Factores moduladores de la estacionalidad reproductiva en ungulados

The aim of the following review is to describe the seasonal reproductive behavior in male and female ungulates, and identify the determinants of reproductive synchrony. Intrinsic and extrinsic factors that influence the reproductive seasonality of ungulates analyzed. Intrinsic factors are related to the same individual such as genotypic and phenotypic characteristics, and implies that the reproductive aspects can not be extrapolated between species and breeds, and are modified by the action of external factors such as photoperiod, availability of food, temperature, latitude, among others. Among these factors are identified primarily photoperiod and food availability. The photoperiod and food availability are the main signals that determine melatonin levels, and this modulates the reproductive function. Photoperiod is related to the intensity of light and darkness that animals are exposed to and is expressed in the production of melatonin. They describe that the mechanisms of action of this hormone in the central nervous system (CNS) to exert their effects on reproductive function. The nutritional factor is also an important regulator of reproductive seasonality, which could be stimulating the hypothalamic pituitary gland, causing a direct effect on LH release. Then endocrine basis regulating reproductive seasonality in species belonging to the subclass Eutheria, families Bovidae, Camelidae, Equidae and Suidae, wild and domestic, stating differences between them are discussed.  El presente trabajo tiene como objetivo describir el comportamiento reproductivo estacional en ungulados hembras y machos, y la identificación de los factores que determinan la sincronía reproductiva. Se analizan los factores intrínsecos y extrínsecos que influyen en la estacionalidad reproductiva de ungulados. Los factores intrínsecos están relacionados con el mismo individuo ya sean características genotípicas y fenotípicas lo que implica que los aspectos reproductivos no pueden extrapolarse entre las distintas especies y se modifican por la acción de los factores externos como el fotoperiodo, disponibilidad de alimento, temperatura, latitud, entre otros. Dentro de los factores extrínsecos se identifican principalmente el fotoperiodo que está relacionado con la intensidad de luz y oscuridad a la que están expuestos los animales expresándose en la producción de melatonina, se describen los mecanismos de acción de esta hormona a nivel del sistema nervioso central (SNC), y sus efectos sobre la función reproductiva y por otro lado el factor nutricional que también es un importante regulador de la estacionalidad reproductiva, que podría estar estimulando el eje hipotálamo hipófisis, causando un efecto directo sobre la liberación de LH. A continuación se discuten las bases endocrinas que regulan la estacionalidad reproductiva comparada en especies pertenecientes a la subclase Eutheria, familias Bovidae, Camelidae, Equidae y Suidae, salvajes y domésticas. PALABRAS CLAVE: Estacionalidad, reproducción, ungulados, fotoperiodo, nutrición, ciclos reproductivos

Determinación de glucógeno en músculo de bovinos. Una propuesta de medición rápida

A practical, rapid and inexpensive method for muscle glucose determination is proposed. The method is based on acid digestion of the sample, followed by neutralization of the solution and the subsequent glucose determination using a domestic glucometer for human blood glucose level control. In a pre-experimental phase, the accuracy of this methodology and the titration method was determined, comparing results to pre-established glucose concentrations. There were significant differences between the glucose reading given by the glucometer and the pre-established glucose concentrations and the results given by the titration method. Nevertheless, when discrepancies (bias) were identified, differences resulted non-significant (P = 0.85). Subsequently, muscle glucose concentration (n = 24) was validated in the experimental phase and significant differences were shown between glucose concentration values given by the glucometer and the titration method, the latter considered as a standard method or as a reference (P < 0.0001). Once the sources of discrepancies were identified and removed, the differences observed between the values given by the two methods were not statistically significant (P = 0.99). It was concluded that the glucometer is a potential method for muscle glucose determination, but must be improved.Se propuso un método práctico, rápido y de bajo costo, para determinar glucosa en músculo, basado en una digestión ácida de la muestra de músculo, seguida por una neutralización de la solución y posterior determinación de glucosa, utilizando un glucómetro doméstico, para el control de la glicemia sanguínea. En una etapa pre-experimental se determinó la exactitud de esta metodología respecto al método de titulación, comparando sus lecturas, con concentraciones conocidas de glucosa a través de la dócima de exactitud, resultando diferencias significativas entre las lecturas de glucosa, las concentraciones de glucosa conocidas y las entregadas por el método de titulación. Sin embargo, identificadas las causas de las discrepancias (sesgos), las diferencias resultaron no significativas (P = 0,84 y P = 0,86, para ambos casos, respectivamente). En la etapa experimental, se validaron las concentraciones de glucosa en músculo (n = 24), resultando valores diferentes entre concentraciones de glucosa y la obtenida por el método de titulación, considerado como método de referencia o estándar (P < 0,0001). Una vez identificada y removida la fuente de las discrepancias, los valores entregados por ambos métodos fueron similares (P = 0,99). Se concluyó que el glucómetro es un método potencial para la determinación de glucosa en músculo, más aún cuando se afine la técnica en relación al procesamiento de las muestras, tanto en la extracción de la glucosa desde el músculo, como en el método de comparación de los valores entregados por el glucómetro

Perspectives of abandonment/continuity of typological groups of sheep farms in the semi-arid region of Central Chile

An exploratory study was conducted to analyze combinations of variables that define typological groups that condition the abandonment/continuity of sheep farming in the semi-arid region of Chile. Three typological groups were identified. Group I is made up of middle-aged farmers with the largest flocks. Group II has typical farms from an arid zone, own by elderly male farmers. Group III is located in areas near urban centers and has a greater presence of women farmers. The study allowed to identify the variables that influence the continuity of sheep farmers and to determine strategies that avoid/delay the abandonment of the activity

Cambios hematológicos, bioquímica sanguínea y cortisol sérico en crías de guanaco (lama guanicoe) en cautiverio desde el nacimiento al destete

The purpose of this study was to contribute to the knowledge of the haematological, blood biochemistry and seric cortisol reference values in captive guanacos, which would allow evaluating their health and stress response. We describe haematological, blood biochemistry and seric cortisol changes of from birth to six month of age and the haematological and cortisol response to abrupt and programmed weaning at 6.5 - 7 months old. The main age related changes were on red cells, muscular enzymes and total seric proteins. There were no effects on haematological and cortisol indicators of stress response due to the weaning, thus we could conclude that weaning was not stressful for the animals in this study.El propósito del presente estudio fue contribuir al co­nocimiento de valores de referencia de indicadores hematológicos, bioquímica sanguínea y cortisol séri­co en guanacos en cautiverio que permiten evaluar la salud y respuesta estrés. Se describieron variables hematológicas, bioquímica sanguínea y cortisol séri­co en crías de guanaco en cautiverio, desde el naci­miento a los seis meses de edad y la respuesta hematológica y de cortisol al destete abrupto y pro­gramado, a los 6.5 a 7 meses de edad. Se observaron cambios relacionados con la edad principalmente en la serie roja y proteínas séricas totales, y de enzimas musculares por manipulación. El destete no produjo cambios hematológicos ni de cortisol sérico que se re­lacionen con respuesta estrés, por lo que se concluye que este manejo no fue estresante para los animales

Cambios hematológicos, bioquímica sanguínea y cortisol sérico en crías de guanaco (lama guanicoe) en cautiverio desde el nacimiento al destete

The purpose of this study was to contribute to the knowledge of the haematological, blood biochemistry and seric cortisol reference values in captive guanacos, which would allow evaluating their health and stress response. We describe haematological, blood biochemistry and seric cortisol changes of from birth to six month of age and the haematological and cortisol response to abrupt and programmed weaning at 6.5 - 7 months old. The main age related changes were on red cells, muscular enzymes and total seric proteins. There were no effects on haematological and cortisol indicators of stress response due to the weaning, thus we could conclude that weaning was not stressful for the animals in this study.El propósito del presente estudio fue contribuir al co­nocimiento de valores de referencia de indicadores hematológicos, bioquímica sanguínea y cortisol séri­co en guanacos en cautiverio que permiten evaluar la salud y respuesta estrés. Se describieron variables hematológicas, bioquímica sanguínea y cortisol séri­co en crías de guanaco en cautiverio, desde el naci­miento a los seis meses de edad y la respuesta hematológica y de cortisol al destete abrupto y pro­gramado, a los 6.5 a 7 meses de edad. Se observaron cambios relacionados con la edad principalmente en la serie roja y proteínas séricas totales, y de enzimas musculares por manipulación. El destete no produjo cambios hematológicos ni de cortisol sérico que se re­lacionen con respuesta estrés, por lo que se concluye que este manejo no fue estresante para los animales

Incidence and clinical manifestations of giant cell arteritis in Spain: results of the ARTESER register

Objective This study aimed to estimate the incidence of giant cell arteritis (GCA) in Spain and to analyse its clinical manifestations, and distribution by age group, sex, geographical area and season.Methods We included all patients diagnosed with GCA between 1 June 2013 and 29 March 2019 at 26 hospitals of the National Health System. They had to be aged ≥50 years and have at least one positive results in an objective diagnostic test (biopsy or imaging techniques), meet 3/5 of the 1990 American College of Rheumatology classification criteria or have a clinical diagnosis based on the expert opinion of the physician in charge. We calculated incidence rate using Poisson regression and assessed the influence of age, sex, geographical area and season.Results We identified 1675 cases of GCA with a mean age at diagnosis of 76.9±8.3 years. The annual incidence was estimated at 7.42 (95% CI 6.57 to 8.27) cases of GCA per 100 000 people ≥50 years with a peak for patients aged 80–84 years (23.06 (95% CI 20.89 to 25.4)). The incidence was greater in women (10.06 (95% CI 8.7 to 11.5)) than in men (4.83 (95% CI 3.8 to 5.9)). No significant differences were found between geographical distribution and incidence throughout the year (p=0.125). The phenotypes at diagnosis were cranial in 1091 patients, extracranial in 337 patients and mixed in 170 patients.Conclusions This is the first study to estimate the incidence of GCA in Spain at a national level. We found a predominance among women and during the ninth decade of life with no clear variability according to geographical area or seasons of the year

International eDelphi Study to Reach Consensus on the Methotrexate Dosing Regimen in Patients with Psoriasis

Importance: A clear dosing regimen for methotrexate in psoriasis is lacking, and this might lead to a suboptimal treatment. Because methotrexate is affordable and globally available, a uniform dosing regimen could potentially optimize the treatment of patients with psoriasis worldwide. Objective: To reach international consensus among psoriasis experts on a uniform dosing regimen for treatment with methotrexate in adult and pediatric patients with psoriasis and identify potential future research topics. Design, Setting, and Participants: Between September 2020 and March 2021, a survey study with a modified eDelphi procedure that was developed and distributed by the Amsterdam University Medical Center and completed by 180 participants worldwide (55 [30.6%] resided in non-Western countries) was conducted in 3 rounds. The proposals on which no consensus was reached were discussed in a conference meeting (June 2021). Participants voted on 21 proposals with a 9-point scale (1-3 disagree, 4-6 neither agree nor disagree, 7-9 agree) and were recruited through the Skin Inflammation and Psoriasis International Network and European Academy of Dermatology and Venereology in June 2020. Apart from being a dermatologist/dermatology resident, there were no specific criteria for participation in the survey. The participants worked mainly at a university hospital (97 [53.9%]) and were experienced in treating patients with psoriasis with methotrexate (163 [91.6%] had more than 10 years of experience). Main Outcomes and Measures: In a survey with eDelphi procedure, we tried to reach consensus on 21 proposals. Consensus was defined as less than 15% voting disagree (1-3). For the consensus meeting, consensus was defined as less than 30% voting disagree. Results: Of 251 participants, 180 (71.7%) completed all 3 survey rounds, and 58 participants (23.1%) joined the conference meeting. Consensus was achieved on 11 proposals in round 1, 3 proposals in round 2, and 2 proposals in round 3. In the consensus meeting, consensus was achieved on 4 proposals. More research is needed, especially for the proposals on folic acid and the dosing of methotrexate for treating subpopulations such as children and vulnerable patients. Conclusions and Relevance: In this eDelphi consensus study, consensus was reached on 20 of 21 proposals involving methotrexate dosing in patients with psoriasis. This consensus may potentially be used to harmonize the treatment with methotrexate in patients with psoriasis.