Prevalence of coccidia in domestic pigs in China between 1980 and 2019: a systematic review and meta-analysis

Global prevalence of lagomorpha coccidiosis from 1951 to 2024: A systematic review and meta-analysis

The global prevalence of coccidia infection in lagomorphs and potential risk factors were investigated through a meta-analysis of 149 studies published between 1951 and 2024. The pooled prevalence of Eimeriidae, Sarcocystidae and Cryptosporidiidae was found to be 66.0 %, 8.0 % and 6.1 %, respectively. Rabbits and hares exhibited the highest prevalence of Eimeriidae at 63.1 % and 71.8 %, while pikas had the highest prevalence of Cryptosporidiidae at 17.1 %. Countries located in the southern hemisphere exhibited the highest prevalence of Cryptosporidiidae (11.4 %). The African Region had the highest prevalence of Eimeriidae (73.3 %) and Sarcocystidae(14.6 %), while the Eastern Mediterranean Region had the highest prevalence of Cryptosporidiidae(13.6 %). Juvenile rabbits exhibited the highest prevalence of Eimeriidae (67.4 %), while senior Rabbit exhibited the highest prevalence of Sarcocystidae(17.1 %) and Cryptosporidiidae(13.1 %). The prevalence of coccidia in intensively farmed lagomorphs showed a slight upward trend over time, nearly reaching statistical significance (R2 = 7.88 %, coefficient = 0.019, P = 0.127). This suggests that the current intensive farming practices may be losing effectiveness in controlling coccidia infections, which is concerning. Among Eimeriidae in lagomorphs, Eimeria coquelinae showed the highest prevalence (68.4 %), while E. magna was most frequently reported. For Sarcocystidae, Besnoitia spp. had the highest prevalence (31.3 %), with Toxoplasma gondii being most frequently reported. Cryptosporidium cuniculus was both the most prevalent and frequently reported Cryptosporidiidae species (6.9 %), suggesting it may be a major Cryptosporidiidae pathogen in lagomorphs. These findings highlight the differences in prevalence of various Eimeriida species among different lagomorpha genera. This diversity underscores the complex relationships between specific parasites and their host species, contributing to a more nuanced understanding of coccidiosis epidemiology in lagomorphs worldwide.

Development of deep learning-based mobile application for the identification of Coccidia species in pigs using microscopic images

Coccidiosis is a gastrointestinal parasitic disease caused by different species of Eimeria and Isospora, poses a significant threat to pig farming, leading to substantial economic losses attributed to reduced growth rates, poor feed conversion, increased mortality rates, and the expense of treatment. Traditional methods for identifying Coccidia species in pigs rely on fecal examination and microscopic analysis, necessitating expert personnel for accurate species identification. To address this need, a deep learning-based mobile application capable of automatically identifying different species of Eimeria and Isospora was developed. The present study focused on six species, namely, E. debliecki, E. perminuta, E. porci, E. spinosa, E. suis, and Isospora suis, commonly found in pigs of the North Eastern Hill (NEH) region of India. Utilizing a two-stage approach, segmentation of coccidia oocysts in microscopic images using convolutional neural networks (CNNs), followed by species identification by same network was carried out in this work. Resource-efficient models, including EfficientNetB0, EfficientNetB1, MobileNet, and MobileNetV2, within an encoder-decoder architecture were utilized to extract features. Transfer learning was applied to enhance model accuracy during training. Additionally, a marker-controlled watershed algorithm was implemented to separate touching cells, thus reducing misclassification. The results demonstrate that all the developed models effectively segmented/classified Coccidia species, achieving mean Intersection-over-Union (m-IoU) values exceeding 0.92, with individual class IoU scores above 0.90. MobileNetV2 exhibited the highest m-IoU of 0.95, followed by EfficientNetB1 with an m-IoU of 0.94. For classification, MobileNetV2 demonstrated the highest performance, with accuracy, precision, and recall values of 0.93, 0.96, and 0.96, respectively. EfficientNetB1 yielded an accuracy of 0.91. The developed mobile application, tested on new data, achieved an identification accuracy of 91.0 %. These findings highlight the potential of deep learning-based mobile applications in effectively identifying Coccidia species in pigs, thus, providing a promising solution to mitigate reliance on expert personnel and laborious time-consuming experiments in this domain.

Global prevalence of Eimeria species in goats: a systematic review and meta-analysis

Background

Coccidiosis is a protozoal disease caused by Eimeria species, the main symptom of which is diarrhea. Eimeria spp. infection can cause weight loss and ill-thrift in goats, and in severe cases, it can lead to mortality in kids, resulting in economic losses for the goat industry. This study aimed to determine the global prevalence of Eimeria spp. in goats and to identify the possible predictors of heterogeneity among selected studies.

Methods

Data were retrieved from five databases of major global importance (PubMed, Web of Science, CAB Direct, Scopus, and Google Scholar), with 255 studies published between 1963 and 2022 being included. A random-effects model was used to calculate pooled prevalence estimates with 95% confidence intervals (CI), followed by subgroup meta-analysis and meta-regression analysis to identify factors contributing to high prevalence and explore sources of heterogeneity among studies.

Results

The estimated global prevalence of Eimeria spp. in goats was 62.9% (95% CI: 58.6-67.2). Our results indicated high inter-study variability (inconsistency index (I2) = 99.7%, p < 0.01). Among the variables analyzed, regions and quality of studies were the most significant predictors of heterogeneity. According to the region-based subgroup meta-analysis, North America had the highest estimated prevalence of Eimeria spp. (92.2, 95% CI: 82.7-98.2), followed by Europe (86.6, 95% CI: 79.8-92.3), while Asia had the lowest prevalence (52.0, 95% CI: 45.9-58.1). Most countries (n = 42/56) had an estimated prevalence above the overall pooled estimate (>62.9%). The subgroup of studies conducted in 2000 or later presented a lower prevalence of 59.6% (95% CI: 54.7-64.3). Studies with a score of 5-7 had a significantly higher prevalence (72.4, 95% CI: 66.2-78.2) than studies with low or medium scores (p < 0.01). The prevalence of Eimeria spp. in goats detected with conventional and molecular methods was 67.3% (95% CI: 47.0-84.7). Only 47% (119/255) of the studies provided details on identifying Eimeria at the species level. Overall, more than 26 Eimeria spp. have been identified in goats globally. Among these, the most frequently reported and pathogenic species were E. arloingi (115/119), E. ninakohlyakimovae (108/119), E. christenseni (94/119), and E. caprina (71/119). Other valid species that were reported less frequently include E. alijevi, E. hirci, E. caprovina, E. aspheronica and E. jolchijevi.

Conclusion

These findings suggest that the pathogenic Eimeria spp. are widespread in goats globally. Given the high prevalence and the extensive distribution of pathogenic Eimeria spp. in goats, it is recommended that integrated parasite management approaches be implemented for the effective control of coccidiosis in goats.

Morphological and molecular characteristics of swine coccidia based on single oocyst isolation

Swine coccidiosis is a host-specific protozoan disease caused by Cystoisospora suis and various Eimeria species, leading to diarrhea or subclinical signs in pigs. In this study, 3296 fecal samples from 55 farms across six provinces in China were collected and examined to determine the prevalence and molecular characteristics of swine coccidia. The single oocyst isolation technique (SOIT) and molecular characterization identified nine coccidian species, with an overall infection prevalence of 13.83%. Infection rates varied by locations, host age groups, and sampling seasons. Among the positive swine coccidia samples, Cystoisospora suis showed the highest prevalence at 58.77%, followed by eight Eimeria spp. species. SOIT along with molecular characterization of C. suis at the SSU rRNA and ITS rRNA gene loci revealed the sequence homology from 99.8 to 100.0%. Additionally, the eight species of Eimeria. exhibited a high degree of sequence homology at the SSU rRNA and COX I gene loci. Due to the limitation of single molecular marker genes, this study introduced SOIT for DNA extraction, followed by nested PCR amplification of the SSU rRNA, ITS rRNA, and COX I gene loci to identify swine coccidia. This study is the first to systematically evaluate the prevalence and genetic diversity of coccidia in Chinese pig farms by SOIT, offering a method for accurately identifying swine coccidiosis and a scientific foundation for its effective prevention and control.

Coccidia Species and Geographical Distribution in Genus Sus: A Scoping Review

Swine coccidiosis is a widespread disease caused by species of the apicomplexan parasites Eimeria and Cystoisospora. Coccidiosis is a common cause of diarrhea in suckling piglets worldwide that directly reduces piglets' immunity and increases the risk of infection with other enteropathogens, leading to increased clinical infection and mortality and consequent economic losses in the global pig industry. We searched the available literature to date, including English and Chinese articles, using six electronic bibliographic databases, including PubMed, ScienceDirect, Web of Science, CNKI, VIP Chinese Journal Database, and Wanfang Data. A standard approach for conducting scoping reviews was used to identify studies on the species and distribution of genus Sus coccidia worldwide. A quality assessment was done for each study reviewed and relevant information reported in the identified studies was collated, categorized, and summarized. A total of 149 publications and references were eligible for the final review. The distribution of 18 species of genus Sus coccidia recorded in 63 countries was collated. These included 15 Eimeria and 3 Cystoisospora species. C. suis was found in 48 countries, E. debliecki in 45 countries, E. scabra in 33 countries, E. polita in 31 countries, E. suis in 28 countries, E. perminuta in 26 countries, E. porci in 24 countries, E. neodebliecki and E.spinosa in 21 countries each, E.guevarai in 5 countries, C. almataensis in 4 countries, E. betica in 2 countries, and E. almataensis, E. ibrahimovae, E. residualis, E. szechuanensis, E. yanglingensis, and C. sundarbanensis were each found in only 1 country. Each species was listed according to its scientific name, host name, finding location, and geographical distribution. This review reflects the distribution and infection of genus Sus coccidia worldwide and provides more complete basic information to aid our understanding of the species and geographical distribution of coccidia in the genus Sus.

Prevalence of coccidia in lagomorphs in China between 1981 and 2023: A systematic review and meta-analysis

Lagomorpha coccidiosis, caused by coccidia, is a prevalent disease affecting rabbits, hares and pikas. This meta-analysis aimed to estimate the pooled prevalence of coccidia infection in lagomorphs and identify potential risk factors. A systematic search of six databases yielded 102 studies published between 1981 and 2023. The pooled prevalence of Eimeriidae, Sarcocystidae and Cryptosporidiidae in lagomorphs was 76.4%, 6.2% and 3.9%, respectively. Rabbits had the highest prevalence of Eimeriidae (76.8%) and Sarcocystidae (7.4%), while pikas had the highest prevalence of Cryptosporidiidae (6.2%). Juvenile rabbits exhibited the highest prevalence of Eimeriidae (84.6%) and Cryptosporidiidae (9.9%). Northwest China had the highest prevalence of Eimeriidae (87.8%). Over time, the prevalence of Eimeriidae declined (Coefficient: -0.0062; P<0.05), but remained high (65.0%) in the past five years. Our findings highlight the prevalence of Eimeriidae infection in lagomorphs and the need for further research on Sarcocystidae and Cryptosporidiidae infections. We emphasize the importance of developing lagomorpha coccidia vaccines and implementing vaccination schedules for juvenile rabbits to mitigate coccidia infections.

Parasites burden in peri-urban free-roaming pigs in Gert Sibande District Municipality, Mpumalanga Province, South Africa

BACKGROUND

Parasite infections, unlike regulated animal diseases, do not often receive attention. In fact, parasites are major sources of financial losses in pig enterprises, particularly in subsistence and small-scale pig production systems.

OBJECTIVE

To identify and quantify the prevalence of ecto- and endo-parasites among peri-urban free-roaming pigs (FRP) in Gert Sibande District Municipality (GSDM), Mpumalanga.

METHODS

Pig owners were identified using the snowball sampling method since no sampling frame for FRP farmers exists. Stratified sampling was used to select pigs for sampling for ecto- and endo-parasites. A form was used to record the observations. Pairwise correlation analysis was performed using Stata 15.0. The SPSS V28.0 statistical package was used to perform the chi-square test (X2) to assess the distribution of parasites in different age groups. The prevalence of parasites was assessed in different age groups of pigs using multi-response crosstabs. Multivariate analysis of variance (MANOVA) was used to estimate the marginal mean of parasites according to municipality. Statistical significance was assessed at α ≤ 0.05.

RESULTS

Over 90% (91.2%) of the pigs examined were infested with at least one parasite, including Haematopinus suis, Sarcoptes scabiei, Ascaris suum, Fasciola hepatica, Trichuris suis, Strongylids, Coccidia spp, Moniezia expansa, and Siphonaptera spp. The correlation between Ascaris suum and body condition was weak but statistically significant (r = 0.24; p < 0.05).

CONCLUSION

Policy makers, animal researchers and veterinary services must focus on developing policies, risk communication and community engagement materials, which target pig farmers in peri-urban areas such as Gert Sibande District Municipality, Mpumalanga Province.

On the efficacy of preventive toltrazuril treatments and the diagnosis of Cystoisospora suis infections in intensively raised piglets in farms from southeast Spain

This study investigated the presence and abundance of Cystoisospora suis oocysts in faecal samples from 131 one- to three-week-old pig litters belonging to eight intensively raised, indoor herds in Spain. Seven herds used preventive anticoccidial toltrazuril treatments administered orally or by intramuscular injection, and one did not use preventive anticoccidial treatments. The diagnosis was performed using two oocyst flotation-concentration methods, Bailenger's method in every herd and the more recent Joachim's method in four herds. Oocysts were detected in every farm, the proportion of oocyst-positive samples was higher with Bailenger's technique, and the estimated overall prevalence (95% confidence interval) was 40 (32-49)%, including 47 (29-65)% in non-medicated litters, 52 (38-67)% in orally medicated litters and 28 (16-40)% in intramuscularly medicated litters (p < 0.05). However, mixed logistic regression models indicated that the risk of infection was not significantly associated with preventive anticoccidial treatments (p > 0.05), and increased with age, was higher in herds with partially compared to fully slatted dung floors in farrowing pens and in litters with pigs with diarrhoea (p < 0.05). The median (range) oocysts per gram of faeces (OpG) in infected litters by Bailenger's method was 623 (35-49048) and mixed negative binomial models revealed no significant association between infection intensity in positive litters and pen's floor type and piglets age, faecal consistency and treatment status (p > 0.05). The apparent low efficacy of Toltrazuril suggests treatment administration failures, reduced residual efficacy or low susceptibility of C. suis strains in study farms and needs further investigation.

The prevailing infection of Schistosoma japonicum and other zoonotic parasites in bubaline reservoir hosts in the ricefield of lake ecosystem: the case of Lake Mainit, Philippines

Bovines are important reservoir hosts of schistosomiasis, placing humans and animals in rice fields areas at risk of infection. This study reported the prevailing infection of zoonotic parasites from bovine feces in the rice fields adjacent to Lake Mainit, Philippines. Formalin Ethyl Acetate Sedimentation was performed on 124 bovine fecal samples from rice fields and documented eggs and cysts from seven parasites: Schistosoma japonicum, Fasciola gigantica, Ascaris sp., Strongyloides sp., Balantidium coli, coccidian oocyst and a hookworm species. Among these parasites, F. gigantica harboured the highest infection with a 100% prevalence rate, followed by hookworms (51.61%), B. coli (30.64%) and S. japonicum (12.09%), respectively. The intensity of infection of S. japonicum eggs per gram (MPEG = 4.19) among bovines is categorized as ‘light.’ Bovine contamination index (BCI) calculations revealed that, on average, infected bovines in rice fields excrete 104 750 S. japonicum eggs daily. However, across all ricefield stations, bovines were heavily infected with fascioliasis with BCI at 162 700 F. gigantica eggs per day. The study reports that apart from the persistent cases of schistosomiasis in the area, bovines in these rice fields are also heavily infected with fascioliasis. The study confirms the critical role of bovines as a reservoir host for continued infection of schistosomiasis, fascioliasis and other diseases in the rice fields of Lake Mainit. Immediate intervention to manage the spread of these diseases in bovines is recommended.

Prevalence and potential risk factors of PDCoV in pigs based on publications during 2015-2021 in China: Comprehensive literature review and meta-analysis

Porcine deltacoronavirus (PDCoV), a novel coronavirus which infects pigs, spreading around the world and causing huge economic losses. In recent years, there have also been human cases of PDCoV infection, which poses a potential threat to public health. Therefore, we conducted a systematic review and meta-analysis to assess the prevalence of PDCoV in pigs in China between 2015 and 2021. The prevalence of PDCoV in China was searched from five databases (CNKI, VIP, WanFang, PubMed and ScienceDirect) and 65 articles met the inclusion criteria, with a total of 25,977 samples, including 3828 positive cases. The overall prevalence of PDCoV was 13.61% (3828/25,977), with the highest prevalence in northern China (19.18%) and the lowest prevalence in southwest China (7.19%). We also analyzed other subgroup information, such as sampling years, test methods, age and geographic factors. The results show that PDCoV is endemic in China and climate may be a potential risk factor for PDCoV infection. It is suggested that appropriate measures should be taken in different climatic areas to reduce local PDCoV infection.

Diagnostic Approach to Enteric Disorders in Pigs

The diagnosis of enteric disorders in pigs is extremely challenging, at any age. Outbreaks of enteric disease in pigs are frequently multifactorial and multiple microorganisms can co-exist and interact. Furthermore, several pathogens, such as Clostridium perfrigens type A, Rotavirus and Lawsonia intracellularis, may be present in the gut in the absence of clinical signs. Thus, diagnosis must be based on a differential approach in order to develop a tailored control strategy, considering that treatment and control programs for enteric diseases are pathogen-specific. Correct sampling for laboratory analyses is fundamental for the diagnostic work-up of enteric disease in pigs. For example, histology is the diagnostic gold standard for several enteric disorders, and sampling must ensure the collection of representative and optimal intestinal samples. The aim of this paper is to focus on the diagnostic approach, from sampling to the aetiological diagnosis, of enteric disorders in pigs due to different pathogens during the different phases of production.

Cystoisospora suis infection in suckling piglets in Brazil: Prevalence and associated factors

Piglet coccidiosis is a parasitic disease caused by the protozoan Cystoisospora suis, which is regarded as the most prevalent gastrointestinal parasite in intensive pig farms. Despite the availability of highly effective chemo-metaphylaxis (toltrazuril), coccidiosis is still prevalent in European and other countries. We conducted a cross-sectional study on swine farms in Brazil, to assess the prevalence of Cystoisospora suis in fecal samples and determined the associated factors. In total, 666 litters from 50 farms were sampled twice within one week between samplings (mean age at sampling: 10.75 and 17.7 days). Of 666 litters, 225 (33.8%) were positive at least once, and the expected within farm prevalence of C. suis oocysts was 32.9% (25.4-41.3%; 95% confidence interval). Oocysts were more prevalent in fecal samples collected from farms with diarrhea (odds ratio = 6.75). The room temperature was also positively associated with oocyst detection; a one-degree increase in room temperature increased the chance of a litter being positive by 23.2%. Up-to-date, this is the most comprehensive technical evidence of factors associated with C. suis infection in Brazilian industrial piglet farms.

Prevalence of Eimeria Spp. Among Goats in China: A Systematic Review and Meta-Analysis

Eimeria spp. infection can cause weight loss in goats, and severe cases can lead to the death of lambs, resulting in economic losses to the goat industry. To explore the pooled prevalence of Eimeria spp. in goats in China, we obtained 70 related publications from five databases and conducted a meta-analysis. In China, the combined prevalence of Eimeria spp. in goats was 78.7% (95% confidence interval (CI): 68.15–87.67). Among them, the most serious infections occurred in Northeast China (88.0%, 95% CI: 83.54–91.86). The main Eimeria species were E. alijevi (43.7%, 95% CI: 29.53–58.45), E. arloingi (49.7%, 95% CI: 34.83–64.49), E. christenseni (41.2%, 95% CI: 27.07–56.16), and E. ninakohlyakimovae (35.9%, 95% CI: 21.02–52.31). In the sampling year subgroup, 2006 or later presented a lower prevalence (75.3%, 95%CI: 58.72–88.72). In terms of age, the point estimate for young goats (≤ 1 year) was higher (89.9%, 95% CI: 80.82–96.48). The Float (NaCl) method showed the lowest prevalence of Eimeria spp. in goats (75.9%, 95%CI: 62.00–87.46). In the season subgroup, the highest prevalence was in summer (81.5%, 95%CI: 49.62–99.18). Female goats presented a higher prevalence of Eimeria spp. infection than male goats (70.7%, 95%CI: 27.90–98.96). The prevalence was lower in the intensive feeding model (77.4%, 95%CI: 66.56–86.67) and higher in free feeding goats (79.4%, 95%CI: 66.46–89.92). In addition, we also analyzed the potential relationship between geographical factors and the prevalence of Eimeria spp. infection in goats in China. Our findings suggested that Eimeria spp. infection in goats is widespread in China. Despite the overall downward trend, this infection cannot be ignored. We recommend that breeders use anticoccidial drugs to prevent and treat this disease, while improving the feeding conditions and managemental practices to reduce the economic losses caused by Eimeria infection to the goat industry.