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Genomic insights into Shigella species isolated from small ruminants and manure in the North West Province, South Africa.

This study investigated Shigella species' antibiotic resistance patterns and genomic characteristics from small ruminants and manure collected in Potchefstroom, North West, South Africa. Whole genome sequencing was used to determine resistome profiles of Shigella flexneri isolates from small ruminants' manure and Shigella boydii from sheep faeces. Comparative genomics was employed on the South African 261 S. flexneri strains available from GenBank, including the sequenced strains in this study, by investigating the serovars, antibiotic resistance genes (ARGs), and plasmid replicon types. The S. flexneri strains could not be assigned to known sequence types, suggesting novel or uncharacterized lineages. S. boydii R7-1A was assigned to sequence type 202 (ST202). Serovar 2A was the most common among South African S. flexneri strains, found in 96% of the 250 compared human-derived isolates. The shared mdf(A) was the most prevalent gene, identified in 99% of 261 S. flexneri genomes, including plasmid replicon types ColRNAI_1 (99%) and IncFII_1 (98%). Both species share a core set of resistance determinants mainly involving β-lactams (ampC1, ampC, ampH), macrolides (mphB), polymyxins (eptA, pmrF), multidrug efflux pumps (AcrAB-TolC, Mdt, Emr, Kpn families), and regulatory systems (marA, hns, crp, baeRS, evgAS, cpxA, gadX). However, S. boydii possesses additional resistance genes conferring resistance to tetracyclines (tet(A)), phenicols (floR), sulphonamides (sul2), and aminoglycosides (APH(3'')-Ib, APH(6)-Id), along with the acrEF efflux pump components (acrE, acrF). In contrast, S. flexneri harboured unique genes linked to polymyxin resistance (ugd) and regulatory functions (sdiA, gadW) that were absent in S. boydii. These findings highlight Shigella strains' genomic diversity and antimicrobial resistance potential in livestock-associated environments. Moreover, S. boydii highlights the potential risk of multidrug-resistant bacteria in farming and environmental routes. KEY POINTS: • First whole genome study of Shigella from manure and small ruminants in South Africa. • Shigella boydii strain carried multiple resistance genes to β-lactams and tetracycline. • Multidrug efflux pump gene mdf(A) was detected in 99% of South African Shigella flexneri strains.

Animals

Clinical and Microbiological Insights into Caseous Lymphadenitis in Sheep and Goats in Khorasan Razavi, Iran.

INTRODUCTION: Caseous lymphadenitis (CLA), a chronic bacterial disease caused by Corynebacterium pseudotuberculosis, significantly impacts small-ruminant health and productivity worldwide, causing economic losses through reduced wool and milk yields, reproductive issues, and carcass condemnation. Despite its importance, CLA prevalence and microbial dynamics remain under explored in Iran, where small ruminants are vital to rural economies. This study assessed the prevalence, clinical manifestations, and bacteriological profile of CLA in Khorasan Razavi Province, northeast Iran, to inform regional control strategies and address potential zoonotic risks. MATERIALS & METHODS: We examined 15 flocks totaling 4,733 animals (4,640 sheep, 93 goats) through clinical inspections and microbiological analysis of pus samples from affected lymph nodes. RESULTS: The results revealed a lymphadenitis prevalence of 11.59% (95% CI, 10.58%, 12.66%), with 8.62% of sheep (400/4640) and 8.60% of goats (8/93) affected, varying across flocks from 0% to 28.57%. Submandibular lymph nodes were most commonly affected (51.35%), followed by retropharyngeal (18.02%) and parotid (15.32%) nodes, with peak incidence in the 2-3-year age group (38.24%), likely linked to shearing practices. Bacteriological analysis of 102 pus samples identified C. pseudotuberculosis in 19.6% (20/102) of cases, characterized by small, dry, white colonies with β-hemolysis on Columbia blood agar. A diverse microbial profile included Actinobacillus spp. (7.8%), Trueperella pyogenes (3.9%), and novel isolates like Acinetobacter spp. and Yersinia spp. (1.0% each), with 43.14% of samples sterile, suggesting chronicity or sampling challenges. CONCLUSION: These findings indicate CLA etiology is complex, extending beyond a single pathogen and influenced by local husbandry practices. The study underscores CLA's economic burden and zoonotic potential, given rare but documented human cases. Integrated control measures-enhanced molecular diagnostics, recombinant phospholipase D (PLD) vaccine trials, and improved biosecurity-are urgently needed. Future research should prioritize genomic strain typing and environmental reservoir analysis to refine CLA management in Northeast Iran, offering insights applicable to similar agroecosystems globally.

Animals

A genetic manipulation tool based on the GP35 recombinase for targeted gene editing in mycoplasmas of ruminants.

Pathogenic ruminant mycoplasmas are major etiological agents in cattle and small ruminants and are responsible for substantial economic losses in the livestock industry. Progress in pathogenesis research and vaccine development has been hampered by a lack of effective genetic tools. The applicability of common genome editing platforms, such as CRISPR, is inherently restricted in these organisms owing to their minimal genomes, the absence of a cell wall, and low homologous recombination efficiency. Although transposon-mediated random mutagenesis and single-base editing are currently used in the editing of bovine mycoplasma, the stochastic nature of transposons, the risk of single-base random deamination, and limitations in editing window selection hinder the genetic manipulation of bovine mycoplasma. Here, we introduce a plasmid-based methodology that employs the GP35 recombinase from bacteriophage SPP1 to mediate long single-stranded DNA (ssDNA) recombineering, thereby enabling precise gene insertions and deletions in Mycoplasma bovis, with a positive-editing rate of 77.78% - 100%. This targeted system eliminates the risk of random deamination. Leveraging this tool, we generated a panel of M. bovis mutants affecting metabolic and virulence genes and obtained key insights into Mb0564, identified as a novel adhesin. The 192 to 287 aa region of GP35 is critical for interaction with SSB. Structural conservation analysis further suggested that this GP35-ssDNA editing system possesses a high potential for translation to other ruminant pathogens. Collectively, our approach expands the existing genetic toolkit for M. bovis, advances synthetic biology and M. bovis pathobiology, facilitates vaccine development, and strengthens the control of high-impact livestock diseases in line with the One Health framework.

Animals

In vitro EVALUATION OF Beauveria bassiana ISOLATES AGAINST GASTROINTESTINAL NEMATODES FROM GOATS.

Biological control has emerged as a promising alternative for the control of gastrointestinal nematodes in small ruminants. However, additional information is still needed on the nematicidal portencial of Beauveria bassiana and on the early interaction between fungal conidia and infective larvae. In this study, six B. bassiana isolates (LCMS19-LCMS24) were evaluated in vitro using a coproculture assay with fecal samples from naturally infected goats. Larval recovery was compared with that of an untreated control to estimate the percentage reduction in third-stage larvae (L3). The most effective isolate was subsequently examined by scanning electron microscopy (SEM) to characterize its interaction with L3. All isolates reduced L3 recovery compared with the control, although their efficacy differed. LCMS21 showed the greatest reduction in L3 recovery and differed significantly from the other treatments. SEM revealed extensive adhesion of LCMS21 conidia to the L3 cuticle, in the anterior and median regions. However, no clear evidence of conidial germination, germ tube formation, cuticle penetration, or hyphal development was observed after 48 or 72 h. These results indicate that B. bassiana isolates differ in their in vitro activity against gastrointestinal nematodes and identify LCMS21 as the most promising isolate among those tested. The ultrastructural observations support an early fungus-larva interaction, but they do not allow the nematicidal effect to be attributed to adhesion. Further studies are needed to clarify the mechanisms involved and to evaluate the potencial application of this isolate in integrated parasite control programs.

Beauveria bassiana

Genomic insights into the population history of fat-tailed sheep and identification of two mutations that contribute to fat tail adipogenesis.

INTRODUCTION: Since their domestication, domestic sheep (Ovis aries) have been culturally and economically significant farming animals worldwide. Fat-tailed sheep serve as a unique genetic resource for understanding adipogenesis and adaptive evolution in livestock. OBJECTIVES: Several genomic analyses have been conducted on various sheep breeds to elucidate the genome and regulation mechanism of the fat tail trait, prior genomic studies have failed to reconcile conflicting evidence about the genetic basis of tail morphology, particularly regarding the roles of PDGFD and BMP2. METHODS: Here, we conducted whole-genome resequencing of 283 sheep, encompassing 66 domestic breeds and 5 wild ovine species, to investigate the domestication history and selection signatures of fat-tailed sheep. Additionally, we performed transcriptome sequencing on adipose tissue to identify differentially expressed genes and cellular assays to validate these results. RESULTS: Demographic analysis revealed that domestic sheep descended from Asiatic mouflon and fat-tailed sheep began to diverge from thin-tailed sheep approximately 4.4-7.5 thousand years ago in East Asia. Chinese indigenous sheep were classified into Mongolian, Kazakh, Tibetan, and Yunnan populations. The Yunnan population may have experienced more recent genetic introgression from wild species, rather than an independent domestication event. Moreover, many potential regions associated with the fat-tailed phenotype (DDI1, PDGFD, and BMP2) were identified by selective sweep and genome-wide association analyses. Additionally, a fine-scale analysis of fat-tailed and thin-tailed sheep revealed two novel mutations: a G/A missense variant of PDGFD (Chr15: 3900312) and a C/T missense variant of BMP2 (Chr13: 48462350), both of which were significantly associated with tail adiposity. Functional validation demonstrated that mutant A-PDGFD significantly activated PFGFD expression and reduced fat deposition compared to wildtype. The C-BMP2 mutant activated BMP2 expression and promoted preadipocyte fat deposition. CONCLUSION: Our study provides the first evidence that these genes jointly regulate fat tail development through complementary mechanisms: PDGFD promotes adipose expansion, whereas BMP2 modulates energy partitioning. These findings offer new insights into the evolutionary history of fat-tailed sheep and identify potential targets for precision breeding in small ruminants.

Animals

Prevalence of Theileria luwenshuni in goats (Capra hircus) on Tarama Island, Okinawa, Japan.

Caprine theileriosis is an economically important tick-borne disease caused by various Theileria species, particularly Theileria lestoquardi, Theileria luwenshuni, and Theileria uilenbergi, in goats (Capra hircus). Goat farming plays an economically and culturally important role on Tarama Island, Okinawa, Japan. Because goats on the island are mainly managed under an extensive grazing system, tick infestation is common. However, Theileria infections have not previously been investigated in goats on Tarama Island. To address this, archived DNA samples prepared from blood collected from 44 goats on Tarama Island were screened using a universal PCR assay targeting 18S rRNA sequences of Theileria and Babesia species. Two DNA samples were positive, and sequencing analysis of the amplicons identified T. luwenshuni. To further investigate the epidemiology of T. luwenshuni on Tarama Island, blood samples were subsequently collected from 96 goats across 19 farms. From each blood sample, a thin blood smear was prepared and genomic DNA was extracted. Microscopic examination of Diff-Quik-stained smears detected intraerythrocytic Theileria-like organisms in 35 (36.5%) goats. In addition, screening of DNA samples using a newly developed T. luwenshuni-specific PCR assay detected 77 (80.2%) positive goats, and the subsequent sequencing analysis confirmed the PCR results. Given that T. luwenshuni can cause severe disease in small ruminants, our findings highlight the importance of managing T. luwenshuni infection in goats on Tarama Island.

Animals

Molecular epidemiology and phylogenetic analysis of Anaplasma ovis and Anaplasma marginale in Ixodidae infesting livestock in northwestern Iran.

BACKGROUND: Anaplasma marginale and Anaplasma ovis are tick-borne obligate intracellular bacteria causing anaplasmosis in cattle and small ruminants, respectively, with considerable economic losses worldwide. Given the favorable ecological conditions for tick survival and the limitation of data on Anaplasma spp. in local tick populations in northwestern Iran, this study aimed to molecular and phylogenetic analysis of A. ovis and A. marginale in Ixodidae infesting livestock in northwestern Iran. METHODS: In this cross-sectional study, a total of 780 ixodid ticks were collected from livestock across 198 herds in 11 counties of Ardabil Province during 2025. Ticks were morphologically identified and grouped into pools based on species and host type. Genomic DNA was extracted using a commercial kit and molecular detection of A. ovis and A. marginale was performed using PCR assays targeting the 16&#xa0;S rRNA and groEL genes. Positive samples were submitted for Sanger sequencing to confirm the identity of Anaplasma spp., phylogenetic analysis was conducted using reference sequences from GenBank (NCBI) using MEGA software (version 12). Statistical analyses were conducted using SPSS (version 25), and associations between categorical variables were assessed using Fisher's exact test (p < 0.05). RESULTS: Eight tick species belonging to three genera were identified. Among the hosts, sheep exhibited the highest infestation rate (49.3%). Hyalomma anatolicum anatolicum was the most prevalent species (25.3%) and was present in all sampled counties. Tick distribution varied significantly among host species (p = 0.003) and geographic locations (p = 0.002). PCR analysis detected A. ovis DNA in 16.6% (4/24) and A. marginale DNA in 8.3% (2/24) of tick pools. Positive pools were primarily associated with Rhipicephalus spp. and Dermacentor marginatus. According to the results of the statistical analysis a significant association was found between tick species and host type (&#x3c7;&#xb2; = 13.87, p = 0.0031), with Hyalomma anatolicum anatolicum more prevalent in sheep (p = 0.001). Tick abundance varied across counties (&#x3c7;&#xb2; = 16.42, p = 0.002), with highest densities in Nir, Khalkhal, and Kowsar (&#x3c7;&#xb2; = 14.21, p = 0.0028). No significant association was observed between Anaplasma positivity and tick species (p = 0.21) or host type (p = 0.09). CONCLUSIONS: The detection of A. ovis and A. marginale DNA in ixodid tick pools indicates their circulation in Ardabil Province. However, due to pooled sampling and the limited number of positive samples, the infection rate at the individual tick level could not be determined. These findings also highlight the importance of a One Health approach, considering the interconnected roles of animal health, tick vectors, and the environment in the transmission and control of tick-borne diseases.

Animals

Expression profiles of miRNAs in ruminant intermediate hosts with cystic echinococcosis.

Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus sensu lato (s.l.), is a parasitic zoonotic disease recognized by the World Health Organization as a neglected tropical disease of significant public health concern. Despite ongoing control programs, CE remains endemic, underlining the need for integrated control strategies that involve new diagnostic and therapeutic tools. Recent investigations have spotlighted microRNAs (miRNAs) as key regulators in parasite development, immunomodulation, and as potential diagnostic and therapeutic targets. In the present research, a molecular study was conducted to investigate hydatid cyst samples (protoscoleces and germinal membranes) collected in southern Italy from different ruminant species (sheep, cattle, and water buffaloes), naturally infected with CE, with the ultimate goal of establishing a more comprehensive picture of miRNA expression patterns in these intermediate hosts. The bioinformatic analysis of hydatid cyst samples revealed 168 mature miRNAs. Among these, egr-miR-10-5p, egr-let-7-5p, and egr-miR-71-5p were the most abundant, with egr-miR-10-5p showing particularly high expression levels. No significant differences in miRNA abundance between host species were found. In contrast, when focusing on the comparison between protoscoleces and sterile germinal membranes, 24 miRNAs were found to be differentially expressed. Targeted qPCR of four selected miRNAs (egr-miR-71-5p, egr-let-7-5p, egr-miR-125-5p, and egr-miR-10-5p) showed clear overexpression in protoscoleces and in fertile germinal membranes compared with sterile ones. The differential miRNA expression patterns provide insight into the molecular mechanisms controlling the parasite's lifecycle and may guide the development of novel intervention methods to enhance CE control in endemic areas.

Animals

Mediators of Change in Cognitive Behavioral and Mindfulness-Based Online-Interventions for Hypoactive Sexual Desire Dysfunction in Women.

Low sexual desire is a common sexual problem among women. When it is accompanied by significant personal distress, it may be diagnosed as hypoactive sexual desire dysfunction (HSDD). Both cognitive behavioral therapy (CBT) and mindfulness-based therapy (MBT) are effective treatments for HSDD when delivered in person or online. In this randomized controlled treatment study, CBT and MBT consisted of eight guided self-help modules delivered online, and participants completed measures at pretreatment and after 3, 6, and 12&#x2009;months. Nine variables were examined as potential mediators of treatment outcomes (i.e., sexual desire and sexual distress), namely mindfulness, self-compassion, rumination, body connection, self-consciousness, relationship satisfaction, sexual communication, depression, and anxiety. In total, 212 women diagnosed with HSDD were randomized to either CBT or MBT (Mage&#x2009;=&#x2009;36.3, SD&#x2009;=&#x2009;10.2). Improvements in self-compassion, rumination, body connection, and self-consciousness partially mediated treatment outcomes in at least one of the treatment groups. Mediation effects were mostly small, explaining up to 15% of the total effects. No systematic differences in mediation pathways between CBT and MBT were found. These findings emphasize the importance of emotion regulation, metacognitive processes, and embodiment for the effective treatment of HSDD. Future research should refine treatment components to enhance efficacy and ensure that psychological interventions adequately address common concerns among women with HSDD.

Humans

Spatiotemporal patterns of Rift Valley fever virus in Africa: a retrospective genomic epidemiology and phylodynamic modelling study.

BACKGROUND: Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing outbreaks in humans and ruminants across Africa and the Arabian Peninsula. Originally restricted to the Great Rift Valley, RVFV has expanded geographically, prompting its classification by WHO as a pathogen of pandemic potential. We investigated the evolutionary and spatial dynamics of RVFV across Africa. METHODS: We used genomic data generated at the International Livestock Research Institute Nairobi genomic laboratory (BioProject PRJNA1106221) and combined with publicly available datasets retrieved from the National Center for Biotechnology (NCBI) GenBank nucleotide database. In retrieving RVFV genome sequences from the NCBI GenBank, we applied the search terms "Rift Valley fever virus segment L AND 6404[SLEN]", "Rift Valley fever virus segment M AND 3885[SLEN]", and "Rift Valley fever virus segment S AND 1520:1690[SLEN]" for L (Large), M (Medium), and S (Small) segments, respectively. For sequences without additional spatiotemporal information, we searched PubMed to extract the associated sequence metadata. We performed molecular clock analysis, phylogenetic inference, phylodynamic modelling (continuous phylogeographic reconstruction), and landscape phylogeography on the three RVFV genome segments (L, M, and S). We aimed to assess evolutionary rates, dispersal patterns, and environmental drivers. Focus was placed on lineage C, the most widely distributed variant. FINDINGS: The global dataset used in this study consisted of large (n=236), medium (n=237), and small (n=247), which were further filtered to exclude potential reassortants and vaccine strains. Genome sequences retrieved from NCBI GenBank database comprised large (n=180), medium (n=184), and small (n=202). The genome sequences from retrospective human and livestock isolates comprised large (n=56), medium (n=53), and small (n=45) collected in Burundi (2018), Kenya (2007, 2018, 2019, 2021, and 2022), and Rwanda (2018 and 2022). Our dataset revealed that RVFV exhibited low overall genetic diversity. Lineage C, however, showed evidence of active evolution, with substitution rates ranging from 3&#xb7;58&#x2009;&#xd7;&#x2009;10-4 to 9&#xb7;76&#x2009;&#xd7;&#x2009;10-4 substitutions per site per year. This lineage probably originated in Zimbabwe in the mid-1970s and has since expanded across eastern and southern Africa. Phylogeographic reconstructions revealed rapid spread, with diffusion coefficients exceeding 50&#x2009;000 km2 per year. INTERPRETATION: Lineage C appears capable of establishing endemic transmission in new regions, with ongoing diversification observed during interepidemic periods. These observations reinforce the value of continuous genomic surveillance, particularly during cryptic transmission phases when adaptive mutations might emerge. Although further evidence is needed, observed trends in climate variability and land-use change point to the potential benefit of targeted surveillance in settings that could be at increased risk, including urban centres and wetlands. FUNDING: This work was supported by the German Federal Ministry for Economic Cooperation and Development, the Rockefeller Foundation, and the Africa Centres for Disease Control and Prevention.

Rift Valley fever virus