Franco Sandoval, Luz Ofelia; Caballero García, María de Lourdes; Reveles Hernández, Rosa Gabriela; Moreno García, María Alejandra; Jiménez Cardoso, Enedina
Resumen:
Four different isolates of Trichinella spp. (Z1, Z2, Z3, and Z4) obtained from the skeletal muscle of street
dogs in the state of Zacatecas, Mexico were serial passaged in Wistar rats; infective larvae from the skeletal
muscle of the rats were collected and frozen in liquid nitrogen. After centrifugation, DNA was
extracted and the 5SRNAr and IsRNAr genes were amplified. The isolates were identified by the size of
the amplified products from the 5SRNAr and IsRNAr genes (750 and 290 bp, respectively). The amplicons
obtained by PCR were sequenced, aligned, and compared to the reference strain Trichinella spiralis MSUS/
MEX/91//EM isolated from pigs.
Based on our results, we determined that the Trichinella isolates from canine (Z1–Z4) belonged to the T.
spiralis species and had 83% identity with the reference strain. The phylogenetic tree constructed from the
sequences showed differences between the isolates from pig and dog. These genetic differences may be
related to the immune response of the host or the pathogenicity of the isolates. Therefore, these findings
have important epidemiological and public health implications.