Animal Nutrition and Product Quality Laboratory Manual

Abstract

Animal nutrition is an important factor limiting livestock productivity, and feed costs are considered as the main constraint to raising income from small–scale ruminant production in dry areas. ICARDA’s livestock scientists are searching for alternative feed resources to be included in well balanced diets that can lead to improvements in flock productivity and in meat and milk quality. The nutritional value of proposed low cost diets and their effects on product quality need careful evaluation in the laboratory.

Therefore, ICARDA’s Animal Nutrition Laboratory analyzes feed as well as milk and dairy product quality. This manual covers all analyses conducted in the Animal Nutrition Laboratory at ICARDA, as well as the equipment needed. Special chapters refer to analyses conducted in the newly established laboratories in Libya.

Feed analyses conducted in the laboratory include basic nutritional analyses such as dry matter, crude protein, crude fiber, crude fat, crude ash, minerals and tannins. For these analyses, the laboratory is equipped with Kjeldahl nitrogen analyzer, Soxhlet, Atomic Absorption Spectrophotometer, balances, and centrifuges. The unit also holds donor animals for rumen liquid that is used for two–phase digestibility analysis and Gas Production Tests.

In addition, this manual describes composition and quality analyses of milk and milk derivatives. The laboratory provides analyses for protein, fat, lactose, total solids, acidity, pH, density and conductivity. It also facilitates advanced analyses that use gas chromatography, and HPLC analyzer for detection of organic acids and Volatile Fatty Acids.

One chapter of this manual describes assays to determine the udder health of animals. Mastitis can be determined by either the California Mastitis Test or using somatic cell counter. The blood of sheep can be evaluated for progesterone content using the ELISA assay. The main purpose of this manual is to provide a guide for technicians in the Animal Nutrition Laboratory, and for technicians and researchers from NARS and other collaborators that come to ICARDA for training or collaborative research projects. Furthermore, it informs scientists from ICARDA and outside ICARDA on the services offered by the laboratory.