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

Surgical castration has been a common practice in pigs to prevent boar taint, however, it affects animal welfare. Immunocastration has been used as an alternative approach; it involves the administration of a vaccine that stimulates the production of antibodies directed against the GnRH hormone. This induces a temporary inhibition of testicular function accompanied by the release of steroids known to generate the characteristic boar taint odor. Substantial published information documents the utilization of this intervention, yielding variable outcomes for productive performance. The present study was conducted to evaluate the effect of the application of the anti-GnRH vaccine on productive performance and carcass quality in pigs. Sixteen meta-analyses were performed to determine the effect size, with two types of control groups (castrated and entire males), from 45 scientific articles (3,685 repetitions) under a random effects model. Results show that the utilization of the anti-GnRH vaccine significantly improved daily feed intake [DFI] (-78.78 g day-1, p = 0.00028), feed conversion [FC] (-168.54 g kg-1, p < 0.00001), feed efficiency [FE] (+35.58 g kg-1, p < 0.00001) and lean percentage (+1.3%, p < 0.00001), in comparison with surgically castrated males. Control non-castrated pigs presented superior outcomes for all variables analyzed, except for daily weight gain (+32.67 g day-1, p = 0.00005), which was favored by the use of the vaccine. It is concluded that the use of the anti-GnRH vaccine favors productive performance (DFI, FC and FE) compared to surgically castrated pigs, but not versus entire pigs.

The study focuses on proposing agroforestry associations to characterize and evaluate the sustainability of farms in the Santo Domingo canton. This approach could promote the farm’s long-term viability and contribute to the region’s sustainable rural development, as agriculture and livestock are vital to the local economy. The non-experimental methodology employed included direct observation, documentary analysis, and surveys, that addressed the economic, environmental, and social dimensions of sustainability. The results showed that only 20% of the farms are fully sustainable, meeting all three sustainability indicators and achieving an overall index of at least two. Four farms were classified as sustainable: three in the Puerto Limón parish and one in Valle Hermoso. The remaining farms in the canton reflect a limited proportion of integral sustainability. In terms of income, farms primarily rely on the sale of cocoa and plantains. Expenditures are allocated to inputs, tools, transportation, and occasional labor. The most significant socioeconomic limitations identified were low education levels and economic risk, while the main challenges identified at the production level were limited crop diversity and soil nutrient depletion. These findings underscore the urgent need for strategies that strengthen the sustainability of agricultural and livestock production and enhance community resilience and social cohesion. Proposed agroforestry associations could optimize resource use, foster biodiversity, and ensure a more viable future for these rural communities.

In Nicaragua, two taro cultivars (Lila and Blanca) (Colocasia esculenta L. Schott) are cultivated, yet neither cultivar exhibits tolerance to biotic or abiotic factors. The crop requires abundant water, and in Nicaragua the rainy season is insufficient to meet water requirements for this crop. Gamma radiation has been identified as a tool to accelerate plant breeding programs. The present study evaluated the effect of gamma ray irradiation as a source of mutation induction in the morphology of two taro cultivars. In vitro plants of Lila and Blanca taro were irradiated with 0 (control), 5, 10, 15, 20, 25 and 30 Gy of gamma rays. The variables evaluated were plant height (cm), leaf number, shoot number, root number, survival percentage, 50% growth reduction dose [DR50] and 50% lethal dose [DL50]. In both cultivars the variables presented a negative correlation with the irradiation doses; as the doses increased, plant height, number of leaves, shoots and roots decreased. The optimal irradiation doses for Lila taro were determined to be 10, 13 and 16 Gy, while for Blanca taro these doses were 20, 25 and 30 Gy.  In the case of Blanca taro, 100% survival was recorded in the control and at the 5 and 10 Gy doses. In the case of Lila taro, 100% survival was recorded in the control and at the 5 Gy dose. The LD50 in Lila taro was determined to be 19 Gy, while in Blanca taro, the LD50 was established as 53 Gy.

In the first half of 2024, Ecuador received a total of 589,082 tourists, with an annual growth rate of 12.77%, and an increase in jobs of 5.12%, representing a participation of the tourism sector in the GDP of 2.06%. However, a review of the state of the art shows several methodologies and tools contribute to the development of rural tourism sites and destinations, which are applied according to the characteristics of each territory analyzed. Therefore, our objective was to determine, through the cluster method, the classification, decision-making, and the different tourist routes and circuits that will strengthen the development of rural areas in the province of Azuay. The proposed methodology allows for the identification of four clusters to be taken into account when planning a tourist circuit or route. The most important cluster is nature with 46.6%, followed by gastronomy and art and culture with 40%, and finally adventure with 13.3%.

More than 70% of Ecuador’s goat population is found in the south of the country, where they are managed in open fields, with little technological application and support. The objective was to determine the performance of these animals at hot and cold carcasses and the degree of runoff. A total of 457 goats of different ages, genetic groups, and biotypes, slaughtered at the Municipal Slaughter Center of Zapotillo, were included in the study. Information on ante-mortem weights, and hot and cold carcasses was collected, and factors such as sex, age, breed group, and biotype were included in the analysis using an ANOVA with a randomized linear model. The results show a hot and cold carcass yield of 41.8± 2.6% and 41.1± 2.7% respectively, with no statistical difference in the factors analyzed. It is highlighted that carcass yield decreases minimally with increasing age; males present a slightly higher carcass yield (41.9%) compared to females (41.7%); regarding the breed, there were also slight differences with Chuscos Criollos, Mestizos and Anglo Nubian, presenting 41.8%, 42.1% and 41% of the hot carcass yield respectively; analyzing the biotype, presence and absence of horns, the yield was 41.8% and 41.9 % respectively. It is important to note that there was a minimal level of runoff in this population (1.23%). We conclude that these goats have a low carcass yield compared to other populations, possibly due to the type of management and feeding, where water scarcity predominates. It is worth noting the slight superiority of the Mestizo breed, which could be a good option for improving these variables.

Nutrition is a limiting factor in cattle productivity. Since information on micronutrient deficiencies and on the efficiency of the use of technologies applied in assisted reproduction technologies in pasture raised cows is scarce, it is important to know the influence of vitamin E, A, β-carotene and trace minerals such as selenium. The aim of this bibliographic review was to determine the influence of vitamin E, A, β-carotene and trace minerals such as selenium, copper, zinc, manganese and iron on the health and efficiency of assisted reproduction techniques in female cattle. These dietary components play an important role in the antioxidant mechanism and the responsiveness of the immune system in the body and are associated with parameters such as health status, reproductive performance and efficiency of assisted reproduction techniques. Deficiencies of some of these nutrients reduce the immune response, increase susceptibility to infections, reduce fertility and the efficacy of new reproductive biotechnologies, especially in pasture-raised cows in the tropics. Supplementation of these micronutrients can help improve the health, reproductive performance and technologies for estrus induction and synchronization, embryo transfer and in vitro embryo production in female cattle in areas where these nutritional deficiencies persist.

Debido a su amplio uso, las redes inalámbricas en concordancia con los estándares IEEE 802.11g/n pueden experimentar saturación de canal, lo que genera interferencias que afectan su rendimiento. Este estudio analiza el rendimiento de estas redes en diferentes escenarios de interferencia, evaluando su comportamiento en términos de métricas de Calidad de Servicio, como rendimiento, retardo, jitter y pérdida de paquetes. Se realizaron experimentos en interiores utilizando dos estándares, IEEE 802.11g/n, y diferentes configuraciones de canal. Inicialmente, las redes se evaluaron en escenarios donde todos los dispositivos operaban en el mismo canal (1, 6 u 11), lo que generaba interferencia cocanal. Posteriormente, se analizaron escenarios donde cada punto de acceso operaba en un canal diferente para minimizar la interferencia. Se empleó la técnica de inyección de tráfico intrusivo para la recopilación de datos, lo que permitió mediciones precisas de las métricas analizadas. Los resultados indican que el rendimiento de la red varía significativamente según el estándar utilizado y la configuración del canal. En general, las redes que operan bajo el estándar IEEE 802.11n mostraron un mejor rendimiento, pero fueron más susceptibles a las interferencias en comparación con IEEE 802.11g. Además, la eficiencia de transmisión disminuyó significativamente en presencia de interferencia con pérdidas de rendimiento de hasta un 35 % en algunos escenarios. Estos hallazgos resaltan la importancia de una planificación adecuada de canales en las redes inalámbricas para optimizar el rendimiento y minimizar los efectos adversos de las interferencias.

En este trabajo se presenta una guía práctica para el diseño de una antena de microcinta, circularmente polarizada a derecha (RHCP), usando el software HFSS. Este procedimiento se aplica al diseño de una antena para adquirir la información transmitida por el sistema de posicionamiento global (GPS), en la banda L1, que se utiliza en la unidad de control de actitud (ACU) para el mejoramiento del control de la actitud de un microsatélite viajando en una órbita baja (LEO). Valores para la razón axial (AR) de 1,22 dB, una directividad de 5,14 dB en la dirección Broadside, y un ancho de banda para la RA de 15 MHz fueron obtenidos siguiendo el procedimiento propuesto. 

En este estudio, se investigó el rendimiento de las redes inalámbricas IEEE 802.11g e IEEE 802.11n en diferentes escenarios de interferencia. Las métricas de calidad de servicio incluyen el rendimiento, el retraso o la variabilidad del retraso y la tasa de paquetes perdidos. Los experimentos realizados en entornos de intraapartamento comenzaron con interferencia cocanal, con todos los dispositivos conectados en el mismo canal. A continuación, cada uno emitido en un canal diferente, minimizando así la interferencia. El tráfico intrusivo en el protocolo se utilizó para mediciones precisas de las métricas. Los resultados indican que el rendimiento varía según el estándar y la configuración del canal. En términos generales, IEEE 802.11n ofrece un rendimiento superior, aunque es más susceptible a las interferencias en comparación con IEEE 802.11g. La eficiencia de la transmisión se ve afectada de manera significativa en presencia de interferencia cocanal, con pérdidas de rendimiento que pueden alcanzar hasta un 35 % en ciertos escenarios. Este estudio subraya la importancia de una planificación adecuada de los canales para maximizar el rendimiento y mitigar los efectos negativos de la interferencia.

Este trabajo presenta una revisión sistemática de estudios relevantes publicados entre los años 2019 y 2024, centrados en los protocolos de seguridad de datos en entornos de computación en la nube. La selección de artículos se realizó mediante criterios rigurosos, con el objetivo de identificar las características más destacadas de estos protocolos y sus aplicaciones actuales. Se analizan tanto sus ventajas como los mecanismos criptográficos utilizados para proteger la información sensible, entre los que se encuentran AES, RSA y ECC. Adicionalmente, se considera el creciente uso de Kubernetes como herramienta de orquestación de contenedores, reconociendo su importancia dentro de las infraestructuras modernas en la nube. En este contexto, se examinan diversas publicaciones que evidencian limitaciones en su implementación, tales como la gestión inadecuada de privilegios y la dependencia de soluciones de terceros. El estudio ofrece una visión integral que facilite la comprensión de los desafíos actuales y oriente la búsqueda de soluciones que fortalezcan la seguridad en entornos cloud.