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Gómez Martín, Ángel

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Facultad de Veterinaria / Vicerrectorado de Investigación

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Now showing 1 - 10 of 19
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    UCH
    Vaginal microbiota changes during estrous cycle in dairy heifers2020-07-03

    The vaginal microbiota plays an important role in the health of dairy cattle, and it could be manipulated for the prevention and treatment of reproduction-related infections. The present study profiles and compares the vaginal microbiota of healthy dairy heifers during the estrous cycle focusing the results in follicular (estrus) and luteal (diestrus) phases using 16S rRNA sequencing of the V3–V4 hypervariable region. Twenty 13–16-months-old virgin dairy heifers from a single farm were included in this study. Vaginal swabs and blood samples were obtained during estrus (6–8 h before artificial insemination) and diestrus (14 days after insemination). Estrus was evaluated by an activity monitoring system and confirmed with plasma progesterone immunoassay. Results showed that the taxonomic composition of the vaginal microbiota was different during the follicular and luteal phases. At the phylum level, the most abundant bacterial phyla were Tenericutes, Firmicutes, and Bacteroidetes which comprised more than 75%of the vaginal microbiota composition. The next more abundant phyla, in order of decreasing abundance, were Proteobacteria, Actinobacteria, Fusobacteria, Epsilonbacteraeota, and Patescibacteria. Together with Tenericutes, Firmicutes, and Bacteroidetes represented more than 96% of the bacterial composition. Ureaplasma, Histophilus, f_Corynebacteriaceae, Porphyromonas, Mycoplasma, Ruminococcaceae UCG-005, were the most abundant genera or families. The results also showed that the vaginal microbiota of dairy heifers was non-lactobacillus dominant. The genus Lactobacillus was always found at a low relative abundance during the estrous cycle being more abundant in the follicular than in the luteal phase. Despite more research is needed to explore the potential use of native vaginal microbiota members as probiotics in dairy heifers, this study represents an important step forward. Understanding how the microbiota behaves in healthy heifers will help to identify vaginal dysbiosis related to disease.

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    UCH
    Vaginal microbiota is stable throughout the estrous cycle in Arabian mares2020-11-03

    Lactic acid bacteria (LAB) dominate human vaginal microbiota and inhibit pathogen proliferation. In other mammals, LAB do not dominate vaginal microbiota, however shifts of dominant microorganisms occur during ovarian cycle. The study objectives were to characterize equine vaginal microbiota in mares by culture-dependent and independent methods and to describe its variation in estrus and diestrus. Vaginal swabs from 8 healthy adult Arabian mares were obtained in estrus and diestrus. For culture-dependent processing, bacteria were isolated on Columbia blood agar (BA) and Man Rogosa Sharpe (MRS) agar. LAB comprised only 2% of total bacterial isolates and were not related to ovarian phases. For culture-independent processing, V3/V4 variable regions of the 16S ribosomal RNA gene were amplified and sequenced using Illumina Miseq. The diversity and composition of the vaginal microbiota did not change during the estrous cycle. Core equine vaginal microbiome consisted of Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria at the phylum level. At the genus level it was defined by Porphyromonas, Campylobacter, Arcanobacterium, Corynebacterium, Streptococcus, Fusobacterium, uncultured Kiritimatiaellae and Akkermansia. Lactobacillus comprised only 0.18% of the taxonomic composition in estrus and 0.37% in diestrus. No di erences in the relative abundance of the most abundant phylum or genera were observed between estrus and diestrus samples.

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    UCH
    Short-term economic impact of COVID-19 on Spanish small ruminant flocks2020-08-05

    The human pandemic COVID-19 caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) started in China in 2019 and has rapidly spread around the world, leading to extreme control measures such as population confinement and industry activity closure. Although small ruminants are not sanitary a ected by this virus, the short-term economic impact derived by COVID-19 on Spanish flocks is estimated in this study, using data provided by producers and two major slaughterhouses. Milk prices of dairy goat flocks su ered a substantial drop in April 2020, close to 4.5 cts EUR/liter compared to the previous month. In contrast, the monthly milk prices in sheep remained almost stable during this period, and even increases of more than EUR 6 cts were reported in comparison with the previous year. Nevertheless, economical di erences are reported by areas where producers could receive a higher income, close to EUR 0.3 per liter of milk. Global data provided by feedlots a ecting 2750 Spanish flocks evidenced a lamb price drop ranging from 16.8% to 26.9% after the pandemic arrival; in line with the data directly reported by a limited sample of producers (ranging from 11.0% to 23.7%). The goat kid meat market also su ered a reduction in prices per kg, near 12.5%; although, for some flocks, losses reached up to 40%. In the same line, 2 slaughterhouses reported a sudden sacrifice drop around 27% for lambs and goat kids sacrifices in April, in contrast with the usual sacrifice figures from the beginning of 2020. Moreover, our study showed a temporary and unexpected retention of lambs and goat kids at farms due to a reduction in animals slaughtered during this period. In conclusion, data evidenced a considerable negative economic impact on Spanish small ruminant flocks, throughout the first 60 days after COVID-19’s pandemic declaration. Further studies are needed to evaluate the long-term economic consequences, in order to establish contingency plans and avoid the collapse of small ruminant industries when a crisis of these characteristics occurs.

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    UCH
    Search of antimicrobial lactic acid bacteria from "Salmonella"-negative dogs2022-01-03

    Background: Salmonellosis is one of the most important food-borne zoonotic disease affecting both animals and humans. The objective of the present study was to identify gastrointestinal (GI) lactic acid bacteria (LAB) of canineorigin from Salmonella-negative dogs’ faeces able to inhibit monophasic Salmonella Typhimurium previously isolated from dogs’ faeces, in order to be used as a potential probiotic in pet nutrition. Results: Accordingly, 37 LAB were isolated from Salmonella-negative dogs’ faeces and tested against monophasic S. Typhimurium using the spot on lawn method out of which 7 strains showed an inhibition halo higher than 2.5 cm. These 7 strains were also tested with the co-culture method and one showed the greatest inhibition value (p < 0.05). Subsequently, the isolate was identified through 16S rRNA sequencing and sequence homology and designated as Ligilactobacillus salivarius (L. salivarius). LAB from Salmonella-positive dogs were also identified and none was the selected strain. Finally, to identify the mechanism of inhibition of L. salivarius, the supernatant was analyzed, and a dose response effect was observed. Conclusions: It is concluded that the canine-origin L. salivarius, could possess some in vitro functional attributes of a candidate probiotic and could prevent monophasic S. Typhimurium colonization or inhibit its activity if the infection occurs.

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    UCH
    Phenotypic and genotypic antimicrobial resistance of "Listeria spp." in Spain2024-06

    Listeriosis is a zoonotic disease caused by Listeria monocytogenes and Listeria ivanovii. The genus Listeria currently includes 27 recognized species and is found throughout the environment. The number of systematic studies on antimicrobial resistance in L. monocytogenes isolates from domestic farms using antimicrobial substances is limited. Importantly, dairy ruminant farms are reservoir of hypervirulent lineage I L. monocytogenes isolates, previously associated with human clinical cases. Considering that the classes of antibiotics used in food-producing domestic animals are frequently the same or closely related to those used in human medicine, studies about the impact of antibiotic use on the acquisition of antibiotic resistance in Listeria spp. in domestic animal farms are, therefore, of high importance. Here, susceptibility to 25 antibiotics was determined. Eighty-one animal-related, 35 food and 21 human pathogenic Listeria spp. isolates and 114 animal-related non-pathogenic Listeria spp. isolates were tested. Whole genome sequencing data was used for molecular characterization. Regarding L. monocytogenes, 2 strains from the clinical-associated linage I showed resistance to erythromycin, both related to dairy ruminants. Acquired resistance to one antibiotic was exhibited in 1.5% of L. monocytogenes isolates compared with 14% of non-pathogenic Listeria spp. isolates. Resistance to tetracycline (7.9%), doxycycline (7.9%), penicillin (4.4%), and ampicillin (4.4%) were the most frequently observed in non-pathogenic Listeria spp. While resistance to two or more antibiotics (5.6%) was most common in Listeria spp., isolates, resistance to one antibiotic was also observed (1.6%). The present results show that non-pathogenic Listeria spp. harbour antimicrobial resistance genes.

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    UCH
    La trashumancia del ovino segureño : una oportunidad para la innovación docente en veterinaria2021-11-10

    La importancia de la producción de cordero en el Sureste, la existencia de un núcleo de trashumantes de ovino en la Sierra de Segura, y la consideración de la trashumancia como manifestación representativa del patrimonio cultural inmaterial nos ha llevado a explorar el potencial docente de la trashumancia con ovino segureño para estudiantes de veterinaria. Entre 2016 y 2019, cuatro profesores y dieciocho estudiantes de veterinaria de las Universidades de Murcia y Cardenal Herrera (UCH-CEU) de Valencia, hemos realizado diecinueve jornadas de trashumancia. Entre las acciones de innovación docente generadas destaca la exposición fotográfica “La Vereda de los Pontoneros” y el documental “Trashumancia, la Última Frontera”. Proponemos la integración de una semana de trashumancia en el periodo de las dos semanas de prácticas tuteladas con la Asociación Nacional de Criadores de Ovino Segureño (ANCOS), discutimos su integración en el grado de Veterinaria de Murcia y evidenciamos el interés docente de esta actividad inmersiva, que supera los propios contenidos del grado de veterinaria.

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    UCH
    Importance and antimicrobial resistance of "Mycoplasma bovis" in clinical respiratory disease in feedlot calves2021-05-20

    Bovine respiratory disease (BRD) is an important viral and/or bacterial disease that mainly affects feedlot calves. The involvement of Mycoplasma bovis in BRD can lead to chronic pneumonia poorly responsive to antimicrobial treatment. Caseonecrotic bronchopneumonia is a pulmonary lesion typically associated with M. bovis. In Spain, M. bovis is widely distributed in the feedlots and circulating isolates are resistant to most antimicrobials in vitro. However, the role of this species in clinical respiratory disease of feedlot calves remains unknown. Furthermore, available data are relative to a fixed panel of antimicrobials commonly used to treat BRD, but not to the specific set of antimicrobials that have been used for treating each animal. This study examined 23 feedlot calves raised in southeast Spain (2016–2019) with clinical signs of respiratory disease unresponsive to treatment. The presence of M. bovis was investigated through bacteriology (culture and subsequent PCR), histopathology and immunohistochemistry. The pathogen was found in 86.9% (20/23) of the calves, mainly in the lungs (78.26%; 18/23). Immunohistochemistry revealed M. bovis antigens in 73.9% (17/23) of the calves in which caseonecrotic bronchopneumonia was the most frequent lesion (16/17). Minimum inhibitory concentration assays confirmed the resistance of a selection of 12 isolates to most of the antimicrobials specifically used for treating the animals in vivo. These results stress the importance of M. bovis in the BRD affecting feedlot calves in Spain.

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    UCH
    Ruminant-associated "Listeria monocytogenes" isolates belong preferentially to dairy-associated hypervirulent clones : a longitudinal study in 19 farms2021-12-04

    Studies have shown that ruminants constitute reservoirs of Listeria monocytogenes, but little is known about the epidemiology and genetic diversity of this pathogen within farms. Here we conducted a largescale longitudinal study to monitor Listeria spp. in 19 dairy farms during three consecutive seasons (N = 3251 samples). L. innocua was the most prevalent species, followed by L. monocytogenes. Listeria monocytogenes was detected in 52.6% of farms and more frequently in cattle (4.1%) and sheep (4.5%) than in goat farms (0.2%). Lineage I accounted for 69% of L. monocytogenes isolates. Among animal samples, the most prevalent sublineages (SL) and clonal complexes (CC) were SL1/CC1, SL219/CC4, SL26/CC26 and SL87/CC87, whereas SL666/CC666 was most prevalent in environmental samples. Sixtyone different L. monocytogenes cgMLST types were found, 28% common to different animals and/or surfaces within the same farm and 21% previously reported elsewhere in the context of food and human surveillance. Listeria monocytogenes prevalence was not affected by farm hygiene but by season: higher prevalence was observed during winter in cattle, and during winter and spring in sheep farms. Cows in their second lactation had a higher probability of L. monocytogenes faecal shedding. This study highlights dairy farms as a reservoir for hypervirulent L. monocytogenes.

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    UCH
    Price fluctuation, protected geographical indications and employment in the Spanish small ruminant sector during the COVID-19 crisis2020-11-26

    O cial milk prices in the Spanish small ruminant sector were used for 5 years (2015–2019) to analyze the e ect caused by the coronavirus disease (COVID-19) crisis in 2020. Meat price fluctuations were also studied using the weekly prices o cially provided by some of the main agrarian markets of the country (n = 6) in 2019 and 2020. Moreover, the sales and prices of three protected geographical indications (PGI) of lamb meat served to study the marketability when the products are sold or not under these quality labels in a crisis context. According to Spanish Government’s o cial communications, 2020 was divided in three periods of study (pre-COVID-19, total confinement and post-confinement). The evolution of employment in this subsector in 2020, as a direct consequence of this crisis, was also analyzed considering data provided by producers. Results showed an intra-annual seasonal e ect for milk prices in 2020 for both livestock species, as observed in previous years. However, a negative economic impact on goat milk prices due to the pandemic was checked during the confinement and post-confinement months. Sheep milk prices remained stable. Lamb and goat kid meat prices showed a similar trend in comparison with 2019 during the pre-COVID-19 period. The total confinement period recorded a short interval of 1–2 weeks in which the prices declined, before the suspension of quotations in many markets. In contrast, once confinement was completed, meat prices for both ruminant species rapidly reached levels that existed before the coronavirus crisis. Overall data suggested the protective e ect of the PGI marks on lamb meat. Lambs with a PGI had better 2020 prices than non-PGI lambs (+8%), regardless of the period analyzed. Moreover, with fewer lambs sold in 2020, there was a relevant drop in sales of non-PGI lambs vs. PGI (􀀀19% vs. 􀀀2%) during the first 7 months. Finally, there was little or no readjustment of the workforce in the small ruminant flocks.