Microbial feed additives for ruminants

R. J. Wallace, C. J. Newbold

Research output: Chapter in Book/Report/Conference proceedingConference Proceeding (Non-Journal item)

1 Downloads (Pure)

Abstract

Microbial feed additives are used in ruminant feeds for three different purposes. The first is for the same reason that probiotics are used in non-ruminants, namely stabilisation of the intestinal flora; this is applicable only in young, pre-ruminant animals, however, where lactobacilli, enterococci and yeast have been reported to be helpful in preventing diarrhoea and in improving live weight gain in calves and lambs. The second aim in young animals is to enhance the development of the adult rumen microflora, because this stimulates development of rumen structure and accelerates weaning. The same organisms and Aspergillus oryzae fermentation extract appear to achieve this objective, and inoculations with rumen microorganisms have also been found to be effective experimentally. In the adult ruminant, only yeast and fungal cultures have been widely reported to be effective. Responses in meat and milk production are highly variable, with an average response of 7 to 8% in each case to both products. Increased feed intake usually appears to drive the response. In turn, improved intake occurs because of a more rapid breakdown of fibre in the rumen, and an enhanced microbial protein flow from the rumen has been reported. Both types of additive cause a marked increase in the viable count of anaerobes recovered from rumen fluid, but for different reasons. Yeast appears to function by removing traces of oxygen that may be toxic to rumen bacteria: non-respiratory yeasts did not stimulate numbers. In contrast, the mode of action of A. oryzae appears to be associated with its enzyme activity. Neither yeast nor A. oryzae grows to a significant extent in the rumen.
Original languageEnglish
Title of host publicationOld Herborn University Seminar Monograph 8
EditorsR. Fuller, P. J. Heidt, V. Rusch, D. Van Der Waaij
Place of PublicationHERBORN-DILL
PublisherInstitute for Microbiology and Biochemistry
Pages101-125
Number of pages25
ISBN (Print)3-923022-18-2
Publication statusPublished - 1995
Externally publishedYes
Event8th Seminar on Probiotics - Prospects of Use in Opportunistic Infections - HERBON-DILL, Germany
Duration: 27 Jun 1994 → …

Publication series

NameOLD HERBORN UNIVERSITY SEMINAR MONOGRAPH
PublisherINST MICROECOLOGY & BIOCHEM
Volume8

Conference

Conference8th Seminar on Probiotics - Prospects of Use in Opportunistic Infections
Country/TerritoryGermany
CityHERBON-DILL
Period27 Jun 1994 → …

Fingerprint

Dive into the research topics of 'Microbial feed additives for ruminants'. Together they form a unique fingerprint.

Cite this