Microbial ecology of the rumen: impact on nutrition and the environment. John Wallace

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1 Microbial ecology of the rumen: impact on nutrition and the environment John Wallace

2 R.J. Wallace 2004

3 Rowett picture We bring together extensive capabilities and expertise in nutritional research to pursue cutting edge science aimed at preventing disease and improving health through good nutrition. We aim to provide robust nutritional evidence to guide food and health policies.

4 Microbial ecology of the rumen: impact on nutrition and the environment Introduction to the rumen and its microorganisms Impact of the rumen on nutrition Ruminants and the environment Ruminant products and human health

5 The rumen Cow picture

6 Gut anatomy Colon PIG Ileum Caecum Stomach Jejunum Colon CATTLE AND SHEEP Ileum Stomach (Abomasum) Omasum Caecum Rumen Jejunum Reticulum

7 Rumen ciliate protozoa 100 m

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10 Rumen anaerobic fungi Fungal picture 50 m

11 R.J. Wallace 2004 Fungal picture

12 Rumen bacteria Rowett picture 1 m

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18 Figure 2 M ethanomicrobium mobile (M59142) Proteobacteria Proteobacteria Proteobacteria (OTUs 1-3) Phylum? (OT U 4) Figure 3 Cytophaga-Flexibacter-Bacteroides [CFB] Phylum? (OTU 5) Cytophaga-Flexibacter-Bactero ides Group (OTUs 6-78) Figure 4 Figure 5 High bacterial diversity Figure 6 Low G+C Gram positive Phylum? (OTU 79) Low G+C Gram Positive Bacteria (OTUs ) Figure 7 Figure 8 Figure 9 High G+C Gram positive, Fibrobacter, Spirochaetes, etc Fibrobacter Group (OTU 175) High G+C Gram Positive Bacteria (OTUs 176 &177) Chlamydiales-Verrucimicrobia Group (OTUs 1 78 & 179) Spirochaetes (180)

19 Rumen methanogenic archaea 1 m

20 METHANE VFA ACETATE PROPIONATE BUTYRATE Metabolism in FOOD the rumen BACTERIA Up to 10 6 PROTOZOA?? ANAEROBIC FUNGI 10 8 ARCHAEA per g digesta UNDIGESTED FOOD + MICROORGANISMS

21 Microbial ecology of the rumen: impact on nutrition and the environment Introduction to the rumen and its microorganisms Impact of the rumen on nutrition Ruminants and the environment Ruminant products and human health

22 Ruminococcus flavefaciens Fibre breakdown Fibrobacter succinogenes

23 Protein metabolism Food protein Protein Peptides Amino acids B Microbial protein Undegraded food protein + Microbial protein C Ammonia A A INEFFICIENCES Loss of N Ammonia Urea B C Microbial protein breakdown Amino acid imbalance

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25 Breakdown of microbial protein

26 Rumen-up: influence on protozoal activity in vitro Sample R038 Rate of deg radation ( % ) Concentration (ppm) Control Incubation time (h) Lonicera japonica (Japanese honeysuckle)

27 Methane, ruminants and the environment

28 Methane, ruminants and the environment How much is methane a problem as a greenhouse gas? Is methane from ruminants really a major part of the problem? How does methane formation occur? How can we inhibit methane formation? Encapsulated fumaric acid, efficacy and commercial considerations

29 Greenhouse gases: CO2

30 Methane as a greenhouse gas CH 4 has a global warming potential ( radiative forcing ) 21 times that of CO 2 US Environmental Protection Agency, 2000 Methane contributes approximately 18% to the overall global warming effect

31 Methane as a greenhouse gas t ½ of CH 4 in atmosphere is 12 years Dlugokencky et al., 2003

32 Sources of atmospheric methane 70% of global methane formation is due to man's activities US Environmental Protection Agency, 2001

33 Sources of atmospheric methane Therefore, 20% of global methane formation is due to ruminants US Environmental Protection Agency, 2001

34 Sources of atmospheric methane And so 20% of the 18% = 3.6% of the total radiative forcing is caused by ruminants US Environmental Protection Agency, 2001

35 Ruminants, cars and methane = 164 g CO 2 /km at 19,000 km/year = g CO 2 /year = g CO 2 /year 500 L CH 4 /day = L/year = L/year = 2 16/ g/year = g/year g CO 2 /year g CO 2 /year

36 Ruminants, cars and methane =

37 Ruminants, cars and methane =

38 The New Zealand response Carbon tax As part of the Climate Change Policy Package, released in 2002, the government will be introducing a carbon tax in New Zealand from April 1, Hon. Pete Hodgson, Convener of the Ministerial Group on Climate Change, has announced that the carbon tax will be set at $15 per tonne of CO 2 and has released a consultation paper on the implementation of the tax.

39 Methane production in ruminants 5% 95%

40 Methane production in ruminants Fermentation H 2 + CO 2 Protozoa, fungi, eubacteria Archaea CH 4

41 Inhibition of methane formation Halogenated hydrocarbons Other chemicals Ionophores Acetogenesis Immunisation Defaunation Natural plant extracts Organic acids

42 Decreasing methane emission using organic acids Fermentation [Organic acid + H 2 ] + CO 2 Propionic acid CH 4

43 Organic acids COOH COOH COOH COOH C=O 2H CHOH CH 2H CH 2 CH 2 CH 2 H 2 O CH CH 2 COOH COOH COOH COOH Oxaloacetate Malate Fumarate Succinate Propionate

44 Bakeshure 451 COOH H H COOH Bakeshure 451 Consists of 85% fumaric acid and 15% partially hydrogenated soybean oil

45 Large scale feeding trial in Aberystwyth Methane Production (L/d) Feed Additive Control Bakeshure 451 Fumaric Acid

46 Health implications of biohydrogenation in the rumen LNA LA C18:3 c9 c12 c15 C18:2 c9 c12 LNA LA Saturated fatty acids BIOHYDROGENATION LNA linolenic acid LA linoleic acid unsaturated saturated

47 Health implications of biohydrogenation in the rumen Helps Prevent Heart Disease CLA Helps Prevent Cancer Stimulates Immune Response

48 CLA in foods Sunflower oil Corn oil Olive oil Egg yolk Pork Chicken Fish Beef tallow Cream Butter Cheese Milk Lamb Veal Beef CLA content of fat (mg/g)

49 CLA in foods To provide 10 g of CLA/day requires 3.6 kg cheese

50 Rumen Animal tissues C C C C C 9 12 linoleic acid C C C C C conjugated 2H linoleic acid C C C C C 2H conjugated linoleic acid C C C C C vaccenic 2H acid C C C C C vaccenic acid C C C C C stearic acid

51 Effects on biohydrogenation of unsaturated fatty acids cis C C C C C 9 12 linoleic acid cis trans C C C C C conjugated 2H linoleic acid trans cis C C C C C 2H vaccenic acid Butyrivibrio fibrisolvens Butyrivibrio proteoclasticus 19 samples with activity against B. proteoclasticus but not B. fibrisolvens C C C C C stearic acid

52 Replacing antibiotics in animal feed EC FP6 Promotion of Safe, Healthy Food Chrysanthemum coronarium C. coronarium inhibits last step in biohydrogenation process C. coronarium increases PUFA and CLA content of milk Fatty acid concentration (µg/ml) Vaccenic acid accumulates in the rumen C. coronarium - C. coronarium Time (h)

53 Tracy s Vision of the Future

54 Inhibition of methane formation Intracellular Hydrogen Transfer in Ciliate Protozoa Defaunation Decreases methane formation by 20% CH 4 H 2 H 2 H 2 Acetate Pyruvate Glucose CH4 Methanogens Hydrogenosomes Defaunation technically difficult Adaptation will always be a problem