[Music] heat increment which is the most important parameter we are looking for is then equal to total heat production - fasting reproduction so if we include this heat increment value as hip adduction - fasting reproduction you know previous diagram you can obtain the net energy value which is equivalent now - Emmy - production plus fasting input option then if you consider that ami - heat production is equal to energy gain or energy retention you then get the net energy equivalent to energy gain or energy retention plus fasting reproduction being keeping in mind that energy gain can be growth of an animal in broilers or in growing pigs for instance button can be also exporting energy as milk in the South or eggs as in laying ends so the ratio between net energy and ami is called K or the efficiency of Emmy for net energy this K value if we look for rather constant or rather basic or conventional diets is very similar in all all four types of animals we are dealing with on that figure so about 25% of DME is lost as heat increment which means that the efficiency or the average efficiency for conventional diet for all these animal species is about 75 percent so we could think that the efficiency is not a constant but it's not constant it changed a lot and it changed because you have behind the Emmy different nutrients which are used very differently for net energy I have taken the values obtained in pigs but we could get the same data in poetry indicating that the energy coming from protein is used with an efficiency that is about 60% while the in the coming from starch or from fat are used with efficiency much higher eighty or ninety percent so this means that the inert energy of ami ratio will not be constant for diets and also more importantly for ingredients since this efficiency will vary with the nutrients composition of the diet or the ingredient and so that's the main purpose or the main objective of these videos is to look at the impact of changing the nutrients composition of diets or of ingredients on the net energy value of feet you