Economic evaluation and efficacy of strategic-selective treatment of gastrointestinal parasites in dairy calves

Cryptosporidiosis and Giardiasis in Buffaloes (Bubalus bubalis)

Cryptosporidium spp. and Giardia duodenalis infect the gastrointestinal tracts of animals and humans. Both parasite groups are distributed worldwide and cause significant economic losses in animal productivity. Infected hosts presenting with and without clinical manifestations can eliminate infective forms of these protozoa, which are particularly important to One Health. Compared to the published research on cattle, relatively few studies have examined the epidemiology of cryptosporidiosis and giardiasis in buffaloes. This short review describes the global occurrence of Cryptosporidium spp. and G. duodenalis in buffaloes, including the molecular techniques employed for the identification of species/assemblages and genotypes of these protozoa. Genetic analyses of isolates of G. duodenalis and Cryptosporidium spp. from various sources (environmental, animal, and human) have been performed to investigate their epidemiology. In buffaloes, the species Cryptosporidium parvum, Cryptosporidium ryanae, Cryptosporidium bovis, and Cryptosporidium suis-like have been characterized, as well as assemblages A and E of G. duodenalis. We demonstrate that buffaloes can be infected by species of Cryptosporidium spp. and G. duodenalis assemblages with zoonotic potential. Epidemiological studies that utilize molecular biology techniques represent an important resource for efforts to control and prevent the spread of these protozoans.

First description of Giardia duodenalis in buffalo calves (Bubalus bubalis) in southwest region of São Paulo State, Brazil

We performed molecular characterization of Giardia duodenalis in buffalo calves from the Southwest region of São Paulo State, Brazil. A total of 183 fecal samples of Murrah breed buffaloes up to six months of age were collected. We examined these samples by the polymerase chain reaction (PCR) targeting the small-subunit ribosomal RNA gene and positive samples were characterized using additional PCR assays targeting a portion of the beta-giardin, the glutamate dehydrogenase and the triose-phosphate isomerase genes. Based on the SSU rRNA nPCR, the presence of G. duodenalis was confirmed in 12 (6.56%) of fecal samples, of these, five, four and three samples were positive for the tpi, bg and gdh genes, respectively. Assemblage identification by sequencing was successful in 6 of 12 samples and sequence analysis showed 100% genetic similarity with G. duodenalis assemblage E. This observation represents the first detection of G. duodenalis assemblage E in buffaloes calves in Brazil.

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First study of Giardia in fecal samples of buffalo calves from Brazil.

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Detection of Giardia in buffaloes by nested PCR using four genetic markers.

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Phylogenetic analysis identified Giardia duodenalis assemblage E.