Preliminary findings from an experimental study of caprine besnoitiosis in Kenya

Inoculation of cystozoites obtained from natural, chronic cases of caprine besnoitiosis produced clinical disease in goats but not in rabbits, mice, guinea pigs, hamsters, rats or cattle. Histological examination of tissue sections from the experimental animals showedBesnoitia cysts only in goats. This, together with field observations that cattle reared together with goats having besnoitiosis do not contract the disease, suggests that theBesnoitia species that infects goats in Kenya is host-specific and is notBesnoitia besnoiti. We suggest that the nameBesnoitia caprae be adopted for the caprine pathogen.     

First in vitro isolation of Besnoitia besnoiti from chronically infected cattle in Germany

Besnoitia besnoiti was in vitro isolated during the first recorded outbreak of bovine besnoitiosis in Germany. Molecular characterization of the new isolate, named Bb-GER1, revealed almost 100% identity with other B. besnoiti isolates obtained in Portugal, Spain, Israel or South Africa, when partial sequences of the 18S ribosomal RNA gene, of the internal transcribed spacer 1 and of the 5.8S RNA gene were compared. Cystozoites obtained from skin tissue of one bull were infectious for γ-interferon knockout (GKO) mice by intraperitoneal (ip) inoculation. Tachyzoites were detected in the peritoneal cavity, spleen, liver and lung of the mice 5 days post-infection. The parasite could be maintained in GKO mice by ip inoculation for at least 5 passages. Peritoneal washings containing tachyzoites were obtained from infected mice and used to infect five cell lines (Vero, MARC-145, NA42/13, BHK₂₁, KH-R). The best growth of tachyzoites was observed in BHK₂₁ cells, but replication occurred to a smaller extent also in MARC-145, NA42/13 and KH-R cells. Subsequent comparative analyses revealed that after direct infection of these cell lines with cystozoites derived from bovine skin, the growth was best in NA42/13 cells. Considerable replication was also observed in the BHK₂₁ and KH-R cell lines. Our observations on the growth characteristics of Bb-GER1 partially contrast those for other isolates. The preferential growth in particular cell lines may be characteristic for particular B. besnoiti isolates. A potential association between growth properties and differences in virulence remains to be established. This is the first in vitro isolation of B. besnoiti from cattle in Germany.     

Anaplasma marginale infection in a Japanese Black cow 13 years after eradication of Rhipicephalus (Boophilus) microplus in Okinawa, Japan

In October 2007, a 15-year-old Japanese Black cow on Ishigaki Island, Okinawa, Japan, was diagnosed with Anaplasma marginale infection based on clinical symptoms, blood examination, smear observation, 16S rRNA and groEL gene sequence analysis, and the result of a CF test. The cow was introduced into the farm from mainland Japan as a calf in 1993, one year before the eradication of Rhipicephalus (Boophilus) microplus, the main vector of A. marginale in Okinawa Prefecture. It is possible that the cow was first infected with A. marginale as a calf in Ishigaki Island and had been persistently infected since then. This is the first reported clinical case of A. marginale infection of cattle since the eradication of R. microplus in Okinawa Prefecture. Additional analysis of major surface protein 1α amino acid sequences revealed that the A. marginale Okinawa strain presented four new repeat forms which were not seen in other strains. This indicates that the Okinawa strain may be a unique geographical variant of A. marginale.     

The bovine annexin 9 gene (ANXA9) is significantly associated with milk-fat yield in a Spanish Holstein–Friesian population

On the basis of QTL studies for milk-fat yield trait on BTA3, annexin 9 protein (ANXA9), fatty acid transport protein type 3 (SLC27A3) and diacylglycerol O-acyltransferase 1 (DGAT1) were selected as candidate genes. Three different single nucleotide polymorphisms (SNPs) of bovine ANXA9, SLC27A3 and DGAT1 genes have been tested in a selective genotyping design for milk-fat yield. Significant allele frequency differences were found for ANXA9 (p = 0.02), in Holstein–Friesian animals with high and low breeding values for milk-fat yield. Regression analysis also showed a significant effect (p = 0.0207) between estimated breeding values (EBVs) for fat milk content and ANXA9 polymorphism. So ANXA9 gene falls into a significant quantitative trait loci interval for milk-fat yield that was previously reported on bovine chromosome 3 in other dairy populations. Our results suggest that the ANXA9 gene polymorphism or a linked segregating QTL contributes to variation in milk-fat yield.     

A recombinant chimera composed of repeat region RR1 of Mycoplasma hyopneumoniae adhesin with Pseudomonas exotoxin: in vivo evaluation of specific IgG response in mice and pigs

Using the binding and translocation domain of Pseudomonas exotoxin A [domain III deleted PE termed PE(ΔIII)] as a vehicle, this study characterized and evaluated a novel application of PE toxin in Mycoplasma hyopneumoniae adhesin used as an immunogen. PCR and sequence analysis revealed that 16 copies of AAKPV(E) in tandem repeat region 1 (RR1) of M. hyopneumoniae 97 kDa adhesion were successfully fused to the downstream of PE(ΔIII) to create a subunit vaccine, i.e. PE(ΔIII)-RR1. This chimeric protein, over-expressed in inclusion bodies of E. coli BL21(DE3)pLysS, was characterized by a monoclonal antibody (MAb) F2G5 prepared against RR1 of the 97 kDa adhesin and was readily purified. The data indicated that the epitope recognized by MAb F2G5 was located in the structure of PE(ΔIII)-RR1. Using ELISA and Western blot analyses, the specific IgG immune response against RR1 and whole adhesin in mice immunized with PE(ΔIII)-RR1 was found more marked than that in mice immunized with the M. hyopneumoniae whole cells. Similarly, PE(ΔIII)-RR1 also stimulated a remarkable IgG response against RR1 in pigs compared to that in pigs immunized with the conventional M. hyopneumoniae vaccine. The PE(ΔIII)-RR1 would be potentially useful for the future development of a M. hyopneumoniae adhesin vaccine.     

Prevalence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Mossoró, Rio Grande do Norte, Brazil

Toxoplasma gondii is an obligate intracellular parasite with a variety of hosts, responsible for reproductive problems and economic losses in sheep flocks. Neospora caninum was recently identified and its clinical presentation in sheep is similar to that of toxoplasmosis, which can cause repeated abortions, though less frequently in this species. In order to confirm the prevalence of these agents in the city of Mossoró, Rio Grande do Norte, Brazil, 409 serum samples from adult sheep (364 females and 45 males) were tested by the indirect immunofluorescence antibody test, using cut-off point at a dilution of 1:64 and 1:50 for T. gondii and N. caninum, respectively. From the 35 properties examined, 23 (65.7%) had at least one seropositive animal for T. gondii and six (17.1%) for N. caninum. The prevalence of seropositive animals for T. gondii was 20.7% and for N. caninum 1.8%. There was no association between the presence of the agent’s antibody and gender, reports of reproductive problems and presence of dogs and/or cats in the properties. T. gondii is well distributed and N. caninum has low prevalence in sheep and in the properties of the studied region.     

In vitro antagonistic activities of Lactobacillus spp. against Brachyspira hyodysenteriae and Brachyspira pilosicoli

The sensitivity of Brachyspira hyodysenteriae and Brachyspira pilosicoli, respectively the causative agents of Swine Dysentery and Porcine Intestinal Spirochaetosis to two probiotic Lactobacillus strains, L. rhamnosus CNCM-I-3698 and L. farciminis CNCM-I-3699 was studied through viability, motility and coaggregation assays. The cell-free supernatant of these lactobacilli contains lactic acid, that is stressful for Brachyspira (leading to the formation of spherical bodies), and lethal. It was demonstrated for the first time the in vitro coaggregation properties of two probiotic Lactobacillus strains (active or heat-treated) with two pathogenic strains of Brachyspira, leading to (1) trapping of spirochaetal cells in a physical network as demonstrated by SEM; (2) inhibition of the motility of Brachyspira. Such in vitro studies should encourage in vivo studies in animal model to evaluate the potential of the use of probiotic lactobacilli through a feeding strategy for the prevention of B. hyodysenteriae and B. pilosicoli.     

Bartonellae in animals and vectors in New Caledonia

Bartonellae are gram-negative facultative intracellular alpha-proteobacteria from the family Bartonellaceae. The natural history of bartonellae consists of a reservoir/host, which is a vertebrate with chronic intravascular infection with sustained bacteremia, and a vector (usually an arthropod) that transfers the bacteria from the reservoir to a susceptible yet uninfected host. In order to reveal the sources and reservoirs of Bartonella infection in animals and vectors in New Caledonia, we collected the blood samples of 64 dogs, 8 cats, 30 bovines, 25 horses and 29 wild deer Cervus timorensis russa and 308 associated blood-sucking parasites (14 keds Hippobosca equina, 258 ticks (22 Rhipicephalus microplus, 235 Rhipicephalus sanguineus, and 1 Haemaphysalis longicornis), 12 fleas Ctenocephalides felis and 24 dog lice Trichodectes canis). We isolated ten strains of Bartonella: four Bartonella henselae from cats and six Bartonella chomelii from cattle. The strains were characterized by sequencing of five genes (16S, ITS, rpoB, gltA and ftsZ). The six strains isolated from cattle were close to the reference strain of B. chomelii and were, probably, imported from France with cattle of Limousin race. PCR showed that 35% of keds collected from deer and 31% of deer were infected by B. aff. schoenbuchensis; all other samples were negative. Our data confirmed that in New Caledonia, as in other regions of the world, cats are the major reservoirs of B. henselae. We also confirmed that Hippoboscidae flies may serve as the vectors of ruminant-associated bartonellae.     

Detection of Bartonella spp. in wild rodents in Israel using HRM real-time PCR

The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S–23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of the three different loci. Bartonella DNA was detected in spleen samples of 19 out of 79 (24%) black rats (R. rattus) and in 1 of 4 (25%) Cairo spiny mice (A. cahirinus). In addition, 15 of 34 (44%) flea pools harbored Bartonella DNA. Only rat flea (Xenopsyla cheopis) pools collected from black rats (R. rattus) were positive for Bartonella DNA. The Bartonella sp. detected in spleen samples from black rats (R. rattus) was closely related to both B. tribocorum and B. elizabethae. The species detected in the Cairo spiny mouse (A. cahirinus) spleen sample was closely related to the zoonotic pathogen, B. elizabethae. These results indicate that Bartonella species are highly prevalent in suburban rodent populations and their ectoparasites in Israel. Further investigation of the prevalence and zoonotic potential of the Bartonella species detected in the black rats and the Cairo spiny mouse is warranted.     

Protection against Toxoplasma gondii brain cyst formation in mice immunized with Toxoplasma gondii cytoskeleton proteins and Lactobacillus casei as adjuvant

The aim of the study was to evaluate the protection generated in mice against Toxoplasma gondii brain cyst burden by vaccination with T. gondii cytoskeleton proteins using Lactobacillus casei as adjuvant. One hundred and sixty-eight NIH mice were randomly allocated into eight groups of 21 mice each. Animals were immunized as follows: in group 1 with Toxoplasma lysate antigen (TLA) in Freund's modified adjuvant, containing L. casei (FMA), in group 2 with Toxoplasma cytoskeleton proteins (TCPs) in FMA, in group 3 with FMA, in group 4 with phosphate buffered saline (PBS), in group 5 with L. casei dead by heath (Lc), in group 6 with Freund's complete adjuvant (FCA), in group 7 with TLA in FCA, and in group 8 with TCP in FCA. Mean brain cyst burden (±S.E.M.) was assessed in mice 8 weeks after challenge with T. gondii Me49 strain (20 cysts per mouse). The percentages of reduction in cyst burden per brain (P < 0.01) as compared with the group 4 (control: mean 3181 ± 97.5) were 77.25% (724 ± 98) in group 1, 88.02% (381 ± 97.5) in group 2, 38.92% (1943 ± 130.3) in group 3, 44.31% (1771.4 ± 102) in group 5, 59.28% (1295.2 ± 99.1) in group 7 and 55.69% (1409.5 ± 89.9) in group 8. In order of importance, the best protection was obtained in groups 2, 1, 7, 8, 5 and 3. Noticeably the mice inoculated with L. casei alone showed a significant reduction in T. gondii brain cysts (P < 0.01), while those animals treated with FCA alone did not. Additionally, IgM anti-T. gondii antibody levels, as determined by ELISA 2 weeks after challenge, were highest in group 2 (P < 0.01) than in the other seven groups. Results suggest that T. gondii cytoskeleton proteins with L. casei as adjuvant constitute a good anti-toxoplasmosis vaccine candidate.     

猪囊尾蚴西昌分离株线粒体cox1和nad1基因的序列测定与种系发育分析

应用PCR技术对3个猪囊尾蚴西昌分离株的线粒体细胞色素C氧化酶第Ⅰ亚基(cox1)基因全序列和烟酰胺腺嘌呤二核苷酸还原酶第一亚基(nad1)基因部分序列进行扩增,分析其遗传变异,并用Mega 5.0程序NJ法绘制种系发育树,探讨不同地区来源的猪囊尾蚴种系发育关系。测序结果显示,猪囊尾蚴的cox1基因全序列长度为1 620bp,nad1基因部分序列长度为796bp。cox1和nad1基因序列均存在一定的遗传变异,且cox1基因序列的变异高于nad1序列。种系发育分析结果显示,所有猪囊尾蚴分离株构成一个分支,3个西昌分离株均属于猪带绦虫亚洲基因型。结果表明,cox1和nad1基因均可用于猪带绦虫的分子分类,为猪带绦虫病/猪囊尾蚴病的分子诊断奠定了基础。     

Identification of Rickettsia felis in fleas but not ticks on stray cats and dogs and the evidence of Rickettsia rhipicephali only in adult stage of Rhipicephalus sanguineus and Rhipicephalus haemaphysaloides

Rickettsia spp. are zoonotic pathogens and mainly transmitted by various arthropod vectors, such as fleas, ticks, and lice. Previous epidemiological studies indicated that ectoparasites infested on dogs or cats may be infected by Rickettsia spp., and transmit them to human beings accidentally. In this study, the prevalence of Rickettsia infection was evaluated using fleas and ticks from stray dogs and cats in Taiwan. A total of 158 pools made by 451 cat fleas (Ctenocephalides felis) from 37 dogs and 4 cats were used for analysis. Besides, 386 Rhipicephalus ticks collected from the other 62 stray dogs were included in this study. Nymphal and adult ticks were individually analyzed but larvae were separated into 21 pools for molecular detection. Partial sequencing analysis of the gltA gene was applied for Rickettsia identification. The results showed that 44.3% (70/158) of the cat flea pools were harboring Rickettsia DNA. Although 6.9% (13/187) of adult ticks were infected with Rickettsia, neither larval pools nor nymphal ticks were found to contain Rickettsia DNA. According to the results of sequencing analyses, all Rickettsia PCR-positive cat flea pools were infected with R. felis, and all Rickettsia PCR-positive adult ticks were infected with R. rhipicephali. The results of this study demonstrated that C. felis but not Rhipicephlus sanguineus (the brown dog tick) and Rh. haemaphysaloides collected from stray animals in Taiwan could be infected the zoonotic pathogen R. felis. Moreover, R. rhipicephali was only identified in adult stage of Rhipicephalus sanguineus and Rh. haemaphysaloides.     

Gastric Helicobacter species as a cause of feline gastric lymphoma: A viable hypothesis

Gastric Helicobacter spp. are associated with chronic inflammation and neoplastic transformation in humans as well as domestic and laboratory species. The present study examined the association of Helicobacter heilmannii (Hhe) infection in pet cats with feline gastric mucosa associated lymphoid tissue (MALT) lymphoma. Tissues were collected via gastric biopsy or at necropsy from 47 pet cats with clinical signs of gastrointestinal disease, including vomiting and inappetance, and classified as gastritis (14/47), lymphoma (31/37), or normal (2/47). Tissues positive for argyrophilic organisms with Warthin–Starry stain (29/47) were assessed by fluorescent in situ hybridization (FISH) for the presence of Hhe strains 1–4 as well as with a fifth probe that detected Helicobacter salomonis, Helicobacter bizzozeronii, or Helicobacter felis. A significant association of positive Warthin–Starry status with Hhe infection was found in cases of sick cats (22/29; p < 0.05 by Chi-square; χ² = 7.034). Interestingly, a significant association between Hhe status and a diagnosis of lymphoblastic or lymphocytic lymphoma was observed as well in a subset of 24 Warthin–Starry positive lymphoma cases: of lymphoblastic lymphoma cases, 13/17 were positive for Hhe (p < 0.05; χ² = 4.854). Hhe strains 2 and 4 were most commonly found (18/29 and 17/29, respectively) among sick cats, although a higher than expected number of cats was also positive for Hhe1, which initial reports have described as rare in cats and common in humans. The association found between a positive Hhe status with the presence of feline gastric lymphoma, especially lymphoblastic lymphoma, argues for the need to conduct prospective studies to better identify the frequency and strain distribution of Hhe infection in both healthy and clinically ill cats, particularly those cats with gastric lymphoma.     

Deletion of sodCI and spvBC in Salmonella enterica serovar Enteritidis reduced its virulence to the natural virulence of serovars Agona, Hadar and Infantis for mice but not for chickens early after infection

Salmonella enterica serovars Typhimurium, Enteritidis, Dublin, Choleraesuis or Gallinarum can colonise liver and spleen in particular hosts while infections with serovars Infantis, Agona, Hadar, etc. are usually limited to gastrointestinal tract. Reasons for this behavior are unknown, although it has been shown that sodCI and spv genes exhibit a strict distribution between more and less virulent serovars and they influence Salmonella virulence. However to what extent the presence or absence of these genes is associated with the increased virulence of serovars which possess them has never been addressed experimentally. In this study we therefore first confirmed the exclusive association of spvB and sodCI genes with the former group of serovars. In the next step we removed these two genes from S. Enteritidis genome and compared the virulence of such a mutant with the virulence of S. Infantis, S. Agona and S. Hadar for chickens and highly sensitive Balb/C mice. Single strain infection showed that the deletion of these two genes from S. Enteritidis resulted in the reduction of its virulence for mice but not for chickens. Mixed infection further confirmed these observations and indicated that in mice but not in chickens the virulence of sodCI and spv mutant was reduced to the natural virulence of serovars Infantis, Agona and Hadar. Although sodCI and spv genes do not influence S. Enteritidis virulence for chickens directly, they may be of an indirect effect through the increased persistence of S. Enteritidis in mice and increased probability of the reintroduction of S. Enteritidis into poultry flocks.     

Standardization of the outbred BALB/c mice as a suitable animal model for <Emphasis Type="BoldItalic">Besnoitia caprae</Emphasis> studies

The Apicomplexan parasite Besnoitia caprae infects wild and domestic goats. Knowledge on Besnoitia caprae specially an optimized animal model is sparse. Experimental infections with tachyzoites of BC-Pars obtained from BALB/c mice were conducted in outbred mice to determine the infectivity and LD50 of Besnoitia caprae. Six groups of five mice were intraperitoneally infected with 12.5 × 10³, 25 × 10³, 5 × 10⁴, 1 × 10⁵ and 2 × 10⁵ tachyzoites and a control inoculum of DMEM, respectively. Although morbidity and mortality were observed in all groups, two mice in the 12.5 × 10³ group showed alopecia and skin lesions on 60 days post-infection (DPI). Histopathological and molecular examination of skins confirmed B. caprae infection. The LD₅₀ was calculated as 25 × 10^3.2 tachyzoites per mouse. The results indicate that outbred BALB/c mice can be used as a suitable model of besnoitiosis and to screen candidate treatments and to test the efficacy of vaccines for besnoitiosis.     

Phylogentic analysis of Anaplasma ovis strains isolated from sheep and goats using groEL and mps4 genes

Evidence of Anaplasma spp. in goats and sheep in Cyprus has been demonstrated by previous research. Herein, further research was performed for the identification of the exact Anaplasma spp. resulting in the identification of Anaplasma ovis strains in all samples examined. We used a bioinformatics as well as a molecular approach (study of groEl and mps4 genes) in order to verify the validity of the results. All samples depicted the presence of A. ovis regardless of the host (goat or sheep).     

Bacteria of Pathogenic Importance in Faeces from Cadavers of Free-ranging or Corralled Semi-domesticated Reindeer in Northern Norway

There is little information on bacteria that have the potential to cause disease in reindeer husbandry. In this project, faecal samples from 35 free-ranging or corralled reindeer, adults and calves, that died in the winter of 2000 in northern Norway, were examined for the occurrence of Campylobacter spp., Clostridium perfringens, Listeria spp., Salmonella spp. and Yersinia spp. to evaluate the role of these microrganisms in loss and mortality in reindeer husbandry. In addition, 31 of these samples were examined for the occurrence of bacteria producing shigatoxin-1 and 2. C. perfringens was isolated in 20 (57.1%) of the faecal samples. In the free-ranging reindeer, 44% were positive carriers of C. perfringens and 90% of the corralled ones were positive for C. perfringens. In addition, the gene encoding for shigatoxin-1 was detected in one of the samples derived from a corralled reindeer. The other bacteria investigated were not found. Shigatoxin-1-producing bacteria were isolated for the first time from reindeer in Norway. However, no correlation between C. perfringens or shigatoxin-1-producing bacteria and mortality in the reindeer could be established.     

PCR-based detection of blood parasites in cattle and adult Rhipicephalus appendiculatus ticks

To ascertain the infection rate for tick-borne pathogens in Zambia, an epidemiological survey of Theileria parva, Babesia bigemina and Anaplasma marginale in traditionally managed Sanga cattle was conducted using PCR. Of the 71 native Zambian cattle, 28 (39.4%) were positive for T. parva, 16 (22.5%) for B. bigemina and 34 (47.9%) for A. marginale. The mixed infection rate in cattle was 8.5% (6/71), 16.9% (12/71), 7.0% (5/71) and 2.8% (2/71) for T. parva/B. bigemina, T. parva/A. marginale, B. bigemina/A. marginale and T. parva/B. bigemina/A. marginale, respectively.To predict the risk for transmission of tick-borne pathogens from ticks to cattle, a total of 74 Rhipicephalus appendiculatus ticks were collected from a location where cattle had been found positive for T. parva. Of the ticks collected, 10 (13.5%) were found to be PCR-positive for T. parva. The results suggest that the infection rate for tick-borne pathogens was relatively high in Sanga cattle and that adult R. appendiculatus ticks were highly infected with T. parva.     

Host Switch of <Emphasis Type="Italic">Lamellodiscus elegans</Emphasis> (Monogenea: Monopisthocotylea) and <Emphasis Type="Italic">Sparicotyle chrysophrii</Emphasis> (Monogenea: Polyopisthocotylea) between Cage-reared Sparids

Sharpsnout bream (Diplodus puntazzo) has been used in Adriatic aquaculture for less than a decade, but the decreasing trend of rearing this species will probably result in its complete substitution by more exploited sea bream (Sparus aurata). Only two facilities still rear both fish species in neighbouring cages in monoculture. A switch of parasites was observed between sparids during monitoring of the gill monogeneans of farmed fish. In wild fish of the Adriatic Sea, Lamellodiscus elegans (Monogenea: Monopisthocotylea) has previously been reported in annular (Diplodus annularis), and two-banded sea bream (D. vulgaris) and sharpsnout bream (D. puntazzo), and the present study confirmed its presence also in sea bream, in low prevalence and abundance. The exclusively sea bream monogenean Sparicotyle chrysophrii (Monogenea: Polyopisthocotylea) was also isolated from sharpsnout bream, showing prevalence and abundance values even higher than in its resident host. In the occurrence of L. elegans in sea bream, the opportunistic switch resulted in lower abundance and prevalence than in the original host, while in the second case of switching the monogenean S. chrysophrii showed better reproductive capacity on a new host (sharpsnout bream). Both cases point to the possible enlargement of parasite host range.     

羊口疮病毒贵州株F1L基因克隆及生物信息学分析

为分析羊口疮病毒贵州株(ORFV-GZ株)F1L基因的分子特点,预测编码蛋白的生物学功能,本试验对ORFV-GZ株F1L基因进行PCR扩增、克隆及序列测定。应用生物信息学相关软件及方法,对ORFV-GZ株F1L基因进行列分析并对其编码蛋白进行了二级结构、B细胞表位、保守结构域、跨膜结构域和信号肽预测。结果显示,F1L基因PCR扩增产物大小为1 029bp,编码342个氨基酸;与OV-SA00株、NZ2株、OV-IA82株和D1701株相应序列核苷酸同源性分别为98.4%、97.9%、97.8%和96.8%,氨基酸的同源性分别为98.3%、97.6%、97.3%和95.3%;系统进化树显示,ORFV-GZ株F1L基因与FJ-GT株亲缘关系最近;二级结构以α-螺旋和无规则卷曲所占比例较大,预测此蛋白可能存在7个B细胞优势抗原表位,两个跨膜区域,无信号肽区域。本试验结果将为贵州省ORFV免疫诊断及核酸疫苗研究提供理论依据。