An in vitro evaluation of BDH casein, lactic casein and formaldehyde treated lactic casein as feeds for ruminants : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Agricultural Science in the University of Canterbury [Lincoln College]

Abstract

Ruminants have developed the capacity to digest plant polysaccharides primarily through the activities of microbial symbionts that inhabit the reticulo-rumen, and to a lesser degree the caecum and colon. These micro organisms require the host animal to provide adequate nitrogen from feedstuffs to meet their requirements for maintenance and growth. In the rumen these nitrogenous compounds are normally degraded to form ultimately ammonia, the volatile fatty acids (acetic, butyric and propionic) and carbon dioxide. Some of these products are absorbed directly through the rumen wall and others are used for microbial growth. As long ago as 1891, Zuntz suggested that rumen micro organisms could synthesize protein from non protein nitrogen and this has been confirmed subsequently by many studies, most of which included urea as the source of non protein nitrogen, but by others involving biuret and ammonium sulphate also (Briggs 1967). In this thesis, the methods used for these studies are described, the results obtained are presented in full and are discussed in relation to previously published related work, and the possible contribution of formaldehyde treated proteins to increasing livestock production in New Zealand is examined.