Development and Competition of Three Parasitoid Wasps, <i>Brachymeria podagrica, Dirhinus himalayanus</i>, and <i>Nasonia vitripennis</i>, in Their Host, <i>Sarcophaga dux</i>, in Single and Mixed Infections

Laboratory trials were carried out to investigate the development of three entomophagous parasitoid wasps in preimaginal stages of Sarcophaga dux in monoinfections and mixed infections. Laboratory-raised postfeeding S. dux third-stage larvae were exposed to Brachymeria podagrica. After pupation, 50 of these fly puparia were brought in contact with pupal parasitoid Dirhinus himalayanus and 50 with Nasonia vitripennis, and the remaining 50 puparia were left as Brachymeria monoinfection. In three further trials, each set of 50 freshly pupated host puparia from the same source was exposed to N. vitripennis and D. himalayanus, as monoinfections and mixed infections, respectively. The uninfected control group consisted of 50 S. dux larvae that were kept separately under the same conditions. The percentages of successfully developed B. podagrica and D. himalayanus in monoinfections were 56 and 86%, respectively, and progeny of N. vitripennis hatched from 88% of the exposed host puparia. In mixed infections, N. vitripennis dominated over B. podagrica and D. himalayanus with rates of successfully infected hosts of 50 and 94%, respectively. The number of Nasonia progeny in these groups ranged from 4 to 49 and 5 to 43, respectively. Dirhinus himalayanus did not develop in the simultaneous infection with N. vitripennis. Not a single S. dux eclosed in the six experimental groups, while in the uninfected control group, 46 (92%) adult flies eclosed 11 to 14 days after the start of pupation. Since the three parasitoids emerge from flesh fly pupae, these insects can become important in criminal forensic investigations when corpses are in an advanced stage of decay. More data on their preimaginal development at different temperatures are necessary

Life cycle and morphology of development stages of Physocephalus dromedarii (Nematoda: Spirocercidae)

Objective: To study the development of Physocephalus dromedarii (P. dromedarii) in the final host. Methods: For this, 5 adult dromedaries were orally infected with third larval stages of P. dromedarii obtained from naturally infected scarab beetles (Scarabaeus cristatus). The camels were necropsied 14, 42, 70, 84 and 280 days after infection and their abomasi were examined for the presence of nematodes. Results: Early 4th stage larva occurred already 2 weeks after infection. They were still in the sheet of the 3rd stage larva. Six weeks after infection, the nematodes became juvenile male and female adults measuring 9 and 10 mm, respectively. Their size doubled at 10 weeks post infection and patency was reached at 12 weeks. P. dromedarii was still present in the camel that was examined 40 weeks after infection. Conclusions: As a result of experimental infection of the natural host, the determined prepatent period of P. dromedarii equalled 12 weeks

New Hepatitis E Virus Genotype in Camels, the Middle East

In a molecular epidemiology study of hepatitis E virus (HEV) in dromedaries in Dubai, United Arab Emirates, HEV was detected in fecal samples from 3 camels. Complete genome sequencing of 2 strains showed >20% overall nucleotide difference to known HEVs. Comparative genomic and phylogenetic analyses revealed a previously unrecognized HEV genotype

Novel Betacoronavirus in Dromedaries of the Middle East, 2013

In 2013, a novel betacoronavirus was identified in fecal samples from dromedaries in Dubai, United Arab Emirates. Antibodies against the recombinant nucleocapsid protein of the virus, which we named dromedary camel coronavirus (DcCoV) UAE-HKU23, were detected in 52% of 59 dromedary serum samples tested. In an analysis of 3 complete DcCoV UAE-HKU23 genomes, we identified the virus as a betacoronavirus in lineage A1. The DcCoV UAE-HKU23 genome has G+C contents; a general preference for G/C in the third position of codons; a cleavage site for spike protein; and a membrane protein of similar length to that of other betacoronavirus A1 members, to which DcCoV UAE-HKU23 is phylogenetically closely related. Along with this coronavirus, viruses of at least 8 other families have been found to infect camels. Because camels have a close association with humans, continuous surveillance should be conducted to understand the potential for virus emergence in camels and for virus transmission to humans