Basic principles of nuclear techniques and applications in livestock production

It is known. that many of the advances which have been made in improving the feeding, fertility and health of livestock in developed countries would not have been possible without nuclear tech-niques. Nuclear techniques have been used by scientists to study and understand those biological processes which are responsible for growth, reproduction and disease resistance in animals. Tracer tech-niques based on isotopes have been used for tagging feed constituents, amino acids and other metabolites, whereby their fate .can be fol-lowed within the digestive system and other parts of the body. This forms an integral part of the armoury used by animal nutritionists to establish the nutri-tional value of all the materials potentially available to feed animals. The development and use of highly sensi­tive immunoassay methods, to measure the minute quantities. of reproductive hormones in the blood enables us to determine when. animals are ready- for breeding, check whether animals have been inseminated at the correct time, diagnose pregnancy early enough, and devise corrective measures for reproductive disorders and improve the efficiency of artificial insemination and embryo transfer programmes. Radioisotopic methods have been used to study the immune system. to examine infec­tious agents and how they Stimulate this system, and to develop specific and sensitive methods for development of veterinary vaccines and diagnostic tests.