Date of Award

1995

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Entomology

First Advisor

Lane D. Foil

Abstract

Biotic and abiotic factors that affect the development and survival of cat flea (Ctenocephalides felis (Bouche)) life stages were studied. Adult feas maintained on an artificial host system exhibited high rates of mortality when provided with dog hair substrates washed in either hexane or soap and water. Delayed egg production for fleas provided with bovine blood containing Na Citrate concentrations $>$8 mM was observed. Fleas fed with Na Citrate concentrations $\ge$24 mM had an increase in blood consumption and mortality. Certain concentrations of testosterone fed to fleas either in steer blood or in an alternate blood meal were associated with increases in egg production. The concentration of red blood cells was shown to affect consumption and subsequent egg production. Flea larvae reared in petri dishes and test tubes readily fed upon eggs, naked prepupae, and naked pupae, but feeding upon chorions, exuvia, and other debris was not observed. Less than 5% of flea larvae maintained individually and fed feces from adult cat fleas maintained on cat hosts (CHFF) completed development to the adult stage, while essentially 100% of larvae provided with CHFF and flea eggs completed their development. Larvae reared singly in test tubes consumed an average of 20.38 $\pm$ 1.92 eggs per larva at 22.4$\sp\circ$C, 75% relative humidity compared with 26.89 $\pm$ 2.68 eggs per larva at 55% relative humidity. The LT$\sb{50}$ value for larvae provided with adult flea feces only was 29.31 d. The number of eggs or amount of yeast consumed was directly related to the percentage of larvae producing cocoons. This suggests that cocoon formation is related to larval nutrition. All larvae provided with 4 mg of yeast per larva formed cocoons while only 6.67% formed cocoons when provided with 0.25 mg of yeast per larva. First, second, and third instars did not penetrate well-constructed cocoons. Third instars readily fed upon prepupae, naked pupae, and eggs, but first and second instars did not feed on any life stage. All instars fed upon yeast. The cocoon structure was shown to provide protection from foraging flea larvae.

Pages

100

Share

COinS