BackgroundThe northern fowl mite (NFM), Ornithonyssus sylviarum, is an obligatory hematophagous ectoparasite of birds and one of the most important pests in the poultry industry on several continents. Although NFM poses a serious problem, it remains a neglected pest of poultry in China and other Asian countries. Therefore, a molecular analysis was conducted to provide baseline information on the occurrence, genetic diversity and emergence of NFM in poultry farms from China.MethodsThis study focused on morphological description and identification of adults based on electron microscopy, molecular sequencing of the mitochondrial cox1 gene and phylogenetic analysis. We have also used the DNA sequences of the cox1 gene to study the genetic diversity, population structure and demographic history. The neutrality tests were used to analyze signatures of historical demographic events.ResultsThe mites collected were identified as the northern fowl mite Ornithonyssus sylviarum based on external morphological characterization using electron microscopy. Molecular analysis using a 756-bp long partial fragment of the cox1 gene revealed 99–100% sequence identity with NFM and phylogenetic inferences showed a bootstrap value of 99% indicating a well-supported monophyletic relationship. Molecular diversity indices showed high levels of haplotype diversity dominated by private haplotypes, but low nucleotide divergence between haplotypes. The Tajima’s D test and Fu’s Fs test showed negative value, indicating deviations from neutrality and both suggested recent population expansion of mite populations supported by a star-like topology of the isolates in the network analysis. Our genetic data are consistent with a single introduction of NFM infestations and the spread of NFM infestation in Hainan poultry farms and a private haplotype dominance, which suggest that infestations are recycled within the farms and transmission routes are limited between farms.ConclusionsTo our knowledge, this is the first time a molecular report of NFM in chicken from China including other Asian countries using DNA barcoding. The findings have potential implications with respect to understanding the transmission patterns, emergence and populations trends of parasitic infestations of poultry farms that will help for setting the parameters for integrated pest management (IPM) tactics against mite infestations.

BackgroundAnaplasma marginale, Babesia bovis and Babesia bigemina cause huge economic losses to the world's cattle industry every year. At present, there are limited investigations on A. marginale, B. bovis and B. bigemina in Hainan. The purpose of this study was to investigate the infection of A.marginale, B.bovis and B.bigemina in different breeds of cattle (Leiqiong and Wagyu), buffaloes and Rhipicephalus microplus in the northern part of Hainan.MethodsIn this study, 63 R. microplus and 151 samples of bovine blood were collected from cattle in the northern part of Hainan. A. marginale, B. bovis and B. bigemina were detected by PCR and nPCR. ResultsThe results showed that the infection rates of A. marginale, B. bovis and B. bigemina in 214 samples were 10.75% (23/214), 4.21% (9/214) and 9.35% (20/214), respectively. In Leiqiong cattle, the total infection rate of several pathogens was the highest, which was 73.33% (22/30), and there was cross-infection of several pathogens, the infection rate was 46.67% (14/30). Among them, A. marginale and B. bigemina had the highest cross-infection rate, which was 26.67% (8/30). No mixed infection was detected in R. microplus, buffalo and Wagyu. Among buffalo, the infection rates of A. marginale, B. bovis and B. bigemina were 2.17% (1/46), 6.52% (3/46) and 4.35% (2/46), respectively. A. marginale infection was only found in Wagyu, with an infection rate of 2.67% (2/75). A. marginale and B. bigemina infections were found in R. microplus, but no B. bovis infection was found. ConclusionsThe results of this study provide a reference for the formulation of prevention and control strategies for A. marginale, B. bigemina and B. bovis in Hainan.