Tuesday, 21 September 2010

Great Dairy Research in France

So are we being left behind the French?
I've just returned from France with groups from South Wales & Leicestershire.Everytime I go to Brittany & meet the research people from Travarez (like Valerie Brocard) I am very impressed with the quality of Agricultural Science & Research in France.
Farmers in Brittany still have a huge say in the on farm research programs.
Sadly UK grass based dairy farmers have precious little input or say in the research funded by levies.
I fear for the research & the quality of the agricultural science in the UK. At some point this will severely affect the competitiveness of UK grass based dairy farmers.
Valerie introduced us to the new French (EU) feeding standards & system developed by INRA. She has been responsible for a new publication which is a practical guide to dairy herd food (unfortunately in French)
The new INRA system (the Irish are already using it) is a huge step forward in a better understanding of dairy cow nutritional requirements. It takes account of the stage of lactation & better estimates the true value of the feed. It will be an ideal tool to measure N in & N out (as most of the N a cow eats is excreted).

We should be able to identify the ideal supplement to partner good quality grazed pasture & not have a detrimental impact on the environment by using the INRA system.

Photo Scoop of the year....Chris standing in deep dairy clover pasture
"So what did you say this stuff was Nigel?"
Traditionally diets have been formulated to metabolisable energy (ME) but this system overvalues the energy value of poor quality feeds relative to good quality feeds. For this reason a net energy (NE) system is being adopted which will allow better comparisons between the nutritional value of feedstuffs. The NE value of feedstuffs is expressed in terms of FEED UNITS (UF). The system applies two NE values to feedstuffs: (I) UFL for lactating dairy cows, growing beef cattle and sheep and (2) UFV for finishing cattle. In most situations (dairy, beef and sheep) UFL values are used, apart from situations where high levels of concentrates (80% +) are being offered or growth rates over 1.0 kg per day are being achieved. In this situation the UFV value is used.

Barley is the standard feed in this system and all other feeds are given values relative to barley. Standard barley has a net energy value of 1 UFL or 1 UFV per kg as fed. The lower the UFL or UFV value the poorer the energy value of the feed. The NE value of feedstuffs range from 0.45 UFL / kg as fed for good quality straw to 1.05 / kg as fed for maize grain. The UFL value of grass silage (70% DMD) is 0.78 / kg dry matter and that of maize silage (25% starch) is 0.80 / kg dry matter.

Protein is made up of building blocks called amino acids. The true protein value of any feedstuff is best measured by the quantity of these amino acids that are absorbed by the animal, not what the animal consumes. The amino acids that are absorbed by the animal come from two sources: (1) bacteria in the rumen (first stomach) of the cow, which converts energy and nitrogen into bacterial protein (bacterial amino acids) and (2) undegradable protein in the feed, which is not changed in the rumen. The quantity of bacterial amino acids made by the bacteria in the stomach is reliant on a supply of nitrogen and energy. There are potentially two amounts of bacterial protein that the cow can generate - one that relies on there being enough nitrogen in the rumen and one that relies on there being enough energy in the rumen. If there is a limited supply of nitrogen the protein value is called PDIN. If there is a limited supply of energy the protein value is called PDIE. Each feed has two values (PDIN and PDIE).
The lower of the two values is the actual protein value of the feed. Feeds that are high in crude protein tend also to be high in PDIN. Usually in grass silage based diets there is not enough energy to convert all the nitrogen in the diet into bacterial protein. Therefore, the energy supply is limiting and the protein value of grass silage is normally as PDIE.

Much of this is taken from a 2000 Irish Dairy Conference paper presented by Dr Siobhan Kavanagh & Dr John Murphy of Teagasc....the full paper is well worth reading.
If we are being left behind in the UK what are you going to do about it! I think we in the UK should be very concerned at the lack of dairy pasture based research

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