Determination of Acaricide Resistance in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) Field Populations of Argentina, South Africa, and Australia With the Larval Tarsal Test

Infestations with ticks have an important economic impact on the cattle industry worldwide and resistance to acaricides has become a widespread phenomenon. To optimize their treatment strategy, farmers need to know if and against which classes potential acaricide-resistance does occur. Bioassays are used to assess the resistance level and pattern of Rhipicephalus (Boophilus) microplus populations. The objective of the current study was to assess the susceptibility of field populations originating from Argentina (8), South Africa (3), and Australia (2) using the Larval Tarsal Test. Nine acaricidal compounds from five major classes were tested: organosphosphates, synthetic pyrethroids (SP), macrocyclic lactones, phenylpyrazols, and amidines. The resistance ratios at concentrations inducing 50 and 90% mortality were used to detect established and emerging resistance. This study confirmed the newly reported presence of amitraz resistance in populations from Argentina. In addition, resistance to SP appeared to be widespread (88%) in the Argentinean farms, which had been selected based on the observation of lack of treatment efficacy by farmers. In South Africa one of the three populations was found to be resistant to SP and to a phenylpyrazol compound (pyriprol). Furthermore, resistance to organosphosphates and SP was observed in Australia. Finally, the Larval Tarsal Test proved to be a suitable test to evaluate the susceptibility of R. microplus field populations to the most relevant acaricidal classe

Tick-borne pathogens in the blood of wild and domestic ungulates in South Africa: interplay of game and livestock

Published ArticleWe screened for tick-borne pathogens blood samples from 181 wild and domestic ungulates belonging to 18 host species in 4 South African Provinces. Polymerase chain reaction followed by reverse line blotting and sequencing allowed detecting 16 tick-borne pathogen species belonging to the genera Babesia, Theileria, Anaplasma, and Ehrlichia. Ten pathogen species were involved in 29 new host–pathogen combinations. Most infections (77.9%) involved more than one pathogen species. Principal component analysis (PCA) assigned the 163 infections, identified to species level, to 4 groups. Three groups were associated with sheep, cattle, and horse and their respective wild counterparts. Each group was characterised by high homogeneity in pathogen assemblage and host phylogenetic status. These groups characterised the most privileged transmission routes between and among wild and domestic ungulates. The 4th group showed high heterogeneity in pathogen assemblage and host phylogenetic status. This group seems to indicate frequent spill over events in impala of pathogens that usually circulate among cattle- or sheep-related species. Within 6 localities, we sampled an equal number of wild and domestic animals (n = 128). On this dataset once having controlled for the significant variation among localities, the infection prevalence and intensity of infection did not differ significantly between wild and domestic hosts. This suggests that both animal types, domestic and wild hosts, could act as evenly efficient sources of infection for themselves and for each other. Overall, this study shed new light on the pathogen circulation naturally achieved at the interplay between wild and domestic ungulates

Analyse der Belastungs- und Beanspruchungssituation beim Arbeiten mit handgefuehrten, einachsigen Arbeitsgeraeten fuer die Bodenbearbeitung und Ableitung von technischen und organisatorischen Gestaltungsmassnahmen Abschlussbericht

The project under review was dedicated to the description of critical loads and stresses on professional gardeners and hobby gardeners using hand-operated rotary cultivators. The load and stress situations were assessed as a function of factors related to the implements and to the work which is done using them. While loads were measured and evaluated by Fraunhofer-Institut fuer Arbeitswirtschaft und Organisation (IAO), Stuttgart, stresses were analyzed by the Department of Ergonomics at the Hohenheim University. Physiological stress analyses were competed questioning the users about their subjective stress sensations. Technical measures for reduction of the loads and stresses on users were developed on the basis of the evaluated data. Weak points as regards safe and ergonomic handling were analyzed in addition. The detected design deficiencies lead to measures which reduce mental stresses and increase safety while working. (orig.)SIGLEAvailable from TIB Hannover: F94B1048+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman