Validation of Faecal NIRS for Monitoring the Diet of Confined and Grazing Goats

Goats are used for brush control and ecological management of Mediterranean grazing lands. Farmers are willing to cooperate with communities but they need an easy method to evaluate the daily intake of nutrients. A calibration of the chemical attributes of goats\u27 diets was set-up, based on faecal near infrared (NIR) spectra (Landau et al., 2004; Table 1). The accuracy of this methodology was estimated by using the standard error of cross-validation (SECV), which represents the variability in the difference between predicted and reference values when the equation is applied sequentially to subsets of data from the calibration data set. This procedure is justified in situations with calibration samples that are randomly selected from a natural population, but may give over-optimistic results, in particular if data are replicated. The standard error of prediction (SEP) represents the variability in the difference between predicted and reference values when the equation is applied to an external (i.e., not used in any step of the calibration) validation data set. (Naes et al., 2002). The aim of the present study was to test the robustness of predicting dietary CP, in vitro dry matter digestibility (IVDMD), and NDF percentages in goats\u27 diets, using faecal samples totally external to calibrations

Range Dynamic and Sustainability of Mediterranean Grassland

Mediterranean grasslands are a highly diverse and complex ecological resource of considerable economic and environmental importance. Herbaceous plant production that determines the carrying capacity of these grasslands for beef cattle husbandry is not only influenced by climatic factors, habitat characteristics, soil fertility and depth, but also by the stocking density and the nature of the grazing system (Gutman et al., 1999). The yearly Mediterranean pasture cycle is characterized by a temperate, winter-spring growing season and a hot, dormant, summer-autumn dry season. Consequently, pasture growth dynamics result in extremely low biomass availability at the beginning of the rainy season and abundant biomass at the peak of the growing season (Henkin et al., 1998). This is followed by a sharp reduction in amount and quality of the herbaceous vegetation caused by seed dispersal, desiccation, grazing and weathering during the hot and dry summer. Grazing pressure and the consequently highly variable availability and quality of the pasture vegetation determine the nutritional intake of the grazing animals as well the impacts on the growth dynamics of the pasture. High stocking densities interact with forage biomass production, consequently, the amount of standing biomass in the pasture decreases when stocking density increases above a moderate stocking rate. During maturation and seed development, heavy grazing can reduce the potential for re-growth in the following season while at the beginning of the growth season, heavy grazing can inhibit pasture growth to far below that required for adequate animal nutrition. Deferment of heavy stocking at the beginning of the growing season can prevent the fall of pasture production to a low stable equilibrium (Noy-Meir 1975; Gutman et al., 1999). However, with increasingly heavy stocking, deferment must be severely increased to prevent serious reduction of both the growth of the pasture and the nutrition of the grazing herd. The aim of the current study was to identify the productivity and sustainability of Mediterranean grassland under different stocking densities and timing of the grazing on a predominantly annual Mediterranean pasture. The present analysis is based on a long-term experiment (1994 - 2014)

The function of "desert kites" - hunting or livestock husbandry ?

Recently it was suggested that "desert kites" - man-made structures built, almost certainly, for hunting - were also used for the husbandry of semi-domesticated animals. The following response will examine this new notion and its suitability for interpreting the possible functioning of these archaeological structures. For both biological and anthropological reasons we do not accept the new explanation for the function of the "desert kites ".Il fut suggéré récemment que les « desert kites » - des structures construites selon toute vraisemblance, pour la chasse - avaient aussi servi pour gérer des troupeaux semi-domestiqués. Dans cette réponse, les arguments avancés pour justifier cette hypothèse sont examinés. Pour des raisons à la fois biologiques et anthropologiques, il nous est apparu impossible de la retenir.Rosen Baruch, Perevolotsky Avi. The function of "desert kites" - hunting or livestock husbandry ?. In: Paléorient, 1998, vol. 24, n°1. pp. 107-111

Ecological sustainability in rangelands: the contribution of remote sensing

Rangelands in temperate areas provide food to herds of domesticated animals and, therefore, provide the infrastructure for two major industries: (a) the meat industry that feeds large populations around the globe; and (b) the wool industry that uses fibre from sheep. In the semiarid zone, rangelands have a socio-economic role as they support the economy and culture of pastoral societies. However, despite their importance, rangelands are under constant threat due to encroachment by humans and invasion by noxious plants, due to degradation and erosion processes and due to drought effects. Remote sensing can be used to identify and monitor the threats to ecological processes in rangelands and, thus, to their ecological sustainability. This article provides a review of the scientific literature on the remote sensing of rangelands and discusses recent developments with respect to mapping thematic classes of vegetation and vegetative cover, mapping biophysical properties such as primary production, and monitoring land-use changes, including those driven by anthropogenically enhanced processes such as soil erosion. In the light of the reviewed studies, we expect that future research on monitoring rangeland sustainability with remote sensing will focus on hyperspectral measurements of the spectra of rangeland plant species, on lidar measurements of canopy height, and on synthetic aperture radar for biomass assessment. In the long-term, more predictive (or at least heuristic) modelling of degradation scenarios due to erosion, invasion of noxious species, and land-use transformations can be anticipated