Blastocystis is an enteric protozoan able to infect humans and a large variety of animal hosts worldwide. It exhibits significant genetic diversity, with at least 17 subtypes (STs) identified to date, most of which have low host specificity. In the present study, a cross-sectional survey was conducted on Blastocystis infection among humans and domestic animals sharing habitats in northeastern China\'s Heilongjiang Province, in order to investigate the frequency and subtype distribution and to evaluate the risk of the zoonotic transmission of Blastocystis sp..Results show that the frequency was 10.5% (6/57), and three subtypes (ST1, ST2, and ST3) were found in humans; in animals, the frequency was 17.9% (46/257), and six subtypes (ST1, ST3, ST5, ST7, ST10, and ST26) were detected. A significant association between Blastocystis sp. infection and eating unwashed vegetables and fruits was found (P = 0.007). We found no effect on gender, age and season on Blastocystis sp. colonization. Phylogenetic analysis showed that Blastocystis ST7 sequences from chicken in two geographical locations formed two distinct clades. Alleles were identified using the Blastocystis 18S database, and a total of 10 different alleles were found in seven STs. Overlap of STs in humans and domestic animals (pig or cattle) was observed in Dongfanghong village. The findings of potentially zoonotic subtypes in domestic animals suggest that these animals may serve as reservoirs of human Blastocystis sp. infections. Multisectoral cooperation is needed to slow down the transmission of Blastocystis in domestic animals, minimize environmental contamination by Blastocystis cysts, and increase molecular epidemiological surveillance of Blastocystis sp. in humans and animals.

Fertility refers to the ability of animals to maintain reproductive function and give birth to offspring, which is an important indicator to measure the productivity of animals. Fertility is affected by many factors, among which environmental factors may also play key roles. During the past years, substantial research studies have been conducted to detect the factors related to fecundity, including genetic factors and environmental factors. However, the identified genes associated with fertility from countless previous studies are randomly dispersed in the literature, whereas some other novel fertility-related genes are needed to detect from omics-based datasets. Here, we constructed a fertility index factor database FifBase based on manually curated published literature and RNA-Seq datasets. During the construction of the literature group, we obtained 3301 articles related to fecundity for 13 species from PubMed, involving 2823 genes, which are related to 75 fecundity indicators or 47 environmental factors. Eventually, 1558 genes associated with fertility were filtered in 10 species, of which 1088 and 470 were from RNA-Seq datasets and text mining data, respectively, involving 2910 fertility-gene pairs and 58 fertility-environmental factors. All these data were cataloged into FifBase (http://www.nwsuaflmz.com/FifBase/), where the fertility-related factor information, including gene annotation and environmental factors, can be browsed, retrieved and downloaded with the user-friendly interface.

Blastocystis is a common intestinal protozoan parasite of humans and a variety of animal species. To date, the prevalence of Blastocystis and major subtypes distribution in the domestic animals inhabiting in the Qinghai-Tibetan Plateau Area (QTPA) of China is yet poorly studied. In this study, we investigated the distribution and genetic diversity of Blastocystis in seven animal species in QTPA in China. Four hundred and five fresh fecal samples were collected from domestic animals in Qinghai, Yunnan, and Tibet of China and analyzed using nested PCR and SSU rRNA gene sequencing. It was found that the overall prevalence of Blastocystis infection was 40.2% (163/405) in the animals studied. The most predominant subtype of Blastocystis was ST10 (57.7%) followed by ST14 (28.8%) and ST2 (13.5%). These results reveal the epidemiological features of Blastocytis infection in animals in the high altitude plateau area. The finding of presence of ST2 in a number of animal species suggests a zoonotic nature of Blastocystis and might be of importance of public health.

Schistosomiasis japonica, caused by Schistosoma japonicum, is an endemic, zoonotic parasitic disease. Domestic animals, particularly bovines, are thought to play an important role in transmission of the disease. Historically, China was the country mostly severely impacted by schistosomiasis japonica, but now prevalence and morbidity have been greatly reduced. Since the mid-1950s when China launched the National Schistosomiasis Control Program, the control of schistosomiasis in domestic animals has been carried out almost synchronously with that of human schistosomiasis, and this concept has been proven to be effective. Generally, the campaign of schistosomiasis japonica control in domestic animals in China went through four phases over the past six decades, namely, the large-scale epidemiological investigation phase, the case screening and small-scale chemotherapy phase, the mass chemotherapy phase, and the infection source control phase. These distinct phases were responsive to changing disease epidemiology, socioeconomic development, and technological advances, resulting in successful attainment of disease control goals.

Schistosomiasis japonica is a major public health problem in China. Domestic animals play a major role in the transmission of Schistosoma japonicum to humans. To better understand the epidemiology of schistosomiasis japonica in domestic animals in the mountainous areas of China, we performed a 5-year longitudinal study of schistosomiasis in cattle and horses in Yunnan Province from 2009 to 2013. We also performed a concurrent drug-based intervention study in three settlement groups in Yunnan Province aimed at developing an effective means of controlling transmission in this region. The prevalence of infection in cattle fluctuated between 1.67% and 3.05% from 2009 to 2011, and monthly treatments of schistosome-positive animals reduced the prevalence to 0% (P<0.05) from 2012 to 2013. Prior to the intervention, we found that schistosomiasis was prevalent from May to October, with the highest prevalence observed in June (10.00%). We surveyed for environmental schistosome contamination, and 94.29% of the miracidia found were from cattle. Our study showed that it is possible to eliminate schistosomiasis in domestic animals in the mountainous regions of China by monthly treating cattle and horses from schistosome-positive households from May to October.

Echinococcosis is highly endemic over large parts of the Qinghai-Tibet Plateau (QTP), China. Based on a large number of samples, we present data on the current presence, host distribution, and genetic diversity of Echinococcus in the Qinghai Province, located in the northeastern corner of the QTP and constituting >25% of the area of the plateau. We used 521 samples (including 451 newly collected samples and 70 samples from our previous study) from humans, yaks, sheep, goats, dogs, fox, plateau pikas, and voles in 36 counties, and genotyped them using the mitochondrial DNA marker cytochrome oxidase subunit I (cox1) gene and the maximum parsimony and Bayesian reconstruction methods. Based on the 792 bp sequence matrix, we recorded 177 variable sites; 157 were parsimony-informative. A total of 105 haplotypes (H1-H105) were detected, of which H1-H15 and H90-H104, H16-H17, H18-H89, and H105 belonged to Echinococcus shiquicus, Echinococcus multilocularis, Echinococcus granulosus, and Echinococcus canadensis, respectively. Our results showed that, (i) the Qinghai Province was under a high burden of Echinococcus epidemiology; (ii) E. granulosus was the main echinococcosis threat to the local people, and the followed is E. multilocularis; (iii) there are a considerable number of haplotypes shared by domestic animals (sheep, yaks, and dogs) and humans, demonstrating the close relationship between human and domestic animals epidemiology; (iv) the threat of E. shiquicus on humans and livestock can be mostly ignored, while the infection risk of E. canadensis echinococcosis should not be neglected.

More than 1000 complete or near-complete mitochondrial DNA (mtDNA) sequences have been deposited in GenBank for eight common domestic animals (cattle, dog, goat, horse, pig, sheep, yak and chicken) and their close wild ancestors or relatives, as well. Nevertheless, few efforts have been performed to evaluate the sequence data quality. Herein, we conducted a phylogenetic survey of these complete or near-complete mtDNA sequences based on mtDNA haplogroup trees for the eight animals. We show that errors due to artificial recombination, surplus of mutations and phantom mutations do exist in 14.5% (194/1342) of mtDNA sequences and all of them should be treated with wide caution. We propose some caveats for future mtDNA studies of domestic animals.