methane and feed

H2 accumulation

impaired digestion

acetic acid

h2 source

proprionic acid

h2 sink

butyric acid

h2 source

acids in the rumen

acetic, propionic, butyric acid

methane: relative to co2

short term effect, so that the effect is higher on the low term

methan half year life

12 years, so reduce methane production then cleraeance rate from atmosphere

nutritional strategies to decrease enteric methane

-        Intake and diet composition

o   Level of intake

o   Roughage quality / nutritive value

o   Level of starch, fibre, fat etc

-        Specific methane inhibitors

impact on methane

increase feed intake level

optimal forage maturity

tanniferous forages

decrease forage: concentrate ratio

oils and fats

nitrate

essential oils

3no

seawead

Increasing feeding level

-        Directs nutrients to milk or weight gain

o   Inrease absoulate methane emission )g/head/day) + 18 degrees Celsius

o   Decrease methane yield (g/kg feed): -8% (-4 to -12%)

o   Decrease methane intensity (g/kg product): -17% (-9 to -23%) (milk)

-        How to increase feed intake?

o   High quality management (hygiene, feeding frequency etc)

o   Avoid situations insufficient forage

o   Deitary deficiencyes (lack of protein, minerals, etc)

-        Trade-off

o   Decreased fibre digestibility, due to the greater feed intake level, retention time has an effect on the fibre

decreasing grass maturity

-        The key for thi is high quality grass, more mature, more fibre

-        Yung grass, better digestibile, shift fermentation process in the rumen to more probiotics, lower hydrogen, more digestible nutrients, more milk, per unit of milk lower methane

-        Shifts rumen fermentation and increases production (milk/growth)

-        Increse methane emission (g/head/day): +7% (1-17%)

-        Decrease methane yield (g/kg feed) -4% (-1 to -8%)

-        Decrease methane intensity (g/kg product): -13% (-7 - -18%) (milk)

-        Good applicability

-        Trade offs:

o   Increased nitrogen (N) excretion

o   More intense management

increasing harvest maturity of whole plant maize silage

-        At the highest maturity, more starch, more slowly degradblae starch, methane emissions are lower

-        Inclusion of taniferous forages, opzoeekn

-        - tannis are plant secondary compounds rich in phenols

-        Inhibit rumen methanogens and protozoa; shift rumen fermantion

-        Decrease absolute methane mission

-        Decrese methane yield

-        Decrease methane hield

-        Promising species include buschclover, birdsfoot trefoil, leucaena

-        Commercial tanning etracts available

concentrate ratio

-        Increase concentrate, may increase feed-food competition

oil/fats

negative effects

3nop and mcr

-        Huge effects, varible effects

-        Less efficient with high fibre high fat

-        Depends on type of diet