Agricultural Wastes最新文献

The purpose of this study was to explore the possibility of utilizing portions of hog manure for animal feed, based on proximal chemical, microbiological, protein quality and cooper toxicity testing. Solids recovered from hog manure (RS) were mixed in levels of substitutions of 15, 30, 45 and 60% with commercial cattle feed (CF). The protein content of the mixtures varied little. The in vitro digestibility of the protein decreased as the RS content was increased, and was 87·8% for a substitution level of 0% RS and 66% for a 60% substitution.

The quality of the protein was evaluated by the Protein Efficiency Ratio (PER) and Net Protein Utilization (NOU) assigning maximum values of 1·24 and 24·12, respectively, to a 30% SR and 70% CF (commercial feed).mixture. This mixture showed an adequate amino acid profile.

The microbiological analysis of the RS showed negative results for the pathogenic microorganisms studied. Total counts of microorganisms, fungi, yeast and most probable number of organisms were similar to those of commercial cattle feed. The copper content of the RS was 170·35 ppm.

Biological fermentation of whole fish, viscera and heads using Lactobacillus plantarum was evaluated and the minimum lactose necessary for a successful fermentation under pilot conditions was found to be 5%. Preheating the fish before fermentation decreased the amount of soluble nitrogen substances both before and after fermentation. The relationships between lactic acid bacteria growth, yeast and mold growth and pH indicated that it may be necessary to add an antimycotic agent to achieve and maintain sufficiently low pH values for successful fermentation and storage. Fermentation temperatures of 25 and 35°C and inoculum size of 10³ organisms g⁻¹ of fish produced successful fermentations.

Cassava leaf meal (CLM), prepared from leaves remaining after the harvest of cassava roots, contained (dry basis): 20·1% crude protein, 30·3% acid detergent fibre, 4·6 Mcal kg⁻¹ gross energy, 1·16% calcium, 0·39 phosphorus and 84·0 mg kg⁻¹ hydrocyanic acid. It was also found to be a good source of essential amino acids, except for methionine, and of trace minerals.

Two feeding trials were conducted to study the effects of feeding CLM on the growth of rabbits. In each trial, 24 six-weeks-old crossbred rabbits were individually fed diets containing 0%, 20% and 40% CLM substituted for equal amounts of coconut oilcake in a 16% protein control diet. The results suggest that CLM could be used up to the 40% level in growing rabbit diets without any adverse effects on growth performance or carcass characteristics.

Munj (Succharum munja) plants, available in abundance in India, can be used to make rope. A stripper for the separation of the fibrous leaves from the stalks and a beater to make the leaves suitable for rope preparation were developed. A locally available rope making machine was evaluated and the economics of rope making assessed. The technology developed has good potential for adoption at the village level with attractive returns.

This paper describes the process of pickling slaughterhouse by-products with inorganic acids in order to prevent spoilage and improve processing economics. The addition of sulfuric acid (3% by weight of the material to be pickled) was found to prevent the rapid onset of putrefactive changes and did not adversely affect crude protein composition. The pickled products have potential use as a source of protein in terrestrial animal feeds. Due to their low residual acidity and low water solubility, the pickled products also have potential use in aquatic animal diets.

An original analytical model of the biochemical behaviour of an anaerobic digester and its thermal balance under steady-state conditions is presented and described. It is based on the fundamental equations for hydrolysis, acidogenesis and methanogenesis and determined by several kinetic parameters. The thermal balance is investigated to define the optimum working temperature in relation to several operating parameters (outdoor temperature, geometry, insulation, etc.), from the maximum net energy content and the energy used to heat the fermenting system, bearing in mind the strongly temperature-dependent biogas productivity of the mesophilic bacteria.