Blastocystis spp., Enterocytozoon bieneusi, and Giardia duodenalis are three common zoonotic intestinal parasites that cause severe diarrhea and enteric diseases. Leizhou black goats are characterized by a high reproductive rate, fast growth, and good meat quality, making them one of the pre-eminent goat breeds in China. Goats are reportedly common reservoirs of these three intestinal pathogens, but no information on their prevalence or genotypic distributions in black goats in Guangdong Province, China, is available. A total of 226 fecal samples were collected from goats in Zhanjiang city and genomic DNA was extracted from them. The presence of the three pathogens was detected using nested PCR targeting the sequences encoding SSU rRNA (Blastocystis spp.), the internal transcribed spacer of rRNA (ITS; E. bieneusi), as well as beta-giardin, glutamate dehydrogenase, and triosephosphate isomerase (G. duodenalis). All PCR products were sequenced to determine the species and genotypes of the organisms. The total prevalence rates of Blastocystis spp., E. bieneusi, and G. duodenalis were 33.63% (76/226), 17.70% (40/226), and 24.78% (56/226), respectively. Four subtypes of Blastocystis spp. were detected: ST5 (n = 6), ST10 (n = 50), ST14 (n = 14), and ST21 (n = 6). Among them, ST10 was the dominant genotype, accounting for 65.79% of strains, followed by the genotypes ST14 (18.42%), zoonotic ST5 (7.89%), and ST21 (7.89%). Four genotypes of E. bieneusi were detected: CHG3 (n = 32), CM21 (n = 4), CHG1 (n = 2), and ET-L2 (n = 2). Among these, CHG3 was the dominant genotype. Assemblage E (n = 54) and concurrent assemblages A and E (n = 2) were identified in the G. duodenalis-positive goats using multilocus genotyping. Blastocystis spp., E. bieneusi, and G. duodenalis infections were common in Leizhou black goats, all of which have zoonotic genotypes, indicating the potential risk of zoonotic transmission. Our results provide basic data for the prevention and control of these three intestinal pathogens. Further studies are required to better understand their genetic characteristics and zoonotic potential in Guangdong Province.

Blastocystis spp. and Enterocytozoon bieneusi are common intestinal pathogens capable of infecting both humans and animals, which lead to severe diarrhea and other intestinal diseases, posing a threat to public health. The Bamaxiang pig, a specialty of Bama Yao Autonomous County in Guangxi Province, China, is an important local breed in the regional pork market and an excellent model animal for biomedical research. Currently, no data is available on the prevalence or genotype distribution of these pathogens in Bamaxiang pigs. This study aimed to determine the prevalence and genetic characteristics of Blastocystis spp. and E. bieneusi in three Bamaxiang pig farms located in Bama Yao Autonomous County, using molecular techniques based on the small subunit ribosomal RNA (SSU rRNA) gene fragment of Blastocystis spp. and the internal transcribed spacer (ITS) region of E. bieneusi. All positive PCR products from the 311 fecal samples were sequenced to identify the species and genotypes of these organisms. The overall infection rates of Blastocystis spp. and E. bieneusi were 34.08% (106/311) and 18.32% (57/311), respectively. Three subtypes of Blastocystis spp. were detected: ST1 (n = 8), ST3 (n = 3), and ST5 (n = 95). Among them, zoonotic ST5 was the dominant genotype, accounting for 89.62% (95/106) of strains, followed by the genotypes ST1 (7.54%, 8/106) and ST3 (2.83%, 3/106). Two genotypes of E. bieneusi were detected: EbpC (n = 52) and CHG23 (n = 5), with EbpC being the dominant genotype. The human-pathogenic subtypes (ST1, ST3, and ST5) and genotypes (EbpC, CHG23) that were observed in this study indicate a potential threat to public health. Our findings offer basic information for preventing and controlling these zoonotic pathogens in the study area. Additional investigations are necessary to better understand their genetic characteristics and zoonotic potential within Guangxi Province.

To address diagnostic challenges associated with caprine schistosomiasis under persistent transmission risks, this study evaluated the diagnostic performance of four recombinant antigens (rSjSAP4, rSj32, rSjCB1, and rSj23), with soluble egg antigen (SEA) serving as the reference comparator. An optimized indirect enzyme-linked immunosorbent assay (ELISA) was used to test serum samples from well-characterized goat panels, comprising 94 positive samples from goats experimentally infected with Schistosoma japonicum and 100 negative samples. Of the four recombinant antigens evaluated, rSjCB1 demonstrated the highest sensitivity (97.87%), whereas rSjSAP4 exhibited the highest specificity (98.00%). Receiver operating characteristic (ROC) curve analysis yielded Area Under the Curve (AUC) values of 0.8497, 0.9895, 0.8928, and 0.8050 for rSjSAP4, rSjCB1, rSj32, and rSj23, respectively. A mixture containing equal concentrations of rSjCB1 and rSjSAP4 achieved balanced performance (sensitivity: 93.62%, specificity: 92.00%; AUC = 0.9472) and excellent agreement with the reference standard (κ = 0.86). In conclusion, rSjCB1 appears to be the most promising single diagnostic antigen, and an equal-concentration mixture of rSjCB1 and rSjSAP4 represents a practical diagnostic alternative to SEA for the development of rapid and accurate immunoassays for caprine schistosomiasis.

Background: Giardia duodenalis is one of the most prevalent protozoan pathogens, commonly infecting a wide range of hosts including humans, livestock, companion animals, and wildlife globally. The Bamaxiang pig (Sus scrofa domesticus), a native livestock variety from China’s Guangxi region, holds significant importance in Bama Yao Autonomous County. This breed not only supports regional meat production systems but also fulfills dual roles as human companions and valuable subjects for biomedical investigations. The aim of present study was to investigate the prevalence of G. duodenalis and assess its genetic characteristics. A total of 311 fresh fecal samples were collected from three farms in Bama Yao Autonomous County. The presence and genetic diversity of G. duodenalis were determined by nested PCR and sequence analysis of the glutamate dehydrogenase (gdh), β-giardin (bg) and triose phosphate isomerase (tpi) genes. Results: The total occurrence rate of G. duodenalis in Bamaxiang Pigs was 17.36% (54/311). Among different age groups, suckling piglets exhibited the highest infection rate at 24.29% (17/70). The infection rates in the sows, fattening pigs, and weaned piglets were 20.88% (19/91), 14.10% (11/78), and 9.72% (7/72), respectively (p < 0.05). Phylogenetic analysis of sequences from three genetic loci identified two G.duodenalis genetic assemblages, namely assemblages A and E. Among them, assemblage A (n = 31) was the predominant genotype across the three farms, followed by the assemblage E (n = 21) and mixed assemblage A/E (n = 2) infections. Conclusions: This study represents the first report demonstrating that G. duodenalis infection is prevalent in Bamaxiang pigs, with variable positivity rates across different growth stages. The zoonotic assemblage A was the predominant assemblage, suggesting a potential risk of transmission to humans through close contact with this specific pig breed. The results provide basic data for controlling infections in Bamaxiang pigs.