Factors influencing the life cycle of ctenocephalides spp.

[摘要] English: The behaviour and survival of C. felis are highly dependent on biotic and abiotic factorsin the environment and therefore developmental and nutritional requirements demand thateggs must be laid in a environment which provides the suitable microhabitat for C. felisdevelopment. Since eggs and larval stages of the cat flea cannot survive majorfluctuations in temperature and humidity, sites for development are usually limited. Itwas found that eggs desiccated at low relative humidities and hatched faster at highertemperatures. The percentage adult emergence also depended on the type of rearingmedium on which the larvae fed. The duration of the larval stage increased with adecrease in temperature and eggs exposed to high relative humidity resulted in largerlarvae. However, Ci felis populations survive because of a large reproductive capacity ofthe female and the ability of the pupal stage to survive environmental fluctuations. Thepupa is the immature stage that is most resistant to desiccation and it is during this stagethat C. felis is able to prolong its life cycle in order to survive unfavourable conditions.The fully developed adult flea can remain quiescent within the cocoon, presumablyawaiting proper stimuli for emergence. Optimal conditions for C. felis development werefound to be 25±2°C and 75±2% relative humidity.In spite of the many similarities between C. felis and C. canis, a comparative studyshowed conspicuous differences in the micro-morphology of these two species.Although only small differences were found in the biology of C. felis and C. canis, thehost specificity and geographical distribution of the two species varied greatly. C. felis isthe most common flea species to attack domestic pets, C. canis is more restricted indistribution.Apart from its association with various diseases and flea allergy dermatitis (FAD), C.felis can also serve as the intermediate host for the dog tapeworm, D. caninum. C. felisbecome infected with the parasite during any period of the larval stage when larvae ingestthe eggs of D. caninum. Although it was found that D. caninum were only slightlyharmful to its intermediate host under optimal conditions for C. felis development, thenegative effect on the intermediate host increased with an increase in the intensity ofinfection.

[发布机构] University of the Free State