Seasonal abundance and activity of the tick Dermacentor silvarum in northern China

Abstract

Studies on the seasonal abundance and activity of larvae, nymphs and adults of Dermacentor silvarum (Ixodida: Ixodidae), both on and off the host, were carried out over a 2-year period from February 2008 to January 2010 in northern China. During the study period, feeding ticks were removed weekly from domestic sheep and free-living ticks were collected weekly by flag-dragging in four different habitat types. Rodents were captured and inspected for immature ticks from June to September 2008. The results of this study suggest that the ticks mainly reside in shrubs and complete only one generation per year with sequential seasonal distribution and little overlap between the activity of the larvae and nymphs. Adults were most prevalent from late February to late May and peaked in number in mid-April. Larvae were found from early June to early September and peaked in number in mid-July. Nymphs were mainly distributed from late June to late September and peaked in mid-August. Adult and nymphal D. silvarum were found primarily on the ears of sheep, but no larvae were found on sheep. Additionally, an overwintering male adult population was detected on sheep after October, but no free-living adults were found by dragging.

Abundance and seasonal activity of Haemaphysalis concinna (Acari: Ixodidae) at the border between China and Russia in Northern Inner Mongolia, China

“…Two hundred live traps with the measure of 30 × 15 × 10 cm (Sichuan Shujile Trading Co., Chengdu, Sichuan, China) were placed along five lines covering an area of about 10000 m 2 . The traps, set up at around 18:00 h, were checked the following morning at around 07:00 h, as described previously [ 20 ]. Trapped rodents were anaesthetized by injection with 2 % pelltobarbitalum natricum (Tianjin Yongda Chemical Reagent Co., Tianjin, China) at a dose of 0.2 ml/100 g per bodyweight and identified for species according to a previous report [ 21 ].…”

“…The rodents were released back to the wild in their field of capture after tick removal. The prevalence of infestation was defined as the number of infested rodents divided by the total number of the host species examined, and the mean intensity represents the total number of ticks collected from each rodent species divided by the total number of infested hosts [ 20 ].…”

Distribution of Dermacentor silvarum and Associated Pathogens: Meta-Analysis of Global Published Data and a Field Survey in China

“…Dermacentor silvarum , a species of hard ticks, is widely distributed in North China, Russia, and Mongolia [ 7 , 8 , 9 ]. They have a hard scutum, the cornua of basis capituli is longer and pointy, and the length is nearly equal to the base width.…”

Vectors of disease at the northern distribution limit of the genus Dermacentor in Eurasia: D. reticulatus and D. silvarum

“…Dermacentor silvarum (formerly sometimes referred to as D. asiaticus) is widely distributed in taiga forests in south-eastern Russia (Kulik and Vinokurova 1983a), northern Mongolia (Kiefer et al 2010), and northeastern and central China (Yu et al 2011). It can also be found in big cities like the Chinese capital Beijing (Li et al 2002;Guo et al 2009).…”

“…2010 ), and northeastern and central China (Yu et al. 2011 ). It can also be found in big cities like the Chinese capital Beijing (Li et al.…”