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

ERS-2 SAR soil moisture and herbaceous biomass monitoring across a semi-arid transect in Israel

Relationships between radar backscattering coefficient (σº) and environmental parameters of volumetric soil moisture and biomass were empirically investigated in two sites. These sites represent an annual rainfall change from 450 mm to 250 mm across a semiarid transition zone between Mediterranean and arid environments in Israel. A strong linear correlation was found between ground measurements of volumetric soil moisture taken place at the two sites in three different dates and corresponding radar backscatter intensities measured from ERS-2 SAR images. The slope and intercept values of the regression equation are similar to those reported in other regions of the world. Relationships between the radar backscatter and Herbaceous biomass were examined in areas of homogenous vegetation cover. Results show strong linear correlation between Herbaceous biomass measured in the field and the ERS-2 backscatter

Spatial Heterogeneity of Seasonal Grazing Pressure Created by Herd Movement Patterns on Hilly Rangelands Using GPS and GIS

The spatial heterogeneity of grazing pressure on extensive rangelands has management implications (Adler et al., 2001) but it has traditionally been difficult to quantify. Combination of technologies based on GPS (Global Positioning System) and GIS (Geographic Information Systems) is a quantum leap in our ability to address this issue. These tools were used to estimate the spatial heterogeneity of grazing pressure at a farm scale, and examine the relation between local landscape features and local grazing pressure

Lessons for sustainability from the world's most sustainable culture

Sustainable development is one of the key challenges faced by societies today. Yet it is not a new challenge; throughout history, societies have faced the need to live within environmental constraints. Some have done so well, and some poorly. One society which did well for tens of thousands of years is that of Aboriginal Australia. This paper explores some lessons from Aboriginal Australia which have resonance in the modern world and shows that countries which have learned those lessons are in fact more sustainable than those which have not. It thus suggests that there is much that the pantheon of human experience can teach the modern world as it endeavours to create a sustainable future

Growth response of Mediterranean herbaceous swards to inoculation with Azospirillum brasilense

A study was conducted on the effect of the rhizobacterium Azospirillum brasilense strain Cd on the production of herbaceous swards growing at 2 rangeland habitats in Israel. One habitat was the semiarid zone (< 300 mm annual rainfall, calcareous soil on rocky slopes) while the other was a typical Mediterranean zone (approximately-600 mm annual rainfall, karstic rock covered with terra rossa soil). The inoculum was applied in water suspension at a concentration of 109 colony forming units (CFU) ml-1. The effect of inoculation was compared with P-fertilizer application at a rate of 5 g/m2. The same treatments were also applied on potted soil from the 2 sites. The semiarid ecosystem showed a strong response to Azospirillum inoculation, to P-fertilizer and to the combination of these 2 treatments, with aerial biomass production increasing by approximately fourfold in the treatments as compared with the control. The response to inoculation or P-fertilization was similar, with no interaction or additive effect noted for the combined treatment. At the Mediterranean site, the response to inoculation or P-fertilization alone was variable, with only a moderate effect on biomass production as compared with the control; however, the inoculation-fertilization interaction was highly significant and doubled biomass production. In the greenhouse experiment, the response to inoculation or fertilization was significant and the biomass production at the end of the growing season was approximately 50% higher than in the control. At both sites, standing biomass was greater in the treated plots already at early stages of growth, thereby potentially lengthening the effective grazing season. It is suggested that inoculation with Azospirillum brasilense on a commercial scale may offer a means of increasing rangeland production without resorting to costly and ecologically unfavorable fertilizer application.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Use of Tannin-Binding Chemicals to Assay for Tannis and Their Negative Postingestive Effects in Ruminants

Synthetic polymers such as water-soluble polyvinyl pyrrolidone (PVP), water-insoluble polyvinyl polypyrrolidone (PVPP), and water-soluble polyethylene glycol (PEG) contain sufficient oxygen molecules in a chain to form strong hydrogen bonds with the phenolic and hydroxyl groups in tannins. This review deals with the practical uses of tannin-binding agents, particularly PEG, in tannins assays and for determining the negative effects of tannins on feed intake and digestion in ruminants. A gravimetric method to assay tannins by precipitation with PVPP is specific for tannins and does not require standards. The extractability of tannins from plant tissues can be reduced by drying samples at temperatures above 50°C and is dependent on many other factors, such as content and types of plant proteins. Therefore, it is not feasible to recommend a single, optimal protocol for all plant samples. A method to assay tannins which is based on measuring the amount of binding of PEG to plant samples was shown to be simple and accurate. It can also overcome some of these extractability problems. The following biological effects of tannins were investigated in studies where tannin anti-nutritional effects were partially or completely neutralised by varying levels of PEG supplementation. (1) Effects on appetite: the negative effects of tannins on appetite can occur in the short-term (within 20-60 min) and the long-term (days and weeks), Astringency and adverse postingestive influences of tannins on the epithelium of the oral cavity and the foregut cause short-term effects on food intake. Long-term effects can be related to reduction in the concentration of ammonia and volatile fatty acids (VFA) in rumen fluids, which can in turn serve as metabolic cues for deficiency of nitrogen (ammonia), energy (VFA), or both. (2) Effects on digestion: increasing content of tannins in foliage can be associated with an increase in bound protein and with reduced degradation rate of the degradable matter in the rumen, but there is no corresponding increase of the non-degradable fraction. Consequently, organic matter, protein, and cell wall digestibility are inversely related to tannin concentrations. (3) Inducing digestive responses: if a significant amount of tannins reach the duodenum, they may markedly reduce the intestinal activity of pancreatic enzymes (trypsin and amylase) and amino acids absorption from the intestine. Condensed tannins can also reduce the content of fluid and particulate matter in the rumen, accelerate the passage of liquid from the abomasum, and delay the passage of digesta in the intestine. The overall effect is a delay in the passage of fluid and particulate matter throughout the entire gastrointestinal tract. It is hypothesised that these responses are largely the consequence of the interaction of tannins with digestive enzymes and the epithelium lining the digestive tract