Assessment of fungal isolates for development of a myco-acaricide for cattle tick control.

Entomopathogenic fungal isolates of Arachnid origin were assessed for their ability to produce mortality and inhibit egg hatching in Boophilus microplus with the aim of selecting an isolate for development into a myco-acaricide for control of cattle ticks. The ability of the most promising isolate to target developmental stages of more than one tick species and the optimum concentration of fungal inoculum to be used for future studies were determined. Metarhizium anisopliae was the most pathogenic of the three fungal species tested on B. microplus, producing shorter average survival times (ASTs) for engorged adults (AST = 5.2 +/- 0.1 days) and larvae (AST = 9.3 +/- 0.4 days), and a longer average hatching times (AHT; AHT = 19.8 +/- 0.5 days) in comparison to Simplicillium lamellicola and Paecilomyces farinosus. In comparative studies on two tick species with similar life cycles, M. anisopliae produced a shorter AST in engorged adult B. microplus (AST = 8.8 +/- 0.3 days) than Rhipicephalus sanguineus (AST = 10.3 +/- 0.3 days). M. anisopliae was pathogenic to larvae of B. microplus (AST = 7.7 +/- 0.4 days), however, had no effect on larvae of R. sanguineus (AST = 14.6 +/- 0.3 days) as the AST of this treatment was similar to its untreated control (AST = 14.1 +/- 0.4 days). M. anisopliae lengthened the AHTs in both B. microplus (AHT = 16.4 +/- 0.3 days) and R. sanguineus (AHT = 16.7 +/- 0.3 days) in comparison to the controls. The ASTs of engorged adult B. microplus treated with M. anisopliae shortened as the concentration was increased from 1 x 10(7) to 5 x 10(8) conidia/ mL. A further increase in concentration, 1 x 10(9) conidia/mL (AST = 10.2 +/- 0.4 days) did not shorten or lengthen the AST in comparison to 5 x 10(8) conidia/mL (AST = 9.4 +/- 0.3 days).

Eradication of the tropical bont tick in the Caribbean: is the Caribbean amblyomma program in a crisis?

The progress and problems in the Caribbean Amblyomma Program (CAP) are reviewed since its inception in 1995. During 1998, there were funding and administrative management problems. USDA resolved the acute funding crisis, and after three years of negotiation, the CAP has now secured an additional euro 1.5 million from the European Community. Changes in administration in 1998 included the withdrawal of IICA from the program, and the transition during the decentralization of administrative and financial management from FAO headquarters to the Regional Office for Latin America and the Caribbean, based in Chile. A general overview of technical progress and one case study, St. Kitts, is presented. One major concern that emerged during 2000 is that the elimination of the small remaining tropical bont tick (TBT) "hot spots" in both St. Kitts and St. Lucia remained elusive. Why is this so? Egrets? Alternative residual hosts? Or is it fatigue in both technical and administrative management functions? Of even greater concern is the finding of two, apparently new, foci in St. Croix (USVI) in the north and St. Vincent in the south. A critical overview of the program has identified one major remaining constraint-an appropriate management support function at both regional and, in some countries, at the national level. A proposal for a revised management strategy, coupled with the identification of a future strategy to succeed the CAP, namely a Caribbean Animal Resources Management (CARM) Program.