War of the inner world

Where creatures lurk…

…with delicious terror yet form and function so sublime …

QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.

…creatures beyond our wildest imagining…

Welcome to:Welcome to:

The world of animal The world of animal science…science…

……an inner world an inner world of war…of war…

..dwelling within the humble ruminant

Cellulolytic microbes break down grass

Ruminant digestion: the most advanced in the solar systemFour compartments to ruminants stomach1. 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

protozoan

methanogen

Methane

• Defaunation (sweeping Defaunation (sweeping

protozoa)protozoa)

• Ionophoric antibioticsIonophoric antibiotics

• VaccineVaccine

• Fish-oil, tanninsFish-oil, tannins

Methane inhibition

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

Membrane

Peptidoglycan

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

Improved welfare & production Conserve biodiversity

Reduce antibiotic dependency

Altered rumen fermentation

Less methane

Less ammonia

Bloat control

Acidosis control

QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.Australian

plants

Improveproduct quality

Is Australian flora antimicrobial on selected

species of bacteria?

Where the research is at1. 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

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Silage

Bioremediation of farm waste

• Recycling animal excreta & crop residues

• Agriculture provides 15% of land photosynthetic biomass

• Animal excreta 1.5 billion T/yr (USA)

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.

Cheese