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Background: Coccidiosis is one of the most frequently reported diseases in chickens, causing a significant economic impact on the poultry industry. However, there have been no previous studies evaluating the prevalence of this disease in broiler farms in Guangdong province. Therefore, this study aims to conduct an epidemiological investigation into the occurrence of Eimeria species and associated risk factors in intensive management conditions across four regions in Guangdong province, China. A total of 394 fecal samples were collected from 89 broiler farms in Guangdong province. The prevalence of Eimeria species infection was determined using PCR, and the occurrence of Clostridium perfringens type A was assessed using quantitative real-time PCR. Results: The results showed an overall prevalence of 98.88% (88/89) at the farm level and 87.06% (343/394) at the flock level. All seven Eimeria species were identified, with E. acervulina (72.53%; 64/89), E. tenella (68.54%; 61/89), and E. mitis (66.29%; 59/89) at the farm level, and E. acervulina (36.55%; 144/394), E. mitis (35.28%; 139/394), and E. tenella (34.01%; 134/394) at the flock level. The predominant species combination observed was a co-infection of all seven Eimeria species (6.74%; 6/89), followed by a combination of E. acervulina, E. tenella, E. mitis, E. necatrix, E. brunetti, and E. maxima (5.62%, 5/89). A combination of E. acervulina, E. tenella, E. mitis, E. necatrix, E. brunetti, and E. praecox (4.49%; 4/89) was also observed at the farm level. Furthermore, the study identified several potential risk factors associated with the prevalence of Eimeria species, including farm location, chicken age, drinking water source, control strategy, and the presence of C. perfringens type A were identified as potential risk factors associated with prevalence of Eimeria species. Univariate and multivariate analyses revealed a significant association between E. necatrix infection and both grower chickens (OR = 10.86; 95% CI: 1.92–61.36; p < 0.05) and adult chickens (OR = 24.97; 95% CI: 4.29–145.15; p < 0.001) compared to starter chickens at the farm level. Additionally, farms that used groundwater (OR = 0.27; 95% CI: 0.08–0.94; p < 0.05) were less likely to have E. maxima compared to those that used running water. At the flock level, the prevalence of E. tenella was significantly higher in the Pearl River Delta (OR = 2.48; 95% CI: 1.0–6.15; p = 0.05) compared to eastern Guangdong. Interestingly, flocks with indigenous birds were less likely to have E. brunetti (OR = 0.48; 95% CI: 0.26–0.89; p < 0.05) compared to flocks with indigenous crossbred birds. Furthermore, flocks that used anticoccidial drugs (OR = 0.09; 95% CI: 0.03–0.31; p < 0.001) or a combination of vaccines and anticoccidial drugs (OR = 0.06; 95% CI: 0.01–0.25; p < 0.001) were less likely to be positive for E. tenella compared to flocks that only used vaccines. Finally, flocks with C. perfringens type A infection were significantly more likely to have E. necatrix (OR = 3.26; 95% CI: 1.96–5.43; p < 0.001), E. tenella (OR = 2.14; 95% CI: 1.36–3.36; p < 0.001), E. brunetti (OR = 2.48; 95% CI: 1.45–4.23; p < 0.001), and E. acervulina (OR = 2.62; 95% CI: 1.69–4.06; p < 0.001) compared to flocks without C. perfringens type A. Conclusions: This study conducted an investigation on the prevalence, distribution, and risk factors associated with Eimeria species infection in broiler chickens in Guangdong. The farm-level prevalence of Eimeria species was higher than the previous prevalence figures for other areas and countries. E. brunetti was identified at higher prevalence in Guangdong than previously survived prevalence in different regions in China. Farm location, chicken age, drinking water source, control strategy, and the presence of C. perfringens type A were considered as potential risk factors associated with prevalence of Eimeria species. It is imperative to underscore the necessity for further surveys to delve deeper into the occurrence of Eimeria species under intensive management conditions for different flock purposes. [ABSTRACT FROM AUTHOR]

Pigeon farming for meat has developed into an important economic industry in most countries, especially in China. Trichomoniasis, caused by the protozoan parasite Trichomonas gallinae, is a worldwide disease in pigeons. However, studies of the prevalence and distribution of T. gallinae lineages in domestic pigeons in southern China are limited. In this study, a total of 636 pigeon throat swabs samples from four regions in Guangdong Province were screened for T. gallinae by in vitro culture assays and microscopy. The results revealed an overall prevalence of T. gallinae infection in southern China of 26.6% (169/636). There were significant differences in the infection rate of T. gallinae between the four regions (χ2 = 117.948, df = 4, P = 0.000), with up to 44.6% in the Pearl River Delta region. The infection rate of young pigeons was as high as 70.8%. The rDNA sequences (18S rRNA/ITS1-5.8S rRNA-ITS2) of 153 positive samples were amplified and sequenced. Results identified 58.2% (89/153) overall as ITS-A (18S-VI) (also known as ITS-OBT-Tg-1) and 41.8% (64/153) as ITS-B (18S-IV) (also known as ITS-OBT-Tg-2). Thus, ITS-A (18S-VI) was the dominant T. gallinae genotype in southern China, especially in young pigeon (97.0%, 32/33). In conclusion, a high prevalence of T. gallinae infection in domestic pigeons was identified in southern China, particularly in the Pearl River Delta region. The ITS-A (18S-VI) was the dominant genotype highly pathogenic, which may weaken the immune system of pigeons, and cause a negative impact on the development of the pigeon industry in China. [ABSTRACT FROM AUTHOR]

Background: Cryptosporidium is one of the most prevalent parasites infecting both birds and mammals. To examine the prevalence of Cryptosporidium species and evaluate the public health significance of domestic chickens in Guangdong Province, southern China, we analyzed 1001 fecal samples from 43 intensive broiler chicken farms across six distinct geographical regions. Methods: Individual DNA samples were subjected to nested PCR-based amplification and sequencing of the small subunit of the nuclear ribosomal RNA gene (SSU rRNA). Analysis of the 60 kDa glycoprotein gene (gp60) was performed to characterize the subtypes of C. meleagridis. Results: The overall prevalence of Cryptosporidium was 13.2% (95% CI 11.1–15.3) (24 of 43 farms), with C. meleagridis (7.8%), C. baileyi (4.8%) and mixed infections (0.6%). Using the gp60 gene, three subtype families, IIIb, IIIe and IIIg, were identified, including six subtypes: one novel (IIIgA25G3R1a) and five previously reported (IIIbA23G1R1c, IIIbA24G1R1, IIIbA21G1R1a, IIIeA17G2R1 and IIIeA26G2R1). Within these subtypes, five known subtypes were genetically identical to those identified in humans. Conclusions: This is the first report of C. meleagridis in chickens from Guangdong. The frequent occurrence of C. meleagridis in domestic chickens and the common C. meleagridis subtypes identified in both humans and chickens is of public health significance. Our study indicates that broiler chickens represent a potential zoonotic risk for the transmission of Cryptosporidium in this region. [ABSTRACT FROM AUTHOR]

Coronavirus infections cause diseases that range from mild to severe in mammals and birds. In this study, we detected coronavirus infections in 748 farmed wild animals of 23 species in Guangdong, southern China, by RT-PCR and metagenomic analysis. We identified four coronaviruses in these wild animals and analysed their evolutionary origins. Coronaviruses detected in Rhizomys sinensis were genetically grouped into canine and rodent coronaviruses, which were likely recombinants of canine and rodent coronaviruses. The coronavirus found in Phasianus colchicus was a recombinant pheasant coronavirus of turkey coronavirus and infectious bronchitis virus. The coronavirus in Paguma larvata had a high nucleotide identity (94.6–98.5 per cent) with a coronavirus of bottlenose dolphin (Tursiops truncates). These findings suggested that the wildlife coronaviruses may have experienced homologous recombination and/or crossed the species barrier, likely resulting in the emergence of new coronaviruses. It is necessary to reduce human–animal interactions by prohibiting the eating and raising of wild animals, which may contribute to preventing the emergence of the next coronavirus pandemic. [ABSTRACT FROM AUTHOR]

Background: Enterocytozoon bieneusi, a common opportunistic fungal pathogen, has a wide range of hosts. Limited epidemiological data on E. bieneusi intestinal infections in companion animals (dogs and cats) in China exists. In this study, fecal samples (651 from dogs and 389 from cats) in Guangzhou city, Guangdong Province, China, were collected, and the ribosomal internal transcribed (ITS) spacer region from the DNA extracted from them was Polymerase Chain Reaction (PCR)-amplified and sequenced. Results: Based on the sequencing data, E. bieneusi was identified in the fecal samples collected from 149 (22.9%) and 79 (20.3%) dogs and cats. Of the factors investigated, poor living conditions appeared to be the major risk factor for contracting the pathogen. Eleven E. bieneusi genotypes, six known (PtEb IX, GD1, D, CD9, EbpC, I) and five novel (designated here as GD2– GD6), were found in dogs. Eight genotypes, six known (PtEb IX, GD1, D, CD9, EbpC, Type IV) and two novel (GD2 and GC1), were identified in cats. Genotype PtEb IX was most common in both dogs and cats, followed by genotype GD1. Conclusions: Although PtEb IX was the most common E. bieneusi genotype in dogs, this is the first report of this genotype dominating in cats. The same genotype distribution of the pathogen between the two different companion animals species in the same geographic area indicates that inter-species transmission is probable. The widespread existence of zoonotic E. bieneusi genotypes (D, EbpC, Type IV) in companion animals indicates that they are potential sources of environmental contamination and infections in humans. [ABSTRACT FROM AUTHOR]

To investigate the prevalence and assess the zoonotic transmission burden of Cryptosporidium species in domestic pigeons in Guangdong Province, Southern China, 244 fecal samples were collected from four pigeon breeding farms between June 2012 and March 2013. Cryptosporidium oocysts were purified by Sheather's sugar flotation technique and characterized by DNA sequencing of small subunit ribosomal RNA (SSU rRNA) gene. Cryptosporidium species were determined by comparison of sequences with corresponding Cryptosporidium sequences in GenBank and phylogenetic analysis using neighbor-joining (NJ) in MEGA5.2. The overall prevalence of Cryptosporidium infection in domestic pigeons in Guangdong Province was 0.82 % (2/244). Two Cryptosporidium species, namely Cryptosporidium baileyi and Cryptosporidium meleagridis, were identified in Huizhou and Chaozhou farm, respectively. These findings confirmed the existence of C. meleagridis infection in domestic pigeons in China for the first time and provided base-line information for further studies to evaluate the public health risk from pigeon to human. [ABSTRACT FROM AUTHOR]

Abstract Giardia duodenalis is a gastrointestinal parasitic protozoan with important veterinary and public health implications worldwide. In this study, a total of 1440 fecal specimens were collected from dairy calves in Guangdong Province, China. The overall prevalence of G. duodenalis was 2.2% (31/1440) by polymerase chain reaction (PCR). The prevalence was 8.4% and 1.1% in pre- and post-weaned calves, respectively. Both assemblages A (6.5%, 2/31) and E (93.5%, 29/31) were found based on sequence analysis of the SSU rRNA gene. All G. duodenalis -positive samples were assayed with PCR followed by sequencing the beta giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) genes, and 20, 23, and 18 sequences were obtained, respectively. Multilocus genotyping yielded 10 assemblage E multilocus genotypes (MLGs). All assemblage E MLGs were genetically distinct from those obtained in cattle from Henan, Xinjiang, Shanghai, and Shaanxi in China. This finding was also supported by F ST , N m , and median-joining network analysis. Results of this study indicated that G. duodenalis was found in low prevalence in dairy calves in Guangdong Province, southern China; nevertheless, the infected calves might represent a public health risk in this region. Additionally, the differences in assemblage E MLGs from the five analyzed regions revealed significant geographic segregation of G. duodenalis in China. Graphical abstract Unlabelled Image Highlights • Both assemblages A and E of Giardia duodenalis were found in dairy calves. • The infected calves might represent a public health risk in this region. • Geographic segregation has shown in assemblage E of G. duodenalis in China. [ABSTRACT FROM AUTHOR]