Morphometrics of Amblyomma mixtum in the State of Veracruz, Mexico

The tick Amblyomma mixtum is an ectoparasite of veterinary and public health importance because of its role as a vector of zoonotic pathogens. However, little is known about A. mixtum intraspecific variability and if morphological differentiation exists between populations across its geographic range. This study aimed to determine by electron microscopy the morphological variability of A. mixtum populations in the state of Veracruz, which has a large livestock population among states in Mexico. Forty male and 40 female A. mixtum collected from the 10 natural regions of Veracruz state were analyzed microscopically to accomplish main component analysis for each sex. Clusters were calculated with the out-tree method and a dendrogram produced to group the specimens according to their morphometric characteristics. Using 10 main components, 77% of the morphological variation of the ticks was explained. This is a reflection of scarce intraspecific variation between females. The dendogram for females grouped six clusters of specimens with similar characteristics. Morphometric variability in males was described using eight main components. Limited intraspecific variation was also observed between males. In males, the dendogram yielded six groups with similar morphometric characteristics. Morphometric analyses confirmed that the only species from the Amblyomma cajennense complex that are parasites to livestock in Veracruz state is A. mixtum. The eryxenous nature of A. mixtum combined with the frequent movement of livestock hosts may contribute to the apparent homogeneous phenotype of this tick species in Mexico

Epidemiological assessment of intestinal parasitic infections in dogs at animal shelter in Veracruz, Mexico

Objective: To determine the prevalence of infection with intestinal parasites in 101 dogs in an animal shelter in Veracruz, Mexico, and investigate whether any general characteristics of the dogs were associated with infections. Methods: Parasitological examination of fecal samples from the dogs was performed by means of centrifuge-flotation using Sheather's sucrose and zinc sulfate flotation media. In addition, hematocrit was determined in each canine blood sample. Results: Intestinal parasites were found in 99 (98.0%) of the 101 dogs studied. About five different intestinal parasites were identified: Ancylostoma caninum in 89 dogs (88.1%), Giardia canis in 46 (45.5%), Uncinaria stenocephala in 43 (42.6%), Trichuris vulpis in 19 (18.8%) and Strongyloides canis in 16 (15.8%). Multivariate analysis showed: 1) Giardia infection was associated with young age and mixed breed; 2) Ancylostoma was associated with young age and no rabies vaccination; and 3) Strongyloides was associated with no rabies vaccination. Uncinaria and Trichuris infections were not associated with the variables assessed. Conclusions: A high prevalence of intestinal parasites was found in the dogs studied. This suggests that the environment is highly contaminated with intestinal parasites. Preventive and therapeutic measures should be taken against infection with intestinal parasites in dogs in this region

Occurrence of Amblyomma mixtum on the water buffalo (Bubalus bubalis) in Mexico

The water buffalo (Bubalus bubalis) is an Asian species of bovine that was introduced in Mexico in 1992 as an alternative for milk and meat production. To date, no surveys have been conducted to identify ticks acquired by water buffaloes since their arrival in the country. Here we report, for the first time, the presence of Amblyomma mixtum, a neotropical tick in the Amblyomma cajennense complex, found on water buffaloes from Mexico and discuss its possible implications in veterinary public health for the region. Keywords: New host, Amblyomma mixtum, Mexico, Water buffal