a study of the diapausing behaviour of rhipicephalus appendiculatus and r. zambeziensis under quasi-natural conditions in zambia.the diapausing behaviour of rhipicephalus appendiculatus was studied under quasi-natural conditions in the eastern province of zambia. newly-moulted adults of ticks indigenous to the study area entered a behavioural diapause when exposed to daylengths below a critical photoperiod, provisionally a daylength between 11 h 20 min and 11 h 45 min. in the eastern province of zambia the diapause was apparently not terminated by a long-day signal, but by a weakening of the photoperiodic maintenance of t ...19957548950
diapause induction in adults of three rhipicephalus appendiculatus stocks.newly-moulted adults of three rhipicephalus appendiculatus stocks, originating from kenya, zambia and zimbabwe, were kept in different photoperiods (12h:12h, 13h:11h and 14h:10h light:dark). the stock originating from kenya showed almost no behavioural diapause in any of these day lengths, whereas virtually all individuals of the zimbabwean stock entered a behavioural diapause irrespective of day length. adults from the eastern province of zambia, a transition zone between the multivoltine pheno ...199910737730
immunisation against theileria parva in eastern zambia: influence of maternal antibodies and demonstration of the carrier status.immunisation of calves by the infection and treatment method (i & t) has been extensively used in the eastern province of zambia to control east coast fever (ecf), a protozoan tick-borne disease. this paper presents the results of a field longitudinal study, which included a total of 148 angoni calves. after immunisation against ecf, they were monitored for a full rainy season, coinciding with the main peak of activity of the vector of theileria parva, the tick rhipicephalus appendiculatus. dysi ...200212446089
further evidence for geographic differentiation in r. appendiculatus (acari: ixodidae) from eastern and southern provinces of zambia.studies in the biology, ecology and behaviour of r. appendiculatus in zambia have shown considerable variation within and between populations often associated with their geographical origin. we studied variation in the mitochondrial coi (mtcoi) gene of adult r. appendiculatus ticks originating from the eastern and southern provinces of zambia. rhipicephalus appendiculatus ticks from the two provinces were placed into two groups on the mtcoi sequence data tree. one group comprised all haplotypes ...200717340215
ecology and phenology of ticks in zambia: seasonal dynamics on cattle.a study of the seasonality and infestation rates of ticks was carried out in 11 cattle herds in different ecological habitats in zambia between 1980 and 1982. wherever possible supplementary data were obtained from opportunistic collections from cattle and other hosts. analysis of over 1000 tick collections from cattle indicated that infestation rates of the most important species, amblyomma variegatum and rhipicephalus appendiculatus vary in different ecological habitats: (i) in western provinc ...19863451861
a survey of the ixodid ticks parasitising cattle in the eastern province of zambia.the results of tick surveys carried out in the eastern province of zambia between december 1982 and february 1996 were principally in agreement with the findings of earlier surveys conducted during the period 1965-72. boophilus decoloratus has almost been replaced by boophilus microplus. hyalomma truncatum was found in small numbers throughout the province and hyalomma marginatum rufipes was only rarely encountered in collections made from cattle. rhipicephalus evertsi evertsi was largely confin ...19989737594
spatial and temporal variation in rhipicephalus appendiculatus size in eastern zambia.the size of rhipicephalus appendiculatus collected at different altitudes in the eastern province of zambia between february 1985 and may 1986 and between october 1994 and december 1996 showed distinct variation dependent on altitude and season. the ticks were smallest during the dry season and at the start of the rains, and specimens were larger as the rainy season progressed. second-generation adults where on average smaller than first-generation ticks. at higher altitudes, where a one-generat ...199910540311
the current epidemiological status of bovine theileriosis in eastern zambia.results of a longitudinal study conducted in the eastern province of zambia from 1994 to 1997 indicate that it is doubtful whether a state of endemic stability of east coast fever (ecf) can be reached in the near future. even in endemic areas, the mortality of theileria parva infections is still estimated above 50%. the main factors limiting progress towards endemic stability are high innate susceptibility of the zebu cattle, the virulence of the parasite and the climate. the unimodal rainfall p ...199910540309
re-assessment of tick control after immunization against east coast fever in the eastern province of zambia.east coast fever, caused by the protozoon theileria parva and transmitted by the ixodid tick rhipicephalus appendiculatus is one of the most important cattle diseases in east and central africa, responsible for considerable direct losses and necessitating expensive control measures. traditionally, the disease was controlled by means of intensive tick control. the belgian animal disease control project was requested to study the disease epizootiology and vector ecology in order to formulate and i ...19911793284
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