Cryptosporidium spp. and Giardia sp. in aquatic mammals in northern and northeastern Brazil

Endoparasite survey in Amazonian manatees (Trichechus inunguis) under rehabilitation in the Peruvian Amazon

Manatee populations are declining worldwide, and all currently existing species are considered vulnerable by the IUCN. The most common problems during nurturing young Amazonian manatees, Trichechus inunguis, in rescue centres are of gastrointestinal nature leading to inappetence, diarrhoea, cachexia and even death. Endoparasites play an important role in the well-being of wildlife in captivity as well as in the wild, though information about relevant protozoan and metazoan endoparasites in Amazonian manatees is still scarce. Therefore, this study aimed to find endoparasites in T. inunguis by analyzing faecal samples from 23 Amazonian manatees which were kept in rescue centres in the Peruvian Amazon. The samples were screened for protozoan and metazoan parasites using coproscopical analysis and molecular tools. Out of twenty juvenile animals eleven were positive for at least one Eimeriidae. Two morphologically different, not yet genetically described Eimeria species were identified. One of them seems to be Eimeria trichechi which has only been described once in 1984 in Amazonian manatees from Brazil. It was not found to lead to clinical symptoms of coccidiosis in this study. The second, Eimeria sp. Type B was associated with clinical coccidiosis in a young Amazonian manatee, which showed gastrointestinal symptoms including diarrhoea, inappetence and cachexia. No other protozoan or metazoan parasite were detected in any of the samples. The present study is the first to investigate endoparasites in Amazonian manatees using molecular tools and is the first to identify an Eimeria species that could be associated with clinical symptoms in T. inunguis. With information from our study rescue centres can improve monitoring of parasites more effectively to reduce morbidity and mortality rates among rehabilitated manatees as well as improve the health status and fitness of animals for a successful release back into the wild.

Circulation of Giardia duodenalis in domestic and wild animals from Amazon region: a Systematic Review

Giardia is an ubiquitous protozoa that infect a broad range of vertebrate hosts, including domestic and wild animals as well as humans. Giardia duodenalis is one of the most common parasite in humans and mammals worldwide. Human giardiasis is highly prevalent in the countries that make up from Amazon. The identification of genotypes in humans and animals improves the understanding of transmission routes and the control strategies. Thus, we carried out a systematic review on Giardia in animals from Amazon region/South American, following the PRISMA guidelines. Studies up to September, 2022 were searched for in public database. A total of seven out of 432 articles were selected: four, two and one from Brazil, Colombia and Peru, respectively. Based on these articles it is seen that the G. duodenalis cosmopolitan assemblages A and B prevail within domestic and wild animals in the Amazon. Moreover, a Giardia microscopic screening in aquatic animals from this biome showed its prevalence among aquatic mammals including the endangered species Trichechus inunguis (manatee). Therefore, a yet not accessed number of susceptible hosts, new G. duodenalis assemblages and species can be occurring in this huge hotspot of biodiversity that is Amazon region.

Infection rate and genetic diversity of Giardia duodenalis assemblage C in Iranian stray dogs, targeting the glutamate dehydrogenase gene

Background and Aim

Giardia duodenalis is one of the most common enteric protozoan parasites in vertebrates, such as humans, domestic and wild animals, causing giardiasis. To the best of our knowledge, little is known about the genetic diversity of G. duodenalis assemblages. This study aimed to identify genetic diversity of G. duodenalis assemblages in Iranian stray dogs.

Materials and Methods

A total of 450 fecal samples were collected from 2015 to 2016 from stray dogs of Northwest Iran. All specimens were observed microscopically following concentration and flotation techniques. Subsequently, DNA samples were extracted, amplified, and sequenced targeting the glutamate dehydrogenase gene.

Results

The overall prevalence of G. duodenalis in infected dogs was estimated at 1.6%, based on microscopic and molecular diagnoses. Sequencing and phylogenetic analyses indicated a high level of genetic diversity of assemblage C (haplotype diversity; 0.802).

Conclusion

The pairwise sequence distances between the identified isolates of assemblage C showed an intradiversity of 0.3%-1.3% and identity of 98.7%-100%. Current findings indicate that a significant genetic diversity of G. duodenalis assemblage C haplotypes is unequivocally circulates among stray dogs in Northwest Iran.

Parasite fauna of wild Antillean manatees (Trichechus manatus manatus) of the Andean Region, Colombia

BACKGROUND

Antillean manatees (Trichechus manatus manatus) are large herbivorous aquatic mammals living in limited areas of South, Central and North America. As with other aquatic mammals, Antillean manatees can be infected by a variety of protozoan and metazoan parasites, some of them with zoonotic potential, which affect not only their welfare but also population health status. Therefore, we conducted the first epidemiological survey in Colombian free-ranging Antillean manatees to estimate their actual gastrointestinal parasite status.

RESULTS

In total, 69 faecal samples were collected from free-ranging individual manatees during ecology field studies in the rivers Carare and San Juan and in two associated wetlands in the Andean region of Colombia. Parasite diversity encompassed six different endoparasite species. The highest prevalence was found for protozoan infections with Eimeria nodulosa (47.8%) and Eimeria manatus-like species (type A, B; 43.4%), followed by Entamoeba sp. (14.49%) and Giardia sp. (1.4%) infections. In addition, infections with the trematode Chiorchis fabaceus were detected at a high prevalence (33.3%). Molecular characterization of sirenian Eimeria species led to the distinction of three species, E. nodulosa and two E. manatus-like species (type A, B). Phylogenetic analyses indicated a host-specific adaptation of sirenian Eimeria species as previously reported for Eimeria species from other mammalian hosts.

CONCLUSIONS

This study provides the first record of Antillean manatee infection with Giardia and Entamoeba species in Colombia, representing two important anthropozoonotic parasite genera. This survey should serve as a baseline investigation for future monitoring on parasitic zoonoses in this mammal and encourage for investigations on their impact on both public health and wild manatee welfare.