The efficacy of coarse spray vaccination against pathogenic infectious bursal disease virus (IBDV) in commercial broilers was evaluated. Different coarse spray vaccination schedules using a commercial 2512 strain vaccine were compared with single or double drinking water application at 1 and/or 10 days of age. At 29 days of age, the chickens were challenged with the virulent Edgar strain of IBDV. Seven days postchallenge, severe gross bursal atrophy was observed in the unvaccinated-challenged birds. After challenge and regardless of the method of vaccination used, moderate-to-severe lymphoid depletion was observed, indicating challenge virus replication, later confirmed by reverse transcriptase-polymerase chain reaction and restriction fragment length polymorphism analysis. Coarse spray and drinking water vaccination induced protection against body weight loss. Significant differences (P < 0.05) were observed between the unvaccinated-challenged group (1483 g) and the birds vaccinated at 10 days of age by coarse spray (1812 g). The coarse spray vaccination also induced protection against challenge-induced gross bursal atrophy, as determined by bursal index values. After challenge, significant bursal atrophy was observed in the birds orally vaccinated at 1 day (0.61), 10 days (0.66), and 1 and 10 days (0.63) as well as the unvaccinated-challenged birds (0.62), but not in the coarse-spray-vaccinated groups that exhibited bursal indexes above 0.70 and did not differ from the unvaccinated-unchallenged control group. These results suggest that coarse spray vaccination can be considered as another tool to control IBDV in the field.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 52 • No. 2