Browsing by Subject "Metabarcoding"

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    Impact of whole-herd vaccination on a caprine coxiellosis outbreak: a longitudinal study of Coxiella burnetii shedding, serology, and host microbiota
    (Frontiers Media, 2026-06-03) Toledo-Perona, Raquel; Gomis, Jesús; Bailon-Larrañaga, Nerea; Contreras de Vera, Antonio; Quereda, Juan José; González-Torres, Pedro; Carrón, Nerea; Gómez Marín, Ángel; Sanidad Animal
    This longitudinal study investigated C. burnetii dynamics and the associated microbiota after vaccination in aborted and normal-delivery goats and bucks following a Q fever outbreak. Fecal, milk, vaginal, preputial, nasopharyngeal, environmental (qPCR and 16S rRNA), and blood samples (16S rRNA and serology) were analyzed. Before vaccination, over 70% of animals were seropositive, with qPCR positivity in all females and half of the males. Seroconversion remained complete until the second kidding season and reached approximately 90% by the third kidding season. After primary vaccination, a significant 60% reduction in shedders was observed, with shedding remaining absent during the two consecutive kidding seasons. Nasopharyngeal samples showed the highest and most persistent positivity, highlighting their diagnostic and epidemiological relevance. The first detection of C. burnetii in the buck prepuce underscores the potential role of males in disease maintenance. Persistent environmental contamination further supports early, whole-herd vaccination as a long-term strategy. Metabarcoding revealed significant shifts in microbial diversity across all anatomical sites over time, including vaginal community structure, suggesting local dysbiosis after abortion. The DNA detection of C. burnetii in blood and its significantly higher vaginal abundance in aborted females may contribute to abortion. A reduction in vaginal pathogen load (p < 0.05) may suggest a reproductive microbiota modulation associated with increased Firmicutes, considering it as a potentially health biomarker.
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    Open Access
    Testicular ultrasound patterns, sperm quality, seminal microbiota, caprine arthritis encephalitis virus and Coxiella burnetii infection in bucks
    (Elsevier, 2026-04-25) Bailón-Larrañaga, N.; Gomis, J.; Contreras de Vera, Antonio; Toledo-Perona, R.; Toquet, M.; Reyes, L.E.; Quereda, J.J.; Gonzalez-Torres, P.; Gñpmez-Marín, A.; Sanidad Animal
    This study assesses the frequency and severity of ultrasound-detected testicular alterations across age groups (young and adult) in 219 bucks. Sperm quality and testicular echotexture were evaluated, and their associations with reproductive pathogens (Coxiella (C.) burnetii, caprine arthritis encephalitis virus (CAEV), Chlamydia (C.) abortus and Mycoplasma (M.) agalactiae) were analyzed. Additionally, qPCR was also performed on ejaculates from seropositive bucks. Seminal microbiota was characterized in three groups: 1 (seronegative without lithiasis), 2 (seropositive with lithiasis), and 3 (qPCR-CAEV-positive). A 68.5% of bucks showed testicular microlithiasis (50.2% bilateral and 18.2% unilateral). Moreover, frequency of bilateral lesions differed according to age, being higher in adults, who also showed larger microlithiasis area (P < 0.05). Age was negatively correlated with sperm concentration (P < 0.05). Seropositivity was 35.8% for C. burnetii and 58.8% for CAEV. Adults showed higher CAEV seropositivity (P < 0.001), and 4.2% of ejaculates tested qPCR positive for this pathogen. Bacterial richness was greater (P < 0.001) in group 2 than in group 1. Firmicutes dominated groups 1 and 2, whereas Fusobacteriota prevailed in group 3. The most frequent genus in all three experimental groups was Oceanivirga, with higher abundance in group 1 than in group 2 (P < 0.05). These findings suggest that ejaculate microbiota may be influenced by ultrasound abnormalities and exposure to CAEV and C. burnetii, supporting the use of testicular ultrasound to detect bucks prone to reproductive problems and associated health risks, while also highlighting the need to include males in CAE and Q fever control programs.