[Music] so good morning good afternoon and good evening to everybody uh or to all people connected uh also i would thank the beginning of this webinar the adiso organization for this webinar and also for the short educated videos that were published or presented two or three months ago so if you haven't seen these videos yet i encourage you to look at them so anyway i think as indicated by apparently this webinar is mainly uh composed of question and answers so don't hesitate for that but if just before starting i would give a few slides in order to summarize what was given and the key points about net energy uh in poultry and in pigs so as you can see on that first slide i think uh when we talk about energy utilization we start from gross energy and then we move to d e and to me and then to net energy i will not detail all these steps but i will focus mainly today on i think the question will answer all these points about the last part of this diagram uh talking about uh k which is the relation between net energy and amy about heat increment and about the calculation and the measurement of net energy which is the addition of energy gain plus fasting reproduction so next slide how do we measure energy gain i think there are different techniques or different methods for doing that i think uh converting slowdown methods and so on but i think nowadays i think most techniques are based on the calorimetry and more precisely the indirect which we made so what do we do for calculating energy gain in the indirect current method we obtain energy gain as the difference between m intake by the animals minus their reproduction but for measuring this enemy intake and this reproduction there are some points to be careful first we are talking about diets and so the animal should be adapted to the diet i have put five to ten days and i think that's a minimum to adapt an animal to a new diet so for measuring for using the indirect kermit method we use so-called respiration chambers which is a closed room and i think it's important to adapt the animal to this new environment and that should be at least for one day further afterwards we have you have to measure the heat production per se and i think you need at least two or three days or even five days and that should be done under very standardized and representative conditions and that's very important for interpreting the data afterwards so be careful for instance if you see net energy measurements connected over only one day even less than one day i think you should be very careful in the interpretation of the data so at the same time you measure the animal in the restaurant samples you can measure the intake and at the end net energy is calculated as energy gain plus fasting reproduction so in the short videos fasting reproduction was fully detailed and described how to obtain these values so what i want to insist at that stage is that measuring net energy is rather complex i think you need equipment you need to calibrate you need very uh routine methods and that's not easy that's time consuming that's a long term response i mean you don't get the response only one day you need weeks and even months for measurements and that's expensive and so on and so on so i consider that measuring net energy is more research activity so next slide i will insist on another point which is important and i will talk about that today i think during the questions that's what do we listen or what do we understand by net energy system i think a net energy system is equivalent to a net index one net energy equation clearly net energy in practical terms is not measured it is calculated from an equation these equations can be obtained according to different methods but usually these equations come from the combination of net energy measurements that are conducted on very well balanced and variable diets under very controlled standardized and representative conditions so the videos explain that a little bit so which type of models are we using for calculating these equations usually we use linear regression models where net energy is calculated as a function of the amount of digital nutrients in the feed or it is a function of the de or dme content plus some correction factors or it can even be net energy as a function of some indirect measurements such as individual or infrared indicators so clearly net energy and we talked about that today is calculated from an equation next slide so what's the the situation for the two groups of animals we have to deal with today i think for pigs the net energy prediction equations they are available they are validated or they have been validated they are quite robust and as a consequence they are today i think widely used in feeding tables and in the field industries all over the world for poetry the situation is a bit different i think there are some equations available but these equations have not been fully validated and one consequence of that but there are also other reasons is that net energy is not much is not yet used in practice so that means that in order to be more convincing about using net energy in poetry we should do some additional research next slide for illustrating what's the difference between pigs and broilers so on that table i have put some uh typical ingredients for soy oil corn wheat and soybean meal you know about the chemical conversion of these ingredients which are totally different what you can see first is that the ratio between net energy and me is different according to this critical condition of the ingredients for oil or for full fat sources i mean the efficiency is quite high ninety percent uh for the sugars is somewhere in the middle eighty percent and for seven meal uh it is much lower about 60 percent but i showed that slide mainly to illustrate or to focus on the comparison between pigs and broilers i mean these values were calculated from two sets of equations one published by inra for pigs and one published by the university of new england in australia for broilers you can see that pigs and broilers are behaving very similarly in terms of efficiency of me4 net energy so nowadays we are using net energy very routinely for pigs so why should we uh shouldn't we use also net energy for boilers in the future according to such data so the last slides for this introduction uh will uh show what should be done in practice for the feed industry uh organization uh so as i said before net energy value of diets and of ingredients is calculated from an equation or a system so the important point there is to decide on one equation or one system and preferably one system that has been validated on diodes and learning ingredients so uh i think i will stress also on one point which is very important is that uh some religious organizations some groups in the world are measuring any net uh value of ingredients in my opinion i think there is no need to measure net energy of ingredients but in the case of ingredients what is important is to get d e or m e values or digital nutrients which are very quite reliable which have been updated and so on in order to calculate or to include these values afterwards in the net energy equation the last point before uh moving to the question is that net energy values from different origins i mean different equations different labs and so on cannot be combined you should be very careful about that and so again you need to decide on one system or one equation in order to calculate and to implement net energy in your company so that's all for the introduction that's a summary of the short videos we presented two or three months ago and so now i think we can move to uh questions and we try with pierre and pierre andre to answer all of them or most of them you