title: Isolation of Infectious Bursal Disease Virus Using Indigenous Chicken Embryos in Kenya.
abstract: Infectious bursal disease virus (IBDV) isolates were recovered from outbreaks to initiate activities towards developing a local vaccine strain. Use of indigenous chicken embryos was exploited to determine their potential, promote utilization of local resources for research, and enhance household economic activities. Bursa of Fabricius (BFs) samples from outbreaks shown to be IBDV positive was homogenized and inoculated in 4-week-old specific pathogen-free (SPF) IBDV seronegative white leghorn chicks. The harvested virus was inoculated into 11-day-old indigenous chicken embryos that were IBDV seronegative and passaged serially three times after which they were inoculated into 4-week-old indigenous chicks to test for presence and virulence of propagated virus. Out of 153 BFs collected from outbreaks, 43.8% (67/153) were positive for IBDV antigen and 65.7% (44/67) caused disease in SPF chicks. The embryo mean mortalities were 88% on primary inoculation, 94% in 1st passage, 91% in 2nd passage, and 67% in 3rd passage. After the third passage in embryos all the 44 isolates were virulent in 4-week-old indigenous chicks. The results show that indigenous chicken embryos support growth of IBDV and can be used to propagate the virus as an alternative viral propagating tool for respective vaccine preparation.
authors.affiliation: State Department of Livestock, Regional Veterinary Investigation Laboratories, P.O. Box 204-80113, Mariakani, Kenya.
authors.forename: W U
authors.initials: WU
authors.lastname: Mutinda
authors.affiliation: University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
authors.forename: L W
authors.initials: LW
authors.lastname: Njagi
authors.affiliation: University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
authors.forename: P N
authors.initials: PN
authors.lastname: Nyaga
authors.affiliation: University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
authors.forename: L C
authors.initials: LC
authors.lastname: Bebora
authors.affiliation: University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
authors.forename: P G
authors.initials: PG
authors.lastname: Mbuthia
authors.affiliation: University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
authors.forename: D
authors.initials: D
authors.lastname: Kemboi
authors.affiliation: State Department of Livestock, Central Veterinary Laboratories, Private Bag Box 00625, Nairobi, Kenya.
authors.forename: J W K
authors.initials: JW
authors.lastname: Githinji
authors.affiliation: Kenya Veterinary Vaccine Production Institute (KEVEVAPI), P.O. Box 53260-00200, Nairobi, Kenya.
authors.forename: A
authors.initials: A
authors.lastname: Muriuki