犬PD-1单克隆抗体的筛选与鉴定

为筛选犬程序性死亡受体1(cPD-1)单克隆抗体,以原核表达并纯化复性的cPD-1胞外区蛋白为靶抗原免疫BALB/c小鼠,应用单克隆抗体杂交瘤细胞技术和间接ELISA方法,经3轮轮筛选和克隆化,获得1株能稳定分泌抗cPD-1单克隆抗体的杂交瘤细胞株1F9。间接ELISA检测显示1F9杂交瘤细胞株连续传代培养能稳定分泌单克隆抗体,效价达到1∶2048,亚型鉴定重链为IgG1,轻链为κ;以HEK293细胞表达cPD-1胞外区蛋白为检测抗原,Western-blot和间接免疫荧光试验进行鉴定,结果显示1F9单克隆抗体能特异性结合cPD-1胞外区蛋白。本研究通过小鼠杂交瘤技术成功筛选到1株鼠源cPD-1单克隆抗体。     

Genetic diversity in Trypanosoma theileri from Sri Lankan cattle and water buffaloes

Trypanosoma theileri is a hemoprotozoan parasite that infects various ruminant species. We investigated the epidemiology of this parasite among cattle and water buffalo populations bred in Sri Lanka, using a diagnostic PCR assay based on the cathepsin L-like protein (CATL) gene. Blood DNA samples sourced from cattle (n = 316) and water buffaloes (n = 320) bred in different geographical areas of Sri Lanka were PCR screened for T. theileri. Parasite DNA was detected in cattle and water buffaloes alike in all the sampling locations. The overall T. theileri-positive rate was higher in water buffaloes (15.9%) than in cattle (7.6%). Subsequently, PCR amplicons were sequenced and the partial CATL sequences were phylogenetically analyzed. The identity values for the CATL gene were 89.6–99.7% among the cattle-derived sequences, compared with values of 90.7–100% for the buffalo-derived sequences. However, the cattle-derived sequences shared 88.2–100% identity values with those from buffaloes. In the phylogenetic tree, the Sri Lankan CATL gene sequences fell into two major clades (TthI and TthII), both of which contain CATL sequences from several other countries. Although most of the CATL sequences from Sri Lankan cattle and buffaloes clustered independently, two buffalo-derived sequences were observed to be closely related to those of the Sri Lankan cattle. Furthermore, a Sri Lankan buffalo sequence clustered with CATL gene sequences from Brazilian buffalo and Thai cattle. In addition to reporting the first PCR-based survey of T. theileri among Sri Lankan-bred cattle and water buffaloes, the present study found that some of the CATL gene fragments sourced from water buffaloes shared similarity with those determined from cattle in this country.     

Variation of serum inorganic phosphorus and association with haemoglobinuria and osteomalacia in female water buffaloes in Pakistan

Data from an animal health service in the Punjab of Pakistan showed that 39 adult female buffaloes with haemoglobinuria were 21 times more likely to have serum inorganic phosphorus (serum P) levels < 0.97 mmol/1 than 24 controls sampled during the period of case occurrence (December 1984–March 1985). Age > 7 years or early lactation (1–60 days post partum) were unrelated to the disease. Similarly, symptoms of osteomalacia in 19 multiparous buffaloes were associated with low P (OR = 14.3) but not with age. Subsequently, a serum survey was carried out from February 1985 to July 1987 to investigate serum P variations with season and host factors. Data from 139 farms (426 adult female buffaloes, 468 lactations) indicated strong farm and seasonal effects on serum P. Serum P declined during the study period and was lowest during December–March 1985/1986 and again 1986/1987. Calving season, parity > 1, high pregnancy > 6 months, or daily milk production were not related to serum P in the final model. Seasonal effects were interpreted as soil borne and related to feed changes from maize to berseem in December.     

Genetic analysis of river,swamp and hybrid buffaloes of north‐east India throw new light on phylogeography of water buffalo (Bubalus bubalis)

This study analysed buffaloes from north‐east India and compared their nuclear and mitochondrial DNA variations with buffaloes of mainland India, China, Mediterranean and South‐East Asia. Microsatellite genotypes of 338 buffaloes including 210 from six north‐east Indian buffalo populations and three mainland Indian breeds were analysed to evaluate their genetic structure and evolutionary relationships. Phylogenetic analysis and multidimensional scaling plot of pairwise F_ST revealed the clustering of all swamp‐type buffaloes of north‐east India with Lower Assamese (significantly hybrid type) buffaloes in one plane and all the mainland river buffaloes in another plane while the upper Assamese buffaloes being distinct from both these clusters. Analysis of mtDNA D‐loop region of 530‐bp length was performed on 345 sequences belonging to 23 buffalo populations from various geographical regions to establish the phylogeography of Indian water buffalo. The swamp buffaloes of north‐east India clustered with both the lineages of Chinese swamp buffalo. Multidimensional scaling display of pairwise F_ST derived from mitochondrial DNA data showed clustering of upper Assamese, Chilika and Mediterranean buffaloes distinctly from all the other Indian buffalo populations. Median‐joining network analysis further confirmed the distinctness and ancestral nature of these buffaloes. The study revealed north‐east region of India forming part of the wider hybrid zone of water buffalo that may probably extend from north‐east India to South‐East Asia.     

Comparative molecular characterization of Forkhead box protein 3 (FoxP3) gene of swamp-type (Bubalus carabanensis) and riverine-type (Bubalus bubalis) water buffaloes

FoxP3 is a forkhead family member that plays an important role in the development and function of a type of CD4 + T cell called T regulatory cells. Molecular characterization of FoxP3 gene in swamp- and riverine-type water buffaloes was conducted to determine its homology and compare it to the FoxP3 gene of other animal species (cattle, goat, sheep, horse, pig, cat, and dog), determine its unique characteristics in water buffaloes, and provide a reference for future studies to analyze its immunological function. FoxP3 nucleotide sequence of swamp- and riverine-type water buffaloes was 99% identical, whereas its protein translation revealed 97% homology. FoxP3 of swamp- and riverine-type water buffaloes were compared to FoxP3 of other animal species and revealed a high degree of homology which suggests that they may have the same biological properties. This study is the first report that describes the genetic characteristic of FoxP3 gene in water buffalo.     

Antibodies against bovine herpesvirus 4 are highly prevalent in wild African buffaloes throughout eastern and southern Africa

Bovine herpesvirus 4 (BoHV-4) has been isolated from cattle throughout the world. Interestingly, a survey of wild African buffaloes mainly from the Maasai Mara Game Reserve in Kenya revealed that 94% of the animals tested had anti-BoHV-4 antibodies [Rossiter, P.B., Gumm, I.D., Stagg, D.A., Conrad, P.A., Mukolwe, S., Davies, F.G., White, H., 1989. Isolation of bovine herpesvirus-3 from African buffaloes (Syncerus caffer). Res. Vet. Sci. 46, 337–343]. These authors also proposed that the serological antigenic relationship existing between BoHV-4 and alcelaphine herpesvirus 1 (AlHV-1) could confer to BoHV-4 infected buffaloes a protective immune response against lethal AlHV-1 infection. In the present study, we addressed two questions related to Rossiter et al. paper. Firstly, to investigate the role of the African buffalo as a natural host species of BoHV-4, the seroprevalence of anti-BoHV-4 antibodies was analysed in wild African buffaloes throughout eastern and southern Africa. A total of 400 sera was analysed using two complementary immunofluorescent assays. These analyses revealed that independently of their geographical origin, wild African buffaloes exhibit a seroprevalence of anti-BoHV-4 antibodies higher than 68%. This result is by far above the seroprevalence generally observed in cattle. Our data are discussed in the light of our recent phylogenetic study demonstrating that the BoHV-4 Bo17 gene has been acquired from a recent ancestor of the African buffalo. Secondly, we investigated the humoral antigenic relationship existing between BoHV-4 and AlHV-1. Our results demonstrate that among the antigens expressed in AlHV-1 infected cells, epitope(s) recognised by anti-BoHV-4 antibodies are exclusively nuclear, suggesting that the putative property of BoHV-4 to confer an immune protection against AlHV-1 relies on a cellular rather than on a humoral immune response.     

Increased expression of the regulatory T cell-associated marker CTLA-4 in bovine leukemia virus infection

Regulatory T cells (Tregs) play a critical role in the maintenance of the host's immune system. Tregs, particularly CD4⁺CD25⁺Foxp3⁺ T cells, have been reported to be involved in the immune evasion mechanism of tumors and several pathogens that cause chronic infections. Recent studies showed that a Treg-associated marker, cytotoxic T-lymphocyte antigen 4 (CTLA-4), is closely associated with the progression of several diseases. We recently reported that the proportion of Foxp3⁺CD4⁺ cells was positively correlated with the number of lymphocytes, virus titer, and virus load but inversely correlated with IFN-γ expression in cattle infected with bovine leukemia virus (BLV), which causes chronic infection and lymphoma in its host. Here the kinetics of CTLA-4⁺ cells were analyzed in BLV-infected cattle. CTLA-4 mRNA was predominantly expressed in CD4⁺ T cells in BLV-infected cattle, and the expression was positively correlated with Foxp3 mRNA expression. To test for differences in the protein expression level of CTLA-4, we measured the proportion of CTLA-4-expressing cells by flow cytometry. In cattle with persistent lymphocytosis (PL), mean fluorescence intensities (MFIs) of CTLA-4 on CD4⁺ and CD25⁺ T cells were significantly increased compared with that in control and aleukemic (AL) cattle. The percentage of CTLA-4⁺ cells in the CD4⁺ T cell subpopulation was positively correlated with TGF-β mRNA expression, suggesting that CD4⁺CTLA-4⁺ T cells have a potentially immunosuppressive function in BLV infection. In the limited number of cattle that were tested, the anti-CTLA-4 antibody enhanced the expression of CD69, IL-2, and IFN-γ mRNA in anti-programmed death ligand 1 (PD-L1) antibody-treated peripheral blood mononuclear cells from BLV-infected cattle. Together with previous findings, the present results indicate that Tregs may be involved in the inhibition of T cell function during BLV infection.     

鸡PD-1单克隆抗体的制备及生物学功能研究

试验旨在筛选并制备鸡PD-1单克隆抗体,对该单克隆抗体的免疫学特性、结合活性及其对鸡PD-1/PD-L1信号通路激活的阻断作用进行初步研究。运用杂交瘤细胞融合技术筛选杂交瘤细胞株,采用ELISA方法、Ig抗体亚型鉴定试剂盒、Western blotting鉴定抗体的免疫学特性,利用间接免疫荧光技术及流式细胞术检测筛选单抗与鸡PBMCs的结合情况,应用该单抗与IBDV感染7 d后的鸡PBMC细胞作用,利用实时荧光定量PCR技术检测IL-2、IL-6和IFN-γ等细胞因子的表达情况。结果显示,试验获得1株特异、稳定分泌鸡PD-1单克隆抗体的杂交瘤细胞株,命名为PD-1-D05。该单克隆抗体的亚型属于IgG1,杂交瘤细胞培养上清和腹水的效价分别为1：2¹¹和1：2.048×10⁵。ELISA和Western blotting检测结果表明,PD-1-D05单抗能与免疫原发生特异性反应,与pET-28a （+）、Rosetta菌株蛋白提取液上清及无关蛋白无交叉反应。间接免疫荧光及流式细胞术检测结果显示,PD-1-D05单克隆抗体能与鸡PBMC特异性结合,且IBDV感染7 d后的PBMC经单抗处理后,IL-2表达量显著升高（P<0.05）,IFN-γ转录水平显著下降（P<0.05）,IL-6表达水平较IBDV攻毒组细胞虽有所下降,但并无统计学差异（P>0.05）。结果表明,试验成功筛选并制备了能够稳定分泌鸡PD-1单克隆抗体的细胞株,所获得的PD-1单克隆抗体具有良好的免疫学特性,该单抗能够特异性识别鸡PD-1分子并与鸡PBMC细胞特异结合,并在一定程度上恢复由于IBDV感染导致的PD-1/PD-L1信号通路激活引发的免疫调节相关细胞因子IL-2、IFN-γ的异常表达。     

PD-1 and PD-L1 regulate cellular immunity in canine visceral leishmaniasis

PD-1 is a negative costimulator of chronic infectious diseases In this study, we investigated the expression of PD-1 and its ligands in the spleen of dogs with visceral leishmaniasis and lymphoproliferative response to soluble antigen, in lymph node cells in the presence or absence of antibodies blocking PD-1 and its ligands. Our results showed expression of PD-1 and its ligands is higher after L. infantum infection and in the spleen of infected dogs, PD-1 blockage was able to restore the antigen-dependent lymphoproliferative response and regulated production of the cytokines IL-4 and IL-10 and NO production. We concluded that L. infantum infection modulates PD-1 and its ligands expression in canine VL and that blockage of PD-1 restores the immune response. Thus, blockage of PD-1 is a target for therapeutic drug development.     

Isolation of two cDNAs encoding MHC-DQA1 and -DQA2 from the water buffalo, Bubalus bubalis

In the present study, we explored structural and functional variations and possible duplication of the major histocompatibility complex (MHC)-DQA gene in water buffalo (Bubalus bubalis). Two cDNA sequences, amplified from one individual water buffalo, were designated as Bubu-DQA1 (DQA*0101) and -DQA2 (DQA*2001). The percentage of nucleotide and amino acid similarity between Bubu-DQA1 and -DQA2 revealed that these sequences display more similarity to alleles of respective DQA1 and DQA2 genes from other ruminant species than to each other. The phylogenetic analysis also revealed a considerably larger genetic distance between these two genes than between homologous genes from other species. The larger genetic distance between DQA*0101 and DQA*2001, and the presence of different bovine DQA putative locus specific amino acid motifs, suggests these sequences are non-allelic. This finding is consistent with DQA gene duplication in other ruminants.     

广西沼泽型水牛IL-4和IL-5基因的克隆及其序列分析

从刀豆素A(Concanavalin A,ConA)刺激的广西沼泽型成年水牛外周血单个核细胞(Peripheralblood mononuclear cells,PBMCs)中提取总RNA,用逆转录聚合酶链式反应(RT-PCR)方法扩增出白细胞介素-4(Interleukin-4,IL-4)和白细胞介素-5(IL-5)基因,分别克隆到pMD18-T载体上,进行序列分析。结果表明,从培养9 h、17 h的单个核细胞中扩增得到的IL-4基因在核苷酸水平上与GenBank上登录的印度水牛IL-4 cDNA序列同源性为98.8%,与牛、绵羊、猪和马的同源性分别为99.3%、94.1%、84.8%和80.6%;氨基酸水平的同源性分别为96.3%、98.5%、90.4%、78.4%和59.6%。从培养12 h的单个核细胞中扩增得到的IL-5基因在核苷酸水平上与GenBank上登录的牛、绵羊、猪和马IL-5 cDNA序列同源性分别是99.0%、96.5%、89.6%和89.1%;氨基酸水平的同源性分别为97.8%、96.2%、85.9%和86.7%。本研究为进一步了解水牛IL-4和IL-5的结构和水牛免疫学特性奠定了基础。     

苏皖水牛肝片吸虫和前后盘吸虫感染情况的调查

苏皖两省１０县（市）共调查３０２农户的３０７头水牛,粪便学检查肝片吸虫阳性４３头,阳性率１４．０％,其中安徽的阳性率为１１．６１％（１８／１５５）,江苏阳性率为１６．４８％（２５／１５２）;母牛阳性率为１１．８％,公牛为１１．４％;前后盘吸虫阳性１７０头,阳性率为５５．４％（１７０／３０７）,其中安徽的阳性率为５８．１％（９０／１５５）;江苏的阳性为５２．６％（８０／１５２）,母牛的阳性率为６０．１％（１３７／２２８）,公牛的阳必国４１．８％（３３／７９）,两种吸虫的阳性率均呈现随年龄增加而提高的趋势,经统计学分析,两种吸虫的感染与地形无显著差异（Ｐ〉０．０５）,肝片吸虫的感染与性别、年龄亦无显著差异（Ｐ〉０．０５）,但对前后盘吸虫来说,感染与性别、年龄的差异显著（Ｐ〈０．０５）。而各县间两种吸虫感染则有显著关     

Prevalence of antibodies against Bubaline herpesvirus (BuHV-1) among Mediterranean water buffalo (Bubalus bubalis) with implications in buffalo trade

Background: Both Bovine herpesvirus (BoHV-1) and Bubaline herpesvirus (BuHV-1) have been reported to cross the species barrier. Antibody seroconversion in glycoprotein E (gE) blocking ELISA during BuHV-1 infection has been documented. Recent diagnostic efforts have focused on the development and application of discriminatory tests to distinguish between infections with BoHV-1 and BuHV-1.

Objective: To evaluate the impact and distribution of these two infections in water buffalo farms in two regions (Piedmont (n = 3) and Campania (n = 10), Italy) where infectious bovine rhinotracheitis control programs have been implemented.

Animals and methods: Sampling was carried out on 13 buffalo farms comprising 1089 animals using specific gE-indirect ELISA's test able to discriminate among BoHV-1 and BuHV-1 infections.

Results: 59.0% of animals reacted positive to ELISA (irrespective of whether BoHV-1 or BuHV-1 antigen was used) and 86.4% of these were reactive to BuHV-1 only, whereas 11.8% showed absorbance values for both antigens and were classified as inconclusive. There was a statistically significant age-related difference in BuHV-1 infection rates but not in overall individual (47% vs. 58%) or herd prevalence (100% vs. 90%) of infection between the two regions.

Conclusion: The low percentage of sera reactive to BoHV-1 (1.8%, 12/643) indicates that BuHV-1 may be the main circulating alphaherpesvirus infection in Mediterranean water buffalo in the two study areas. Since Bubalus bubalis is included in Directive 64/432/EEC on animal health problems affecting intra-community trade in bovine animals, diagnostic testing with nonspecific ELISA for BoHV-1 infection in buffalo may yield false-positive reactions. This scenario could lead to economic losses and hamper buffalo trade and movement, particularly for reproduction purposes.     

Assessment of water buffalo health and productivity in a communal management system in the Philippines

This study aimed to generate a profile of the health and productivity of water buffaloes in a communal setting. Using the Epi-Info version 6.04 for data management, a coded information system was used to accommodate data coming from the reference population. Calves and cows that were born and milked, respectively, were enrolled and monitored for six months. The key outcomes of interest monitored in this study included mortality, morbidity and productivity. Results of the study showed a 93.7 percent probability of the calves surviving up to six months with a calculated mortality true rate of 0.7 deaths per 1000 calf-days at risk. Three calves died during the six month observation period with a mean age at death of 3 days. Analysis of variance on productivity showed that the parasitic load, specifically coccidia, liver fluke and trypanosoma affected the growth rate of the calves. The productivity of cows in the study in terms of milk production was also highly affected by the endoparasitic load and disease condition of the animal. Univariate analysis revealed a significant association between calf scouring and cow’s mastitis (MASTITIS)(P = 0.066). Meanwhile, for the cows, the parasitic load particularly fasciolosis (P = 0.000), coccidiosis (P = 0.002) and trypanosomosis (P = 0.094) (P < 0.10) also significantly affected the milk production. The results give a clearer view of the relationship between the health and productivity profiles of these animals.     

Effects of species and sex on plasma hormone and metabolite concentrations in crossbred Brahman cattle and crossbred water buffalo

Buffalo meat is tasty and indistinguishable from beef, and has been described as being lean and low in cholesterol in comparison with beef. However, little is known about the plasma hormone and metabolic profiles related to fat metabolism in buffalo, and how their levels are affected by species and sex. In this study levels of plasma hormones and metabolites were compared between species and sexes. Ten growing crossbred Brahman cattle and ten growing crossbred buffaloes (five males and five females in each), with an average age of 22 months were used. The animals were fed on an experimental diet composed of corn silage, brewer's spent grain and a concentrate mixture at a 50:30:20 ratio on a dry matter basis during a fattening period of 6 months. Blood samples were collected every month during the experiment, and were analysed for plasma leptin, insulin, glucose, triglyceride (TG) and total cholesterol (TC) concentrations. Plasma leptin, insulin and TC concentrations increased during fattening and were significantly (P < 0.05) higher in cattle than in buffaloes. These concentrations in cattle showed a big difference between sexes in comparison with buffaloes, and were higher in females than in males. The plasma glucose and TG concentrations did not differ (P > 0.05) between cattle and buffaloes.

The crude fat content of longissimus muscle was significantly higher in cattle than in buffalo. Differences in body fat deposition seem to have an influence on plasma leptin, insulin and TC concentrations differently between cattle and buffaloes.     

牛新孢子虫病和弓形虫病的流行病学调查

为了调查我国牛新孢子虫和弓形虫的感染情况，应用新孢子虫酶联免疫吸附试验（ELISA）和弓形虫间接血凝试验（IAT）分别检测了来自国内10个省（市、自治区）的262份乳牛、10份肉牛和40份水牛血清。结果显示，乳牛新孢子虫的抗体阳性率为17．2％，弓形虫的抗体阳性率为2．3％，没有检测到既有新抱子虫抗体又有弓形虫抗体的乳牛血清。各牛场所检乳牛血清的新孢子虫抗体阳性率在0～34．4％之间。在水牛和肉牛血清中未检测到新孢子虫抗体和弓形虫抗体。流产乳牛血清的新孢子虫抗体阳性率为20．2％，未流产乳牛为16．1％，其中血清抗体阳性乳牛主要在妊娠中晚期流产。各个年龄段乳牛血清的抗体阳性率差异不显著（P〉0．05）。不同妊娠胎次的乳牛血清抗体阳性率差异不显著（P〉0．05）。确认新孢子虫病在国内大部分牛场存在。     

Comparison of voluntary feed intake, rumen passage and degradation kinetics between crossbred Brahmam cattle (Bos indicus) and swamp buffaloes (Bubalus bubalis) fed a fattening diet based on corn silage

Three crossbred tropical cattle and three crossbred buffaloes, fitted with rumen cannulas, were used to investigate the differences in feed intake, digestibility and parameters with rumen degradation kinetics between cattle and buffalo fed a fattening diet in the Philippines. The animals were fed a diet consisting of 50% corn silage (CS), 30% brewer's grain (BG) and 20% concentrate mixture (CM) on a dry matter (DM) basis, at a level of 3% bodyweight (BW) as DM. Total DM intake (DMI) and rumen fill were greater (P < 0.05) for buffaloes than for cattle, but significant differences were not detected between the animal species when those were expressed as percentage of BW. The DMI per metabolic body size for BG and CM were greater for buffaloes than for cattle (P < 0.05), whereas that of CS did not differ between the species (P > 0.05). The weight proportion of consumed feedstuffs differed between cattle and buffaloes (P < 0.05), although nutrient intake per total DMI did not differ significantly (P > 0.05) between the animal species. Nutrients digestibility was higher (P < 0.05) for buffaloes than for cattle. Ruminal passage rate constant of feed particles and rumen fluid did not differ (P > 0.05) between the animal species. Higher DM degradation rate constant and effective degradability with CS were prominent for buffaloes than for cattle (P < 0.05). Degradation parameters did not differ (P > 0.05) between cattle and buffaloes, neither with BG nor CM. The results indicate that the greater digestibility with DM and energy for buffaloes are ascribable to greater effective degradability of CS fed ad libitum level.     

德宏水牛与尼里拉菲水牛及其杂交水牛的细胞遗传学研究

为了弄清河川型水牛与沼泽型水牛杂交后代的核型,以及与其育性和亲本核型的关系,用外周血液淋巴细胞培养法对尼里拉菲水牛、德宏水牛及尼里拉菲水牛×德宏水牛F1代公牛进行淋巴细胞培养,制作染色体标本,并进行G-带染色;利用BEION染色体核型分析系统对染色体标本分别进行染色体核型分析,确定其染色体核型。根据染色体核型分析结果,并结合其育性,分析染色体核型与其育性的关系。结果显示,尼里拉菲水牛核型为2n=50,XY;德宏水牛核型为2n=48,-4,-4,-9,-9,+t(4;9),+t(4;9),XY;尼里拉菲水牛×德宏水牛F1代公牛核型为:2n=49,-4,-9,+t(4;9),XY。     

Pharmacokinetics and distribution of ampicillin in plasma,milk and uterine fluid of female buffaloes

A pharmacokinetic study of ampicillin (6 mg/kg intravenous) revealed that the peak concentrations of 17.81±1.25, 5.64±2.24 and 1.09±0.10 g/ml of the drug were attained at 15 min, 30 min and 2 h in plasma, milk and uterine fluid respectively. A therapeutic concentration of 0.1 g/ml was maintained from 15 min–8 h, 15 min–6 h and 30 min–6 h in plasma, milk and uterine fluid. Hence, the drug may be used effectively in mammary gland and uterine infections apart from its use in other systemic infections.     

槟榔江水牛OXCT1基因的分子特征及组织表达谱分析

本研究对槟榔江水牛3-酮酸辅酶A转移酶1（3-oxoacid CoA-transferase 1,OXCT1）基因的完整CDS区进行了PCR扩增,并对其功能生物信息学和多组织差异表达进行了分析。以普通牛OXCT1基因序列（GenBank登录号：XM_006076397）为参考序列,采用Primer Premier 5.0软件设计引物序列,以提取的槟榔江水牛基因组DNA为模板,PCR扩增获得槟榔江水牛OXCT1基因mRNA序列,扩增产物经测序后利用ORF Finder软件进行开放阅读框识别,获得水牛OXCT1基因CDS区全序列,并对其进行生物信息学分析。结果显示,槟榔江水牛OXCT1基因CDS序列全长1 563 bp,编码520个氨基酸,蛋白分子式为C₂₅₀₉H₄₀₄₁N₆₈₇O₇₄₆S₂₃,分子质量为56.50 ku,理论等电点（pI）为8.69,不稳定系数为27.49,平均疏水性（GRAVY）为-0.097,该蛋白属弱亲水性蛋白。OXCT1蛋白无信号肽和跨膜结构,属于线粒体膜蛋白;包含pcaJ_scoB_fam和AtoD 2个保守结构域,且具有5个功能活性位点。槟榔江水牛与普通牛、藏羚羊等5个物种的OXCT1氨基酸序列同源性≥ 97%。对槟榔江水牛13个组织进行表达谱分析表明,在泌乳期,OXCT1基因在乳腺中表达量最高,在肾脏、垂体、脂肪、大脑、皮肤和肌肉中不表达;在非泌乳期,OXCT1基因在除脂肪以外的其他12个组织中都有表达。OXCT1基因在槟榔江水牛泌乳期乳腺组织中表达量最高,推测其可能参与了水牛的乳脂合成调控事件。本研究结果可为深入了解乳脂合成代谢及其调控机制提供依据。