Pharmacological Treatment for Atrial Fibrillation—Modalities in Equines and Companion Animals

Cardiac arrhythmias are probably more common in horses than in any other domestic animal species where poor performance and exercise intolerance is the most frequent clinical complaint. Atrial fibrillation is a type of cardiac arrhythmia that appears as a common finding during medical examinations in humans, large breed dogs and horses. Clinical presentations are of a particular value in racehorses in high performing activities. Atrial fibrillation is characterized by an irregular heart rhythm, secondary to a primary disease or without any sign of comorbidity. The generation and maintenance of Atrial Fibrillation requires a substrate. Some breeds have a genetic predisposition to developing Atrial Fibrillation. Most cases of Atrial Fibrillation are of the paroxysmal type and self-regulate within a few hours to days without the need for treatment. The focus of this study is on the arrhythmic agents that are used for the treatment of Atrial Fibrillation, therefore other arrhythmic agents may not be included, or are included to demonstrate their effect on increasing, inhibiting or decreasing efficacy when used together with medications for the treatment of Atrial Fibrillation. The “working horse” for the pharmacological treatment of Atrial Fibrillation is Quinidine.

Establishment of Fluorescence Quantitative RT-PCR Assay for Detection of Equine Arteritis Virus

[Objective]The paper was to establish a fluorescence quantitative RT-PCR method for detection of equine arteritis virus(EAV).[Method]Primers and probes were developed for the EAV ORF7 gene sequence,and the reaction system was optimized.Standard curves were established,leading to the initial development of the EAV fluorescence quantitative RT-PCR assay.The accuracy,specificity,and sensitivity of this method were subsequently evaluated.[Result]The EAV fluorescence quantitative RT-PCR assay demonstrated optimal performance at an annealing temperature of 61 C,with a final concentration of primer and probe set at 0.6μmol/L.The plasmid standard demonstrated a strong linear correlation with Ct values within the range of 1.6×10^(7)-1.6×10^(2)copies/μL.The equation of the standard curve was determined to be y=-2.68x+32.88,with an R^(2) value of 0.9927.Consequently,the EAV fluorescence quantitative RT-PCR assay was successfully established.The methodology employed was effective in detecting EAV,Theileria equi,equine herpesvirus-1(EHV-1),equine herpesvirus-4(EHV-4),and equine influenza virus(EIV).The findings indicated that the method was specifically capable of detecting EAV,while the other pathogens tested yielded negative results.The method demonstrated a high degree of specificity.It was employed to detect the standard plasmid cRNA synthesized through in vitro transcription following a 10-fold dilution.The results indicated that the minimum detection limit of the method was 1.6×10^(2) copies/μL,and it exhibited high sensitivity.The coefficient of variation,both within and between groups,was maintained at 1.8%,indicating good reproducibility.In this study,the fluorescence quantitative RT-PCR assay developed was utilized alongside the EAV fluorescence quantitative RT-PCR assay established by previous researchers to analyze a total of 234 clinical samples.Both methods yielded a positive detection rate of 14.1%,and the coincidence rate between the two techniques was found to be 100%.[Conclusion]The fluorescence quantitative RT-PCR assay developed in this study offers a novel approach and concept for the prevention and control of equine viral arteritis(EVA).

Double Arthrodesis, Postero-Medial Release and Posterior Tibial Transfer in One Step in Paralytic Inveterate Equine Varus Foot

Introduction: Varus equine foot deformity is common in developing countries. The management of these deformities is surgical in adults. Several surgical techniques have been described with more or less satisfactory results. To our knowledge, no study has been performed on the simultaneous association of double arthrodesis, posteromedial release, and posterior tibial transfer in a single operation in inveterate paralytic varus equines feet. The purpose of this work was to evaluate the results obtained. Patients and Method: This was a retrospective descriptive study from January 01, 2018 to December 31, 2021. It concerned inveterate paralytic varus equines feet operated on by the simultaneous association in a single operative time of double arthrodesis of the foot, posteromedial release of the back foot and transfer of the posterior tibial muscle to the lateral cuneiform. We identified seven patients with a mean age of 22.1 years with extremes of 11 years and 36 years. There were three males and four females. The cause of the deformity was neurological in all cases. All patients had painful walking discomfort and shoeing difficulties. The average time to management was 13.3 years with extremes of 4 and 25 years. The chronology of the interventional steps was posteromedial release, arthrodesis, and transfer of the posterior tibial muscle to the lateral cuneiform. The average postoperative follow-up was 21.7 months with extremes of 6 and 48 months. The parameters studied were the duration of the procedure, complications related to the procedure, muscle strength at the last recoil, consolidation of the arthrodesis, residual pain, patient activity, gait perimeter, stepping, ankle mobility, residual deformity, footwear, protrusion of the transferred tendon, and the possibility of walking on the heel. Final results were graded according to the Angus and Cowell criteria. Results: No intraoperative complications were noted. An early superficial infection of the surgical site was noted. It was treated with local care and healed without sequel. Residual pain was present in one case. Tibiotalar osteoarthritis was observed in one case, which required a tibiotalar arthrodesis. At the last follow-up, consolidation of the arthrodesis was effective in all patients. The posterior tibial muscle was side 5 (n = 4) and 4 (n = 3). The patients’ activity was normal without assistance in all cases. The walking perimeter was greater than 1 km in six patients. Patient activity was normal without assistance in all cases. Stepping was absent in all patients. No difficulty with footwear was noted. According to the Angus and Cowell criteria, the result was good (n = 6), i.e. 85.7% and bad (n = 1), i.e. 14.3% of cases. Conclusion: This study suggests that double arthrodesis associated with posteromedial release and transfer of the posterior tibial in one step in inveterate paralytic varus equines feet, gives satisfactory results. It allows for easy shoeing and plantigrade walking without stepping. Complications are essentially represented by the absence of fusion of the arthrodesis and tibiotalar arthrosis.

马流感病毒(A/equine/Qinghai/1/94)核蛋白基因的序列测定及同源性分析

根据已发表的马流感病毒核蛋白基因序列 ,设计并合成一对特异性引物 ,经反转录_聚合酶链反应 (RT_PCR)成功扩增出了我国马流感病毒 (A/Equine/Qinghai/ 1/ 94 )核蛋白基因 ,将该片段连接到PGEM_T_EASY载体并转化DH5α ,提取阳性菌落的质粒经EcRo1酶切和PCR鉴定其大小为 1.5kb左右 ,对其测序并进行分析发现 ,与A/Equine /Kentucky/2 / 86、A/Equine/Miami/ 1/ 6 3等关系较近 ,同源率为 93.3%～_97.4 % ,而与我国马流感吉林A/Equine/Jilin/ 1/ 89株关系较远 ,同源率仅为 84 .6 %。

马流感病毒(A/Equine/Qinghai/1/94)神经氨酸酶基因的克隆与同源性分析

本试验根据已发表的马流感病毒神经氨酸酶 (NA)基因序列 ,设计并合成一对特异性引物 ,经反转录_聚合酶链反应 (RT_PCR)成功扩增出了我国马流感病毒青海株 (A/Equine/Qinghai/1/94 )NA基因 ,将片段连接到PGEM_T_easy载体并转化DH5α ,提取阳性菌落的质粒经EcRo1酶切和PCR鉴定其大小均为 1.4Kb左右 ,对其测序并构建NA基因进化树。经过比较分析发现 ,我国马流感病毒青海株与A/Equine/Alaska/1/91、A/Equine/Tennessee/5 /86和A/Equine/Algiers/72等关系较近 ,核苷酸同源率为 98.2 %～ 97.4 % ;与我国马流感吉林株 (A/Equine/Jilin/1/89)关系较远 ,核苷酸同源率仅为72 .0 % ;而与H7N7亚型马流感病毒A/Equine/Prague/1/5 6核苷酸同源率仅为 38.0 %。

广西马流感病毒(A/Equine/Guangxi/1/09)NA基因的克隆与序列分析

【目的】了解广西马流感病毒（Equine influenza virus,EIV）的分子流行病学特征并揭示其遗传变化规律,为其疫苗候选毒株的筛选及有效防控马流感疫情奠定基础。【方法】采用RT-PCR对广西EIV分离株（A/Equine/Guangxi/1/09,简称GX09株）进行NA基因扩增,经克隆测序及序列比对分析,绘制遗传进化树。【结果】GX09株NA基因全长1420 bp,其开放阅读框（ORF）为1413 bp,编码470个氨基酸,包含7个糖基化位点及17个半胱氨酸（Cys）残基。GX09株与参考毒株的NA基因核苷酸同源性为74.7%~99.5%,其推导氨基酸同源性为80.4%~99.4%;与Gansu08株、Heilongjiang08株、Inner mongolia08株及Liaoning08株的核苷酸及其推导氨基酸同源性最高,分别为99.5%和99.4%;与1989年在我国吉林分离获得毒株（Jilin89）的同源性最低,对应的核苷酸及其推导氨基酸同源性分别为74.7%和80.4%。从遗传进化树可以看出,GX09株与最近几年国内外分离获得的毒株亲缘关系较近,且同属于美洲型分支。【结论】目前广西流行的EIV与国内外的流行毒株一致。

Culture conditions for equine bone marrow mesenchymal stem cells and expression of key transcription factors during their differentiation into osteoblasts

Background： The use of equine bone marrow mesenchymal stem cells （BMSC） is a novel method to improve fracture healing in horses. However, additional research is needed to identify optimal culture conditions and to determine the mechanisms involved in regulating BMSC differentiation into osteoblasts. The objectives of the experiments were to determine： 1） if autologous or commercial serum is better for proliferation and differentiation of equine BMSC into osteoblasts, and 2） the expression of key transcription factors during the differentiation of equine BMSC into osteoblasts. Equine BMSC were isolated from the sterna of 3 horses, treated with purchased fetal bovine serum （FBS） or autologous horse serum （HS）, and cell proliferation determined. To induce osteoblast differentiation, cells were incubated with L-ascorbic acid-2-phosphate and glycerol-2-phosphate in the presence or absence of human bone morphogenetic protein2 （BMP2）, dexamethasone （DEX）, or combination of the two. Alkaline phosphatase （ALP） activity, a marker of osteoblast differentiation, was determined by ELISA. Total RNA was isolated from differentiating BMSC between d 0 to 18 to determine expression of runt-reloted tronscrJption foctor2 （Runx2）, osterix （Osx）, and T-box3 （Tbx3）. Data were analyzed by ANOVA. Results： Relative to control, FBS and HS increased cell number （133 ± 5 and 116 ± 5%, respectively; P 〈 0.001） and 5-bromo- 2＇-deoxyuridine （BrdU） incorporation （167 ± 6 and 120 ± 6%, respectively; P 〈 0.001）. Treatment with DEX increased ALP activity compared with control （1,638 ± 38%; P 〈 0.001）. In the absence and presence of Dex, BMP-2 did not alter ALP activity （P 〉 0.8）. Runt-reloted transcription foctor2 expression increased 3-fold （P 〈 0.001） by d 6 of culture. Osterix expression increased 94old （P 〈 0.05） by d 18 of culture. Expression of Tbx3 increased 1.8-fold at d 3 （P 〈 0.01）; however expression was reduced 4-fold at d 18 （P 〈 0.01）. Conclusions： Dexamethasone, but not BMP-2, is required for differentiation of equine BMSC into osteoblasts. In addition, expression of Runx2 and osterix increased and expression of Tbx3 is reduced during differentiation.

A Review: Interactions of Equine Herpesvirus-1 with Immune System and Equine Lymphocyte

Equine herpesvirus-1 (EHV-1) remains one of the most common viral pathogens affecting horses worldwide presenting as a persistent infection which can establish latency in nerve ganglia (trigeminal ganglion), lymphoid tissues of the respiratory tract and peripheral blood lymphocytes. EHV-1 infection induces both humoral and cellular immune responses in horses. Virus neutralising antibody, particularly in the nasopharynx, is to kill free virus shed from infected epithelial cells. Hence this antibody has important functions in reducing virus shedding and spreading infection to cohorts. Cellular immune responses, particularly those carried out by cytotoxic T lymphocyte (CTL), have been shown to be effective in killing virus-infected cells in vitro. This review underlines the state of knowledge regarding immunity to EHV-1 and also its interaction with equine lymphocyte. Finally, the review also includes the importance of the viral immediate early (IE) protein in the pathogenesis of EHV-1. This information can be used as the basis for future research.

Fast and Sensitive Chiral Analysis of Amphetamines and Cathinones in Equine Urine and Plasma Using Liquid Chromatography Tandem Mass Spectrometry

A simple, rapid, sensitive and reproducible method for enantiomer analysis of methamphetamine, amphetamine, cathinone and methcathinone was developed and validated. The compounds were extracted from equine plasma and urine using a fast liquid-liquid extraction procedure. Only one milliliter plasma and one hundred microliter urine sample is needed for analysis. The extraction procedure had good recovery (>70%) and the matrix effect was negligible. Enantiomer differentiation and confirmation were achieved using liquid chromatography with chiral stationary phase and mass spectrometry detection. The method demonstrated excellent reproducibility with intra-day and inter-day precision of lower than 5%. The lower limits of detection for all of the compounds studied here were at low pg/mL level for both plasma and urine. This is the first report of the analysis of four chiral compounds in equine plasma and urine. Routine application was demonstrated for (S)- and (R)-enantiomer differentiation.

The Comparison of Genetic Variation in the Envelope Protein Between Various Immunodeficiency Viruses and Equine Infectious Anemia Virus

The envelope protein （Env） of lentiviruses such as HIV, SIV, FIV and EIAV is larger than that of other retroviruses. The Chinese EIAV attenuated vaccine is based on Env and has helped to successfully control this virus, demonstrating that envelope is crucial for vaccine. We compared Env variation of the four kinds of lentiviruses. Phylogenetic analysis showed that the evolutionary relationship of Env between HIV and SIV was the closest and they appeared to descend from a common ancestor, and the relationship of HIV and EIAV was the furthest. EIAV had the shortest Env length and the least number of potential N-linked glyeosylation sites （PNGS） as well as glyeosylation density compared to various immunodefieiency viruses. However, HIV had the longest Env length and the most PNGS. Moreover, the alignment of HIV and SIV showed that PNGS were primarily distributed within extraeellular membrane protein gp120 rather than transmembrane gp41. It implies that the size difference among these viruses is associated with a lentivirus specific function and also the diversity of env. There arc low levels of modification of glycosylation sites of Env and selection of optimal protective epitopes might be useful for development of an effective vaccine against HIV/AIDS.

Evolutionary Patterns of the Proviral gp90 V3 to V5 Regions of Equine Infectious Anemia Virus Associated with Immune Selection in Progressors and Nonprogressors

The aim of this study was to determine the genomic evolutionary pattern of virulent equine infectious anemia virus （EIAV） during persistent infection. The evolutionary dynamics of proviral genomes were examined by challenging an EIAV seronegative equine （pony 1） and three EIAV vaccinated equines （ponies 4, 7, and 8） with the Chinese virulent strain EIAV- L. Ponies 1 and 7 succumbed to disease and were called progressors, while ponies 4 and 8 lacked clinical symptoms and were considered nonprogressors. Sequences spanning the V3, V4, and V5 hyper-variable regions of the EIAV-L envelope gp90 gene were sequenced from each pony as evolutionary markers of the provirus. The proviral genome of the EIAV-L inoculum evolved during persistent infection and displayed different patterns between EIA progressors and nonprogressors. Inoculum-like variants were isolated from nonprogressors during persistent infection, but only from progressors during acute infection. Variant mutations from nonprogressors were dispersed throughout the sequenced region, while those from progressors were predominantly localized to V3. Humoral immunity and virus variant population selection analyses indicated that immune selection was positive in chronically infected progressors and weak in nonprogressors. In-frame stop codons were frequently localized to a defect ＂hot spot＂. The high number of defective variants in nonprogressors may promote disease survival.

Complete Sequence of Proviral DNA of Equine Infectious Anemia Virus Strain L

Equine infectious anemia virus strain L (EIAV-L) is the parental virulent virus of equine infectious anemia donkey leukocyte attenuated vaccine (DLA EIAV). In this study, peripheral blood leukocytes(PBL) were collected from a horse infected with EIAV-L.The PBL DNAs were extracted.The EIAV-L proviral DNA was amplified in four parts covering the entire proviral genomic sequence by polymerase chain reaction (PCR). Each of the four parts was cloned into the plasmid pBluescript SK, and the recombinant plasmids were designated as p2.8, p2.4. p3.1, and p1.2 respectively. After identification with restriction digestion, the inserts within the four plasmids were sequenced. The complete nucleotide sequence of EIAV-L provirus was determined by analyzing each of the four parts and connecting them as a whole. The genome of EIAV-L is 8235 bp in length, and G + C content is 38%. The comparison analysis by the computer software DNASIS showed that the sequence of EIAV-L shares 98.4% and 96.9% identities with that of D-A EIAV and DLA EIAV respectively. The high homology between these strains showed that they were genetically related. The homology between EIAV-L and D-A EIAV is higher than that between EIAV-L and DLA EIAV, and this is consistent with the derivation progress of DLA EIAV. At both ends of EIAV-L provirus, there is an identical long terminal repeat (LTR) sequence of 316bp in length. The LTR consists of U3, R, and U5 regions. The genome of EIAV-L provirus has three long open reading frames(ORF) corresponding to gag, pol and env genes respectively. The gag gene is 1200bp and located at position 613-1912nt. The pol gene is 3402bp and located at position 1708-5109nt. There is a termination codon within the env dividing it into two parts, envl of 699bp (position 5305-6003nt)and env2 of 1827bp (position 6073-7899nt). The provirus has three additional small ORFs: S1, S2 and S3 with sizes of 153bp(position 5113-5265nt), 204bp(position 5279-5482nt)and 402bp(position 7245-7646nt) respectively.

Changes of Biomarkers in Synovial Fluid in Equine OA Model

The pathogenesis of equine Osteoarthritis（OA） is more complex, and the disease in the early stage is not easy to be found, therefore, the early diagnosis and treatment are very important. Based on this, this experiment established OA model induced by equine, aimed to study the changes of contents of Matrix Metalloproteinases-3（MMP-3）, Matrix Metalloproteinases-13（MMP-13）, Aggrecanase（ADAMTS-5）, Hyaluronic Acid（HA） and Osteocalcin（OCN） in synovial fluid, and establish rapid diagnostic technique for the equine OA. Thirteen Mongolian equines were used in these induction studies. Equines were randomly divided into two groups： the experimental group contained eight equines and the control group contained five equines. The experimental group was to build the equine osteoarthritis model. The induction was done through Intra-articular（IA） injection of 2 m L Amphotericin-B in equines’ left carpal joints. The equine of the control group was injected into 2 m L physiological saline in equines’ left carpal joints. Synovial fluid was collected every week until the 9th week. The contents of MMP-3, MMP-13, ADAMTS-5, HA and OCN in synovial fluid were evaluated by using ELISA kits. Equine OA model, compared with the control group, starting from the 1st to the 2nd week after induction model, the content of MMP-3, MMP-13, ADAMTS-5, HA and OCN tended to increase, but there was no significant increase, from the 2nd to the 3rd week they significantly increased（p〈0.05） and kept increasing trend until the 9th week. In OA model, MMP-3, MMP-13, ADAMTS-5, HA and OCN showed a rising trend in joint fluid, which would accelerate the cartilage, subchondral bone degradation and metabolism of these proteases increased, and ADAMTS-5 and HA in the early stage increased significantly.

Epidemiological Study on Equine Gastrointestinal Helminth Parasites in Mekelle, North Ethiopia

A cross-sectional examination of 384 fecal samples was conducted from July 2016 up to November 2016 to determine the prevalence of gastrointestinal helminth infections of equines in Mekelle, North Ethiopia. Out of total fecal samples examined 196 fecal samples were taken from horses, 164 from Donkeys and the rest 24 from Mules. The prevalence of gastro intestinal helminths was 41.6% as detected by coprological examination. Coprological examination revealed that the prevalence in horses was 33.7%, in donkeys 51.8% and in mules 37.5%. There is significant difference (p < 0.05) in the prevalence of GIT helminth infection between the equine species. Coprological examination revealed 35.4% infection with strongyle followed by mixed infections (10.4%), P. eqourum (8.3%), O. equi (5.7%) and Anoplocephala species (4%). No significant difference (p > 0.05) in prevalence of GIT helminth was noticed between sexes. However, a significant difference (p < 0.05) was noticed between the age groups, between different body conditions, feeding status, history of colic and frequency of deworming. The study revealed that Equines in the study area are infected with a range of heminths, which are representatives of the important equine pathogenic parasites found in Ethiopia.

Phylogenetic analysis of the five internal genes and evolutionary pathways of the Greek H3N8 equine influenza virus

To amplify the NS, NP, PB1, PB2 and PA internal genes of two equine H3N8 influenza A viruses isolated in Greece in 2003 and 2007 five primer pairs were designed. The derived sequences were analysed from a phylogenetic point of view and compared with the evolutionary patters of the HA and NA proteins. Comparison of nucleotide sequences of the five internal genes of the Greek strains showed high similarity (99.3% - 99.7%) to strains isolated from outbreaks in Europe and Asia during 2002-2008. A total of 11 amino acid substitutions of the surface protein NA and the RNP complex proteins were identified in the Greek strains compared to those of progenitor viruses circulating up to 2003. These substitutions were repeated in Chinese and Mongolian isolates from outbreaks in 2007-2008. Notably NS1 protein did not acquired amino acid substitutions and moreover, a stop codon introduced at position 220 was stably maintained in the Greek strains. Phylogenetic trees of the five internal genes did not show the same separation in clades. Greek strains classified them into the American sublineage (as for the PA) Florida clade II (as for the NP, NS1 and PB1) and among Chinese strains of 2007-2008 outbreaks (as for the PB2). Additionally, evolutionary profiles of these internal proteins, except PB2, indicated a parallel evolution fashion to the HA protein, suggesting the possible occurrence of genetic reassortment between H3N8 viruses of district evolutionary lineages. In conclusion, phylogenetic analysis of the internal genes reported in this study could establish a candidate framework for future scientific communications on the phylogenetic diversity and evolution of the equine influenza viruses.

Selection of Reference Genes in Equine White Blood Cells for Real Time PCR Normalization Following Extracorporeal Shock Wave Therapy

Selection of proper reference genes (RGs) is an essential step needed for accurate normalization of results from genomic studies. Expression of RGs is regulated by many factors such as species, age, gender, type of tissue, the presence of disease, and the administration of therapeutic treatment. The aim of the present study was to identify optimal RGs in a set of blood samples collected at different time points (0, 24, 48, 72 h) from horses following administration of extracorporeal shock wave therapy (ESWT). The mRNA expression of twelve RGs: HPRT1, ACTB, HSP90A, SDHA, GUSB, B2M, UBC, NONO, TBP, H6PD, RPL32, GAPDH was determined using real time quantitative polymerase chain reaction (qPCR). An SAS program developed on the algorithm of geNorm, SASqPCR, was used to determine stability of the expression and the number of optimal RGs. The results showed that the range of quantification cycle (Cq) values of the evaluated genes varied between 17 and 26 cycles, and that one optimal RG, ACTB, was sufficient for normalization of gene expression. Results of stability of expression demonstrated that ACTB was the optimal choice for all the samples studied. Notably, in samples collected at 72 h post ESWT, TBP showed a significant change in the expression level, and was not suitable for use as a RG. These results substantiate the importance of validating and selecting an appropriate RG.

Doping Control Analysis of 16 Non-Steroidal Anti-Inflammatory Drugs in Equine Plasma Using Liquid Chromatography-Tandem Mass Spectrometry

Non-steroidal anti-inflammatory drugs (NSAIDs) are classified as Class 4 agents by the Association of Racing Commissioners International and are banned in racehorses during competition in Pennsylvania (PA). To control the abuse of these agents in racehorses competing in PA, a forensic method for screening and confirmation of the presence of these agents is needed. Equine plasma (0.5 mL) was acidified with 75 μL 1M H3PO4 to increase recovery of the analytes by liquid-liquid extraction using methyl tert-butyl ether (MTBE). Extracted analytes were separated by reversed-phase liquid chromatography using a C8 column under gradient condition. All 16 analytes were detected, quantified and confirmed using a triple quadrupole tandem mass spectrometry with selected reaction monitoring (SRM) in both negative and positive electrospray ionization modes. The limit of detection, quantification and confirmation of the analytes were 1.0 - 5.0 ng/mL, 1.0 - 5.0 ng/mL and 1.0 - 20 ng/mL, respectively. The linear dynamic range of quantification was 5.0 - 200 ng/mL. The method is routinely used in anti-doping analysis to control the abuse of NSAIDs in racehorses competing in PA.

Immune Control of Equine Infectious Anemia Virus Infection by Cell-Mediated and Humoral Responses

Equine Infectious Anemia Virus (EIAV) is a retrovirus that establishes a persistent infection in horses and ponies. The virus is in the same lentivirus subgroup that includes human immunodeficiency virus (HIV). The similarities between these two viruses make the study of the immune response to EIAV relevant to research on HIV. We developed a mathematical model of within-host EIAV infection dynamics that contains both humoral and cell-mediated immune responses. Analysis of the model yields results on thresholds that would be necessary for a combined immune response to successfully control infection. Numerical simulations are presented to illustrate the results. These findings have the potential to lead to immunological control measures for lentiviral infection.

Risk Assessment and Comprehensive Control of Insect and Wild Animal Vectors in the Prevalence of Related Equine Diseases in the Specific Equine Disease-free Zone of Guangzhou Asian Games

[ Objective] In order to construct the specific equine disease-free zone of of the Guangzhou Asian Games, to ensure that the equestrian events of Guangzhou Asian Games be smoothly held. [Methods] The species, quantities, distribution and seasonal variations of insects and wild animals in related zones were investigated from 2008 to 2010, and the collected samples of the insects and wild animals were tested in laboratory for related equine diseases. [Results] The investigations indicated that there were some mosquitoes, flies, horseflies, punkies, ticks, bats, wild birds and wild bears in equastrianism venue and peripheral regions of disease-free zone of the Guangzhou Asian Games, the laboratory results of Japa- nese encephalitis, vesicular stomatitis, Nipah virus disease, West Nile fever, and Trypanosomiasis evansi, were all negative. According to the in- vestigations and test results, the risk assessments of insect and wild animal vectors in the prevalence of related equine diseases were made to con- firm that the risk was relatively low or very low, and comprehensive prevention and control measures with prevention as major measures and insecti- cides application and environment managements as supplementary means were made on the basis of the risk assessment conclusions. [ Conclu- sions] This research has laid a solid foundation for the successful building of the first specific equine disease-free zone in our country, ensured the smooth holding of the 16th equastdan competition in Guangzhou Asian Games.

Effects of equine-assisted interventions on older adults’health:A systematic review

Objective:Equine-assisted interventions(EAI)can improve a variety of health problems in older adults and thus promote their well-being.This systematic review aimed to synthesize studies on EAI to understand better their effects on the health of older adults.Method:A systematic search guided by the PRISMA 2020 approach was performed on specific databases:Medline(PubMed),EMBASE,PsycINFO,and Cochrane Library.Peer-reviewed articles published in the English language from inception to June 2022 were retrieved.Methodological quality was established using the modified version of the Downs and Black checklist.Results:A total of 244 studies were retrieved,and 13 eligible studies were finally included.Three health domains were investigated:physical(balance,gait,and muscular strength),psychological(quality of life and cognitive assessment),and physiological(hormonal measures,cerebral and muscular activity).Among the eight studies investigating the physical dimension,four studies highlighted a positive effect of EAI on balance,four for gait,and three for strength.Regarding the three studies investigating the psychological dimension,two studies showed a positive effect of EAI on quality of life.Lastly,the four studies investigating the physiological dimensions all demonstrated a positive effect of EAI on hormonal measures and cerebral and muscular activity.Conclusion:Nevertheless,this systematic review provides promising findings regarding the positive effects of EAI on physical,psychological,and physiological health in older adults.Research on EAI should therefore be pursued rigorously to promote this non-pharmacological intervention in an older adult population.