Prevalence and molecular characterization of Toxoplasma gondii in different types of poultry in Greece, associated risk factors and co-existence with Eimeria spp.

Abstract

Toxoplasma gondii is a protozoan parasite of public health importance, infecting all warm-blooded animals, including chickens. Undercooked chicken meat or relevant products such as sausages could lead to human infections. In free-range, organic and slow-growth farming systems where the susceptibility period for chickens is extended, more knowledge about potential risk factors is essential. This study is the first seroepidemiological survey in different regions and types of chicken farms in Greece, using a major tachyzoite surface antigen-based ELISA (TgSAG1), combined with magnetic-capture PCR (mc-PCR) and bioassay for the isolation of strains from the chickens’ tissues. Potential risk factors for T. gondii infection in these hosts were also investigated. Additionally, the co-existence of T. gondii and Eimeria spp. infections was assessed to elucidate epidemiological links between these two protozoan infections. Overall T. gondii seroprevalence was 9.5%. Of the backyard chickens sampled, 41.2% were seropositive and 70% of the organic and free-range layer farms had at least one T. gondii seropositive hen. No serologically positive broilers were found, although mc-PCR revealed a positive sample, highlighting the importance of accurate early-infection direct detection of T. gondii infections to ensure public health. T. gondii isolates obtained by mouse bioassay were genotyped. All belonged to type II (ToxoDB#3) as confirmed also by microsatellite typing. Production system, type of nutrition, and feeding system automation were identified as the most significant risk factors, while no association was found between the presence of cats and T. gondii seropositivity as calculated on both a farm level and per individual bird sampled.

Epidemiological investigation of coccidiosis and associated risk factors in broiler chickens immunized with live anticoccidial vaccines in China

“…This association was consistent with the finding identifying E. necatrix as a contributing factor to coccidiosis occurrence (8,35). This finding suggested that factors related to the host (e.g., underlying subclinical non-parasitic infections) and environmental factors (e.g., crowding, air quality, and stress) may negatively affect the health of vaccinated chickens, which increased the susceptibility of chickens to coccidiosis, similar to previous reports (21,29,36). Moreover, our study found that flocks infected with E. acervulina were also at a significantly higher risk of coccidiosis (OR = 1.59, 95% CI: 1.01-2.51; p < 0.05) when vaccinated with tetravalent vaccines.…”

“…The overall prevalence of coccidiosis in China is 86.12% (546 of 634 flocks). A comparably high prevalence has been reported in provinces in China such as Anhui (87.75%) ( 18 ), Hubei (97.79%), and Henan (96.70%) ( 16 ) and other countries including Greece (85.7%) ( 21 ), northeastern Algeria (99.5%) ( 22 ), Colombia (96.3%) ( 23 ), and Australia (98%) ( 24 ). Conversely, the prevalence was notably lower in Serbia, north India, Korean, northeastern Brazil, and southwestern Nigeria with rates of 59, 28.5, 75, 59, and 41.3% ( 25–29 ), respectively.…”

Toxoplasma gondii and Alternaria sp.: An Original Association in an Immunosuppressed Dog with Persistent Skin Lesions

“…Following an overnight digestion of 1/3rd of the punch biopsy with a trypsin medium, one part of the supernatant was used for DNA extraction and the other part was cell cultured on Human Foreskin Fibroblast (HFF) cell line, showing a rapid multiplication of protozoan tachyzoites. They both returned positive results when a T. gondii 529 bp RE-target real-time Polymerase Chain Reaction (PCR) [ 13 , 14 , 15 ] was performed. Punch biopsy DNA revealed a low Ct value of 16.3 in the T. gondii real-time PCR which is indicative of a high parasite DNA concentration and is in accordance with the histological observations ( Figure 2 D).…”

“…Genotyping by microsatellites and PCR-RFLP of the T. gondii tachyzoites issued from the HFF cell culture, and used a previously described method [ 13 ] based on 8 markers, which are distributed over eight chromosomes, and the apicoplast [ 18 ], namely nSAG2, SAG3, BTUB, GRA6, C22-8, C29-2, L358, PK1, Apico. Comparison with T. gondii reference strain DNAs of RH (Type I), Me49 (Type II) and NED (Type III) identified the present strain as Type II, Apico I, resembling ToxoDB#3.…”

Epidemiological risk factors and phylogenetic affinities of Sarcocystis infecting village chickens and pigs in Peninsular Malaysia

“…Permission for sample collection was given by the Research and Innovation Division, DVS as part of their ongoing annual disease surveillance program, and consent was obtained from randomly selected farms. The number of farms involved in this study was calculated under the supposition that Sarcocystis can be detected in at least 10% of the farms with a precision of 10% at a confidence level of 95% (Andreopoulou et al, 2023), given the uncertain prevalence of infections at farm level. Flocks containing >10 chickens per farm between the ages of 6-12 months and herds containing >25 pigs per farm that are older than 5 months were eligible for inclusion in this study.…”