Molecular detection and characterization of Hepatozoon canis in stray dogs from Cuba.

Canine hepatozoonosis caused by Hepatozoon canis is a worldwide distributed tick-borne disease of domestic and wild canids that is transmitted by ingestion of Rhipicephalus sanguineus sensu lato (s.l.) ticks. The present study was aimed to determine the prevalence of Hepatozoon infections in 80 stray dogs from Havana Province in Cuba, and to confirm the species identity and phylogenetic relationships of the causative agent. Samples were screened by microscopical examination of thin blood smears for the presence of Hepatozoon spp. gamonts and by genus-specific SYBR green-based real-time PCR assay targeting the 18S rRNA gene. Direct microscopy examination revealed Hepatozoon gamonts in the peripheral blood of 8 dogs (10.0%; 95% CI: 4.80-18.0%), while 38 animals (47.5%; 95% CI: 36.8-58.4%) were PCR-positive, including all microscopically positive dogs. Hence, the agreement between the two detection methods was 'poor' (κ = 0.20). Hematological parameters did not differ significantly between PCR-positive and PCR-negative dogs (p > 0.05). The DNA sequences of the 18S rRNA gene of the Hepatozoon spp. from Cuban dogs showed a nucleotide identity >99% with those of 18S rRNA sequences of Hepatozoon canis isolates from Czech Republic, Brazil and Spain. Phylogenetic analysis revealed that obtained sequences clustered within the Hepatozoon canis clade, different from the Hepatozoon felis or Hepatozoon americanum clades. The present study represents the first molecular characterization of Hepatozoon canis in stray dogs within Cuba.

First molecular evidence of bovine hemoplasma species (Mycoplasma spp.) in water buffalo and dairy cattle herds in Cuba.

BACKGROUND: Hemotropic mycoplasmas (aka hemoplasmas) are small bacteria which cause infectious anemia in several mammalian species including humans. Information on hemoplasma infections in Cuban bovines remains scarce and no studies applying molecular methods have been performed so far. The aim of the present study was to utilize real-time PCR and sequence analysis to investigate dairy cattle and buffalo from Cuba for the presence of bovine hemoplasma species. RESULTS: A total of 80 blood samples from 39 buffalo and 41 dairy cattle were investigated for the presence of Mycoplasma wenyonii and "Candidatus Mycoplasma haemobos" using two species-specific real-time TaqMan PCR assays. PCR results revealed overall 53 (66.2%; 95% CI: 55.3-75.7%) positive animals for M. wenyonii and 33 (41.2%; 95% CI: 31.1-52.2%) for "Ca. M. haemobos"; the latter were all co-infections with M. wenyonii. The sample prevalences were similar in cattle and buffalo. Based on the sequence analysis of the nearly full-length 16S rRNA gene from two cattle and two buffalo, the presence of M. wenyonii and "Ca. M. haemobos" was confirmed. Statistical analysis revealed that buffalo and cattle one year of age or older were more frequently infected with M. wenyonii or "Ca. M. haemobos" than younger animals. PCR-positivity was not associated with anemia; however, the infection stage was unknown (acute infection versus chronic carriers). CONCLUSIONS: The high occurrence of bovine hemoplasma infections in buffalo and dairy cattle may have a significant impact on Cuban livestock production. To the best of our knowledge, this is the first molecular evidence of bovine hemoplasma species infection in dairy cattle and buffalo from Cuba and the Caribbean.

First molecular evidence of Babesia caballi and Theileria equi infections in horses in Cuba.

Equine piroplasmosis is a disease of Equidae, including horses, donkeys, mules, and zebras, caused by either Theileria equi or Babesia caballi. This disease represents a serious problem for the horse industry and its control is critical for the international trade of horses. The objective of the present study was to detect B. caballi and T. equi infections in horses reared in western Cuba. Blood samples from 100 horses were tested for the presence of piroplasms by using Giemsa-stained blood smears and nested PCR (nPCR) assays targeting merozoite antigen genes of B. caballi (bc48) and T. equi (ema-1). All animals were inspected for the detection of tick infestation and tick specimens were collected for species identification. Erythrocyte inclusions were observed in 13 (13%) of the analyzed samples. nPCR analysis showed that 25 (25%) samples were positive for B. caballi, 73 (73%) for T. equi, and 20 (20%) showed dual infections. Only one tick species was found infesting horses, Dermacentor nitens. In addition, three nearly full-length sequences of T. equi 18S rRNA gene were obtained and subjected to phylogenetic analyses. This study reports a high prevalence of T. equi and B. caballi single and coinfections in horses in western Cuba. Molecular analysis of the 18S rRNA gene of T. equi suggested that different genotypes of this hemoparasite circulate in Cuba. To the best of our knowledge, this is the first report describing the molecular detection of B. caballi and T. equi in horses in Cuba.

Melhoria da eficiência ruminal: inoculação de bactérias

O CH4 é um dos coprodutos da fermentação da dieta no estômago desses animais

Melhoria da eficiência ruminal: inoculação de bactérias

O CH4 é um dos coprodutos da fermentação da dieta no estômago desses animais