Acquisition and transmission of Hepatozoon canis (Apicomplexa: Hepatozoidae) by the tick Amblyomma ovale (Acari: Ixodidae)

Abstract

The present study aimed to evaluate under controlled conditions the acquisition of Hepatozoon canis by Amblyomma ovale after feeding on infected dogs, and the subsequent induction of infection in uninfected dogs that ingested the experimentally infected ticks. Two H. canis naturally infected dogs were infested with A. ovale adult ticks derived from an uninfected laboratory tick colony. After feeding, two A. ovale females presented H. canis oocysts in the hemolymph at the first and fourth days after removal of ticks from dogs. The oocysts had an average size of 244.34 microm x 255.46 microm. Three uninfected dogs were fed with ticks previously fed on the infected dogs. Only one dog became infected 32 days after oral inoculation, presenting circulating gametocytes, parasitemia less than 1%, and positive PCR confirmed to be H. canis by DNA sequencing. The results obtained indicated A. ovale ticks as potential vector of H. canis in rural areas of Brazil.

Molecular diagnosis of Hepatozoon canis in symptomatic dogs in the city of Goiania, Goiás, Brazil

“…In the present study, the species R. sanguineus was only identified in one of the dogs evaluated, and no other tick species were identified. This is not a conclusive finding with regard to participation of the species R. sanguineus in the transmission of hepatozoonosis, even though this possibility was previously pointed out by Forlano et al (2005), Baneth et al (2007), and Rubini et al (2009).…”

“…This has motivated use of molecular biology techniques in studies on the etiology and epidemiology of canine hepatozoonosis. Several authors like Inokuma et al (2002), Forlano et al (2005), Spolidorio et al (2009) have used PCR to identify these agents. As already mentioned, PCR reactions performed on two samples obtained in this study confirmed the presence of Hepatozoon sp.…”

“…In Brazil, different studies involving molecular analyses have confirmed the presence of H. canis in naturally infected dogs (Forlano et al, 2005;Spolidorio et al, 2009), cats (Perez et al, 2004) and wild felines (Metzger et al, 2008).…”

“…However, in Brazil, only Amblyomma ovale has been confirmed as a vector species for this in experimental studies (Forlano et al 2005;Rubini et al 2009). The infection in dogs due to H. canis can range from subclinical, with low-level parasitemia, to serious disease that threatens the animal's life, especially in young or immunosuppressed individuals (Hervas et al, 1995).…”

Ectoparasitos Em Cães De Áreas Peri-Rurais Do Município De Rio Branco, Acre, Amazônia Ocidental

“…O parasitismo de Amblyomma ovale nos cães de áreas peri-rurais do munícipio de Rio Branco, AC, os predispõem a serem acometidos por hepatozoonose canina uma vez que Rubini et al (2009) afirmam que A. ovale é o vetor potencial de hepazoonose em cães rurais. Além do mais, Sousa et al (2017) verificaram a alta prevalência de Hepatozoon entre carnívoros amostrados no Pantanal e a ocorrência de infestação de A. ovali em animais silvestres.…”