Fasciola hepatica and Rumen Flukes - In Vitro Evaluation of Main Commercial Anthelmintics

Background: Trematode infections are of great importance as they affect the health of many species of mammals as cattle, sheep and goat. Fasciola hepatica represents the main trematode zoonosis and risks to human and cattle and paramphistomosis is one emerging parasitic diseases of ruminants widely distributed in the world. The economic expenses are incurred by the use of ineffective anthelmintics for trematode control. Besides to faecal egg count reduction test (FECRT) to determine the anthelmintic efficacy, can be used in vitro assays, by this the aim of the study was to determine the lethal doses with hatching egg test of the main commercial anthelmintics used for the control of trematodes in cattle. Materials, Methods & Results: Liver and rumen were examined from cattle slaughtered in Tabasco, Chiapas and Campeche states from Mexico. F. hepatica eggs were recovered from gallbladder and rumen fluke eggs collected from adult parasites in saline solution. Subsequently, the hatching egg assays were performed placing 100 trematode eggs in distilled water in each one of 96 wells of polystyrene plates. After making the appropriate dilutions, several concentrations of commercial anthelmintics were evaluated, ranging from 0.04 to 80.63 mM for triclabendazole + 0.046 to 96.87 mM febendazole (TC+FBZ), from 0.04 to 91 mM for rafoxanide (RAFOX), from 0.02 to 43.74 mM for closantel (CLOS), from 0.036 to 76.18 mM for clorsulon + 0.002 to 3.31 mM ivermectin (CLORS+ IVM) and from 0.163 to 334.47 mM for nitroxynil (NITROX). A control group (water) was included in each plate. Lethal doses were obtained using the Probit procedure and analysis of the means with a one-way statistical design. Most drugs used against rumen fluke eggs presented a high LD50 and therefore were ineffective to cause egg mortality, such was the case of RAFOX that presented LD50 from 4,580 to 10,790 µg/mL (7 to 17 mM). CLOS presented the lowest LD50 (80 µg/mL or 0.12 mM) on rumen fluke eggs. TC+FBZ was found to be effective drug against the development of F. hepatica eggs in many samples. In the same way NITROX showed a low LD50 (37 to 63 µg/mL or 0.13 to 0.22 mM), but RAFOX presented a highest LD50 (1,450 µg/mL or 2.32 mM). Discussion: The present study focused on screen the ovicidal activity and determining in vitro lethal doses 50 of main commercial anthelmintics used to control F. hepatica and rumen fluke as rapid tests in a tropical region from Mexico. The FECRT is the main method to detect effectiveness of anthelmintic and other method is the coproantigen reduction test (CRT) by ELISA. Both tests require many infected animals depending the number of treatments and by this the egg hatch assay (EHA) represent a complementary diagnosis of effectiveness of anthelmintic products to compare between regions and even between farms, because few animals are required from the farm to collect trematode eggs, and it is possible to know the effectiveness against various anthelmintics at the same time. Efficacy studies on trematodes using egg hatching tests are scarce, although they have the advantage that they can be applied to both F. hepatica and rumen fluke. TC+FBZ was one of the most effective products in inhibiting the development of F. hepatica eggs. However, RAFOX showed low effectiveness against trematode eggs, with very high lethal doses. These results agree with a study that show low efficacy against the development of Paramphistomum cervi eggs and with the FECRT test reductions of 75% and 80.58% were obtained, in times from 7 to 84 days after treatment with RAFOX. NITROX and CLORS were drugs that had good efficacy on the development of F. hepatica eggs. A differential response between liver and rumen fluke was observed. The anthelmintics used against rumen fluke eggs show low ovicidal activity and in Fasciola hepatica TC+FBZ show the best activity. Keywords: trematodes, cattle, effectiveness, anthelmintics, ovicidal activity, egg hatching

Foucault test: shadowgram modeling from the physical theory for quantitative evaluations

The physical theory of the Foucault test has been investigated to represent the complex amplitude and irradiance of the shadowgram in terms of the wavefront error; however, most of the studies have limited the treatment for the particular case of nearly diffraction-limited optical devices (i.e., aberrations smaller than the wavelength). In this paper we discard this restriction, and in order to show a more precise interpretation from the physical theory we derive expressions for the complex amplitude and the irradiance over an optical device with larger aberrations. To the best of our knowledge, it is the first time an expression is obtained in closed form. As will be seen, the result of this derivation is obtained using some properties of the Hilbert transform that permit representing the irradiance in a simple form in terms of the partial derivatives of the wavefront error. Additionally, we briefly describe from this point of view a methodology for the quantitative analysis of the test

Acoustic individual identification in birds based on the band-limited phase-only correlation function

A new technique based on the Band-Limited Phase-Only Correlation (BLPOC) function to deal with acoustic individual identification is proposed in this paper. This is a biometric technique suitable for limited data individual bird identification. The main advantage of this new technique, in contrast to traditional algorithms where the use of large-scale datasets is assumed, is its ability to identify individuals by the use of only two samples from the bird species. The proposed technique has two variants (depending on the method used to analyze and extract the bird vocalization from records): automatic individual verification algorithm and semi-automatic individual verification algorithm. The evaluation of the automatic algorithm shows an average precision that is over 80% for the identification comparatives. It is shown that the efficiencies of the algorithms depend on the complexity of the vocalizations

Bayesian nonparametric mrf and entropy estimation for robust image filtering

We introduce an approach for image filtering in a Bayesian framework. In this case, the probability density function (pdf) of the likelihood function is approximated using the concept of non-parametric or kernel estimation. The method is complemented using Márkov random fields, for instance the Semi-Huber Markov random field (SHMRF), which is used as prior information into the Bayesian rule, and the principal objective of it is to eliminate those effects caused by the excessive smoothness on the reconstruction process of signals which are rich in discontinuities. Accordingly to the hypothesis made for the present work, it is assumed a limited knowl- edge of the noise pdf, so the idea is to use a non-parametric estimator to estimate such a pdf and then apply the entropy to construct the cost function for the likelihood term. The previous idea leads to the construction of new Maximum a posteriori (MAP) robust estimators, and considering that real systems are always exposed to continuous perturbations of unknown nature. Some promising results have been obtained from two new MAP entropy estimators (MAPEE) for the case of robust image filtering, where such results have been compared with respect to the classical median image filter

Rescue and participatory conservation of Creole goats in the agro-silvopastoral systems of the Mountains of Guerrero, Mexico

The objective was to implement a participatory process involving rescue and conservation of Creole goats in agro-silvopastoral systems, as a development strategy for the indigenous and marginalized region of the Mountains of Guerrero (MG), Mexico. The study focused on the caprine agroecosystem, documenting aspects of goat development and identifying caprine areas in 13 municipalities, zoometrically characterizing 680 goats. One hundred and ten goat producers were interviewed for evaluating farmer perception of goat production. Fifty-seven producers were trained in holistic management, and four producers raised 300 goats in outstanding herds. Data were analyzed using social networks, principal component analysis and correspondence analysis. Two goat agroecosystems were identified: 1) agro-silvopastoralism, with crossbreeding of goat populations and, 2) traditional systems, involving grazing of Creole goats on native vegetation. We identified three types of goats: 1) Mixteco mosaic (61%), 2), Pastoreña (31.8%), and 3) Crossbreeds (7.2%), based on bicoastal diameter, chest depth, body length, thoracic perimeter, height at withers, shoulder point width and liveweight. Smallholder goat farmers in the MG preferred Creole goats for their greater productivity and better environmental adaptation. Highlights: Farmer-participatory programs to rescue and conserve the Creole goat breed. Goats agro-silvopastoral systems with low resource smallholders. Sustainable utilization of Creole goats. Goat production systems in the Mexican Mountains.The objective was to implement a participatory process involving rescue and conservation of Creole goats in agro-silvopastoral systems, as a development strategy for the indigenous and marginalized region of the Mountains of Guerrero (MG), Mexico. The study focused on the caprine agroecosystem, documenting aspects of goat development and identifying caprine areas in 13 municipalities, zoometrically characterizing 680 goats. One hundred and ten goat producers were interviewed for evaluating farmer perception of goat production. Fifty-seven producers were trained in holistic management, and four producers raised 300 goats in outstanding herds. Data were analyzed using social networks, principal component analysis and correspondence analysis. Two goat agroecosystems were identified: 1) agro-silvopastoralism, with crossbreeding of goat populations and, 2) traditional systems, involving grazing of Creole goats on native vegetation. We identified three types of goats: 1) Mixteco mosaic (61%), 2), Pastoreña (31.8%), and 3) Crossbreeds (7.2%), based on bicoastal diameter, chest depth, body length, thoracic perimeter, height at withers, shoulder point width and liveweight. Smallholder goat farmers in the MG preferred Creole goats for their greater productivity and better environmental adaptation. Highlights: Farmer-participatory programs to rescue and conserve the Creole goat breed. Goats agro-silvopastoral systems with low resource smallholders. Sustainable utilization of Creole goats. Goat production systems in the Mexican Mountains

La tecnología MEMS como auxiliar en el posicionamiento GPS a bajo costo

Hoy en día la navegación por GPS es una herramienta cotidiana muy útil para la humanidad, gracias a esta tecnología las personas pueden desplazarse por lugares en los cuales no han estado antes con cierto grado de precisión. La ubicación de un punto sobre la superficie terrestre se hace por medio de un satélite transmisor y un receptor que se ubica por medio del principio de Triangulación. Los Sistemas-Micro-Electro-Mecánicos o MEMS, son una tecnología que, en su forma más general puede ser definida como elementos electro mecánicos miniaturizados que se realizan con técnicas de micro-fabricación

LA TECNOLOGÍA MEMS COMO AUXILIAR EN EL POSICIONAMIENTO GPS A BAJO COSTO

Hoy en día la navegación por GPS es una herramienta cotidiana muy útil para la humanidad, gracias a esta tecnología las personas pueden desplazarse por lugares en los cuales no han estado antes con cierto grado de precisión. La ubicación de un punto sobre la superficie terrestre se hace por medio de un satélite transmisor y un receptor que se ubica por medio del principio de Triangulación. Los Sistemas-Micro-Electro-Mecánicos o MEMS, son una tecnología que, en su forma más general puede ser definida como elementos electro-mecánicos miniaturizados que se realizan con técnicas de micro -fabricación.Las unidades de medición inercial o IMU, son dispositivos que miden aceleración y orientación, que implementados con algún procesador o sistema de cómputos permiten crear un sistema de navegación inercial o INS. El enfoque de esta investigación es crear un sistema de bajo costo que permita fusionar los datos provenientes de los sistemas IMU/GPS mediante un filtro Kalman, esto con la finalidad de aprovechar las características propias de cada sistema y mejorar la precisión del posicionamiento por GPS. Con el uso de este sistema mediante sensores comerciales de bajo costo se hace posible mejorar la precisión del posicionamiento GPS con hasta un 3.03%

MAP entropy estimation: Applications in robust image filtering

We introduce a new approach for image filtering in a Bayesian framework. In this case the probability density function (pdf) of the likelihood function is approximated using the concept of non-parametric or kernel estimation. The method is based on the generalized Gaussian Markov random fields (GGMRF), a class of Markov random fields which are used as prior information into the Bayesian rule, which principal objective is to eliminate those effects caused by the excessive smoothness on the reconstruction process of images which are rich in contours or edges. Accordingly to the hypothesis made for the present work, it is assumed a limited knowledge of the noise pdf, so the idea is to use a non-parametric estimator to estimate such a pdf and then apply the entropy to construct the cost function for the likelihood term. The previous idea leads to the construction of Maximum a posteriori (MAP) robust estimators, since the real systems are always exposed to continuous perturbations of unknown nature. Some promising results of three new MAP entropy estimators (MAPEE) for image filtering are presented, together with some concluding remarks

Riesgos ambientales y su impacto en la mortalidad por insuficiencia renal crónica en el estado de Tlaxcala México

Se analizaron los factores de riesgo ambiental y su impacto en la mortalidad por insuficiencia renal crónica (IRC) en el estado de Tlaxcala. El estudio fue transversal-analítico, se obtuvieron registros de mortalidad por (IRC) del periodo 2012-2013, sitios potencialmente contaminantes y metales pesados en tres fuentes de información. Se observó que el municipio más afectado por mortalidad fue el Carmen Tequexquitla con una tasa de mortalidad de 45.54 por 100,000 habitantes. El municipio con más sitios potencialmente contaminantes fue Huamantla, ubicado en la región oriente. Hubo correlación entre Arsénico y mortalidad por (IRC) con una diferencia significativa de p≤ 0.05. Entre los riesgos ambientales y mortalidad hubo significancia de p≤ 0.05. La asociación entre estas variables corroboró que la presencia de factores de riesgo ambiental, influyen en la mortalidad por (IRC), principalmente en los municipios localizados en la región oriente del estado