio, decreasing mean weight, complications by secondary infections, and breach of vaccine immunization. Verified by serological monitoring, there is a proven failure of immunization against anemia in this study animals and the most accepted hypothesis is that the cause is a failure in vaccination, probably caused by the low titer of the vaccine. The main objective was to standardize a CAV vaccine titration technique by real-time PCR and to identify risk factors that could cause immunization failures against the disease. The study was divided into two parts, the first one was focused on the titration, where it was necessary to standardize a sensitive and specific PCR technique for Anemia and to quantify several dilutions of vaccine to design a standard curve that can correlate the CT found in the technique with the quantity of viable genetic material contained in the sample. The second part aimed to analyze statistically, through a logistic regression model associated with Odds Ratios, a serological database of several lots of animals, to identify the set of information that best explains the relation of the risk factors with failure to antibodies production. The level of significance of each variable will be determined by the chi-square test (χ2) and the minimum established will be 5% (p <0.05). PCR standardization for detection was performed and is already being used as a diagnostic tool. Real-time PCR primers for curve design were purchased but have not yet arrived. The genetic material of the vaccines was collected and sent for quantification by fluorometry, but the results have not yet returned. Data from the serological analyzes were collected and compiled, but information from the animals lots is still lacking in order to the statistical analyzes can be performed. It is not yet possible to draw conclusions about the experiment.