| Popis: |
Newcastle disease (ND) remains one of the major diseases ravaging the poultry industry in Nigeria. Vaccination of birds is carried out to protect birds against the disease. Despite vaccination against ND, birds still come down with the disease. This study was conducted to determine the potency of ND vaccines sold at different veterinary outlets in Abeokuta. Newcastle disease vaccines were purchased from three veterinary outlets (I, II and III) in Abeokuta over a period of 3 weeks and the haemagglutination (HA) titre determined. A total of 50 broiler chicks were also purchased and divided into 4 groups A-D. Groups A-C had 12 birds each and vaccinated against ND while Group D (Control) had 14 birds and were not vaccinated against ND. Groups A-C were vaccinated with ND vaccines with different HA titre and the antibody response determined using haemagglutination inhibition (HI) assay. Varying haemagglutination titre was recorded for all the vaccines purchased from the three outlets. The first batch of vaccines had haemagglutination titre of 0log2, 6log2 and 0log2 for outlets A, B and C respectively. The second batch had 6log2, 7log2 and 5log2 while the third batch had 4log2, 3log2 and 3log2 for outlets A, B and C respectively. Antibody titre stimulated in vaccinated birds by the second batch of vaccines for groups A, B and C birds were 1536log2, 1792log2 and 768log2 respectively, while the control birds had HI titre of 5log2. It is recommended that veterinary outlets improve the storage of vaccines, vaccine potency test be carried out on vaccines regularly and seromonitoring for humoral immune response in vaccinated chicken flocks be carried out for successful control of Newcastle disease. |
