Microscopic and molecular detection of Eimeria maxima and Eimeria praecox naturally infected in free-range village chickens of Myanmar

The global prevalence and associated risk factors of Eimeria infection in domestic chickens: A systematic review and meta-analysis

BACKGROUND

Eimeria is a protozoan parasite that affects poultry, particularly chickens, causing a disease known as coccidiosis. This disease imposes substantial significant economic challenges to the poultry sector.

OBJECTIVES

The current study aimed to estimate the global prevalence and associated risk factors of Eimeria in domestic chickens.

METHODS

Multiple databases (Scopus, PubMed, ProQuest, Web of Science and Google Scholar) were searched for articles published until June 2023. The pooled prevalence was estimated using a random-effects model with a 95% confidence interval. The statistical analysis was conducted using meta packages in R version (3.6.1).

RESULTS

In total, 41 articles fulfilled the eligibility criteria. The global pooled prevalence was 44.3% (36.9%-51.8%) with Eimeria tenella (38.7%, 30.1%-47.7%) as the most prevalent species. The highest pooled prevalence was related to the Western Pacific Region (80.5%, 72.6%-87.3%) and urban areas (44.4%, 36.5%-52.6%). Moreover, areas with humid subtropical climates represent the highest overall prevalence (75.8%, 46.6%-95.9%).

CONCLUSION

The necessity for robust and innovative strategies for preventing and managing this disease cannot be overstated. Addressing Eimeria impact is crucial not only for safeguarding poultry health but also for sustaining the economic viability of the poultry industry.

Prevalence of endoparasites by microscopic analysis in free-range chickens in a Brazilian semiarid region

The aim of this study was to evaluate the prevalence and diversity of endoparasitic fauna and the risk factors associated with parasite infections in free-range chickens in the state of Paraíba, northeastern Brazil. Ten municipalities were visited and, in each of them, ten farms, to collect animal feces and apply epidemiological questionnaires. Feces from 417 poultry were used to perform EPG (eggs per gram) and OoPG (oocysts per gram) tests. Prevalences of 40.52% (169/417) and 39.08% (163/417) were observed for nematodes and coccidia, respectively. In 17% (71/417), mixed infections by nematodes and coccidia were observed. Nematodes of Heterakoidea superfamily were present in 100% of the positive samples (169/169), followed by Trichuris spp. (57.3%; 97/169). All the protozoan oocysts observed belonged to the genus Eimeria (100%; 163/163). The variable of presence of drooping wings was considered to be a factor associated with infection by coccidia (odds ratio = 5.412; confidence interval: 1.179-24.848; p = 0.030). It was concluded that there is high prevalence of nematodes and coccidia in free-range chickens in the state of Paraíba, Brazil. Better sanitary management measures, with greater hygiene of facilities, together with chemical control of parasites, can improve productivity by reducing the rate of gastrointestinal parasites.

Morphological and molecular identification of trematode cercariae related with humans and animal health in freshwater snails from a lake and a dam in Myanmar

Freshwater snails play an essential role in the transmission of trematode parasitic flatworms that can infect wild and domestic animals, as well as humans. This study aimed to investigate the rate of cercarial infections in freshwater snails collected from two study areas, Inlay Lake and Yezin Dam, in Myanmar. A total of 4,740 snail samples were collected from Inlay Lake (n = 3,837) and Yezin Dam (n = 903), and infection rate by cercarial emergence was examined. Cercarial DNA samples were analysed by PCR. Based on morphological characteristics, eleven snail species and eight cercarial types were identified. Snails of Melanoides tuberculata in the family Thiaridae were found as the most abundant, followed by Indoplanorbis exustus of the family Planorbidae, in both study areas. The infection rate by cercarial emergence in snails in Inlay Lake and Yezin Dam was 5.8% (224/3,837) and 48.6% (439/903), respectively. Echinostome cercariae showed the highest infection rate in both study areas. Phylogenetic analysis of cercarial internal transcribed spacer 2 (ITS2) sequences revealed that at least seven cercaria types belonged to five digenean trematode families, two of which were zoonotic trematodes in the families of Opisthorchiidae/Heterophyidae and Schistosomatidae. Furthermore, cercarial 28S ribosomal RNA gene analysis showed that the furcocercous cercariae in Yezin Dam were identified as Schistosoma spindale, a causative agent of ruminant schistosomiasis. This is the first report on zoonotic trematode cercariae in snails in Myanmar. The findings indicate that various snail species act as intermediate host for trematode species that infect aquatic animals, mammals and humans in the country.