[Objective] To investigate the effects of gonadotropin-inhibitory hormone （GnIH） on feed intake, body weight and blood glucose homeostasis in male mice. [Method] A total of 20 male mice of similar weights and days of age were randomly divided into a control group （n=10） which received an intraperitoneal injection of 100 μL physiological saline per time per mouse, and an experimental group （n=10） which received an intraperitoneal injection of 20 μg/100 μL GnIH with 100 μL per time per mouse. The mice received the intraperitoneal injection of physiological saline or GnIH twice a day for consecutive 21 days. The feed intake of the mice were observed and recorded, and their weights, fasting blood glucose, glucose tolerance and insulin tolerance were determined. In addition, quantitative PCR （qPCR） was used to assess the mRNA relative expression levels of insulin transcription factor gene （NeuroD1）, insulin gene （Ins）, glucagon gene （Gcg） and insulin transcription regulative factor gene （Pdx1） in pancreas of the mice. [Result] Compared with the control group, the average daily gain and average daily feed intake of the experimental group were extremely significantly （P<0.01） higher. The area under the curve （AUC） of fasting blood glucose test, the AUC of glucose tolerance test and the AUC of insulin tolerance test of the experimental group all increased extremely significantly （P<0.01). In the experimental group, significantly （P<0.05） higher mRNA relative expression level of Gcg gene in pancreas was observed, while the significantly （P<0.05） lower mRNA relative expression levels of Ins, Pdx1 and NeuroD1 genes were found. [Conclusion] Chronic intraperitoneal injection of GnIH caused increased feed intake and body weight as well as disordered blood glucose in male mice.

[Objective] To evaluate the protective effects of total flavonoids from Spatholobus suberectus Dunn （TFSD） on liver injury induced by cyclophosphamide （CTX） in mice.[Method] A total of 60 Kunming mice were randomly divided into 1 of 6 groups with 10 mice in each group. The experimental period lasted for 7 days. The control group received physiological saline throughout the whole experiment. The CTX group was gavaged with physiological saline from 1^st to 4^th day of the experiment, and was intraperitoneally injected with 80 mg/（kg·BW） CTX once a day from 5^th to 7^th day of the experiment. TFSD100 group, CTX+TFSD25 group, CTX+TFSD50 group and CTX+TFSD100 group were gavaged with 100, 25, 50 and 100 mg/（kg·BW） TFSD once a day from 1^st to 7^th day of the experiment, respectively. From 5^th to 7^th day of the experiment, all the other experimental groups received intraperitoneal injections of 80 mg/（kg·BW） CTX once a day, with the exception of the TFSD100 group, which received intraperitoneal injections of physiological saline. At the end of the experiment, the mice in each group were sacrificed and their blood samples were taken from the eyeballs. The activities of superoxide dismutase （SOD）, myeloperoxidase （MPO）, xanthine oxidase （XOD）, and glutathione peroxidase （GSH-Px） in liver tissues were tested. In addition, the serum activities of aspartate aminotransferase （AST）, alanine aminotransferase （ALT） and alkaline phosphatase （ALP） as well as the serum levels of tumor necrosis factor-α （TNF-α）, interleukin-6 （IL-6） and interleukin-1β （IL-1β） were measured. [Result] CTX significantly （P<0.05） decreased the activities of SOD and GSH-Px in liver tissues and the serum activity of ALT, while significantly （P<0.05） elevated the activities of XOD and MPO in liver tissues, the serum activity of ALP, and the serum levels of IL-1β and IL-6. The treatments of 25, 50 and 100 mg/（kg·BW） TFSD all significantly （P<0.05） inhibited the decrease of SOD activity induced by CTX, and 25 mg/（kg·BW） TFSD significantly （P<0.05） elevated the GSH-Px activity in CTX treated mice. The treatment of 50 mg/(kg·BW) TFSD significantly （P<0.05） inhibited the elevation of XOD and MPO activities induced by CTX, and significantly （P<0.05） reduced the AST activity in CTX treated mice. The treatments of 25, 50 and 100 mg/（kg·BW） TFSD all significantly （P<0.05） inhibited the increase of ALP activity induced by CTX, and reduced the ALT activity. The treatments of 25, 50 and 100 mg/（kg·BW） TFSD all significantly （P<0.05） inhibited the increase of IL-1β level induced by CTX. [Conclusion] TFSD exhibited protective effects on cyclophosphamide induced liver injury by regulating the release of inflammatory factors and the levels of oxidoreductase in liver tissues in mice. The recommended dose of TFSD was 25 mg/（kg·BW）.

[Objective] To identify the B-cell epitope peptide of porcine epidemic diarrhea virus （PEDV） S2 gene by combinative use of bioinformatics software and monoclonal antibody technology. [Method] The B-cell epitope of PEDV S2 gene was screened using CLC Sequence viewer 6.8 software and IEDB online database, and the obtained epitope peptide was synthesized artificially. Female BALB/c mice were immunized with the conjugate of epitope peptide and keyhole hemocyanin （KLH） as antigen. Mice with higher antibody titers were identified by ELISA assay and then received an additional immunization. The spleen of the mice was taken 3 days post immunization to prepare the splenocyte suspension for cell fusion. The cells were grown on HAT selective medium to screen for effective hybridoma cells. The positive clones screened by ELISA assay were then used for expanding culture. Positive hybridoma cells were intraperitoneally injected to mice and ascites were collected. ELISA assay was used to determine the antibody titers in mice ascites and in the supernatants of monoclonal cell strains. The cells with the highest antibody titers was used as cell strain for subsequent use. [Result] The selected B-cell epitope peptide sequence was MQYVYTPTYYML. Following immunization with the peptide antigen, the serum antibody titer before cell fusion reached 1:2 000. The ELISA assay of ascites from BALB/c mice and the supernatants from monoclonal cell strain cultures demonstrated that the antibody titer reached 1:4 000. [Conclusion] The B-cell epitope of PEDV S2 gene was identified, which may be helpful for the vector construction of a epitope based peptide vaccine against PEDV.

Immunoglobulin E （IgE） - mediated allergic disorders can be treated with allergen-specific immunotherapy （ASIT）. Adjuvants and immunomodulators were utilized by researchers to improve the efficacy and safety of ASIT. CpG-oligodeoxynucleotide （CpG-ODN） is one of the best immunomodulators for the treatment of allergic disorders due to its ability to promote immunological tolerance. The doses of CpG-ODN were found to be critical for promoting immune regulation through the recruitment of plasmacytoid dendritic cells （pDCs）. Low doses of CpG-ODN elicited inflammatory responses while high doses of CpG-ODN triggered immunological tolerance. CpG-ODN has potential for the prevention and treatment of IgE-mediated allergic disorders. This paper reviews the research progress of the types of CpG-ODN, their effects on immune cells, and the mechanism of CpG-ODN as ASIT immunological tolerance inducer, in hoping to serve as references for related researches.

[Objective] To assess the effects of different wilting time and ensiling time on fermentation quality of whole plant corn silage. [Method] The silage corn Zea mays L. var. Quchen 9 was used as raw material of ensiling experiment. At late milky ripeness stage, the whole plant silage corn was harvested and crushed, and was subsequently wilted in the shade for 0 （CK）, 1, 2, 3 and 4 days respectively before being ensiled in separate plastic barrel with volume of 5 L. The fermentation quality was evaluated after 60, 90 and 120 days of ensiling. [Result] The moisture content of corn silage decreased with the extension of wiling time, and the corn silage prepared with raw material wilted for 2, 3 and 4 days had significantly （P<0.05） lower moisture content than CK. The pH value of corn silage prepared with raw material wilted for 2, 3 and 4 days was significantly （P<0.05） higher than that of CK, with the exception of wilted for 2 days and ensiled for 120 days. Wilting time exhibited significant （P<0.05) effects on the contents of lactic acid, butyric acid, neutral detergent fiber （NDF） and acid detergent fiber （ADF）, whereas ensiling time only significantly （P<0.05） affected the contents of lactic acid and butyric acid. In addition, lactic acid content increased with the prolongation of ensiling time, and butyric acid content increased after the raw material being wilted. In CK, corn silage ensiled for 90 and 120 days had significantly （P<0.05） higher NDF concentrations in comparision to that ensiled for 60 days. The fermentation quality of corn silage was diminished as a result of wilting in V-Score analysis using ammoniacal nitrogen, acetic acid, propionic acid, and butyric acid as evaluative indicators. The corn silage prepared with crushed raw material without being wilted （CK） had better fermentation quality. [Conclusion] Corn silage has better performance in comprehensive fermentation quality when the raw material is ensiled for 60 days without wilting. It is not recommended to reduce the moisture content by wilting after crushing and then ensiles when the moisture content of raw material is 74%.

Gut flora is a complex ecosystem composed of microorganisms, which can convert the nutrients that enter the intestine into substances required for the healthy growth and development of body. Gut flora plays a key role in maintaining the normal substance digestion, nutrient absorption, energy conversion and metabolic process of the animals. Numerous studies have been conducted recently on the influence and mechanism of gut flora on animal bone growth. The impact and mechanism of gut flora on bone metabolism were reviewed from the perspectives of its role in nutrient absorption, immune and endocrine functions of animals, and the effects of its metabolites, in hoping to serve as a guide for the prevention and treatment of animal bone diseases.

Probiotics are living microbial feed supplement that not only improve production performance, boost immunity, maintain gastrointestinal flora balance, clean the gastrointestinal environment, but also play an important role in preventing and treating diarrhea and regulating host immune function in animals. Probiotics can be utilized as replacement for antibiotics because of their high-level safety, no residue and no drug resistance. In equine animals, probiotics have been frequently employed and show promising outcomes. This paper provided a summary for the action mechanism of probiotics and related active substances, as well as the current issues and application prospects of equine probiotics, in hoping to serve as a guide for the development and application of equine probiotics.

[Objective] To elucidate the differences in microbial diversity between rumen and small intestine of Tan sheep lambs. [Method] Healthy weaned Tan sheep male lambs were selected and slaughtered, and the ruminal, duodenal, jejunal and ileac contents were sampled. The microbial composition and diversity of rumen and small intestine were assessed using 16S rDNA high-throughput sequencing. [Result] The Chao1 index of duodenal samples was higher than that of ruminal, jejunal and ileac samples, and the Shannon index and Simpson index of ruminal samples were higher than those of the other parts, although the difference was not statistically significant （P>0.05）. The relative abundance of Bacteroidetes, Spirochaetae and Fibrobacteres in ruminal fluid was significantly （P<0.05） higher than that in duodenum, jejunum and ileum. The relative abundance of Euryarchaeota in duodenum had an increasing trend compared with that in rumen（0.05<P<0.10）. The relative abundance of Firmicutes in jejunum and ileum was significantly （P<0.05） higher than that in duodenum. In rumen, the relative abundance of unidentified bacteria group, Rikenellaceae_RC9_gut_group, Treponema_2, Ruminococcaceae_NK4A214_group and Prevotellaceae_UCG-001 was significantly （P<0.05） higher than that in duodenum, jejunum and ileum. The relative abundance of Family_ⅩⅢ_AD3011_group in jejunum was significantly （P<0.05） higher than that of the other parts. [Conclusion] The rumen of Tan sheep lambs contained a richer diversity of bacteria, and these bacteria differed greatly from those found in duodenum, jejunum and ileum.

A significant portion of agricultural carbon emissions are caused by animal husbandry. In this study, the application of current market-oriented tools for reducing carbon emissions in animal husbandry is reviewed together with the research progress made in this area. In order to serve as a guide for animal husbandry carbon emission reduction to participate in carbon market trading, this paper presents the research status as well as the feasibility and existing difficulties of market-oriented tools for carbon emission reduction in animal husbandry such as carbon tax and carbon market trading, and summarizes the application practice and experience of those tools.

[Objective] To assess the value of the feed enterprises in China and promote their long-term development. [Method] An appraisal model for green economic value added （EVA） was created to evaluate the value of the feed enterprises in China. The green EVA was obtained by calculating the traditional EVA and adjusted green EVA of the feed enterprises from the year of 2016 to 2020. Based on the green EVA of the feed enterprises, the green EVA in the high-speed growth stage and the steady growth stage were forecasted and discounted to the benchmark date. The appraisal value was obtained by adding up the initial investment capital of the feed enterprises on benchmark date and the present value of future green EVA. [Result] From the year of 2016 to 2020, the actual ecological efficiency of the feed enterprises was higher than the expected ecological efficiency, and the environmental benefits were prominent. The annual green EVA for the feed enterprises was positive in more than 60% of cases and delivered good value. There were differences in green EVA changing trend among the feed enterprises. The value of 85% of the feed enterprises exceeded their market value, and was underestimated. However, there were huge value gaps among the feed enterprises, which was detrimental to the long-term development of feed industry. [Conclusion] The green EVA value of the feed enterprises performed well, and the economic and environmental benefits were excellent with adequate developmental potential. However, the value gaps among the feed enterprises were wide.

[Objective] To conduct an empirical research on the development of forage industry in China using alfalfa as an example from the perspective of food security, and to provide references for resolving the contradiction between people and animals for grain, achieving the balance between supply and demand of feed grain, and guaranteeing grain security. [Method] The gray correlation method was used to empirically analyze the influencing factors of feed grain growth. The influencing factors of feed grain period-by-period growth were used as the subsequence, and the feed grain period-by-period growth was used as the parent sequence to establish an analytical model. According to the ranking of correlation degree, the major factors influencing feed grain growth were determined. [Result]The correlation degree of the period-by-period growth of total output value in animal husbandry, the period-by-period growth of main livestock products, the period-by-period growth of perennial forage planting area and the period-by-period growth of annual forage planting area with the period-by-period growth of feed grain were 0.949, 0.893, 0.858, 0.831, and 0.551, respectively. This indicated that there were strong correlation between the growth of feed grain and the total output value in animal husbandry, the main livestock products and the perennial forage planting area. Furthermore, the growth of animal husbandry and feed grain were closely related, and the development of perennial forage industry could alleviate the rising demand for feed grain in China. [Conclusion] The results obtained in this study may provide empirical support and reference for the development alfalfa forage industry and the formulation of related policies in China.

[Objective] To investigate the correlation of body weight, carcass weight, and body measurement of Wuliangshan sooty chicken of different genders. [Method] A total of 60 18-week-old Wuliangshan sooty chickens with half males and half females were chosen, and their body weight, carcass weight, body oblique length, keel length, tibia length, tibia circumference, hip width, chest width, and chest depth were measured. An independent sample t-test was used for statistical comparison. For correlation analysis, Pearson analysis was employed. [Result] The males had extremely significantly （P<0.01） higher body weight, carcass weight, body oblique length, keel length, tibia length, tibia circumference, hip width, chest width, and chest depth than those of the females. Extremely significantly （P<0.01） positive correlations between body weight and carcass weight, keel length, tibial circumference were found in the males. The females′ body weight had extremely significantly （P<0.01） and significantly （P<0.05） positive correlation with carcass weight and tibial circumference, respectively. [Conclusion] The male Wuliangshan sooty chicken had much higher body weight and measurement than the female ones. Body weight was positively correlated to carcass weight and tibial circumference. Selected body measurement associated with bone development, such as keel length, tibial length and tibial circumference, had certain correlation.

[Objective] To determine the effects of feeding frequency on daily behaviors of multiparous and primiparous lactating Holstein cows. [Method] A total of 28 healthy Holstein cows, 14 multiparous and 14 primiparous, with approximately 100 days in milk （DIM） were randomly selected. They were assigned to 1 of 2 groups with 7 multiparous and 7 primiparous individuals for each group. The group 1 fed thrice a day and the group 2 fed twice a day. The daily behaviors such as feed intake, lying in bedding, lying in playfield, standing in bedding, standing in playfield, standing in passage, drinking at trough, using body brushing, and licking salt brick were observed for 5 consecutive days, and the daily occurring frequency and duration of the behaviors were recorded and statistically compared between the two groups. [Result] For both multiparous and primiparous lactating cows, when the feeding times changed from thrice a day to twice a day, the occurring frequency and duration of daily feed intake was significantly （P<0.05） reduced, while the duration of daily total lying （in bedding and playfield） was significantly （P<0.05） increased. With either feeding thrice a day or twice a day, the duration of daily lying in bedding, lying and standing in bedding and licking salt brick in multiparous lactating cows was significantly （P<0.05） higher than that of the primiparous lactating cows, while no significant （P>0.05） differernces in occurring frequency and duration of daily feed intake, total lying （in bedding and playfield）, total standing （in bedding and playfield） and drinking at trough were observed between multiparous and primiparous lactating cows. [Conclusion] The reduction of feeding times significantly affected the occurring frequency and duration of daily feed intake as well as duration of daily total lying of multiparous and primiparous lactating cows.

[Objective] According to the characteristics of vast activity area, insensitivity to the environment and delayed movement of free range cattle population, by referring the existing animal body size measurement technology, a non-contact body size measuring system on the basis of unmanned air vehicle （UAV） off-line 3D reconstruction method capable of collecting cattle point cloud data was develped to establish a wide coverage, precise, and high-efficient cattle body size measurement solution. [Method] Firstly, a quad-axis UAV was used to capture images, and some image processing techniques such as noise reduction with median filter and image three-channel histogram equalization were utilized to preprocess the image and to improve the reconstructed point cloud density and measurement accuracy. Secondly, the aerial triangulation measurement was conducted using the position and orientation system （POS） information from the image, and the 3D model was reconstructed after the initial coordinate data of point cloud was confirmed by adjustment computation. Finally, the point cloud of individual cattle was extracted by using random sample consensus （RANSAC） algorithm in point cloud library （PCL） and then interactive measurement was made. [Result] Images from 4 cattle herds and 1 individual cattle were collected, and available point cloud of body size data from a total of 21 cattle were reconstructed. In comparision to the convetional manual measurement method, the average relative errors in body height, body length and chest circumference measured by the developed UAV based system were 3.87%, 4.16% and 5.06%, respectively. [Conclusion] The UAV based system developed in this study can be used to measure body size of medium- and low-density free range cattle herds in Inner Mongolia, and the error is within the acceptable range.

[Objective] To investigate the effects of different saline-alkali stresses on germination of wild soybean seeds collected in Hinggan League of Inner Mongolia, and to provide references for the development and utilization of high-quality wild soybean germplasm resources. [Method] Wild soybean seeds were treated with saline or alkali stresses using NaCl solution （20, 40, 80 and 120 mmol/L）, Na₂SO₄ solution （10, 20, 30 and 40 mmol/L）, and Na₂CO₃ solution （20, 40, 60 and 120 mmol/L）, respectively, and the seeds with no saline-alkali stress treatments were served as control group （CK）. Three replicates were set for each concentration of each solution, with 50 seeds per replicate. The seed germination rate, germination potential, germination index, vigour index, relative injury rate, as well as the seedling root length and seedling length of the seeds treated with the above three solutions were determined and statistically compared. [Result] When the wild soybean seeds were treated with NaCl solution, the highest germination rate, germination potential, germination index and vigour index as well as the lowest relative injury rate were observed in 80 mmol/L treatment group; the seedling root length and seedling length decreased with the increase of NaCl concentrations; the seedling root length and seedling length of 80 and 120 mmol/L treatment groups were significantly （P<0.05） lower than those of 20 and 40 mmol/L treatment groups. When the wild soybean seeds were treated with Na₂SO₄ solution, the highest germination rate, germination potential, germination index and vigour index as well as the lowest relative injury rate were found in 30 mmol/L treatment group; the seedling root length and seedling length decreased with the increase of Na₂SO₄ concentrations; the seedling root length and seedling length in 10 mmol/L treatment group were the longest, with no significant （P>0.05） difference compared to CK. When the wild soybean seeds were treated with Na₂CO₃ solution, the germination rate, germination potential, germination index and vigour index gradually decreased with the increase of Na₂CO₃ concentrations, while the relative injury rate exhibited the adverse trend; the germination rate, germination potential, germination index and vigour index in 120 mmol/L treatment group were 0, and the relative injury rate was 100%; there was no significant （P>0.05） differences in germination rate, germination potential, germination index and vigour index between 20 mmol/L treatment group and CK. [Conclusion] Low intensity of saline-alkali stresses minorly affected the germination indexes of wild soybean seeds collected in Hinggan League, and a certain range of intensities of weak alkali or neutral salt were capable of promoting their germination; different intensities of saline-alkali stresses had an effect on the growth traits of wild soybean seedling, the higher the concentrations, the greater the damages.

[Objective] To gather information on the research status and the hot spots of zoonosis and zoonotic microorganisms worldwide, and to provide references for the prevention and control of zoonotic diseases in China. [Method] COOC 12.6 and Citespace 5.8 R1 software were used to carry out frequency statistics, co-occurrence analysis, cluster analysis, timeline analysis and burst analysis on the keywords associated with zoonosis and zoonotic microorganisms in PubMed database. [Result] According to the keywords frequency statistics and co-occurrence analysis results from the year of 2001 to 2021 in pubMed database, the zoonosis and zoonotic microorganisms arousing high international attentions were classified into the following three categories: the first category was commonly observed zoonotic microorganisms such as Brucella, hepatitis E virus, Streptococcus, Escherichia coli （E. coli） and Salmonella, to which continuous public attentions were still needed to be paid; the second category was the zoonotic microorganisms worldwide concerned in recent years such as severe acute respiratory syndrome coronavirus-2 （SARS-CoV-2） and influenza A virus, which were worthy of more in-depth research to control the spread of these diseases as soon as possible; the third category was the zoonosis that had massively prevailed in specific regions abroad such as Q fever and middle east respiratory syndrome （MERS）, and these diseases were expected to be noticed in terms of imported risks to avoid their outbreaks in China. In addition to the above mentioned zoonosis and zoonotic microorganisms, some keywords associated with detection and diagnosis such as phylogeny and PCR were also of high interests. The cluster analysis generated a total of 10 clusters, in which the tick-borne infectious disease cluster suggested the role of ticks in the transmission of zoonotic diseases; the results of timeline and burst analysis demonstrated that among the zoonotic microorganisms, the attentions being paid to influenza A virus and SARS-CoV-2 were gradually increasing. At the same time, the detection technology of zoonotic microorganisms was evolving from specific sequence detection to whole genome sequencing. These fields were likely to be the research direction and trend in the future. [Conclusion] The findings in this study imply that interests in the studies on zoonosis and zoonotic microorganisms are growing, and that advances have being made in the technology used to detect these zoonotic microorganisms. In China, the prevention and control of influenza A and corona virus disease 2019 （COVID-19） should be given top priority and tick-borne infectious diseases should also receive certain attention. These information may serve as a guide for the prevention and control of zoonosis in China.

[Objective] To determine the causes of morbidity and mortality of some introduced goat kids in a large-scale dairy goat farm in Inner Mongolia, so as to provide a scientific basis for this farm to strengthen the prevention and control of major epidemic diseases. [Method] The pathological anatomy obaservation of the diseased goat kids with typical clinical signs was made. Pathological sections were prepared using aseptically collected lung samples with lesions. Serum was prepared using aseptically collected blood samples, and the goatpox virus antibody in serum was detected by high-sensitive fluorescence technology. The lung tissues as well as nasal and eye swabs were aseptically gathered, and the P32 gene of goatpox virus was detected by PCR assay and sequenced. The obtained the sequences were subjected to comparision with BLAST and homology analysis. [Result] Pathological autopsy showed that there was round pox in oral, nasal, laryngeal, and tracheal mucosa of the diseased goat kids; the lungs were obviously edematous with red pox on the surface, and were opaque and gray-white jelly like following incision; pox was also visible in the rumen, reticulum, omasum, and abomasum mucosa. Histopathologic examination revealed that the alveoli were intensely stained with red; the alveolar interstitium was widened, and the alveolar cavity contained exfoliated epithelial cells; type Ⅱ alveolar epithelial cells proliferated and had a metaplasia into acinar-like shape; there were massive inflammatory cells in the lumen of bronchi. The goatpox virus antibody in serum of the diseased goat kids was tested positive using high-sensitive fluorescence technology. Lung tissue （GTPV-YP1）, nasal swab （GTPV-YP2） and eye swab （GTPV-YP3） samples were collected, and the P32 gene of a predicted length of 983 bp was all amplified by PCR assay from these samples. The P32 gene sequences of GTPV-YP1 and GTPV-YP2 samples had 100% homology with goatpox virus Chinese isolate KC951854.1 and Oman isolate MN072621.1, and the P32 gene sequence of GTPV-YP3 sample was 99.0% homologous to goatpox virus Chinese isolates EF514892.1, HM572329.1, JN596275.1 and MG817382.1. [Conclusion] The goatpox virus infection was determined as the cause of the illness in the introduced dairy goat kids on the farm by pathological anatomy observation, histological examination, serological detection, and pathogen PCR identification.

[Objective] To investigate and analyze the parasitic infection status of thoroughbred horses of different genders and ages in varied months in Zhaosu County of Xinjiang, so as to provide guidelines for the healthy breeding and scientific deworming of the thoroughbred horses in this region. [Method] A total of 122 thoroughbred horses of different ages were randomly selected and divided into 5 groups according to genders and ages, including 30 lactating foals, 25 young mares, 20 young males, 35 breeding mares and 12 stallions. Experiments were carried out according to the modes of group confinement feeding and single stall feeding in the stable to ensure the adequate intake of diet and drinking water for the thoroughbred horses of different ages. The fecal samples were collected in May and October. By using the egg count method, the parasites in the fecal samples were detected, and the parasite infection rate and intensity of the thoroughbred horses of different ages in varied months were estimated. [Result] In May, the infection rates of Oxyuris equi and Eimeria spp in the thoroughbred horses were high, and the infection rates were all higher than 94.00% with the exception of the stallions. Among them, the infection rates of Oxyuris equi and Eimeria spp in the lactating foals were as high as 98.89% and 98.33%, respectively. The infection rates of Parascaris equorum and Eimeria spp in the thoroughbred horses were higher than 93.00% in October, with Parascaris equorum infection rates in the breeding mares reaching 99.52% and Eimeria spp infection rates in the lactating foals reaching 98.33%. In May, the lactating foals had significantly （P<0.05） higher infection intensities of Parascaris equorum, Trichostrongylus spp, Cyathostomum spp and Triodontophorus tenuicollis than the other groups, and had significantly （P<0.05） higher infection intensities of Oxyuris equi, Eimeria spp and Gastrodiscus aegyptiacus than the stallions, but no significant （P>0.05） differences with the other groups. In October, the lactating foals had significantly （P<0.05） higher infection intensities of Parascaris equorum, Trichostrongylus spp and Anoplocephala spp than the other groups except for the breeding mares, had significantly （P<0.05） higher infection intensity of Triodontophorus tenuicollis than the other groups, and had significantly （P<0.05） higher infection intensities of Eimeria spp and Gastrodiscus aegyptiacus than the stallions. The infection intensities of Parascaris equorum and Triodontophorus tenuicollis in the stallions was significantly （P<0.05） lower than the other groups. There were no significant （P>0.05） differences in the infection intensity of Oxyuris equi across the different groups. [Conclusion] The main intestinal parasites found in the thoroughbred horses in Zhaosu County were Oxyuris equi, Eimeria spp, Trichostrongylus spp, Triodontophorus tenuicollis, Cyathostomum spp, Parascaris equorum, Anoplocephala spp, and Gastrodiscus acgyptiacus. The single infections and severe co-infections of the above parasites occurred in the thoroughbred horses of different ages and in varied months. The lactating foals had higher parasitic infection rates and intensities than the thoroughbred horses of the other ages.