Clinical trial of efficacy of ivermectin pour‐on against gastrointestinal parasitic nematodes in silvopasturing horses

The aim of this study was to assess, by a clinical trial, the efficacy of an ivermectin‐based pour‐on treatment against gastrointestinal parasitic nematodes in naturally infected horses using 2 groups of mature indigenous Pura Raza Galega grazing mares. Faecal and blood samples were collected individually over a 21 week period. Faeces were analysed by the coprological flotation, sedimentation and migration techniques. Changes in circulating blood cells were monitored over the study period. The administration of the ivermectin suppressed the eggelimination of ascarids and pinworms throughout the study and no strongyle‐eggs were observed in the treatment group between the 3rd and 10th weeks. The numbers of red cells increased significantly after the anthelmintic therapy, and a statistical reduction in circulating leucocytes was recorded. No side effects were observed. The pour‐on ivermectin formulation was highly successful against gastrointestinal nematodes and appears to be a useful therapeutic routine for large groups of horses.     

New algebraic formulations of evapotranspiration extracted from gene-expression programming in the tropical seasonally dry regions of West Africa

Within hydrological nonlinear complex functions, taking only few parameters into the modeling process is still a challenging task. The present paper has for objective to investigate for the first time the predictive ability of the Gene-expression Programming (GEP) for modeling reference evapotranspiration (ETo) using routing weather data from the tropical seasonally dry regions of West Africa in Burkina Faso. The regions under study are located in three agro-climatic zones, Bobo Dioulasso in the Guinea Savanna zone, and Dédougou and Fada N’Gourma in the Sudan zone, and Ouagadougou in the Sudano-Sahelian Savanna zone. Several meteorological data combinations are used as inputs to the GEP to estimate ETo, and their performances are evaluated using R ² and RMSE. Statistically, it was found that GEP can be an alternative to the conventional methods, and its accuracy improves significantly up to R ² (0.979) and RMSE(0.108) when critical variables are taking into account in the model. The results revealed that GEP model is fairly a promising approach with the advantage to provide successfully simple algebraic formulas ease to use without recourse to the full set of meteorological data requirement for accurately estimate ETo in Sub-Saharan Africa regions.     

Early mortality of lambs in African traditional livestock production systems

Early mortality of lambs is a major constraint on total productivity. In 6 different environments the early death rate varied from 12 to 30% of all lambs born. Cause of death differed among systems but only a proportion could definitely be ascribed to infectious disease: nutrition, management and other environmental factors also contribute to the mortality rate. Mortality can be reduced by isolating solutions due to any of these factors but best results (lowest death rates) would be obtained by an integrated package containing elements of all these aspects.     

Effects of the aqueous extracts of Zygophyllum fabago on the growth of Fusarium oxyosporum f. sp. melonis and Pythium aphanidermatum

In this study, the effects of aqueous extracts from Zygophyllum fabago L. on two plant phytopathogenic fungal species (namely, Fusarium oxyosporum f. sp. melonis and Pythium aphanidermatum) were studied under laboratory conditions. The plant extracts (10% w/v) were prepared by using deionized water and fresh tissues. Dilutions (2, 4, 6, and 8% w/v) were obtained to test their effect on the mycelial growth of the phytopathogenic species. Additionally, the recovery of the fungi after their exposure to the Z. fabago extract was analyzed. The plant extracts inhibited the growth of F. oxyosporum and P. aphanidermatum (the maximum mean inhibition that was recorded with the 10% w/v extracts was 42.9% and 85.3%, respectively). A second series of experiments demonstrated the existence of residual effects in both species. The amount of residual inhibition by the 10% w/v extracts was 28.6% in F. oxyosporum and 53.8% in P. aphanidermatum. A dose–response was clearly observed in P. aphanidermatum, while an increase in extract concentration was not associated with a significantly greater reduction in the growth of F. oxyosporum. These findings give insights into the potential of Z. fabago as a growth inhibitor of F. oxyosporum and P. aphanidermatum, thus suggesting an interesting potential role for this common weed as a source of natural fungicides.     

High Genetic Diversity Among Strains of Fusarium oxysporum f. sp. vasinfectum from Cotton in Ivory Coast

ABSTRACT Seventeen isolates of Fusarium oxysporum f. sp. vasinfectum from the Ivory Coast were characterized using vegetative compatibility group (VCG), restriction fragment length polymorphism of the ribosomal inter-genic spacer region (IGS), and mating type (MAT) idiomorph, and compared with a worldwide collection of the pathogen containing all available reference strains. Some of the isolates were identical to known reference strains for all three traits, whereas others had previously unknown varieties of IGS and (possibly) VCG. One or the other MAT idiomorph was present in each of the new isolates and the reference strains. The new isolates and reference strains were grouped based upon the three traits. Strains from the Ivory Coast were found in 7 of 11 groups detected, suggesting multiple sources for Fusarium wilt in the country. Despite the presence of both MAT idiomorphs among isolates, no evidence for recombination was found.     

Andosols developed from non-volcanic materials in Galicia, NW Spain

A set of well-drained soils in Galicia, formed from gabbros, amphibolites and schists, with udic moisture and mesic temperature regimes, are studied. All but one of the surface horizons show an'exchange complex dominated by amorphous material'(ECDAM); consequently, most soils are classified as Andosols (FAO) or as different subgroups of Dystrandepts (Soil Taxonomy). The soils on gabbros and amphibolites frequently have'andic properties'so, following the ICOMAND proposals, five of the 12 soils studied may be characterized as Andisols. Many of the five soils have properties comparable to those of soils from volcanic areas, especially to those called'non-allophanic Andosols', which have an abundance of active-Al, mainly in the form of Al-humus complexes.     

Recalibrating plant water status of winter wheat based on nitrogen nutrition index using thermal images

Precision Agriculture - Accurate and timely assessment of crop water status is imperative for in-season irrigation scheduling in crop production. The canopy water stress index and water deficit...