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War of the inner world Where creatures lurk… …with delicious terror yet form and function so sublime … …creatures beyond our wildest imagining… Quick Time™ and a TIFF ( Uncompr ess ed) decompres sor ar e needed to s ee this pictur e. Welcome to: The world of animal science… …an inner world of war… ..dwelling within the humble ruminant Cellulolytic microbes break down grass Ruminant digestion: the most advanced in the solar system Four compartments to ruminants stomach 1. Rumen (pH 7) - fermentation vat - host to microbes 2. Reticulum - mixes, filters large particles 3. Omasum - removes water 4. Abomasum (true stomach) - pH 2 - same as human stomach Rumen Reticulum Omasum Abomasum (true stomach) Rumen function: Mutualism • Bugs supply VFA and microbial protein • Byproducts: CO2, CH4 and NH4+ • Animal supplies 5 star accommodation Rumen bacteria • World population = 6.5 billion = 6.5 x 109 = 6 500 000 000 • Bacteria in 1 drop of rumen fluid = 1 x 1011 = 100 000 000 000 Rumen bacteria • Cellulolytic - digest cellulose • Amylolytic - digest starch • Proteolytic - digest protein • Acid utilising The big issues of animal production • Methane production • Antibiotics in feed Methane protozoan methanogen Methane inhibition • Defaunation (sweeping protozoa) • Ionophoric antibiotics • Vaccine • Fish-oil, tannins How much antibiotics do we use? • Total use: 700 Tonnes per year • Humans: 250 Tonnes per year • Veterinary: 50 Tonnes per year • Stock feed: 400 Tonnes per year JETACAR report, 1999 Gram + Gram - Peptidoglycan Peptidoglycan Membrane Membrane Periplasm Lipopolysacharide & protein Antibiotics as growth promoters • Voluntary European ban in 2005 • USA & Australia expected to follow • Need to find safe alternatives Reduce pollution Less methane Improve product quality Less ammonia Altered rumen fermentation Bloat control Reduce antibiotic dependency Australian plants Q uic kT ime™ and a T IFF (LZW) decompres sor ar e needed to s ee this picture. Acidosis control Improved welfare & production Conserve biodiversity Is Australian flora antimicrobial on selected species of bacteria? Where the research is at 1. Screening Australian plants in vitro 2. Inhibition on pure cultures 3. Molecular quantification -DGGE, Real-time PCR 4. In vivo feed trial Questions for the modern scientist Can we; • Improve rumen efficiency? • Reduce environmental pollutants? • Reduce dependence on antibiotics? • Maintain consumer-safe production? Can we understand the war of the inner world? • • • • • • Bioenergetics of animal production Microbiology Underlying chemistry Molecular quantification Application of science Careers in animal production Why are bugs important in animal production? • • • • • • Rumen fermentation Manufacturing of dairy products Soil Health Disease Silage Bioremediaton of farm waste Silage QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Bioremediation of farm waste • Recycling animal excreta & crop residues • Agriculture provides 15% of land photosynthetic biomass • Animal excreta 1.5 billion T/yr (USA) Cheese QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see t his picture.