Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

El objetivo de este trabajo fue determinar la utilidad de la espectroscopia infrarroja transformada de Fourier (IRTF) para detectar larvas musculares de Trichinella spiralis (Owen, 1835) en jamón y salchichas hechas de carne de un cerdo infectado experimentalmente. Las larvas musculares (LM) se buscaron mediante métodos convencionales (digestión artificial y triquinoscopía teñida con tinción de hemalum de Mayer) y por espectroscopia IRTF. Además, se analizó la capacidad infectiva de las larvas encontradas en los productos porcinos. La carga parasitaria fue de 8.5 ± 3 LM/g en jamón y 4.5 ± 1.4 LM/g en salchicha (P<0.0001). Los espectros de los productos porcinos preparados con la carne de un cerdo no infectado fueron diferentes en el rango de 1,700 a 900 cm-1 con respecto a los espectros de los productos de cerdos infectados. En esta región, el glucógeno es el grupo químico más abundante (1,200 y 900 cm-1). La distancia entre las clases entre los productos no infestados y los infestados fue de 10.2 para el jamón y de 5.52 para las salchichas (tres es el valor mínimo para indicar la separación de clases). La capacidad infectiva de las larvas recuperadas de los productos porcinos disminuyó hasta cinco veces en comparación con la de las larvas obtenidas de ratones infectados experimentalmente. Estos resultados muestran que la espectroscopia IRTF es útil para determinar la presencia de larvas de T. spiralis en los alimentos estudiados aquí. Se necesitan más estudios para determinar la influencia de los sabores de la carne en la detección de Trichinella mediante espectroscopia IRTF.

El objetivo de este estudio fue evaluar la presencia del virus del síndrome reproductivo y respiratorio porcino genotipo 2 (VSRRP-2) en Baja California (Baja), así como la estandarización de la técnica qRT-PCR. Se realizó un estudio transversal de 2016 a 2017 en granjas de Baja. Se obtuvieron 97 muestras de sangre de verracos y cerdas clínicamente sanos y no vacunados. Se diseñaron y estandarizaron iniciadores con el fin de realizar pruebas qRT-PCR a partir de la capa leucocitaria. Todos los resultados positivos fueron confirmados por estudios de secuenciación. Se encontró que el 9.3 % de las muestras fueron positivas. Las muestras positivas provinieron del 66.6 % de las regiones muestreadas. Este estudio demuestra la presencia de VSRRP-2 en Baja, por lo tanto, es necesario realizar estudios epidemiológicos para identificar la magnitud del problema y establecer medidas preventivas y de control.

Plant essential oils are increasingly used in the food industry for their antimicrobial, antioxidant and sensory properties. The effects of added oregano essential oil (OEO) in panela cheese (QP) production was evaluated on cheese physicochemical, textural and sensory properties during 15 day’s storage. Two addition levels were used, resulting in three treatments: control with no OEO (QP1); 0.05 g OEO/ L milk (QP2); and 0.10 g OEO/L milk (QP3). In all treatments, cheese pH was highest (P<0.05) on d 1 and lowest on d 15, although it remained higher overall in QP1. Weight and weight loss did not differ between treatments. Color parameters differed minimally between treatments and over time, although increased OEO content pushed b* values towards yellow. Addition of OEO lowered cheese hardness and shear force values. Based on sensory parameters, consumer acceptance was highest (P<0.05) for the control treatment. Addition of OEO generally did not affect cheese physicochemical, textural and sensory characteristics during storage. It did slightly lower hardness and shear force values, and decreased consumer acceptance. If used at adequate levels, oregano essential oil can improve cheese performance during storage without substantially affecting quality parameters.

Grass species forage yield and nutritional value directly affect livestock production performance. They also vary in response to regional climate and soil conditions. Forage yield and nutritional value in Pennisetum purpureum cv. Cuba CT-115 were evaluated at five regrowth ages (30, 45, 60, 75 and 90 d) in three seasons (dry, rainy and northwinds). A completely randomized block design with repeated measures was used, with four replicates per treatment. In all three seasons, maximum height was reached at 75 d: 127.1 cm in the dry season, 151.6 cm in the rainy season and 137.0 cm the northwind season. Forage yield was highest (27.0 t DM ha-1) at 90 d in the rainy season, with a growth rate of 300.2 kg DM ha-1 d-1, 7.3% crude protein and 37.0% in situ digestibility of dry matter. The leaf:stem ratio was highest at 30 d in all seasons, with a 1.65 average value. Crude protein content was highest in the northwind season at 30 and 45 d, with a 15.6 % average value. In all three seasons, digestibility was highest at 30 (mean= 49.3 %), 45 (51.8 %) and 60 d (48.2 %). Based on forage yield, use of P. purpureum cv. Cuba CT-115 grass for open grazing is recommended for cutting at 90 days’ regrowth and based on its nutritional quality is recommended for grazing at 60 days’ regrowth, both during the rainy season.

The honeybee, Apis mellifera, is a species that, since its introduction to Mexico, has had great social, cultural and economic importance, representing an important source of income for thousands of families who are engaged in beekeeping. However, in the context of the so-called “pollinator crisis”, it is considered that we do not know how this phenomenon affects A. mellifera in Mexico. In review, it is analyzed and discussed the information about A. mellifera in Mexico related to the phenomena that affect its distribution, honey production and its ecology, including interactions with the local flora. In general, it is considered that there is a need for an integration of data on beekeeping at the national level, and that there are few studies on the ecology of A. mellifera in Mexico, from the flora they visit, their efficiency as a pollinator and competition with other native bee species. It is believed that increasing studies on A. mellifera will help to predict changes in honey production as well as understand and address threats to these pollinators, contributing to generate better management practices and establish better pollinator conservation strategies that include the presence of A. mellifera.

This article analyzes the prison as a porous and performative setting from three articulated experiences: 1) love/friendship bonds between female prisoners, 2) “tumberas families” and 3) alternative masculinities. For this, a qualitative and participatory research methodology was deployed, which combined semi-structured interviews and the development of a space for cinema-debate in the Women’s Penitentiary Unit No 8 in La Plata, Argentina. The results expose the productive dimension of the prison regime over sexuality, and the multiple ways in which it challenges the body, among them promoting explorations, disorders, and critical possibilities in the face of the hetero norm. However, they also reveal the exercise of sexual- ity and the construction of “affectivities” as ways of going through the confinement. This article constitutes a contribution to prison studies by delving into a little explored variable of power relations within prisons, and to feminist studies since it allows to recognize the drifts of gender and other tensions (concerning the outside) that they retrace themselves in a space where the sexual norm-dissent relationship assumes a new dialectic, meanings, and scope.

The main objective of this article was to understand the configuration processes of political subjectivities, during the initial research training in two hotbeds. The research proposal arose from the need to inquire about these formative scenarios as enablers for actions and reflections that might allow us to approach the configuration of political subjects. Besides the contributions to pedagogical practice, hotbeds are spaces to reflect on science, research and knowledge. Ethnography as a methodological strategy allowed us to approach and immerse ourselves in these contexts, in order to identify through an empirical and collaborative method the practical and formative intents that underlies them. The main results highlighted the hotbed as an academic setting which enables affective ties and reflection on the need to raise the commitment to a politically engaged science.

This article analyzes interest group studies and examines the empirical findings and methodological challenges of two literature areas: 1) the effect of contributions to political campaigns on public decisions and 2) the influence of lobbying on legislative votes. The document points out the methodological limitations of interest group studies and identifies obstacles that prevent the development of this field of study outside the United States and the European Union.

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