Factors associated with suicide risk and attempts in healthcare students: A cross-sectional study. / Factores asociados al riesgo e intentos suicidas en estudiantes de carreras de la salud: estudio transversal.

Introduction: Suicide deaths in young people have been increasing in recent decades and are considered a major public health problem worldwide, being a partially preventable event. The prevalence of suicidal ideation is high among university students, especially in health careers. The objective of this study was to measure the prevalence of high suicidal risk in this specific group and to identify associated factors, aiming to provide empirical evidence for the construction of effective suicide prevention strategies. Methods: A cross-sectional study was conducted based on an online survey directed to healthcare students near the end of the first year of the COVID-19 pandemic to learn about the frequency of suicidal risk and its associated factors. The sample consisted of 477 students (70.8% female, mean age 21.7 ± 2.5 years) from eight healthcare majors. The data were collected in January 2021. Results: 22.6% of the young people reported a high suicide risk on the Okasha scale, and 3.4% made a suicide attempt in the previous year. Factors associated with high suicidal risk were having a non-heterosexual orientation, an irregular academic trajectory, experiences of physical and/or psychological violence, higher levels of depressive and anxious symptomatology, as well as lower levels of social support from friends and family. Conclusions: Suicide risk and attempt levels are high in this group of students, and there is a group of factors that could guide more effective actions, such as support for higher-risk groups and screening to identify and provide support to young people at high suicidal risk and with mental health conditions.

Introducción: Las muertes por suicidio en jóvenes han ido en aumento en las últimas décadas y se considera un problema de salud pública prioritario a nivel mundial, siendo un evento parcialmente prevenible. La prevalencia de ideas suicidas es alta entre estudiantes universitarios, especialmente en carreras de la salud. El objetivo de este estudio fue medir la prevalencia de alto riesgo suicida en este grupo específico e identificar factores asociados, con la finalidad de aportar evidencia empírica para la construcción de estrategias efectivas de prevención del suicidio. Métodos: Se realizó un estudio transversal basado en una encuesta en línea a estudiantes de carreras de la salud, casi al final del primer año de la pandemia de COVID-19, para conocer la frecuencia del riesgo suicida y sus factores asociados. La muestra fue de 477 estudiantes (70,8% mujeres, edad promedio 21,7 ± 2,5 años), de ocho carreras de la salud. Los datos se recogieron en enero de 2021. Resultados: Un 22,6% de los jóvenes reportó un alto riesgo suicida en la escala de Okasha y 3,4% hizo un intento suicida en el año previo. Los factores asociados al alto riesgo suicida fueron: tener una orientación no-heterosexual, una trayectoria académica irregular, experiencias de violencia física y/o psicológica, mayores niveles de sintomatología depresiva y ansiosa, así como menores niveles de apoyo social de amigos y de la familia. Conclusiones: Las cifras de riesgo e intentos suicidas son elevadas en este grupo de estudiantes y existe un perfil de factores que podrían orientar acciones más efectivas, tales como apoyo a grupos de mayor riesgo y hacer tamizaje para identificar y dar ayuda a jóvenes con alto riesgo suicida y con problemas de salud mental.

Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae and risk factors associated with high total bacterial count in bulk tank milk from dairy farms in Colombia.

The objective of the study was to evaluate the frequency and genetic characteristics of ESBL-producing Escherichia coli and Klebsiella spp. and the risk factors associated with a high total bacterial count in bulk tank milk samples of dairy farms in three municipalities of the Antioquia Department, Colombia. Fifteen samples were positive for E. coli and Klebsiella spp. Subsequent analysis of the 16 S rRNA gene sequences confirmed these isolates included E. coli (n = 3), K. oxytoca (n = 11), and K. pneumoniae (n = 1). None of the isolates was positive for ESBL identification by phenotypic methods, but the only the isolate of K. pneumoniae was positive for the blaSHV61 gene by sequence analysis. The antibiotic susceptibility evaluation for all Klebsiella spp. isolates identified resistance to fosfomycin (50%; 6/12) and ampicillin (100%; 12/12). While most of the herds maintain adequate hygienic quality, specific risk factors such as having more than 60 milking cows, frequent changes in milkers, milking in paddocks, and using a chlorinated product for pre-dipping have been identified as associated with a high total bacterial count > 100,000 CFU/mL in bulk tank milk. However, certain variables including the milker being the owner of the animals and the proper washing and disinfection of the milking machine contribute to maintain a high level of hygiene and quality in the raw milk stored in the tanks. In conclusion, the frequency of ESBL producers was relatively low, with only K. pneumoniae testing positive for the blaSHV ESBL type. The presence of these bacteria in milk tanks represents a potential risk to public health for consumers of raw milk and its derivatives.

Staphylococcus aureus, Escherichia coli, and Klebsiella spp. prevalence in bulk tank milk of Colombian herds and associated milking practices.

Background and Aim: Bovine mastitis is one of the most costly and prevalent diseases in dairy herds, which can be prevented and controlled through proper milking practices, diagnosis, and elimination of chronic animals, among others. Contagious pathogens such as Staphylococcus aureus and environmental pathogens such as Escherichia coli and Klebsiella spp. can affect cows and milk for human consumption, generating a public health risk. This study aimed to estimate the prevalence of herds with somatic cell count (SCC) ≥200,000 cells/mL, S. aureus, E. coli, and Klebsiella spp., in bulk tank milk (BTM) and its associated risk factors in Colombian dairy cow herds. Materials and Methods: A cross-sectional probabilistic study was carried out in 150 dairy herds located in the north of the Antioquia province. A single visit per herd was conducted, during which three BTM samples were aseptically collected. General data and milking practices were collected through an epidemiological survey applied in each herd. Results: The prevalence of S. aureus, E. coli, and Klebsiella spp. were 14% (21/150), 2% (3/150), and 8% (12/150), respectively. Moreover, 95% of the herds presented an SCC of ≥200,000 cells/mL. Practices such as in-paddock milking, change of milker during the last month, use of disposable gloves, and hand disinfection were associated with increased prevalence of S. aureus, whereas proper dipping was a protective factor. Proper washing and disinfection of the milking machine, use of chlorinated disinfectants for hand hygiene, and use of disposable gloves decreased the prevalence of E. coli and Klebsiella spp. Bulk tank SCC increased in herds with 30-60 milking cows, herds with >60 milking cows, and herds with a change of milker during the last month. Hand disinfection and dipping decreased the SCC. Conclusion: Staphylococcus aureus, E. coli, and Klebsiella spp. were prevalent in BTM from dairy cow herds. The risk of S. aureus isolation was higher in herds with an in-paddock milking system. The risk of E. coli and Klebsiella spp. isolation were higher in herds with >60 milking cows, with a change of milker during the last month. Processes such as avoiding changing the milker and greater control in medium and large herds could improve the SCC in BTM.

Paratuberculosis control strategies in dairy cattle: A systematic review.

Background: Mycobacterium avium subsp. paratuberculosis is the causative agent of paratuberculosis (PTB), incurable enterocolitis, affecting domestic and wild ruminants. Economic losses, impacts on animal health and welfare, and public health concerns justify its herd-level control. Aim: To systematically collect information to answer: What are the control and eradication strategies of PTB in dairy cattle worldwide? Methods: The search procedure was carried out on October 2nd, 2019, and updated on August 3rd, 2021, using OVID®, SciELO, and Redalyc databases, and the registers from the International Colloquium on Paratuberculosis (1991-2018). The inclusion criteria considered articles published in English, Portuguese, and Spanish and in peer-reviewed journals. The exclusion criteria included irrelevant topics, species other-than bovines, and not original articles. Definitive studies were obtained through the consensus of the authors on eligibility and quality. Data extraction was performed, considering bibliographic information, control and outcome strategies, follow-up time, and results. Results: Twenty-six relevant studies were found, reporting the use of three grouped control strategies: hygiene and management strategy (HMS), test-and-cull strategy (TCS), and vaccination strategy (VS). The HMS was the most common one (20/26), followed by TCS (17/26) and VS (7/26). Combined control strategies such as TCS-HMS (12/26), TCS-VS (1/26), and HMS-VS (1/26) were also described, and the consideration of the three control strategies (TCS-HMS-VS) was reported in two articles. The HMS included practices such as neonates/juvenile livestock hygiene, biosecurity, prevention of infection introduction into the herd, and environmental management. Within HMS, the most frequent practices were to remove calves from their dams as soon as possible after birth and to keep the minimal exposure of calves and heifers to adult cattle. As limitations, within the HMS, it is considered that some strategies cannot be included due to lack of compliance, or the application of the same strategy among one study and another may have a different degree of interpretation; publication bias was not controlled since the results of the control programs in endemic countries may be not available. Conclusion: The main PTB control strategies in dairy cattle worldwide are HMS, TCS, and VS. The use of one or several combined strategies has been found to succeed in controlling the disease at the herd-level.

Study of Volatile Organic Compounds of Two Table Grapes (cv. Italia and Bronx Seedless) along Ripening in Vines Established in the Aegean Region (Turkey).

(1) Background: Italia is a seeded grape variety widely cultivated in the Aegean Region in Turkey, whereas Bronx Seedless is a seedless grape variety, preferred by consumers due to its pink berries and interesting flavor. The goal was to study the volatile compounds of these table grapes throughout berry ripeness. (2) Methods: The volatile compounds were analyzed by GC-MS in six different phenological stages (3) Results: Bronx Seedless grapes presented a higher content of seven terpenes, three aldehydes, one fatty acid, three alcohols, one C6 compound, total aldehydes and total alcohols, and a lower content of eleven terpenes, one fatty acid, four esters, one alcohol, four C6 compounds and its total content than Italia table grapes. The concentration of most of the volatile compounds analyzed increased from "begin of berry touch" to "berries ripe for harvest" stages. Terpenes content in both varieties at harvest was lower than 1.0 mg L-1. ß-ionone presented the highest odor activity value (OAV) in both varieties. Bronx Seedless grapes presented higher OAV for (Z)-3-hexenal and cedrol, and lower hexanal to (E)-2-hexenal ratio than Italia grapes. (4) Conclusions: Both varieties could be classified as neutral aromatical varieties and it is probable that to achieve a better aromatic quality, Bronx Seedless should be harvested later than Italia.

Adapting Grapevine Productivity and Fitness to Water Deficit by Means of Naturalized Rootstocks.

Climate change effects are unbalanced in all regions and cultivars linked to the wine industry. However, the impact of extreme weather events, such as drought and rising global temperatures, highlight the potential vulnerability in plant productivity, phenology, and crop water requirements that affect quality and harvests. Among adaptative measures for grapevine cultivars in existing or new winegrowing areas, the use of tolerant rootstocks to abiotic stress has been regarded as a mid-term strategy to face emerging constrains. The aim of this study was to compare naturalized or autochthonous rootstocks influence over grapevine cultivar performance and to characterize their response to deficit irrigation conditions. Data was collected from Cabernet Sauvignon and Syrah grafted plants for over 3 growing seasons (2018-2021) from a hyper-arid experimental field in Vicuña, Chile. Morpho-physiological parameters were determined throughout seasons and combinations where significant effects from rootstocks, irrigation treatment, and cultivar were observed over An and gs, thus modifying CO2 assimilation and intrinsic Water Use Efficiency (WUEi). Primary productivity and yield were also modified by rootstock depending upon cultivar hydric behavior. Interestingly, cluster and berry traits were unaffected despite how water productivity and integral water stress were modulated by rootstock. In both cultivars, it was observed that trait responses varied according to the irrigation conditions, rootstocks, and their respective interactions, thus highlighting a relative influence of the rootstocks in the processes of adaptation to the water deficit. Moreover, harvest date and acidity were modified by deficit irrigation treatment, and rootstocks did not modify phenological stages. Adaptation of grapevines to expected lower water availability might be improved by using suitable tolerant rootstocks, and maturity index can be modified through irrigation management.

Protocol for controlled cortical impact in human cerebral organoids to model traumatic brain injury.

Modeling traumatic brain injury (TBI) has been a challenge. Rodent and cellular models have provided relevant contributions despite their limitations. Here, we present a protocol for a TBI model based on the controlled cortical impact (CCI) performed on human cerebral organoids (COs), self-assembled 3D cultures that recapitulate features of the human brain. Here, we generate COs from iPSCs obtained from reprogrammed fibroblasts. For complete details on the use and execution of this protocol, please refer to Ramirez et al. (2021).

Modeling Traumatic Brain Injury in Human Cerebral Organoids.

Traumatic brain injury (TBI) is a head injury that disrupts the normal brain structure and function. TBI has been extensively studied using various in vitro and in vivo models. Most of the studies have been done with rodent models, which may respond differently to TBI than human nerve cells. Taking advantage of the recent development of cerebral organoids (COs) derived from human induced pluripotent stem cells (iPSCs), which resemble the architecture of specific human brain regions, here, we adapted the controlled cortical impact (CCI) model to induce TBI in human COs as a novel in vitro platform. To adapt the CCI procedure into COs, we have developed a phantom brain matrix, matching the mechanical characteristics of the brain, altogether with an empty mouse skull as a platform to allow the use of the stereotactic CCI equipment on COs. After the CCI procedure, COs were histologically prepared to evaluate neurons and astrocyte populations using the microtubule-associated protein 2 (MAP2) and the glial fibrillary acidic protein (GFAP). Moreover, a marker of metabolic response, the neuron-specific enolase (NSE), and cellular death using cleaved caspase 3 were also analyzed. Our results show that human COs recapitulate the primary pathological changes of TBI, including metabolic alterations related to neuronal damage, neuronal loss, and astrogliosis. This novel approach using human COs to model TBI in vitro holds great potential and opens new alternatives for understanding brain abnormalities produced by TBI, and for the development and testing of new therapeutic approaches.

Equine-Like H3 Avian Influenza Viruses in Wild Birds, Chile.

Since their discovery in the United States in 1963, outbreaks of infection with equine influenza virus (H3N8) have been associated with serious respiratory disease in horses worldwide. Genomic analysis suggests that equine H3 viruses are of an avian lineage, likely originating in wild birds. Equine-like internal genes have been identified in avian influenza viruses isolated from wild birds in the Southern Cone of South America. However, an equine-like H3 hemagglutinin has not been identified. We isolated 6 distinct H3 viruses from wild birds in Chile that have hemagglutinin, nucleoprotein, nonstructural protein 1, and polymerase acidic genes with high nucleotide homology to the 1963 H3N8 equine influenza virus lineage. Despite the nucleotide similarity, viruses from Chile were antigenically more closely related to avian viruses and transmitted effectively in chickens, suggesting adaptation to the avian host. These studies provide the initial demonstration that equine-like H3 hemagglutinin continues to circulate in a wild bird reservoir.

An overview about the impacts of agricultural practices on grape nitrogen composition: Current research approaches.

Nitrogen is a structural component of proteins, nucleic acids, chlorophyll, hormones and amino acids. The last one and ammonium are important primary metabolites in grapes and are key compounds in winemaking since they are primary sources for yeast fermentation. Currently, grape quality has been affected due to the negative impacts of global warming and anthropogenic activity. Certain studies have reported a significant decrease in the free amino acids content and an increase in berry soluble solids and in proline biosynthesis in grapes in some grapevine varieties cultivated under warm climate conditions and water restriction. Proline is not metabolized by yeasts and stuck and sluggish fermentations can occur when the content of yeast assimilable nitrogen is low. Nitrogen composition of grape is mainly affected by variety, edaphoclimatic conditions of the vineyard and agricultural practices performed to the grapevines. This review summarized the most current research carried out to modify the nitrogen composition of the grape and give an overview of the technical and scientific aspects that should be considered for future research in this field.

Risk factors and spatial relative risk assessment for influenza A virus in poultry and swine in backyard production systems of central Chile.

Backyard production systems (BPS) are a common form of poultry and swine production worldwide. The limited implementation of biosecurity standards in these operations makes BPS a potential source for the emergence of pathogens that have an impact on both animal and public health. Information regarding circulation of influenza A virus (IAV) in poultry and swine raised in BPS is scarce; particularly in South American countries. The objective of this study was to estimate prevalence and seroprevalence of IAV in BPS in central Chile, identify subtype diversity, evaluate risk factors and spatial relative risk for IAV. Samples were collected from 329 BPS from central Chile. Seroprevalence at BPS level was 34.7% (95% CI: 23.1%-46.2%), 19.7% (95% CI: 9.9%-30.6%) and 11.7% (95% CI: 7.2%-16.4%), whereas prevalence at BPS level was 4.2% (95% CI: 0.0%-8.8%), 8.2% (95% CI: 0.8%-14.0%) and 9.2% (95% CI: 4.8%-13.1%), for the Metropolitan, Valparaiso and LGB O'Higgins regions, respectively. Spatial analysis revealed that central-western area of Metropolitan region and the southern province of Valparaiso region could be considered as high-risk areas for IAV (spatial relative risk = 2.2, p < .05). Logistic regression models identified the practice of breeding both poultry and pigs at the BPS as a risk factor (95% CI 1.06-3.75). From 75 IAV ELISA-positive sera, 20 chicken sera had haemagglutination inhibition titres ranging from 20 to 160, and of these, 11 had microneutralization titres ranging from 40 to 960 for one or more IAV subtypes. Identified subtypes were H1, H3, H4, H9, H10 and H12. Results from this study highlight the need for further IAV surveillance programmes in BPS in Chile. Early detection of IAV strains circulating in backyard animals, especially in regions with large human populations, could have an enormous impact on animal and public health.

L-carnitine supplementation descreases hepatic triglyceride accumulation in Holstein cows during the transition period / La suplementación con L-carnitina disminuye la acumulación de triglicéridos hepáticos en vacas Holstein durante el periodo de transición / Suplementação com L-carnitina diminui o acúmulo de triglicerídeos hepáticos em vacas Holandesas durante o período de transição

Abstract Background: The increased use of body reserves observed during peripartum leads to higher needs of L-carnitine by cows, which is restrictive under the production conditions of Colombian high tropics. Objective: To evaluate the lipotropic potential of L-carnitine in Holstein dairy cows during the transition period to lactation. Methods: Twenty-one Holstein cows were fed 0, 100, or 200 g/d L-carnitine fumarate from d 260 of gestation to d 20 postpartum. Hepatic triacylglycerides concentration, total carnitine, free carnitine, acylcarnitine, and serum levels of non-esterified fatty acids (NEFA), β-hydroxybutyrate (β-HB) and urea were determined by spectrophotometry. Repeated measures analysis was used to determine the effects of dose, measurement period, and their interactions. Results: Hepatic triglycerides and the different forms of carnitine showed no difference between sampling periods (p>0.05). Hepatic triglycerides concentration was low and decreased in response to 200 g/d L-carnitine fumarate supplementation (p<0.05). This decrease in hepatic triglycerides could be due to increased fatty acid oxidation. L-carnitine supplementation significantly increased (p<0.05) blood urea concentration, possibly through stimulation of the urea cycle, as previously described in other species. Conclusion: Supplementation with L-carnitine decreased the hepatic concentration of triglycerides, possibly due to increased liver oxidation of fatty acids.

Resumen Antecedentes: El incremento en la utilización de reservas corporales durante el periparto en vacas exige una alta disponibilidad de L-carnitina, la cual puede ser limitante bajo las condiciones propias de producción del trópico alto colombiano. Objetivo: Evaluar el potencial lipotrópico de la L-carnitina en vacas lecheras Holstein durante el periodo de transición a la lactancia. Métodos: Se suministraron dosis de 0, 100 y 200 g/d de fumarato de L-carnitina a 21 vacas Holstein a partir del d 260 de gestación y hasta el d 20 postparto. Se determinaron las concentraciones hepáticas de triacilglicéridos, carnitina total, carnitina libre y acil carnitina, y las concentraciones plasmáticas de ácidos grasos no esterificados (NEFA), β-hidroxibutirato (β-HB) y urea. Un análisis de medidas repetidas fue usado para determinar los efectos de la dosis, el periodo de medición, y sus interacciones. Resultados: Las concentraciones hepáticas de triglicéridos y de las diferentes formas de carnitina no difirieron significativamente (p>0,05) entre periodos de muestreo. La concentración hepática de triglicéridos fue baja, y mostró una disminución significativa (p<0,05) en respuesta a la suplementación con 200 g/d de fumarato de L-carnitina. La disminución en los triglicéridos hepáticos podría deberse a un aumento en la oxidación de ácidos grasos. La suplementación con L-carnitina aumentó significativamente (p<0,05) la concentración de urea en sangre, posiblemente a través de un mecanismo de estimulación del ciclo de la urea, descrito previamente en otras especies. Conclusión: La suplementación con L-carnitina disminuyó la concentración hepatica de trigliceridos, debido posiblemente a un aumento en la oxidación de ácidos grasos en hígado.

Resumo Antecedentes: O aumento do uso de reservas corporais durante o periparto requer alta disponibilidade de L-carnitina, que pode ser limitante nas condições de produção no trópico alto colombiano. Objetivo: Avaliar o potencial lipotrópico da L-carnitina em vacas leiteiras Holstein durante o período de transição para a lactação. Métodos: Quantidades de 0, 100 e 200 g/d de fumarato de L-carnitina foram administradas a 21 vacas holandesas durante o d 260 da gestação e até ao d 20 pós-parto. Foram determinadas as concentrações hepáticas de triacilglicerídeos, carnitina total, carnitina livre e acil carnitina e as concentrações plasmáticas de ácidos graxos não esterificados (NEFA), β-hidroxibutirato (β-HB) e ureia. Uma análise das medidas repetidas foi usada para determinar os efeitos da dose, período de medição e suas interações. Resultados: As concentrações hepáticas de triglicerídeos e as diferentes formas de carnitina não diferiram significativamente entre os períodos de amostragem (p>0,05). A concentração hepática de triglicerídeos foi baixa e mostrou diminuição significativa (p<0,05) em resposta à suplementação com 200 g/d de fumarato de L-carnitina. A diminuição dos triglicerídeos hepáticos pode ser devido a um aumento na oxidação de ácidos graxos. A suplementação com L-carnitina aumentou significativamente (p<0,05) a concentração de ureia no sangue, possivelmente através de um mecanismo de estimulação do ciclo da ureia previamente descrito em outras espécies. Conclusão: A suplementação com L-carnitina diminuiu a concentração hepática de triglicerídeos, possivelmente devido ao aumento da oxidação de ácidos graxos no fígado.

Low pathogenic avian influenza (H7N6) virus causing an outbreak in commercial Turkey farms in Chile.

In late 2016, an H7N6 low pathogenic avian influenza virus outbreak occurred in domestic turkeys in Central Chile. We characterized the genetic and antigenic properties of the outbreak virus and its experimental transmission in chickens. Our studies demonstrate that the outbreak virus is a reassortment of genes identified from Chilean wild bird viruses between 2013 and 2017 and displays molecular adaptations to poultry and antiviral resistance to adamantanes. Further, these wild bird viruses are also able to transmit in experimentally infected chickens highlighting the need for continued surveillance and improvement of biosecurity in poultry farms.

Ensayo pictórico: descripción del posicionamiento del túnel femoral en distintas técnicas de reconstrucción del ligamento cruzado anterior (lca) / Pictory essay: description of the positioning of the femoral tunnel in different techniques of reconstruction of the anterior cruciate ligament

En la práctica radiológica habitual el radiólogo se encuentra frecuentemente con distintas técnicas de reconstrucción del LCA que debe conocer de manera general para una adecuada descripción e interpretación de los hallazgos. En el presente ensayo pictórico exponemos diferentes tipos de técnica de reconstrucción del LCA, con énfasis en el concepto de reconstrucción anatómica, presentando distintas posiciones del túnel femoral, buscando entregar herramientas al radiólogo para reconocer la normalidad postoperatoria e interpretar posibles complicaciones.

In daily radiological practice, we frequently fid different ACL reconstruction techniques, which we must know in order to achieve adequate interpretation of the fidings. In this pictorial essay, we show different types of LCA reconstruction techniques, highlighting the anatomical reconstruction concept and presenting different positions of the femoral tunnel, seeking to deliver tools to the radiologist in order to recognize the normal postoperative fidings and possible complications.

Tasa de incidencia de mastitis clínica y susceptibilidad antibiótica de patógenos productores de mastitis en ganado lechero del norte de Antioquia, Colombia* / Incidence rate of clinical mastitis and antibiotic susceptibility of mastitis-producing pathogens in dairy cattle from Northern Antioquia, Colombia / Taxa de incidência de mastite clínica e susceptibilidade antibiótica de patógenos produtores de mastite em gado leiteiro do norte de Antioquia, Colômbia

Resumen Introducción: la mastitis se define como la inflamación de la glándula mamaria causante de grandes pérdidas económicas en hatos lecheros, lo que amerita su investigación. Objetivo: determinar la tasa de incidencia de mastitis clínica TIMC, la etiología asociada y la sensibilidad antibiótica de patógenos aislados de casos de mastitis en ganado lechero. Materiales y métodos: se siguieron 37 hatos por 12 meses para el diagnóstico de mastitis cílínica (MC). A las muestras de leche de los casos de MC se les realizó cultivo bacteriológico y a estas, así como a los aislamientos de casos de mastitis subclínica de un estudio previo, se les efectuó prueba de susceptibilidad antibiótica. Para el análisis de la información se utilizó estadística descriptiva estándar. Resultados: TIMC fue de 13,8 casos por 100 vacas-año a riesgo. Se aislaron 188 patógenos totales de casos de MC, entre los cuales el Streptococcus agalactiae, el Streptococcus pyogenes y el Corynebacterium spp. fueron los más frecuentes, con 29,8; 11,7 y 5,9 %, respectivamente. Se halló una alta sensibilidad de las bacterias contagiosas para los antibióticos cloxacilina y cefoperazone. Conclusiones: en el presente estudio se encontró una TIMC de 13,8 casos por 100 vacas-año a riesgo. Los patógenos más prevalentes identificados en casos de MC fueron contagiosos. Se encontró una alta sensibilidad de las bacterias contagiosas para la mayoría de los antibióticos β-lactámicos.

Abstract Introduction: Mastitis is defined as the inflammation of the mammary gland causing great economic losses in dairy herds, which merits investigation. Objective: To determine the incidence rate of clinical mastitis IRCM, associated etiology, and antibiotic sensitivity of pathogens isolated from cases of mastitis in dairy cattle. Materials and methods: 37 herds were followed during 12 months for clinical mastitis (CM) diagnosis. Milk samples from CM cases were bacteriologically cultured, which underwent, along with isolates from subclinical mastitis cases from a previous study, antibiotic susceptibility testing. For data analysis, standard descriptive statistics were used. Results: The IRCM was 13.8 cases per 100 cows-year at risk. A total of 188 pathogens of CM cases were isolated, among which Streptococcus agalactiae, Streptococcus pyogenes, and Corynebacterium spp. were the most frequent, with 29.8%, 11.7%, and 5.9%, respectively. A high susceptibility of contagious bacteria was found for cloxacillin and cefoperazone. Conclusions: The present study found an IRCM of 13.8 cases per 100 cows-year at risk. The most prevalent pathogens identified in cases of CM were contagious. A high sensitivity of contagious bacteria was found for most β-lactam antibiotics.

Resumo Introdução: a mastite se define como a inflamação da glândula mamária causante de grandes perdas econômicas em rebanhos de gado leiteiro, o que justifica a sua pesquisa. Objetivo: determinar a taxa de incidências de mastite clínica TIMC, a etiologia associada e a sensibilidade antibiótica de patógenos isolados de casos de mastite em gado leiteiro. Materiais e métodos: seguiram-se 37 rebanhos bovinos durante 12 meses para o diagnóstico de mastitis clínica (MC). Com as amostras de leite dos casos de MC realizou-se cultivo bacteriológico e a estas, assim como aos isolamentos de casos de mastite subclínica de um estudo prévio, efetuou-se prova de susceptibilidade antibiótica. Para a análise da informação se utilizou estatística descritiva padrão. Resultados: a TIMC foi de 13,8 casos por 100 vacas-ano a risco. Foram isolados 188 patógenos totais de casos de MC, entre os quais o Streptococcus agalactiae, o Streptococcus pyogenes e o Corynebacterium spp. foram os mais frequentes, com 29,8; 11,7 e 5,9 %, respectivamente. Constatou-se uma alta sensibilidade das bactérias contagiosas para os antibióticos cloxacilina e cefoperazone. Conclusões: neste estudo evidenciou-se uma TIMC de 13,8 casos por 100 vacas-ano a risco. Os patógenos mais prevalentes identificados em casos de MC foram contagiosos. Encontrou-se uma alta sensibilidade das bactérias contagiosas para a maioria dos antibióticos β-lactâmicos.

Prevalencia de parásitos gastrointestinales en equinos y factores de riesgo asociados en varias zonas de Antioquia, Colombia / Prevalence of gastrointestinal parasites in equines and associated risk factors in several areas of Antioquia, Colombia / Prevalência de parasitos gastrointestinais em equinos e fatores de risco associados em várias zonas de Antioquia, Colômbia

Resumen Existen pocos reportes de la prevalencia de parásitos gastrointestinales en equinos en Colombia. En este estudio se muestrearon 946 caballos de un total de 204 predios en los municipios de Rionegro y los que comprenden el Valle de Aburrá departamento de Antioquia. La materia fecal fue tomada directamente del recto y procesada por las técnicas de McMaster׳ Baermann y Graham. La prevalencia de parásitos a nivel de predios fue del 563%׳ para Strongylidae׳ 7%׳10 para Strongyloides spp8%׳2 ׳ para Oxyuridae y 03%׳ para Dictyocaulus spp. Desde el punto de vista práctico׳ los más patogénicos y de mayor problema de resistencia son los Cyathostomidos׳ que se incluyen dentro de los Strongylidae y cuya prevalen-cia fue superior al 50%. El OR de presentar Strongylidae es 49% menor en equinos que participan en ferias en comparación con los que no lo hacen. El OR de presentar Strongylidae es 56% menor en equinos que usan pesebrera en comparación con los que no la usan. Por su parte׳ el OR de ser positivo a Oxyuris equi es 88% menor en animales que salen a ferias en comparación con los que no salen a feria y el OR de ser positivo a Oxyuris equi es 366׳ veces mayor en equinos con condición corporal <2 en comparación con equinos de condición corporal >3. Con base en esta información es importante iniciar estudios de resistencia a antihelmínticos y evaluar la relación entre la carga parasitaria y las posibles afecciones clínicas para así determinar el impacto real de estas parasitosis en los equinos de estas regiones.

Abstract There are few reports on the prevalence of gastrointestinal parasites in equines in Colombia. In this study946 ׳ horses were sampled from a total of 204 farms in the municipalities of Rionegro and those that comprise the Valle de Aburrá׳ in the department of Antioquia. Fecal samples were taken directly from the rectum and processed by the McMaster׳ Baermann and Graham techniques. The prevalence of parasites at the farm level was 56.3% for Strongyüdae10.7% ׳ for Strongyloides spp2.8% ׳ for Oxyuridae and 0.3% for Dictyocaulus spp. From a practical point of view׳ the most pathogenic parasites and of greatest resistance concern were the Cyathostomids׳ which are included within the Strongylidae and whose prevalence was greater than 50%. The OR of presenting Strongylidae was 49% lower in equines that participated in fairs compared to those that did not. The OR of presenting Strongylidae was 56% lower in equines that use stables than those not being stalled. A1so׳ the OR of being positive to Oxyuris equi was 88% lower in animals that participate in fairs compared to those that did not׳ and was 3.66 times higher in equines with body condition < 2 in comparison with those of body condition >3. Based on this information it is important to initiate studies that evaluate the state of antihelminthic resistance and the relationship between parasitic load and clinical condition in order to determine the real impact of these parasites on the equines of these regions.

Resumo Existem poucos reportes da prevalência de parasitos gastrointestinais em equinos na Colômbia. Nessa pesquisa foram amostrados 946 cavalos de um total de 204 fazendas nos municípios de Rionegro e dos que formam o Vale de Aburrá׳ no departamento de Antióquia. A matéria fecal foi tirada diretamente do reto e processada pelas técnicas de McMaster׳ Baermann e Graham. A prevalência de parasitos das fazendas foi de 56.3% para Strongylidae7%׳10 ׳ para Strongyloides spp8%׳2 ׳ para Oxyuridae y 0.3% para Dictyocaulus spp. Desde o ponto de vista prático׳ os mais patogênicos e de maior problema de resistência são os Cyathostomidos׳ que estão incluídos dentro dos Stronglylidae e cuja prevalência foi superior ao 50%. O OR de apresentar Strongylidae é 49% menor nos equinos que participam em férias comparado com os que não. O OR de apresentar Strongylidae é 56% menor nos equinos que usam manjedoura comparado com os que não a usam. Por outro lado׳ o OR de ser positivo a Oxyuris equi é 88% menor em animais que vão a férias comparado com os que não vão e o OR de ser positivo a Oxyuris equi é 3.66 vezes maior nos equinos com condição corporal <2 comparado com os equinos de condição corporal >3. Com base nesta informação׳ se conclui que é importante iniciar estudos de resistência a anti-helmínticos e avaliar a relação entre a carga parasitária e as possíveis afecções clínicas para assim determinar o impacto real destas parasitoses nos equinos destas regiões.

Cross-sectional study of 13 Leptospira serovars in cows in a Colombian dairy region / Estudio transversal de 13 serovares de Leptospira en vacas en una región lechera colombiana / Estudo transversal de 13 sorotipos de Leptospira em vacas em uma região leitera colombiana

Abstract Background: Leptospirosis in cattle is recognized as a major cause of reproductive loses due to abortions, early embryonic death, and infertility. The type of Leptospira serovars that are currently circulating in Colombian herds is largely unknown due to the lack of national reports. Objective: The prevalence of antibodies specific to 13 Leptospira spp serovars was investigated in unvaccinated cows from 26 herds in San Pedro de los Milagros (Province of Antioquia) dairy region. Methods: Microscopic agglutination test was used on serum samples, following WHO recommendations. Results: A total of 112/900 (12.4%) of the animals had antibody titers of 1:100 or greater to at least one Leptospira serovar. Of those positive, 34/900 (3,8%) animals seroconverted to two or more serovars. In order of decreasing prevalence, the serovars detected were: hardjo prajitno, pomona, grippotyphosa, tarassovi, copenhageni, canicola, cellodeni and bratislava. There were 28 animals seropositive to serovar hardjo. Conclusion: Our results indicate that leptospirosis should be included as a differential diagnosis for various reproductive problems in this region.

Resumen Antecedentes: La leptospirosis es la mayor causal de pérdidas reproductivas debidas a abortos, muerte embrionaria temprana e infertilidad. Se desconocen los serovares de Leptospira que actualmente se encuentran circulando en el rebaño colombiano debido a la falta de reportes nacionales. Objetivo: Se investigó la prevalencia de anticuerpos específicos para 13 serovares de Leptospira spp en vacas no vacunadas de 26 rebaños en la región lechera de San Pedro de los Milagros (Provincia de Antioquia). Métodos: La prueba de aglutinación microscópica fue empleada en muestras de suero de acuerdo a las recomendaciones de la OMS. Resultados: Un total de 112/900 (12,4%) de los animales presentaron títulos de anticuerpos de 1:100 o superiores para al menos un serovar de Leptospira. Entre los positivos, el 34/900 (3,8%) de los animales presentaron seroconversión para dos o más serovares. En orden decreciente de prevalencia, los serovares detectados fueron: hardjo prajitno, pomona, grippotyphosa, tarassovi, copenhageni, canicola, cellodeni y Bratislava. En total, 28 animales fueron seropositivos al serovar hardjo. Conclusión: La leptospirosis debería ser incluida como diagnóstico diferencial en problemas reproductivos en esta región.

Resumo Antecedentes: Aleptospirose em bovinos é reconhecida como uma das principais causas de perdas reprodutivas devido a abortos, morte embrionária precoce e infertidade. Os sorotipos de Leptospira que estão atualmente em circulação no rebanho colombiano não se conhecem devido à falta de reportes nacionais. Objetivo: Neste estúdio foi investigada a prevalência de anticorpos específicos para 13 sorovares de Leptospira spp em vacas não vacinadas de 26 rebanhos leiteiros da região de San Pedro, Antioquia. Métodos: Foi empregado o teste de aglutinação microscópica (MAT) em amostras de soro de acordo com as recomendações da OMS. Resultados: Um total de 112/900 (12,4%) animais apresentaram títulos de anticorpos de 1:100 ou superiores para pelo menos um sorotipo de Leptospira. Dos animais positivos, 34/900 (3,8%) soroconverteram para dois ou mais sorotipos. A fim de diminuir a prevalência, foram detectados os sorotipos: hardjo, prajitno, pomona, grippotyphosa, tarassovi, copenhageni, canicola, cellodeni e Bratislava. Um total de28 animais foram soropositivos para o sorotipo hardjo. Conclusão: Os resultados indicam que a leptospirose deveria ser incluída nos diagnósticos diferenciais para o diagnóstico diferencial de problemas em doenças reprodutivas nos bovinos de Antioquia.

Factors associated with Mycobacterium avium subsp. paratuberculosis in dairy cows from Northern Antioquia, Colombia / Factores asociados con el estatus serológico de Mycobacterium avium subsp. paratuberculosis en vacas lecheras del norte de Antioquia, Colombia / Fatores associados ao estado sorológico de Mycobacterium avium subsp. paratuberculosis em soro de gado leiteira no norte de Antioquia, Colombia

Summary Background: Johne´s disease (JD) is a severe enteritis that affects ruminants and has been diagnosed in cattle and sheep in Colombia. However, epidemiological information on the disease in this country is scarce. Objective: to identify factors associated with the JD serum enzyme-linked immunosorbent assay (ELISA) status of dairy cows. Methods: a cross-sectional study was carried out in 307 asymptomatic adult Holstein dairy cows from 14 herds in nine districts of Belmira and San Pedro de los Milagros municipalities during November, 2007. From 19 to 25 cows, ≥ 2 years of age were randomly selected and blood sampled from every herd. A commercial ELISA kit was used to analyze sera. Information regarding cow related factors (age, farm-born, parity, and daily milk yield) and herd management practices (i.e. herd size, herd average milk production, current presence of symptomatic animals, cattle purchase, own animals grazing in foreign pastures, feeding of calves before weaning, manure spread on pastures, and sighting of birds in feed storing areas) was collected using questionnaires. Descriptive statistics were computed for all variables and a multivariable logistic regression model was constructed (p<0.05). Results: ten percent (31/307; 95% CI: 7.0-14.0%) of the animals were positive by ELISA. In 70% (10/14) of the herds, ELISA detected at least one positive animal. Cow and herd factors "parity" and "feeding of calves before weaning" showed weak and strong associations with ELISA positive results, respectively. The odds ratio (OR) for JD seropositivity increased 20% (OR = 1.20; 95% CI: 0.98-1.47; p = 0.067) in cows with > 1 parity. The OR was 0.74 times lower (OR = 0.26; 95% CI: 0.096-0.70; p<0.01) in herds feeding calves with pooled colostrum from several cows, compared to herds feeding calves with colostrum from their own dams. Conclusion: JD seroprevalence was 10 and 70% at animal and herd-level, respectively. Cow and herd factors "parity" and "feeding of calves before weaning" showed weak and strong association with positive results, respectively.

Resumen Antecedentes: la enfermedad de Johne (EJ) es una enteritis severa que afecta rumiantes, y ha sido diagnosticada en bovinos y ovejas en Colombia. Sin embargo, la información epidemiológica de la enfermedad en el país es escaza. Objetivo: identificar los factores asociados con el estatus serológico de la EJ mediante ensayo de inmunoabsorción ligado a enzimas (ELISA) en vacas lecheras. Métodos: se realizó un estudio transversal en 307 vacas lecheras adultas asintomáticas de 14 hatos en 9 veredas en los municipios de Belmira y San Pedro de los Milagros, en noviembre de 2007. De cada hato se seleccionaron aleatoriamente 19-25 vacas, mayores de 2 años de edad y se tomaron muestras de sangre. Se utilizó un kit comercial de ELISA para analizar el suero. Se recolectó información mediante cuestionarios sobre características individuales de las vacas y prácticas de manejo de los hatos. Se realizó un estudio estadístico descriptivo para todas las variables de interés y se construyó un modelo de regresión logística multivariada, considerando un nivel de significancia de p<0,05. Resultados: el 10% de los animales fue positivo a ELISA (31/307; 95% CI: 7,0-14%). En el 70% (10/14) de los hatos al menos un animal fue detectado como positivo por ELISA. Los factores a nivel individual y a nivel hato "número de partos" y "tipo de alimentación de terneras antes del destete" mostraron una asociación débil y fuerte con los resultados positivos de ELISA, respectivamente. El odds ratio (OR) para la seropositividad a EJ aumentó en un 20% (OR = 1,20; 95% CI: 0,98-1,47; p = 0,067) en vacas con más de un parto, mientras que fue 0,74 veces menor (OR = 0,26; 95% CI: 0,096-0,70; p<0,01) en hatos que alimentan sus terneras con mezcla de calostro proveniente de varias vacas, en comparación con aquellos hatos que solo utilizan el calostro de la propia madre. Conclusión: la seroprevalencia de EJ fue del 10 y del 70% a nivel individual y a nivel hato, respectivamente. Los factores a nivel individual y a nivel hato "número de partos" y "tipo de alimentación de terneras antes del destete" mostraron una asociación débil y fuerte con los resultados positivos de ELISA, respectivamente.

Resumo Antecedentes: a doença de Johne (DJ) é uma enterite grave que afeta o ruminantes, e tem sido diagnosticada em bovinos e ovinos na Colômbia. No entanto, a informação epidemiológica da doença no país é escassa. Objetivo: identificar os fatores associados ao estado sorológico de DJ em vacas leiteiras por ensaio imunossorvente ligado a enzima (ELISA). Métodos: estudo transversal foi realizado em 307 vacas leiteiras adultos assintomáticos em 9 de 14 aldeias nos municípios de Belmira y San Pedro de los Milagros, em novembro de 2007. Em cada rebanho foram selecionados aleatoriamente 19-25 vacas com mais de 2 anos de idade e amostras de sangue foram tomadas. Um kit de ELISA comercial é utilizado para testar soros. As informações foram coletadas por meio de questionários sobre as características individuais de animais e práticas de gestão do rebanho. A análise estatística descritiva foi realizada para todas as variáveis de interesse e modelo de regressão logística multivariada foi construído, considerando um nível de significância de p<0,05. Resultados: dez por cento dos animais foram positivos no ELISA (31/307; 95% CI: 7,0-14%). No 70% (10/14) os rebanhos pelo menos, um animal foi detectado como positivo por ELISA. Os fatores a nível individual como a nível do rebanho "paridade" e "tipo de alimentação bezerros antes do desmame" mostraram uma associação fraca e forte com os resultados positivos de ELISA, respectivamente. O odds ratio (OR) para DJ soropositividade aumentou em um 20% (OR = 1,20; 95% CI: 0,98-1,47; p = 0,067) em vacas com mais de um nascimento, enquanto era 0,74 vezes menor (OR = 0,26; 95% CI: 0,096-0,70; p<0,01) em rebanhos que alimentam seus filhotes com a mistura de colostro de várias vacas, em comparação com apenas dados de uso que o colostro da mãe. Conclusão: DJ soroprevalência foi de 10 e 70% a nível individual como a nível do rebanho, respectivamente. Os fatores a nível individual e do rebanho "paridade" e "tipo de alimentação bezerros antes do desmame" mostrou fraca associação e forte com os resultados positivos de ELISA, respectivamente.

Evaluation of a decision support strategy for the control of powdery mildew, Erysiphe necator (Schw.) Burr., in grapevine in the central region of Chile.

BACKGROUND: The primary strategy to control powdery mildew in Chilean vineyards involves periodic fungicide spraying, which may lead to many environmental and human health risks. This study aimed to implement and evaluate the effectiveness and economic feasibility of a novel decision support strategy (DSS) to limit the number of treatments against this pathogen. An experiment was conducted between the 2010 and 2013 seasons in two irrigated vine fields, one containing a cultivar of Cabernet Sauvignon (CS) and the other a cultivar of Chardonnay (CH). RESULTS: The results showed that the DSS effectively controlled powdery mildew in CS and CH vine fields, as evidenced by a disease severity lower than 3%, which was lower than that observed in untreated vines (approximately 10 and 40% for CS and CH respectively). The DS strategy required the application of only 2-3 fungicide treatments per season in key vine phenological stages, and the cost fluctuated between $US 322 and 415 ha-1 , which was 40-60% cheaper than the traditional strategy employed by vine growers. CONCLUSION: The decision support strategy evaluated in this trial allows a good control of powdery mildew for various types of epidemic with an early and late initiation. © 2017 Society of Chemical Industry.