Effects of treatment with florfenicol in the control of bovine respiratory disease in feed-lots

El objetivo del presente ensayo fue evaluar la eficacia deltratamiento metafiláctico con dosis únicas de florfenicol (20 y40 mg/kg vía subcutánea) frente a la enfermedad respiratoriaen terneros en engorde a corral. Se incluyeron 1.297 terneros,machos y hembras, con peso promedio de 110 kg, divididosen 5 corrales. Los animales fueron asignados, al azar, en tresgrupos; florfenicol 20 mg/kg (FLO20), florfenicol 40 mg/kg (FLO40)mientras que el tercer grupo, control, no recibió tratamiento(CTL). Se registró el peso individual de cada uno de los gruposen estudio (n=30 por grupo) los días 0, 21 y 50 del ensayo.El diseño fue en bloque (corral) y el animal fue consideradola unidad experimental. El porcentaje de animales enfermosfue de 10,83; 3,48 y 2,31 para los grupos CTL, FLO20 y FLO40,respectivamente. Además, se observó en los primeros 21 díasdel ensayo, una mayor ganancia diaria de peso (p<0,001) enlos grupos FLO20 y FLO40. El tratamiento metafiláctico con FLOdisminuyó la morbilidad por enfermedad respiratoria y mejoróla ganancia diaria de peso. No se encontraron diferenciasestadísticamente significativas entre los grupos FLO20 y FLO40en la ganancia diaria, incidencia de enfermedad respiratoria,porcentaje de retratamientos, ni mortalidadThe aim of this study was to evaluate the efficacy of metaphylactic treatment with single doses of florfenicol (20 and 40 mg/kg subcutaneously), against respiratory disease in feedlot calves. A total of 1297 male and female calves with an average weight of 110 kg were placed in five pens. They were randomly assigned to three groups: one group treated with florfenicol SC 20mg/kg (FLO20), a group treated with florfenicol SC 40 mg/kg (FLO40) and the control group (CTL) received no treatment. Individual weight was obtained in each group (n=30) on days 0, 21 and 50 of the trial. A complete randomize block (pen) design was used and the animal was considered the experimental unit. The percentage of ill animals was 10.83, 3.48 and 2.33 for the CTL, FLO20 and FLO40 groups, respectively. Moreover, a higher daily weight gain was observed in the FLO20 and FLO40 groups within the first 21 days of the trial (p<0,001). Metaphylactic treatment with FLO reduced morbidity due to respiratory disease and improved daily weight gain. No statistically significant differences were found between FLO20 and FLO40 groups regarding daily weight gain, respiratory bovine disease incidence, retreatment or mortality.Fil: Galvan, Walter Ruben. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Arriaga, Guido José. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Streitenberger, Nicolás. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Landoni, Maria Fabiana. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Fazzio, Luis Emilio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin

Un tratamiento metafiláctico con doble dosis de oxitetraciclina reduce el riesgo de enfermedad respiratoria bovina en terneros de engorde a corral

El objetivo del presente estudio fue evaluar el efecto del tratamiento metafiláctico con oxitetraciclina (OTC), a simple y doble dosis, en bovinos con alto riesgo de padecer enfermedad respiratoria bovina (ERB). El estudio se realizó en un establecimiento de engorde a corral donde se utilizaron 2.754 terneros que fueron considerados de alto riesgo de padecer ERB. Se utilizó un diseño en bloque completamente al azar donde se consideró al animal como la unidad experimental y el corral (n=10) como bloque. Se formaron tres grupos experimentales: 1- control (CTL) el cual permaneció sin tratamiento, 2- recibió OTC 20 mg/kg SC (OTC20) y 3- recibió OTC 40 mg/kg SC (OTC40). El riesgo de ERB fue evaluado a través de una regresión logística. Los animales del grupo CTL tuvieron 2,85 y 7,14 veces más chances de enfermarse de ERB que los animales de los grupos OTC20 y OTC40 respectivamente (p<0,001). En conclusión, el tratamiento metafiláctico con OTC es útil para reducir el riesgo de padecer ERB en engorde a corral, siendo su efecto mayor cuando se aplica a la dosis de 40 mg/kg.The objective of this study was to evaluate the effect of a metaphylactic treatment with oxytetracycline (OTC) in the labeled and double doses on the risk for bovine respiratory disease (BRD) in feedlot calves. This study was conducted in a commercial feedlot where 2,754 calves belonging to high risk groups were enrolled. A randomized complete block design was used, with animals as experimental units and pens (n=10) as blocks. Three experimental groups were assessed: 1- untreated control (CTL), 2- OTC 20 mg/kg SC (OTC20) and 3- OTC 40 mg/kg SC (OTC40). The risk for BRD was evaluated with a mixed logistic regression. Untreated CTL had 2.85 and 7.14 more chances of getting BRD than OTC20 and OTC40 groups, respectively (p<0.001). In conclusion, metaphylactic treatment with OTC is useful to reduce the risk for BRD in feedlot cattle, being protective effect higher at double dose than at labeled one.Fil: Fazzio, Luis Emilio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Giuliodori, Mauricio Javier. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Galvan, Walter Ruben. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Streitenberger, Nicolás. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Landoni, Maria Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin

The effect of anthelmintic resistance on the productivity in feedlot cattle

The aim of this study was to evaluate, in a commercial feedlot, the effect of different anthelmintic drugs on the productivity of naturally infected calves from a cow-calf operation, where resistance to ivermectin (IVM) has been previously detected. The study began with the random selection of 80 calves whose weight was 132 ± 12. kg. Four groups were made: IVM, ricobendazole (RBZ), ricobendazole plus levamisol (RBZ + LEV) and a control group (CG) without treatment. On days 0, 21, 42, 70, 98 and 126, manual collection of fecal matter and individual weight were registered. Mixed SAS procedure was used for statistical analysis. The percentages of fecal egg count reduction test (FECRT) calculated 21days post treatment (PT) were 18%, 96% and 100% for the IVM, RBZ and RBZ + LEV groups, respectively. Body weight (± SEM) at the end of the trial was 266. kg (±0.9), 269. kg (±1.1), 276. kg (±1.3), 280. kg (±1.9) for CG, IVM, RBZ and RBZ + LEV groups, respectively. The effect on live weight was highly significant (p < 0001). After 126 days of fattening, the deleterious effect of the combination of Cooperia and Haemonchus in the IVM group on body weight was evident. Undetected animals carrying anthelmintic resistant (AR) worms entering the feedlot, could cause major productivity losses.Fil: Fazzio, Luis Emilio. Facultad de Ciencias Veterinarias, Universidad Nacional de la Plata; ArgentinaFil: Sánchez, Ricardo O.. Laboratorio Mesopotámico de Diagnóstico Veterinario; ArgentinaFil: Streitenberger, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Facultad de Ciencias Veterinarias, Universidad Nacional de la Plata; ArgentinaFil: Galvan, Walter Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Facultad de Ciencias Veterinarias, Universidad Nacional de la Plata; ArgentinaFil: Giudici, Claudio J.. Universidad Nacional de Rosario; ArgentinaFil: Gimeno, Eduardo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Facultad de Ciencias Veterinarias, Universidad Nacional de la Plata; Argentin

Ivermectin 1% efficacy by different routes and doses against resistant nematodes in cattle

La resitencia antielmintica (RA) a ivermectina (IVM) y otras lactonas macrocíclicas(LM) es un fenómeno mundialmente conocido . En ovinos, la administración de LMpor vía oral o intra-ruminal y en alta dosis ha logrado mejorar la eficacia frente aparásitos gastrointestinales (PGI), sin embargo no abundan aún experienciassimilares bovinos. El objetivo del presente ensayo fue evaluar la eficacia de IVM aalta dosis y por diferentes vías en terneros portadores de PGI resistentes a IVM enun engorde a corral comercial. De un total de 125 se seleccionaron 44 ternerosmachos, clínicamente sanos, los cuales fueron asignados a 4 grupos (n=11animales/grupo) que recibieron IVM a dosis estándar (0,2 mg/kg) y alta (1 mg/kg) ypor vía subcutánea e intra-ruminal. Previo al día del tratamiento (día ? 6) setomaron muestras de materia fecal para recuento de huevos de PGI por gramo ycoprocultivo; además se registró el peso individual de cada animal. El día deltratamiento fue considerado el día 0. En los días +14 y +27 se tomaron muestrasde materia fecal mientras que en el día +27 se registró nuevamente el peso. Lareducción en el recuento de huevos en materia fecal en el día +14 y +27 no mostró diferencias entre los grupos, dejando en evidencia la falta de eficacia de la droga aún en dosis quíntuple. No se observó diferencias en la ganancia diaria de peso entre los grupos. En el presente ensayo el uso de IVM en los diferentes grupos aalta dosis y por diferentes vías no obtuvo mejoras en los porcentajes de reducciónde huevos en materia fecal en bovinos portadores de PGI resistentes.Anthelmintic resistance to ivermectin and macrocyclic lactones (ML) is a worldwide spread problem. A high dose schedule of ML was effective against resistant nematodes in sheep, given oral and intra-ruminal. However, no enough data are available from cattle on this issue. Thus, the goal of this work was the efficacy assessment of IVM given at different doses and routes. To achieve this goal, 44 male feedlot calves, infected with IVM resistant nematodes, were assigned to four groups (n=11 calves per group). They received standard (0.2 mg/kg), or high doses (1 mg/kg) of IVM by subcutaneous or intra-ruminal routes. Before treatment (day -6), feces were sampled for eggs per gram counts (EPG) and copocultures; weight was also measured on this date. The treatments were administered on day 0. Later, on days +14 and +27, feces were re-sampled, and calves were weighed again just in the last date. Fecal egg count reductions showed no statistical differences between groups. This evidenced the lack of efficacy for IVM, even at a fivefold dose. Weight was neither different between groups. In conclusion, higher doses of IVM given by subcutaneous or intra-ruminal routes were insufficient to kill IVM-resistant nematodes in calves.Fil: Galvan, Walter Ruben. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Fazzio, Luis Emilio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Streitenberger, Nicolás. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Galarza, E.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Lizarraga, R.. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Sánchez, Ricardo. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Sanabria, Rodrigo Eduardo Fabrizio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentin

Efficacy and productive performance of moxidectin in feedlot calves infected with nematodes resistant to ivermectin

Anthelmintic resistance (AR) of gastrointestinal nematodes to macrocyclic lactones is an increasingly common worldwide phenomenon limiting cattle production. This has motivated the search for alternatives, such as new active compounds, added drug synergisms, different doses, and alternate administration routes. The aim of this study was the assessment of moxidectin (MXD) performance in feedlot calves with a history of AR to ivermectin (IVM). Crossbred female calves aged 6-7 months and weighing 163 kg (SD = 34 kg) were divided into 3 groups of 35 animals each. They were assigned to the following antiparasitic treatment groups: IVM group (0.2 mg/kg IVM); MXD group (0.2 mg/kg MXD), and ricobendazole + levamisole (RBZ + LEV) group (7.5 mg/kg RBZ + 8 mg/kg LEV). On days 0, 26, and 47, fecal samples were taken and the weight of each animal was registered. Anthelmintic efficacy (by fecal egg count reduction), total weight gain (TWG) and average daily weight gain (AWG) were compared between the groups. A mixed SAS procedure was used for statistical analysis. Fecal egg count reduction 26 days post-treatment (PT) was calculated at 28% for the IVM group, 85% for the MXD group, and 99% for the RBZ + LEV group. AWGs (Standard Error) of 1.095 g (56), 1.264 g (49), and 1.340 g (52) were registered for the IVM, MXD, and RBZ + LEV groups, respectively (p < 0.05). Coprocultures revealed that MXD more effectively reduced Haemonchus spp. and Cooperia spp. egg counts than IVM. This resulted in higher AWGs and TWGs for this group; similar results were seen for the RBZ + LEV group as well. In this study, animals treated with MXD gained about 160 more g/day than animals treated with IVM. This represents a gain of 16 USD per animal over the 47 day trial.Fil: Fazzio, Luis Emilio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Streitenberger, Nicolás. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Galvan, Walter Ruben. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Sánchez, R. O.. Laboratorio Mesopotámico de Diagnóstico Veterinario; ArgentinaFil: Gimeno, Eduardo Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Sanabria, Rodrigo Eduardo Fabrizio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; Argentin

Pharmacokinetic profile and anthelmintic efficacy of moxidectin administered by different doses and routes to feedlot calves

We evaluated the comparative plasma disposition kinetics and efficacy of moxidectin (MXD), administered by the intraruminal (IR) or subcutaneous (SC) route at two different dosage levels (0.2 and 1 mg/kg) in feedlot calves. Additionally, the efficacy was compared to an ivermectin (IVM, SC administration) treated group. This study was divided into two separate studies, the ?Pharmacokinetic (PK) study? and the ?Efficacy study?. The ?PK study? involved 24 calves free of gastrointestinal nematodes (GIN), which were allocated into 4 groups (n = 6) and treated with MXD by either the SC or the IR route at the therapeutic (MXDSC0.2, MXDIR0.2, respectively) or at fivefold the therapeutic dose (MXDSC1.0, MXDIR1.0, respectively). Blood samples were collected from 3 h up to 14 days post-treatment. MXD concentrations in plasma samples were analyzed by HPLC. The ?Efficacy study? included 125 calves naturally infected with GIN, which were allocated into five experimental groups (n = 25 each); the same four MXD-treated groups described for the ?PK study?, and an additional group treated by the SC route with IVM (IVMSC0.2). The efficacy of IVM given at its therapeutic dose and the different MXD groups at the therapeutic and fivefold the therapeutic dose was calculated by analysis of the individual efficacy using the package eggCounts-2.1-1´ on the R software environment, version 3.5.0 (R Core Team, 2018). Daily weight gain (DWG) was also measured over the first 47 days of the fattening cycle. Independently of the administration route, MXD peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) were higher in groups treated with the higher dose (1.0 mg/kg), whereas a longer time to reach Cmax (Tmax) was observed after the IR treatments. The observed MXD efficacies were 85% (MXDSC0.2), 94% (MXDSC1.0), 84% (MXDIR0.2) and 99% (MXDIR1.0), at day +27. At day +27, all MXD-treated groups showed higher efficacies than the group having received IVM (45%). The post-treatment Cooperia spp. L3 counts were particularly low in the groups MXDSC1.0 and MXDIR1.0. All of the groups treated with MXD showed better DWG than the IVMSC0.2 group (P = 0.01). Dose and administration route modifications effectively improved the anthelmintic and productive performance of MXD. A high dose of MXD improved the control of IVM-resistant GIN in feedlot calves. However, this practice must be taken with caution, since MXD resistance could rapidly emerge, especially in grazing cattle.Fil: Fazzio, Luis Emilio. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Moreno Torrejon, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatología. Laboratorio de Farmacología; ArgentinaFil: Galvan, Walter Ruben. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Cantón, Candela. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatología. Laboratorio de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; ArgentinaFil: Alvarez, Luis Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatología. Laboratorio de Farmacología; ArgentinaFil: Streitenberger, Nicolás. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Sánchez Ricardo Oscar. Laboratorio Mesopotámico; ArgentinaFil: Lanusse, Carlos Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigación Veterinaria de Tandil. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigación Veterinaria de Tandil. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Centro de Investigación Veterinaria de Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatología. Laboratorio de Farmacología; ArgentinaFil: Sanabria, Rodrigo Eduardo Fabrizio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentin

Measurement of the production cross section of prompt Ξ0c baryons in p–Pb collisions at √sNN = 5.02 TeV

The transverse momentum (pT) differential production cross section of the promptly-produced charm-strange baryon Ξ0c (and its charge conjugate Ξ0c¯¯¯¯¯¯) is measured at midrapidity via its hadronic decay into π+Ξ− in p−Pb collisions at a centre-of-mass energy per nucleon−nucleon collision sNN−−−√ = 5.02 TeV with the ALICE detector at the LHC. The Ξ0c nuclear modification factor (RpPb), calculated from the cross sections in pp and p−Pb collisions, is presented and compared with the RpPb of Λ+c baryons. The ratios between the pT-differential production cross section of Ξ0c baryons and those of D0 mesons and Λ+c baryons are also reported and compared with results at forward and backward rapidity from the LHCb Collaboration. The measurements of the production cross section of prompt Ξ0c baryons are compared with a model based on perturbative QCD calculations of charm-quark production cross sections, which includes only cold nuclear matter effects in p−Pb collisions, and underestimates the measurement by a factor of about 50. This discrepancy is reduced when the data is compared with a model in which hadronisation is implemented via quark coalescence. The pT-integrated cross section of prompt Ξ0c-baryon production at midrapidity extrapolated down to pT = 0 is also reported. These measurements offer insights and constraints for theoretical calculations of the hadronisation process. Additionally, they provide inputs for the calculation of the charm production cross section in p−Pb collisions at midrapidity

Measurement of Ω0c baryon production and branching-fraction ratio BR(Ω0c → Ω−e+νe)/BR(Ω0c → Ω−π+) in pp collisions at √s = 13 TeV

The inclusive production of the charm-strange baryon Ω0c is measured for the first time via its semileptonic decay into Ω−e+νe at midrapidity (|y| < 0.8) in proton–proton (pp) collisions at the centre-of-mass energy √s = 13 TeV with the ALICE detector at the LHC. The transverse momentum (pT) differential cross section multiplied by the branching ratio is presented in the interval 2 < pT < 12 GeV/c. The branching-fraction ratio BR(Ω0c → Ω−e+νe)/BR(Ω0c → Ω−π+) is measured to be 1.12 ± 0.22 (stat.) ± 0.27 (syst.). Comparisons with other experimental measurements, as well as with theoretical calculations, are presented

Measurement of Ωc0\Omega^0_{\rm c} baryon production and branching-fraction ratio BR(Ωc0→Ω−e+νe)/BR(Ωc0→Ω−π+){\rm BR(\Omega^0_c \rightarrow \Omega^- e^+\nu_e)} / {\rm BR(\Omega^0_c \rightarrow \Omega^- \pi^+)} in pp collisions at s\sqrt{s} = 13 TeV

International audienceThe inclusive production of the charm-strange baryon $\Omega^{0}_{\rm c}$ is measured for the first time via its semileptonic decay into $\Omega^{-}\rm e^{+}\nu_{e}$ at midrapidity ($|y|<0.8$) in proton$-$proton (pp) collisions at the centre-of-mass energy $\sqrt{s}=13$ TeV with the ALICE detector at the LHC. The transverse momentum ($p_{\rm T}$) differential cross section multiplied by the branching ratio is presented in the interval $2<p_{\rm T}<12~{\rm GeV}/c$. The branching-fraction ratio ${\rm BR}(\Omega^0_{\rm c} \rightarrow \Omega^{-}{\rm e}^{+}\nu_{\rm e})/ {\rm BR}(\Omega^0_{\rm c} \rightarrow \Omega^{-}{\pi}^{+})$ is measured to be 1.12 $\pm$ 0.22 (stat.) $\pm$ 0.27 (syst.). Comparisons with other experimental measurements, as well as with theoretical calculations, are presented

Measurement of Ωc0\Omega^0_{\rm c} baryon production and branching-fraction ratio BR(Ωc0→Ω−e+νe)/BR(Ωc0→Ω−π+){\rm BR(\Omega^0_c \rightarrow \Omega^- e^+\nu_e)} / {\rm BR(\Omega^0_c \rightarrow \Omega^- \pi^+)} in pp collisions at s\sqrt{s} = 13 TeV

International audienceThe inclusive production of the charm-strange baryon $\Omega^{0}_{\rm c}$ is measured for the first time via its semileptonic decay into $\Omega^{-}\rm e^{+}\nu_{e}$ at midrapidity ($|y|<0.8$) in proton$-$proton (pp) collisions at the centre-of-mass energy $\sqrt{s}=13$ TeV with the ALICE detector at the LHC. The transverse momentum ($p_{\rm T}$) differential cross section multiplied by the branching ratio is presented in the interval $2<p_{\rm T}<12~{\rm GeV}/c$. The branching-fraction ratio ${\rm BR}(\Omega^0_{\rm c} \rightarrow \Omega^{-}{\rm e}^{+}\nu_{\rm e})/ {\rm BR}(\Omega^0_{\rm c} \rightarrow \Omega^{-}{\pi}^{+})$ is measured to be 1.12 $\pm$ 0.22 (stat.) $\pm$ 0.27 (syst.). Comparisons with other experimental measurements, as well as with theoretical calculations, are presented