“Metabolisable energy” has been in the news again this week.

Specifically an item about the High Metabolisable Energy ryegrass cultivars that are being developed by Ag Research Scientist Greg Bryan and his team. To help increase productivity AND reduce environmental footprint.

The field trials are going to be done in the U.S.A instead of New Zealand because of our laws around Genetic Modification.

But this post is more about M.E. than promoting the benefits of G.M. I expect you have opinions of your own on that subject.

So here are five surprising things about metabolisable energy.

 

• Its a measurement, a mathematical equation most commonly used to assess the quality and the nutritive value of a feed. It’s all about potential. M.E. says nothing about the nutritional and chemical makeup of the feed.
• Take spring pasture and barley for example. They have similar M.E. values but quite different crude protein and soluble carbohydrate %ages. 
• 0.5 ME can make a difference to intake of Kg DM and therefore ME intake
• Don’t just use ME for pasture analysis…consider the effects of fibre measurements like N.D.F and A.D.F on total Dry Matter intake, bite size and bite rate. 
• Compare pasture silage and maize silage. They have similar M.E. but maize silage is more efficient at putting on weight. Less dry matter required for the same condition score.

I’m looking forward to seeing what actually happens in the field. How the plants cope with the variable weather conditions and grazing pressure.

And also what the cows think of it. Especially the higher percentage [8% compared with the more normal 3-6%] of unsaturated fatty acids in these H.M.E ryegrass cultivars.

Rumen microbes and cows have different needs when it comes to their long chain fatty acids! 

 

 

 

 

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