Four species of African giant land snails (Archachatina marginata (ovum) Pfeiffer, Archachatina marginata (saturalis) Philippi, Achatina achatina and Limicolaria spp.) were assessed for their proximate and mineral compositions aimed at establishing their nutritive values on wet weight basis. Analysis of muscle revealed that composition of crude protein varied from 18.66%±0.57% in Limicolaria spp. and 20.56%±0.05% in Archachatina marginata (ovum) Pfeiffer; moisture content was 76.56%±0.04% in Archachatina marginata (ovum) Pfeiffer and 78.68%±0.68% in Limicolaria spp. and ash was 1.34%±0.02% in Achatina achatina and 1.44%±0.01% in Archachatina marginata (ovum) Pfeiffer. These values were statistically different from each other (P<0.05). Carbohydrate and fat content were generally low. Crude fibre was not detected in any of the species.The concentrations of zinc, iron, manganese, magnesium, calcium, phosphorus, sulphur, potassium and sodium in the flesh of the snails were determined. Values of iron, magnesium, calcium, phosphorus, potassium and sodium were consistently high while cobalt, copper and lead were not detected. Snails complement the required trace and minor elements needed for proper growth and development in human being, so it is recommended for regular consumption.

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Computer models must be thoroughly evaluated before being used for decision-making. Th e objective of this paper is to evaluate the ability of a newly developed wheat grazing model to predict fall-winter forage and winter wheat (Triticum aestivum L.) grain yield as well as daily weight gains of steer (Bos taurus) grazing on wheat pasture in Oklahoma. Experimental data of three independent fi eld studies were used. Th e fi rst was a variety trial in which fall-winter forage and grain yields were harvested. Th e second was a planting date experiment in which forage in the fall-winter period and grain yields were harvested. Th e third was a steer grazing experiment in which standing wheat biomass and steer weight gain were monitored. For the variety trials, the model effi ciency (ME), which refl ects how well model predictions match measured data (1 means a perfect match), was 0.102 for fallwinter forage prediction and 0.367 for grain yield. For the planting date experiment, the ME was 0.615 for predicting fall-winter forage yields and 0.409 for grain yields when a root downward extension rate of 20 mm d -1 was used. In the steer grazing experiment, the relationship between average daily weight gain and forage allowance was adequately represented by the model. For the total steer weight gains in a wide range of stocking rates and grazing durations, the ME was 0.616. Overall results show that the model, if well calibrated, has the potential to predict fall-winter forage and grain yields as well as mean daily weight gain per steer.

Elemental analysis of archaeological bones, particularly for elements such as fluorine, strontium, and zinc, has been carried out for many years, with the aim of determining their age or relating their composition to diet. Bone samples are commonly dry ashed before analysis to remove organic material and render them more readily soluble. In this study, the recoveries of strontium, zinc, and nine other elements are reported for a range of ashing times and temperatures. Recoveries of sodium, potassium, fluorine, chlorine, bromine, and zinc are significantly affected by ashing under some conditions, but recoveries of strontium, calcium, magnesium, and manganese are not.

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