Molecular detection and isolation of avian metapneumovirus in Mexico

Abstract

We conducted a longitudinal study to detect and isolate avian metapneumovirus (aMPV) in two highly productive poultry areas in Mexico. A total of 968 breeder hens and pullets from 2 to 73 weeks of age were analysed. Serology was performed to detect aMPV antibodies and 105 samples of tracheal tissue were collected, pooled by age, and used for attempted virus isolation and aMPV nested reverse transcriptase-polymerase chain reaction (nRT-PCR). The serological analysis indicated that 100% of the sampled chickens showed aMPV antibodies by 12 weeks of age. Five pools of pullet samples collected at 3 to 8 weeks of age were positive by nRT-PCR and the sequences obtained indicated 98 to 99% similarity with the reported sequences for aMPV subtype A. Virus isolation of nRT-PCR-positive samples was successfully attempted using chicken embryo lung and trachea mixed cultures with subsequent adaptation to Vero cells. This is the first report of detection and isolation of aMPV in Mexico.

Serological and Molecular Characterization of Avian Metapneumovirus in Chickens in Northern Vietnam

“…Sampling chickens of various age groups and performing serological and virological examinations enabled the finding that aMPV infections occurred in chickens of all ages in northern Vietnam. That finding was in line with several published studies that reported the detection of aMPV in chickens from different age groups, such as: 3-8 weeks [28,53], 6-16 weeks [57], or 36 weeks [58]. An explanation was that aMPV was able to infect chickens/turkeys of any age [59].…”

“…Reverse transcription was performed using the HiSenScript RH(-) RT PreMix kit (25087, iNtRON Biotechnology, Gyeonggi, Korea) at 45 • C for 60 min. The nucleic acid of aMPV was detected by nested RT-PCR following a previous publication's methodology [28], using Maxime PCR PreMix kit, i-StarMAX II (25281, iNtRON Biotechnology, Gyeonggi, Korea). The PCR reaction was composed of 1 µL cDNA or outer PCR product, 1.0 µL aliquot of each reverse/forward primer (10 pmol/µL each), and distilled water up to 20 µL.…”

“…Aside from the serology test, clinical specimens were examined for the presence of aMPV. To improve the sensitivity, the nested RT-PCR with primers specific to the subgroups A and B [28] was applied. Forty-four of the 256 samples (17.2%) were positive for aMPV subgroup B while none were positive for subgroup A.…”

“…On the other hand, some evidence indicated that multigenic factors contribute to the virulence of aMPV [64,65] and no genetic markers for virulence were reliable due to random mutation during the in vitro attenuation process [66]. At the time when this work was submitted, an aMPV strain (Ck.51, MZ393686) was successfully isolated on chicken embryo lung and trachea mixed cultures following the previous method [28]. Genetic analyses (not shown) revealed that the Ck.51 isolate had a 97% nucleotide identity and was closely related to the Chinese LN16 isolate (MH745147) for which its pathogenicity was demonstrated in vivo [55].…”

Detection of infectious bronchitis virus 793B, avian metapneumovirus, Mycoplasma gallisepticum and Mycoplasma synoviae in poultry in Ethiopia

“…A recent review of IBV in Africa (Khataby et al 2016) contained no papers from East Africa, although numerous strain variants, including some unique to particular countries, have been reported in North and West Africa and southern parts of the continent. Reports from other countries worldwide, such as Bangladesh, Mexico, Oman and Algeria, where the poultry sectors are transforming, all indicate that these respiratory pathogens are a common and widespread source of concern to the developing industries (Islam et al 2014; Rivera-Benitez et al 2014; Al-Shekaili et al 2015b; Sid et al 2015). Ethiopia and other countries in East Africa are likely to face the same problems as intensification of poultry farming continues.…”