Detection of Anaplasma marginale DNA in larvae of Boophilus microplus ticks by polymerase chain reaction.
Boophilus microplus larvae from two different sources were used for the detection of Anaplasma marginale DNA: larvae A, which were collected from a pasture of an endemic farm, and larvae B, which originated from engorged female ticks fed on calves with no clinical signs of disease and with low rickettsemia (approximately 0.01 to 1.0%). Larvae A were collected monthly, from January to May in 2001. Two hundred engorged female ticks fed on calves that provided larvae B were divided into groups of 10 and kept in a controlled environment at either 18 degrees C or 28 degrees C. Fifty larvae were used from each sample for DNA extraction, and 5 muL of DNA were submitted to amplification of the sequence of msp5 gene of A. marginale by polymerase chain reaction (PCR). Seven out of 50 samples of larvae A (14%) were positive for the presence of DNA of A. marginale showing amplified product of 457 bp. Ten out of 91 samples of larvae B (11%) kept at 18 degrees C were positive, and all larvae B at 28 degrees C were negative. Thus, this study confirmed the presence of A. marginale DNA in B. microplus larvae by PCR. The EcoRI restriction enzyme analysis confirmed the specificity of the amplicon, which resulted in two fragments: 265 bp and 192 bp. The sequencing analysis of the amplicon from larvae demonstrated 98% homology with the msp5 sequence from Florida A. marginale strain.
Shimada
Márcia Kiyoe
MK
Departamento Med. Vet. Preventiva, CCA, Universidade Estadual de Londrina, Campus Universitário, Londrina, PR, Brazil.
Yamamura
Milton Hissashi
MH
Kawasaki
Paula Miyuki
PM
Tamekuni
Kátia
K
Igarashi
Michelle
M
Vidotto
Odilon
O
Vidotto
Marilda Carlos
MC
D042322:Anaplasma marginale / Q000235:genetics* / Q000472:pathogenicity*; D000712:Anaplasmosis / Q000635:transmission; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002418:Cattle Diseases; D004269:DNA, Bacterial / Q000032:analysis*; D007814:Larva; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013987:Ticks / Q000382:microbiology*
D004269:DNA, Bacterial