The impact of veterinary medicine and animal husbandry on the biophysical characteristics of soils in neotropical agroecosystems

Los agroecosistemas neotropicales son áreas importantes en el escenario mundial en términos de producción ganadera. Por lo tanto, una buena conservación de sus suelos es crucial para garantizar la inocuidad de los alimentos y reducir el impacto de los procesos de degradación de la tierra. La conservación de los suelos neotropicales utilizados para las actividades agropecuarias podría obtenerse utilizando la medicina veterinaria y adoptando nuevos sistemas de pastoreo en los últimos decenios. Se realizó una amplia revisión bibliográfica que ilustra las cuestiones actuales de los agroecosistemas neotropicales, la importancia de sus propiedades del suelo, destacando el papel que desempeñan los escarabajos peloteros dentro de la edafofauna, y los efectos de las prácticas antiparasitarias más comunes, así como algunas alternativas naturales. Por último, presentamos los sistemas de pastoreo adoptados comúnmente y cómo están afectando a las propiedades del suelo y al bienestar de los animales. La conversión de bosques en tierras agrícolas y de pastoreo está alterando la calidad bioquímica de los suelos. Además, el uso de la ivermectina está reduciendo peligrosamente la cantidad total de escarabajos peloteros que son un elemento clave en los procesos de reciclaje de nutrientes. La aplicación de nuevos sistemas de pastoreo (por ejemplo, Voisin, Savory) está fragmentando progresivamente el hábitat de muchas especies. No obstante, también hay algunos beneficios en este tipo de prácticas y se están probando algunas alternativas naturales a los antihelmínticos.The neotropical agroecosystems are important areas in the global scene in terms of livestock production. Therefore, a good conservation of their soils is crucial in order to both guarantee food safety and reduce the impact of land degradation processes. Conservation of neotropical soils used for farming activities could be obtained using veterinary medicine and adopting new grazing systems in the last decades. A wide bibliographical review was carried out which illustrates current issues in neotropical agroecosystems, the importance of their soil properties highlighting the role played by dung beetles within the edaphofauna, and the effects of the most common anti-parasitic practices as well as some natural alternatives. Finally, we present commonly adopted grazing systems and how they are affecting soil properties and animal welfare. The conversion of forest into agricultural and pasture land is altering the biochemical quality of soils. Furthermore, the use of ivermectin is dangerously reducing the total amount of dung beetles that are a key element in nutrient recycling processes. The implementation of new grazing systems (e.g., Voisin, Savory) is progressively fragmenting the habitat of many species. Nevertheless, there are also some benefits in this kind of practices and some natural alternatives to anthelmintics are being tested.• Comisión Europea, IRSES FP7. Proyecto de investigación EcoDrypeerReviewe

Effect of dried leaves of Leucaena leucocephala on rumen fermentation, rumen microbial population, and enteric methane production in crossbred heifers

The effects of dietary inclusion of dried Leucaena leucocephala leaves (DLL) on nutrient digestibility, fermentation parameters, microbial rumen population, and production of enteric methane (CH4) in crossbred heifers were evaluated. Four heifers were used in a 4 × 4 Latin square design consisting of four periods and four levels of inclusion of DLL: 0%, 12%, 24%, and 36% of dry matter (DM) intake. Results showed that DM intake (DMI), organic matter intake, and gross energy intake (GEI) were similar (p > 0.05) among treatments. Apparent digestibility of organic matter, neutral detergent fiber, and energy decreased with increasing levels of DLL in the ration (p 0.05) rumen pH and total volatile fatty acids. Rumen microbial community was not affected (p > 0.05) by treatment. There was a linear reduction (p < 0.05) in CH4 emissions as the levels of DLL in the ration were increased. Results of this study suggest that an inclusion of 12% DM of ration as DLL enhances digestible CP and reduces daily production of enteric CH4 without adversely affecting DMI, rumen microbial population, and fermentation parameters

Effects of Two Intake Levels of \u3cem\u3eLeucaena leucocephala\u3c/em\u3e on Rumen Function of Sheep

Ruminant production systems based on grass pastures often produce poor animal performance as expressed by growth or reproductive rates. The nutrient imbalance affecting rumen function is due to their low energy and protein intake. The incorporation of leguminous forages such as Leucaena leucocephala, in the diet of ruminants, can stimulate rumen function by providing protein-rich forage (Barros-Rodriguez et al. 2012). This increases the availability of compounds such as ammonia, amino acids and peptides as well as branched short-chain fatty acids, which are produced as a result of degradation of proteins. These substances promote fibre breakdown by acting as ruminal growth activators for rumen bacteria, especially cellulolytic bacteria (Hoover and Stokes 1991). This study aimed to evaluate the effects of 2 intake levels of L. leucocephala on rumen function of sheep fed Pennisetum purpureum

Weeds Forage Potential for Ruminant Feeding: Chemical Composition and Kinetics of Rumen Degradation

Systems of ruminant production in the Andean highlands of Ecuador are dominated by monoculture grasses, where producers do not allow association with other plants such as weeds. These systems have small areas of land and the peasants would be wasting feed resources (association) with high nutritional content and secondary compounds that may be beneficial for feeding ruminants improving the nutritional value of grassland. In this context, Castelán et al. (2003) mention that the use of weeds in ruminant nutrition by small producers in temperate areas of Mexico, it becomes the main natural forage resource for livestock to feed round the year, as there great availability. For farmers with limited financial resources this practice is very common, because it represents feeding efficiency with low production costs, because they use non-conventional feed resources. Weed species such as Sicyos deppei G., Jaltomata procumbens (Cav.), Drymaria laxiflora Benth y Lopezia racemosa Cav. contain high levels of ruminal fermentation and high crude protein content, as well as low levels of fiber (Castelán et al., 2003). Under this background, the objective of this research is to determine the chemical composition and in situ ruminal degradation of weeds with forage potential that exist in the grasslands of the Andean highlands of Ecuador

Emisión de metano en ovinos alimentados con Pennisetum purpureum y árboles que contienen taninos condensados

El objetivo fue evaluar el efecto de los taninos condensados (TC) contenidos en el follaje de arbóreas tropicales, sobre el consumo de materia seca y orgánica (CMS, CMO), la digestibilidad de la materia seca (DMS) y emisiones de metano (CH4) en ovinos alimentados con una ración basal de pasto Pennisetum purpureum. Cuatro ovinos de pelo con un peso vivo promedio de 21.6±2.0 kg se sometieron a cuatro tratamientos en un diseño cuadro latino 4 x 4. Los tratamientos fueron P. purpureum (PP), P. purpureum + Havardia albicans (PPHA), P. purpureum + Bursera simaruba (PPBS), y P. purpureum + Acacia pennatula (PPAP); el follaje de las arbóreas se incluyó en 300 g/kg de MS de la ración. El consumo, la digestibilidad y la producción total de metano entérico se midieron por periodos de 23 h. La producción de metano se midió en cajas de respiración de circuito abierto. El consumo y digestibilidad de la MS y materia orgánica (MO) entre los tratamientos PP, PPHA, PPBS y PPAP no se afectaron por la inclusión de los follajes de arbóreas en la ración (P>0.05). Cuando la producción de CH4 se expresó en L/kg del CMS, CMO o consumo de fibra detergente neutro los resultados fueron similares entre tratamientos (PP, PPHA, PPBS y PPAP) (P>0.05). Se concluye que los TC contenidos en el follaje de Havardia albicans, Acacia pennatula y Bursera simaruba no afectaron las emisiones de CH4 al nivel de incorporación de 30 % de la MS; tampoco se observaron efectos en el CMS, CMO, DMS y concentración molar de ácidos grasos volátiles

Role of secondary plant metabolites on enteric methane mitigation in ruminants

The rumen microbiome plays a fundamental role in all ruminant species, it is involved in health, nutrient utilization, detoxification, and methane emissions. Methane is a greenhouse gas which is eructated in large volumes by ruminants grazing extensive grasslands in the tropical regions of the world. Enteric methane is the largest contributor to the emissions of greenhouse gases originating from animal agriculture. A large variety of plants containing secondary metabolites [essential oils (terpenoids), tannins, saponins, and flavonoids] have been evaluated as cattle feedstuffs and changes in volatile fatty acid proportions and methane synthesis in the rumen have been assessed. Alterations to the rumen microbiome may lead to changes in diversity, composition, and structure of the methanogen community. Legumes containing condensed tannins such as Leucaena leucocephala have shown a good methane mitigating effect when fed at levels of up to 30–35% of ration dry matter in cattle as a result of the effect of condensed tannins on rumen bacteria and methanogens. It has been shown that saponins disrupt themembrane of rumen protozoa, thus decreasing the numbers of both protozoa and methanogenic archaea. Trials carried out with cattle housed in respiration chambers have demonstrated the enteric methane mitigation effect in cattle and sheep of tropical legumes such as Enterolobium cyclocarpum and Samanea saman which contain saponins. Essential oils are volatile constituents of terpenoid or non-terpenoid origin which impair energy metabolism of archaea and have shown reductions of up to 26% in enteric methane emissions in ruminants. There is emerging evidence showing the potential of flavonoids as methane mitigating compounds, but more work is required in vivo to confirm preliminary findings. From the information hereby presented, it is clear that plant secondary metabolites can be a rational approach to modulate the rumen microbiome and modify its function, some species of rumen microbes improve protein and fiber degradation and reduce feed energy loss as methane in ruminants fed tropical plant species

Review: Strategies for enteric methane mitigation in cattle fed tropical forages

Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3−) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change

Guía Mexicana para el Diagnóstico y el Tratamiento de la Urticaria

La urticaria es una enfermedad que padece una quinta parte de la población en algún momento de su vida. Las guías inter- nacionales recientes han propuesto unos cambios de fondo en su diagnóstico y tratamiento, por lo que había la necesidad de crear una guía nacional y multidisciplinaria, con base amplia en los gremios de especialistas y médicos de primer contacto en México. ABSTRACT Urticaria is a disease that a fifth of the population shall suffer once in a lifetime. Recent clinical guidelines have proposed some fundamental changes in the diagnosis and treatment of urticaria, making the development of a national, multidisciplinary guideline, with wide acceptability among different professional groups –both specialists and primary health care workers–, necessary in Mexico

Efecto de un Sistema Silvopastoril Intensivo sobre el Perfil de Textura y Composición Físico-Química del Queso Artesanal Tepeque de México

El objetivo del presente estudio fue conocer el efecto de un sistema silvopastoril intensivo (SSPi) basado en el pastoreo a libre acceso de Panicum maximum y Leucaena leucocephala sobre el perfil de textura, composicion fisico quimica y proceso de maduracion del Queso Artesanal Tepeque (QAT), en comparacion con el QAT elaborado en el sistema tradicional de produccion (ST). Se elaboro un lote de 48 quesos, de los cuales 24 se procesaron con leche proveniente del SSPi y 24 del ST. Los quesos de cada sistema fueron divididos en cuatro subgrupos y sometidos a cuatro periodos de maduracion: 10; 45; 80 y 165 dias. Todos los quesos se sometieron a un Analisis de Perfil de Textura (APT). Para determinar el efecto del sistema de alimentacion y los periodos de maduracion sobre el APT se utilizo un diseno experimental completamente al azar. No se observaron diferencias significativas (P>0,05) para la mayoria de los parametros del APT con excepcion de la dureza, la cual fue mayor (P<0,01) en SSPi. Se estima que la mayor dureza del QAT en el SSPi podria ser atribuida al contenido elevado de polifenoles en la Leucaena, los cuales pueden ser transportados al suero y la leche de los animales y por lo tanto al queso. Se plantea la hipotesis de que la presencia de estos compuestos antioxidantes probablemente aminoro la actividad proteolitica de la microflora endogena del queso manteniendo por mas tiempo su matriz de proteina, principal barrera a la deformacion, permitiendo asi el desarrollo de un queso mas duro. Se observaron diferencias significativas (P<0,01) entre los periodos de maduracion del queso, el cual pasa de uno blando y adhesivo al inicio, a uno de textura dura y no adhesivo al final. Se concluye que el SSPi no tiene efectos significativos sobre el perfil general de textura del QAT y sus propiedades fisico-quimicas

Bibliotecas Digitales: Conferencias de la Reunión CUDI Primavera

Presentaciones de los proyectos en Bibliotecas DigitalesCoordinador: Alfredo Sánchez Mesa Bibliotecas Digitales Salón Inglés Biblioteca digital de la Universidad Autónoma de Nuevo León. Avances e innovaciones. Juan Manuel Arreola, Jesús Eduardo Alvarado, Claudia Patricia Santos, (UANL) Nueva versión de la biblioteca virtual el dorado y proyecto world digital library.- Miguel Avila y Javier Solorio (UCOL) Creative Commons: algunos derechos reservados.- León Felipe Sánchez Ambia (Fulton & Fulton)DVD12-2.wmv/RS P 2007 Mesa Bibliotecas Digitales 2-.fl