Veterinary parasitology最新文献_第5页

From nucleation to capping: The lifecycle of an actin filament in Toxoplasma gondii gliding 从成核到封盖：刚地弓形虫滑翔中肌动蛋白丝的生命周期

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-12-23 DOI: 10.1016/j.vetpar.2025.110679

Muhammad Farhab , Yu-Guo Yuan

Toxoplasma gondii is an obligate intracellular apicomplexan parasite whose motility, host cell invasion, and egress are powered by a unique actomyosin system. Unlike canonical actins that form stable filaments, T. gondii actin (TgACT1) is highly dynamic, existing predominantly in a monomeric state. This review traces the lifecycle of TgACT1, from nucleation to capping, to elucidate how the parasite harnesses rapid cytoskeletal turnover for gliding motility. This review discusses how TgACT1’s intrinsic properties—including isodesmic polymerization, rapid subunit turnover, and specific amino acid substitutions that confer instability—are complemented by a minimal set of TgACT1-binding proteins (e.g., formins, TgPRF, toxofilin, ADF) to maintain a readily available pool of polymerization-competent monomers. The force for motility is generated by the glideosome, a specialized motor complex where myosin A walks along short, dynamic filaments, translocating adhesins rearward to propel the parasite. Finally, the therapeutic potential of targeting this essential and divergent system is discussed, highlighting the druggability of TgACT1 and the immunogenic properties of key regulators. Understanding the molecular mechanisms of TgACT1 dynamics reveals vulnerabilities that could be exploited for novel anti-parasitic strategies.

刚地弓形虫是一种专性细胞内顶复合体寄生虫，它的运动、宿主细胞的入侵和出口都是由一种独特的肌动球蛋白系统提供动力的。与形成稳定细丝的典型肌动蛋白不同，弓形虫肌动蛋白（TgACT1）是高度动态的，主要以单体状态存在。这篇综述追溯了TgACT1的生命周期，从成核到盖帽，以阐明寄生虫如何利用快速的细胞骨架更新来进行滑翔运动。这篇综述讨论了TgACT1的固有特性——包括等聚、快速亚基转换和赋予不稳定性的特定氨基酸取代——是如何通过一组最小的TgACT1结合蛋白（如formmins、TgPRF、toxofilin、ADF）来补充的，以维持一个容易获得的聚合能力单体库。这种动力是由滑体产生的，滑体是一种特殊的运动复合体，肌球蛋白a沿着短而动态的细丝行走，将黏附素向后转移以推动寄生虫。最后，本文讨论了靶向这一重要和分化系统的治疗潜力，重点介绍了TgACT1的可药物性和关键调节因子的免疫原性。了解TgACT1动力学的分子机制揭示了可以利用新的抗寄生虫策略的漏洞。

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引用次数: 0

Assessing the efficacy of three trypanocidal drugs in controlling Trypanosoma evansi 三种杀锥虫药物防治伊氏锥虫的疗效评价。

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-11-29 DOI: 10.1016/j.vetpar.2025.110658

Somaia Abouakkada , Nadia Labn , Safeya Henidy , Samah S. Oda , Mohamed E. Abd El-Hack , Fatima S. Alaryani , Aishah E. Albalawi , Kamlah Ali Majrashi , Amira Dewair

Trypanosoma evansi is an emerging zoonotic threat causing significant economic and health issues, especially in tropical and subtropical regions. Due to limited effective trypanocidal agents and increasing drug resistance, this investigation sought to evaluate the therapeutic efficacy of quinapyramine sulfate and chloride, melarsamine hydrochloride, and diminazene aceturate in 72 female Swiss albino mice. Each drug was administered at two dosages: quinapyramine (3 and 6 mg/kg), melarsamine hydrochloride (0.25 and 0.5 mg/kg), and diminazene aceturate (3.5 and 7 mg/kg). The efficacy was evaluated based on parasitaemia, relapse patterns, body weight changes, hematological and biochemical profiles, postmortem and histopathological findings. The results showed quinapyramine was ineffective at both dosages. However, doubling the therapeutic doses of melarsamine hydrochloride and diminazene aceturate enhanced their efficacy, although parasitaemia relapsed in all cases. Blood biochemical analyses revealed infection-induced anemia, leukocytosis, eosinophilia, and significant reductions in total protein, serum albumin, and globulin levels. Histopathological examination revealed evidence of degenerative pathology and tissue injury within the hepatic, splenic, cardiac, and renal parenchyma in all experimental groups with varying degrees. These findings suggest that melarsamine hydrochloride, at higher doses, may offer a more effective treatment for T. evansi infection, although relapse remains a challenge.

伊文氏锥虫是一种新兴的人畜共患威胁，造成重大的经济和健康问题，特别是在热带和亚热带地区。由于有效的锥虫杀灭剂有限且耐药性增加，本研究试图评估硫酸喹帕胺和氯化物、盐酸三聚氰胺和醋酸咪纳苯对72只雌性瑞士白化病小鼠的治疗效果。每种药物以两种剂量给药：quinapyramine（3和6 mg/kg）、盐酸三聚氰胺（0.25和0.5 mg/kg）和醋酸咪纳苯（3.5和7 mg/kg）。根据寄生虫血症、复发模式、体重变化、血液学和生化特征、死后和组织病理学结果评估疗效。结果表明，两种剂量的喹奈吡明都无效。然而，加倍治疗剂量的盐酸三聚氰胺和醋酸地咪那烯增强了它们的疗效，尽管寄生虫病在所有病例中复发。血液生化分析显示感染引起的贫血、白细胞增多、嗜酸性粒细胞增多，总蛋白、血清白蛋白和球蛋白水平显著降低。组织病理学检查显示，各实验组均有不同程度的肝、脾、心、肾实质变性病理及组织损伤。这些发现表明，高剂量的盐酸三聚氰胺可能对伊文氏弓形虫感染提供更有效的治疗，尽管复发仍然是一个挑战。

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引用次数: 0

Is it ovine cystic echinococcosis? Post-mortem inspection compared to laboratory analyses of lesions from a slaughterhouse in a hypo-endemic area of northern Italy 是羊囊性包虫病吗？将死后检查与意大利北部低流行区屠宰场病变的实验室分析进行比较

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-12-02 DOI: 10.1016/j.vetpar.2025.110671

M. Rega , M. Fozzer , M. Genchi , C. Cattabiani , M. Semeraro , M. Conter , M. Di Pentima , F. Armando , G. Muresu Ibba , L. Kramer , A. Vismarra

The larval stage of Echinococcus granulosus sensu lato causes cystic echinococcosis (CE), an important parasitic zoonotic disease infecting over an estimated one million people worldwide. Canids act as definitive hosts while livestock, mainly sheep, serve as intermediate hosts for the larval stage. Inspection at slaughter of intermediate hosts and destruction of affected organs play an important role in limiting parasite spread. The aim of the present study was to evaluate, over a 6-month period, the prevalence of CE in sheep in an hypo-endemic area for E. granulosus, as determined at slaughter and to verify diagnosis in the laboratory through gross morphological evaluation, histopathology and a multiplex end-point PCR. Sample collection was performed in an ovine slaughterhouse in northern Italy. Lungs and livers were examined visually and those with lesions compatible with CE according to the official veterinary control were then conferred to the laboratory. A total of 421 sheep were examined and CE was suspected in 101/421 (24 %). Following incision, however, only 36/101 showed lesions with morphological features of CE. Histology and end-point PCR were positive for E. granulosus in only 25/36 sheep, highlighting the CE prevalence at 5.9 % (25/421). Results suggest that current inspection at slaughter based on visualization alone may over-estimate CE prevalence in particular in hypo-endemic areas.

囊性棘球蚴病是一种重要的寄生虫性人畜共患疾病，据估计全世界有超过100万人感染。犬科动物作为最终宿主，而家畜，主要是羊，作为幼虫阶段的中间宿主。屠宰中间宿主时的检查和受感染器官的破坏在限制寄生虫传播方面起着重要作用。本研究的目的是评估在屠宰时确定的颗粒棘球绦虫低流行区绵羊中CE的流行情况，并通过大体形态学评估、组织病理学和多重终点PCR验证实验室诊断。样本采集在意大利北部的一个绵羊屠宰场进行。肉眼检查肺和肝脏，然后根据官方兽医控制将符合CE的病变交给实验室。共检查421只羊，101/421（24% %）疑似CE。而切开后，只有36/101出现CE形态特征的病变。组织学和终点PCR仅在25/36的绵羊中呈颗粒棘球蚴阳性，表明CE患病率为5.9 %（25/421）。结果表明，目前仅基于可视化的屠宰检查可能高估了CE的流行率，特别是在低流行地区。

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引用次数: 0

Intestinal parasites in dogs and their association with clinical manifestations of canine visceral leishmaniasis 犬肠道寄生虫及其与犬内脏利什曼病临床表现的关系

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-11-28 DOI: 10.1016/j.vetpar.2025.110659

Allan de Jesus Mendonça Severino , Dharliton Soares Gomes , André Tetzl Costa , Maykelin Fuentes Zaldívar , Nathália Moreira Teodoro de Oliveira , Bianca Leal de Oliveira , Paulo Ricardo Silva Coelho , Felipe Bisaggio Pereira , Paulo Ricardo de Oliveira Paes , João Carlos França-Silva , Rodolfo Cordeiro Giunchetti , Stefan Michael Geiger

Dogs are companion animals commonly present in spaces shared with humans. However, this close contact may facilitate the transmission of zoonoses, such as canine visceral leishmaniasis (CVL). Additionally, dogs are potential hosts of endoparasites that can influence the clinical manifestations of CVL due to immunological interference occurring in parasitic coinfections. This study aimed to investigate the occurrence of endoparasites in domestic dogs seropositive for CVL and associate their clinical manifestations with the presence of intestinal helminths. We analyzed 47 seropositive dogs (51.06 % males; 48.9 % females; 80.8 % of undefined breed) that underwent clinical examination, blood count, euthanasia, necropsy, and coproparasitological diagnosis. Dogs were grouped into three clinical categories: low (40.4 %), medium (34.0 %), and severe (25.5 %) based on a modified version of the LeishVet clinical staging system. Coproparasitological results indicated Ancylostoma sp. and Giardia sp. as the most prevalent. Based on necropsy, Ancylostoma sp. and Dipylidium caninum were the most common helminths. Dogs with CVL and intestinal helminths frequently had macrocytic hypochromic (p = 0.0455) and microcytic hypochromic (p = 0.01963) anemia. We also found that Ancylostoma sp. was associated with more severe CVL clinical staging (odds ratio [OR] = 3.3621; 95 % confidence interval [CI] = 2.6413–4.2796) and negatively associated with red blood cell counts (OR = 0.9278; CI = 0.8702–0.9893). We conclude that intestinal helminth infections in dogs with CVL may represent an important aggravating factor for the disease’s clinical progression.

狗是陪伴动物，通常出现在与人类共享的空间。然而，这种密切接触可能促进人畜共患病的传播，如犬内脏利什曼病（CVL）。此外，由于寄生虫共感染中发生的免疫干扰，狗是内寄生虫的潜在宿主，可影响CVL的临床表现。本研究旨在了解CVL血清阳性家养犬体内寄生虫的发生情况，并将其临床表现与肠道蠕虫的存在联系起来。我们分析了47只血清阳性犬（51.06 %雄性；48.9 %雌性；80.8 %未定义品种），进行了临床检查、血球计数、安乐死、尸检和共寄生虫学诊断。根据改进版的LeishVet临床分期系统，将犬分为三个临床类别：低（40.4 %）、中（34.0 %）和严重（25.5 %）。伴寄生虫学结果显示以钩虫和贾第鞭毛虫为主。尸检结果显示，最常见的是钩虫和犬双螺旋虫。感染CVL和肠蠕虫的狗常发生大细胞性低色素血症（p = 0.0455）和小细胞性低色素血症（p = 0.01963）。我们还发现钩虫与更严重的CVL临床分期相关（比值比[OR] = 3.3621； 95 %置信区间[CI] = 2.6413-4.2796），与红细胞计数负相关（OR = 0.9278; CI = 0.8702-0.9893）。我们的结论是，肠道蠕虫感染的狗与CVL可能代表一个重要的加重因素，疾病的临床进展。

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引用次数: 0

Application of in vitro insecticide selection pressure to a susceptible strain of the sheep blowfly reveals different rates of resistance development and cross-resistance patterns 应用体外杀虫剂选择压力对一株羊蝇敏感品系进行筛选，发现不同的抗性发展速率和交叉抗性模式

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-11-28 DOI: 10.1016/j.vetpar.2025.110661

Andrew C. Kotze , Neil H. Bagnall , Angela P. Ruffell , Nicholas M. Rolls

The present study aimed to investigate the development of resistance to the pyrimidine derivative dicyclanil and the neonicotinoid imidacloprid in the sheep blowfly, Lucilia cuprina. We applied laboratory-based insecticide selection pressure to a susceptible strain and measured resistance patterns that emerged to all of the currently-available blowfly control chemicals. The dynamics of resistance emergence was quite different for the two compounds. Resistance to imidacloprid emerged after 4 rounds of selection, increased up to 9 rounds before then remaining relatively constant at almost 10-fold until the termination of the experiment after 15 rounds. Dicyclanil resistance did not emerge until the 13th round of selection, and then increased to approximately 3.5-fold at 15 rounds. This faster development of resistance to imidacloprid is in agreement with observations of resistance emergence in field populations of the blowfly over the last 25 years. The imidacloprid-selected strain also developed resistance towards dicyclanil (3.1-fold). Similarly, the dicyclanil-selected strain also showed resistance to imidacloprid (4.8-fold). This level of resistance to imidacloprid in the dicyclanil-selected strain (4.8-fold) was slightly higher than the level of resistance to dicyclanil itself (3.5-fold). The study provides insights into the dynamics of resistance emergence to different compounds in the sheep blowfly and describes cross-resistance patterns with important implications for chemical rotation strategies. In demonstrating the emergence of resistance to two chemical classes after exposure to single classes, this study illustrates the need to examine the potential impact of resistance mechanisms that can act across multiple insecticide classes when designing insecticide-use strategies for parasite control.

本研究旨在研究羊绿蝇对嘧啶衍生物双环苯胺和新烟碱类吡虫啉的抗性发展。我们对一个易感菌株施加了基于实验室的杀虫剂选择压力，并测量了对目前所有可用的苍蝇控制化学品的抗性模式。两种化合物的抗性产生动态有很大不同。对吡虫啉的抗性在4轮后出现，增加到9轮，然后保持相对稳定，几乎是10倍，直到15轮后实验终止。直到第13轮筛选才出现双环兰耐药，然后在第15轮时增加到约3.5倍。这种对吡虫啉抗药性的快速发展与过去25年来在田间苍蝇种群中出现抗药性的观察结果相一致。选择吡虫啉的菌株对双环腈也产生了抗性（3.1倍）。同样，选择双环苯胺的菌株对吡虫啉也表现出4.8倍的耐药性。对吡虫啉的耐药水平（4.8倍）略高于对双环氯胺本身的耐药水平（3.5倍）。该研究提供了对绵羊苍蝇对不同化合物产生抗性的动力学见解，并描述了交叉抗性模式，对化学轮换策略具有重要意义。在证明暴露于单一化学类别后出现对两种化学类别的抗性时，本研究表明，在设计用于寄生虫控制的杀虫剂使用策略时，需要检查可跨多种杀虫剂类别的抗性机制的潜在影响。

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引用次数: 0

Double antigen sandwich ELISA for detection of antibodies against Babesia bovis. 双抗原夹心ELISA法检测牛巴贝斯虫抗体。

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-11-21 DOI: 10.1016/j.vetpar.2025.110657

María Evangelina Primo, Beatriz Susana Valentini, Matilde Mazzucco Panizza, Nicolás Morel, Carolina Soledad Thompson

Babesia bovis is a hemoparasite responsible for bovine babesiosis, an economically important tickborne disease widespread in tropical and subtropical regions of the world. Serological tests are used in calves to evaluate the need for vaccination and the immunity achieved after vaccination. We developed, validated, and evaluated under field conditions a double-antigen sandwich ELISA (dasELISA) using a recombinant major surface antigen 2c (MSA2c) from a pathogenic and an attenuated B. bovis strain. The tests were validated using a panel of 1057 serum samples of known status (217 known-positive and 840 known-negative). Samples from 116 herds (n = 2771) were evaluated by indirect ELISA (iELISA) and dasELISA. Samples with disagreement between ELISAs (231 out of 594, 38.9 %) were analyzed by IFAT. The dasELISA cutoff was ≥ 52 %P, with a diagnostic sensitivity of 94.5 % (95 % CI, 90.5–97.1) and a diagnostic specificity of 96.4 % (95 % CI, 94.9–97.6). The area under the curve (AUC) was assessed to be 0.979, which corresponds to an excellent ability of the assay to discriminate truly infected from truly uninfected animals. Concordance among dasELISA and iELISA was 78.6 %, with a κ value of 0.567 (95 % CI = 0.537–0.598); meanwhile, 57 % and 43 % of the IFAT results agreed with dasELISA and iELISA, respectively. The dasELISA could be useful for large-scale detection of anti–B. bovis antibodies in calves pre- and post-vaccination and for seroepidemiologic investigations, given its appropriate sensitivity and specificity and the simplicity of production.

牛巴贝斯虫是一种导致牛巴贝斯虫病的血液寄生虫，牛巴贝斯虫病是一种广泛存在于世界热带和亚热带地区的重要经济蜱传疾病。在犊牛中使用血清学试验来评估接种疫苗的必要性和接种后获得的免疫力。我们开发、验证并在现场条件下评估了双抗原夹心ELISA (dasELISA)，该ELISA使用来自致病性和减毒牛b菌株的重组主表面抗原2c （MSA2c）。使用一组已知状态的1057份血清样本（217份已知阳性，840份已知阴性）对这些检测进行了验证。采用间接ELISA （iELISA）和dasELISA对116头牛（n = 2771）的样品进行评价。elisa检测结果不一致的样品（594个样品中的231个，38.9 %）采用IFAT分析。dasELISA截止值≥ 52 %P，诊断敏感性为94.5 %(95 % CI, 90.5 ~ 97.1)，诊断特异性为96.4 %（95 % CI, 94.9 ~ 97.6）。曲线下面积（AUC）为0.979，表明该方法具有较好的区分真正感染动物和真正未感染动物的能力。dasELISA与iELISA的一致性为78.6% %，κ值为0.567(95 % CI = 0.537 ~ 0.598)；同时，57 %和43 %的IFAT结果分别与dasELISA和iELISA一致。该酶联免疫吸附试验可用于抗b抗体的大规模检测。鉴于其适当的敏感性和特异性以及生产的简单性，在小牛接种前后以及用于血清流行病学调查的牛抗体。

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引用次数: 0

Integrated pharmacokinetic–pharmacodynamic analysis of macrocyclic lactones in sheep infested with resistant Psoroptes ovis 耐药羊角菌感染羊体内大环内酯的药动学-药效学综合分析。

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-12-24 DOI: 10.1016/j.vetpar.2025.110681

Rodolfo Herrera , Victoria Miró , Adrián Lifschitz , Marcela Larroza

The current study aimed to investigate the pharmacokinetic/pharmacodynamic (PK/PD) relationship of five macrocyclic lactone (MLs) formulations, three 1 % formulations (ivermectin, doramectin and moxidectin) and two long-acting 3.15 % products (ivermectin and doramectin), against sheep experimentally infested with resistant Psoroptes ovis under standardized doses. Thirty naïve Merino sheep were experimentally infested and randomly assigned to five treatment groups (n = 6). Baseline mite counts were not used to block animals during group allocation. The three 1 % formulations of ivermectin (IVM), doramectin (DRM), and moxidectin (MXD), were administered off-label at a dose of 0.5–0.6 mg/kg on days 0 and 7, subcutaneously. The long-acting 3.15 % formulations were subcutaneously administered once at their approved doses of 1.05 mg/kg (IVM 3.15 %) and 1.26 mg/kg (DRM 3.15 %). Plasma drug concentrations and mite counts were assessed between 0 and 35 days post-treatment. Conventional 1 % formulations produced higher peak plasma concentrations than long-acting formulations, although the latter showed greater persistence, similar to that observed with repeated MXD 1 %. DRM 1 % showed greater systemic exposure compared to 3.15 % long acting formulations and IVM 1 %. Significant reductions in mite counts were observed by day 7 with DRM 1 %, and by day 14 with IVM 1 % and MXD 1 %. In contrast, long-acting formulations showed delayed responses, with significant reductions only by day 21. Only DRM 1 % and MXD 1 % achieved 100 % efficacy. PK/PD indices established for ML-resistant P. ovis were calculated as the ratio between peak plasma concentration (Cmax) and the minimal inhibitory concentration (MIC) values of 15 and 30 ng/mL (Cmax/MIC), as well as the ratios between the area under the concentration–time curve (AUC) and the same MIC values (AUC/MIC). The Cmax/MIC ratio observed for 1 % formulations were significantly higher compared to those obtained with the long-acting formulations at both MIC levels. For the AUC/MIC parameter, the 1 % formulations exhibited significantly higher values compared to the long-acting formulations for the MIC 30 ng/mL.These findings suggest that both the magnitude and duration of MLs in plasma are critical for efficacy against P. ovis.

本研究旨在研究5种大环内酯制剂、3种1 %制剂（伊维菌素、多拉菌素和莫西菌素）和2种3.15 %长效制剂（伊维菌素和多拉菌素）在标准剂量下对实验性耐药绵羊感染的药代动力学/药效学（PK/PD）关系。试验感染naïve美利奴羊30只，随机分为5个处理组（n = 6）。在分组分配期间，基线螨数不用于阻止动物。伊维菌素（IVM）、多拉菌素（DRM）和莫西菌素（MXD）的三种1 %配方，在第0天和第7天以0.5-0.6 mg/kg的剂量进行标签外皮下给药。长效制剂3.15 %皮下注射一次，批准剂量为1.05 mg/kg （IVM 3.15 %）和1.26 mg/kg （DRM 3.15 %）。在治疗后0 ~ 35天评估血浆药物浓度和螨计数。传统的1 %制剂比长效制剂产生更高的峰值血浆浓度，尽管长效制剂表现出更强的持久性，类似于重复使用MXD 1 %所观察到的。与长效制剂3.15 %和IVM 1 %相比，DRM 1 %显示出更大的系统性暴露。第7天，drm1 %，第14天，ivm1 %和mxd1 %，螨数显著减少。相比之下，长效制剂表现出延迟反应，仅在第21天显著减少。只有drm1 %和mxd1 %的疗效达到100% %。建立耐药葡萄球菌的PK/PD指标，计算为15和30 ng/mL的最大血浆浓度（Cmax）与最小抑制浓度（MIC）之比（Cmax/MIC），以及浓度-时间曲线下面积（AUC）与相同MIC值（AUC/MIC）之比。1 %制剂的Cmax/MIC比显著高于长效制剂在两个MIC水平下的Cmax/MIC。对于AUC/MIC参数，1 %配方的值明显高于长效配方的30 ng/mL。这些发现表明，血浆中MLs的大小和持续时间对抗鹅肝杆菌的疗效至关重要。

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引用次数: 0

Fasciola hepatica vaccine based on Kunitz-type molecule reduces adult worm fecundity in experimentally infected sheep 基于kunitz型分子的肝片形吸虫疫苗可降低实验感染绵羊的成虫繁殖力

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-11-19 DOI: 10.1016/j.vetpar.2025.110654

María Ahumada , Lorena Guasconi , Belkys Angélica Maletto , Constanza Marín , Santiago Daniel Palma , Cesar Iván Pruzzo , Corvo Ileana , Gabriel Caffe , Ana María Martin , Laura Chiapello , Laura Cervi

Fasciolosis is a widespread and continuously expanding helminthiasis caused by the trematode Fasciola hepatica. Sheep and cattle are the primary definitive hosts of F. hepatica and are economically significant hosts for this pathogen worldwide. F. hepatica is not only a major threat to livestock but also an important neglected zoonosis. Reports of anthelmintic resistance in F. hepatica emphasize the urgent need for the development of an effective vaccine. Such a vaccine would reduce the impact and spread of the disease by decreasing the number of viable eggs, as well as reducing the adult worm population, ultimately leading to less liver damage. In a previous study, we demonstrated the ability of the F. hepatica Kunitz-type molecule synthetic (sFhKTM), formulated with a liquid crystal nanostructure created through the self-assembly of 6-O-ascorbyl palmitate ester (Coa-ASC16) and the synthetic oligodeoxynucleotide containing unmethylated cytosine-guanine motifs (CpG-ODN) to provide protection against F. hepatica in infected mice. In this study, we assessed the efficacy of the vaccine sFhKT/CpG-ODN/Coa-ASC16 in sheep. The formulation containing the highest sFhKT dose was the most effective, significantly reducing fecal egg counts by 81.6 % (p < 0.0001). It also reduced worm burden by 55.7 % (p = 0.179), although this difference was not statistically significant. The addition of Cathepsin L3 (FhCL3) further reduced fecal egg counts (89.1 %, p < 0.0001) but resulted in a lower reduction in worm burden (24.06 %). Sheep vaccinated with sFhKT/CpG-ODN/Coa-ASC16 exhibited slightly less hepatic damage than non-vaccinated animals, with histological lesions characterized by increased inflammatory infiltrates. The experimental vaccine FhKT/CpG-ODN/Coa-ASC16 induced non-significantly greater IgG titers in immunized sheep compared to non-vaccinated controls. The variation in efficacy observed between the sFhKT doses highlights the need for additional trials using higher protein concentrations.

片形吸虫病是由肝片形吸虫引起的一种广泛且持续扩大的寄生虫病。羊和牛是肝芽胞杆菌的主要最终宿主，在世界范围内是这种病原体的重要经济宿主。肝梭菌不仅是家畜的主要威胁，也是一种被忽视的重要人畜共患病。关于肝单胞菌抗虫虫的报告强调了开发有效疫苗的迫切需要。这种疫苗将通过减少活虫卵的数量以及减少成虫数量来减少疾病的影响和传播，最终减少肝脏损伤。在之前的一项研究中，我们证明了肝F. kuniz型分子合成（sFhKTM）的能力，该分子合成是通过6- o -抗坏血酸棕榈酸酯（Coa-ASC16）和含有未甲基化胞嘧啶-鸟嘌呤基序（CpG-ODN）的合成寡脱氧核苷酸自组装而成的液晶纳米结构，可以在感染的小鼠中提供对肝F.的保护。在这项研究中，我们评估了sFhKT/CpG-ODN/Coa-ASC16疫苗在绵羊中的功效。含有最高sFhKT剂量的配方最有效，显著减少粪蛋计数81.6 % （p <； 0.0001）。它还减少了55.7% % （p = 0.179）的蠕虫负担，尽管这种差异没有统计学意义。添加Cathepsin L3 （FhCL3）进一步降低了粪卵计数（89.1% %,p <； 0.0001），但导致蠕虫负荷降低（24.06% %）。与未接种sFhKT/CpG-ODN/Coa-ASC16疫苗的绵羊相比，接种sFhKT/CpG-ODN/Coa-ASC16疫苗的绵羊肝脏损伤略轻，组织学病变以炎症浸润增加为特征。实验疫苗FhKT/CpG-ODN/Coa-ASC16诱导免疫绵羊的IgG滴度比未接种疫苗的对照组无显著性升高。sFhKT剂量之间观察到的疗效差异强调了使用更高蛋白质浓度进行额外试验的必要性。

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引用次数: 0

Comparative efficacy of herbal extracts and separately bakuchiol against the monogenean parasite Gyrodactylus kobayashii in goldfish 草药提取物与单独木酚对金鱼单系寄生虫小林旋毛虫的防治效果比较

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-02-01 Epub Date: 2025-12-29 DOI: 10.1016/j.vetpar.2025.110684

Xialian Bu , Yulong Liu , Xianqi Peng , Lei Huang , Weisong Ma , Jing Chen , Chen Niu , Xiaofeng Shan , Jiayun Yao

Species of Gyrodactylus are common monogenean ectoparasites infecting both freshwater and marine fish. Their rapid proliferation and high transmissibility make them a serious threat to aquaculture. Current chemical treatments have drawbacks of drug residues and high resistance, requiring the discovery of safe and environmentally friendly alternatives. In this study, anthelmintic efficacy against Gyrodactylus kobayashii of eight herbal medicines was evaluated. One of the components bakuchiol from Psoralea corylifolia showed the best anthelmintic efficacy. The in vitro assays showed a positive correlation between bakuchiol concentrations and the mortality of G. kobayashii, with 100 % mortality at 8 mg/L and 1 h exposure. The in vivo anthelmintic efficiency also exhibited a concentration-dependent relationship, treatment with bakuchiol at 6 mg/L for 48 h resulted in 100 % mortality. The EC₅₀ and EC₉₀ values after 48 h exposure were 2.93 and 5.17 mg/L, respectively. Besides, the result of acute toxicity test showed its safety in goldfish, with the 96 h LC₅₀ value of 45.85 mg/L. Additionally, the results of scanning electron microscopy and transmission electron microscopy showed that bakuchiol induced severe ultrastructural damage to G. kobayashii, including tegument disruption, mitochondria swelling, and myofilaments reduction. Histopathological analysis indicated that G. kobayashii were detached from gills of goldfish after bakuchiol exposure. Overall, these findings demonstrated the potential of bakuchiol as an alternative treatment for controlling gyrodactylid infections.

旋毛虫是一种常见的单系外寄生虫，可感染淡水和海鱼。它们的快速繁殖和高传播性使它们对水产养殖构成严重威胁。目前的化学处理方法存在药物残留和耐药性高的缺点，需要寻找安全环保的替代方法。本研究对8种中药对小林旋毛虫的驱虫效果进行了评价。补骨脂的其中一种化学成分bakuchiol的驱虫效果最好。体外实验表明，木酚浓度与小林田鼠的死亡率呈正相关，在8 mg/L和1 h时死亡率为100% %。体内驱虫效率也表现出浓度依赖关系，6 mg/L bakuchiol处理48 h，死亡率为100% %。48 h后的EC50和EC90值分别为2.93和5.17 mg/L。急性毒性试验结果表明其对金鱼是安全的，96 h LC50值为45.85 mg/L。此外，扫描电镜和透射电镜结果显示，桃木酚引起了严重的超微结构损伤，包括被皮破坏、线粒体肿胀和肌丝减少。组织病理学分析表明，金鱼暴露于白苦酚后，鱼鳃中游离出小林氏菌。总的来说，这些发现证明了bakuchiol作为控制回转体感染的替代治疗方法的潜力。

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引用次数: 0

Cutaneous changes and cellular infiltration in response to tick attachment in Namaqua Afrikaner, Dorper and South African Mutton Merino sheep 纳马夸阿非利卡羊、杜珀羊和南非美利奴羊对蜱虫附着反应的皮肤变化和细胞浸润。

IF 2.2 2区农林科学 Q2 PARASITOLOGY

Veterinary parasitology

Pub Date : 2026-01-01 Epub Date: 2025-10-31 DOI: 10.1016/j.vetpar.2025.110640

K. Thutwa , J.B. van Wyk , K. Dzama , P.T. Muvhali , S.W.P. Cloete

Host immune reaction to tick infestation is crucial for minimizing parasite burdens and reducing the transmission of pathogens, ultimately improving livestock health, welfare and productivity. It is unclear how divergent sheep breeds respond to tick infestation in South Africa. This study explored local cutaneous cellular immune responses in to tick infestation, a critical factor in reducing parasite burdens, limiting disease transmission, and improving livestock health, welfare and productivity. Breed-specific differences in cellular infiltration and skin responses at tick attachment and adjacent non-attachment sites were studied in 89 mature ewes maintained in the same flock. In total, 21 Namaqua Afrikaner (NA), 29 South African Mutton Merino (SAMM) and 39 Dorper ewes were used. Skin biopsies per ewe from both tick attachment and non-attachment control sites were analyzed histologically. The results showed marked variation in immune responses within and between breeds. Although skin changes were generally more pronounced at tick attachment sites across all breeds, four skin defects (spongiosis, apopthosis, necrosis and collagen degeneration) in the NA breed showed no difference between sites. All breeds exhibited similar frequencies of skin defects at tick attachment sites. Cellular infiltration was more common at tick attachment sites, with the NA and SAMM breeds showing more pronounced leukocyte infiltration than the Dorper breed. Notably, basophils, mast cells, and eosinophils were more frequently observed at tick attachment sites in NA sheep compared to the Dorper, followed by occasional increases in the SAMM breed. These findings highlight divergent breed-related immune responses to tick infestation and underscore the role of specific immune cells in mediating resistance, with the NA showing an enhanced response to tick attachment.

宿主对蜱虫侵害的免疫反应对于减少寄生虫负担和减少病原体传播，最终改善牲畜健康、福利和生产力至关重要。目前尚不清楚不同的绵羊品种如何应对南非的蜱虫侵扰。本研究探讨了局部皮肤细胞对蜱虫侵袭的免疫反应，这是减少寄生虫负担、限制疾病传播和改善牲畜健康、福利和生产力的关键因素。以89只母羊为研究对象，研究了不同品种间蜱虫附着和非附着部位细胞浸润和皮肤反应的差异。总共使用了21只纳马卡阿非利卡羊（NA）、29只南非美利奴羊（SAMM）和39只杜珀母羊。每只母羊的皮肤活检，从蜱虫附着和非附着的对照部位进行组织学分析。结果显示，不同品种之间和品种内部的免疫反应有显著差异。尽管所有品种的蜱虫附着部位的皮肤变化通常更为明显，但NA品种的四种皮肤缺陷（海绵状病、细胞凋亡、坏死和胶原变性）在不同部位之间没有差异。所有品种在蜱虫附着部位出现皮肤缺陷的频率相似。细胞浸润在蜱虫附着部位更为常见，NA和SAMM品种比Dorper品种表现出更明显的白细胞浸润。值得注意的是，与杜珀羊相比，NA羊在蜱虫附着部位更频繁地观察到嗜碱性粒细胞、肥大细胞和嗜酸性粒细胞，随后在SAMM羊中偶尔增加。这些发现强调了不同品种对蜱虫侵害的不同免疫反应，并强调了特异性免疫细胞在介导抗性中的作用，NA对蜱虫附着的反应增强。

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引用次数: 0