FAO - Brazilian Sub- Centers. Report on agreement with the VPRG and activities developed during J.R.Martins IPVDF

Sub-Center II FMU – São Paulo Coordinator: Gustavo Sabatini Main Activity: In vitro tests aiming to show behaviour of 2 strains (Piquete e Guaratinguetá) with characteristic of ivermectin resistance in the field.

Table 1. Results from the larval immersion tests (LIT), using commercial ivermectin (1%, injectable) in a 1% ethanol and 2% Triton X-100 solution, of field strains and susceptible control (“Porto Alegre” strain). SampleN a SlopeLC 50 b (CL 95%) c (ppm) Control ( ) Pop ( ) Pop ( ) Pop ( ) Pop ( ) Pop ( ) a N is the number of replicates of each test. b LC 50 is the lethal concentration for 50% c CL is the confidence limits, given in brackets after the LC 50. Sub-Center FMU - USP

Figure 1. Comparison of dose-mortality curves of field strains of Piquete, Sao Paulo, Brazil. Sub-Center FMU - SP

Figure 2. Comparison of dose-mortality curves of field strains of Guaratingueta, Sao Paulo, Brazil. Sub-Center FMU - SP

Sub-Center I - IPVDF – RS Coordinator: João Ricardo Martins Main activities: *Stall tests in order to confirm suspect of ML resistance in the field; *Monitoring resistance to CE compounds; *Evaluate new acaricides/formulations *Extension activities

In 2005: At least 2 strong field evidence of ivermectin resistance -strain “São João”, municipality of Rio Pardo, RS -strain “Bárbara”, municipality of São Jerônimo, RS Sub-Center IPVDF – RS Coordinator: João Ricardo Martins Common points: -no dip tank in the farm -intensive use of LM

Strain São João: (some aspects) R to amitraz, SP, OP S to mixtures (starting on july/2005) Intensive use of generic LMs – 5 to 7 treatments a year, depending on animal category *Calves are treated after born (1st day) Strain is presently kept in the laboratory

Strain “Bárbara ” Use of mechanical aspersion R to amitraz (jun/2005), SP & OP S to mixtures (since jun/2005 in use) All calves are treated after borning with LM and then, at 3-4 months, weaning, every changing of paddock, *average 3 to 4 treatments a year, since 1995 (plus spray for horn-fly)

Test with tick larvae

Tests with larvae: Characterization of strains and monitoring of resistance

Teste com larvas: exposição as diferentes concentrações

Teste de estábulo: -boxes individuais para bovinos

Stall Test: -calves remain in appropriate floor for tick tick collection

Infestation: 250 mg of larvae (5000 larvae)

Teste de estábulo: Carrapatos são colhidos em peneiras com malha apropriada

RESULTS OF ADULT IMERSION TESTS 2005 Amitraz Mixture SP+ OP Suscetible 12 (41,3%) 26 (92,8%) Resistents 17 (58,6%) 02 (7,1%) Total 29 28

Aspects of Amitraz resistance in Rio Grande do Sul: -slow dissemination -cases of reversibility

Amitraz Resistance in 2005 First Report in RS: 1994

Sub-Center III –Embrapa/CNPGC Coordinator – Renato Andreotti

Proposal of activities for the Sub-Centers in conjunction with the VPRG for J/F/MA/M/JJ/A/SO/N/D Sub-Center I IPVDF/FEPA GRO -Monitoring R & to establish a data bank 1 -Maintenance & actualization of a “site” on cattle tick 2 -Extension activities (talks, leaflets) 3 -Maintenance of R reference strain 4 > -same -training course on diagnosis of tick R (in cooperation with Uruguay) -create a permanent virtual forum of discussion on tick control -same -Technical meeting (?) Sub-Center II FMU/SP -Monitoring R to LMs and to publish -training course on -Technical meeting (?) Sub-Center III Embrapa- CNPGC -Hold a sub- center/VPRG meeting in order to discuss & planning activities --training course on -Technical meeting (?) *All subcenters should interact closely with the FAO Reference Center at CIVET Miguel Rubiño, Montevidéo, Uruguay (exchanging information, training courses, tick strains, impregnated papers, chemicals, etc.).