Interview with Jean Noblet, international monogastrics nutrition consultant
During the 10th International LEVUCELL SB technical meeting on June 19, 2018, in Münster, Germany, Jean Noblet, presented “Energy utilization and heat production in pigs: application to reproductive sows.” We took this opportunity to ask him a few questions about the net energy system for swine.
One of the most important outcomes of your research in swine was the development of the Net Energy System.What are the advantages of this system?
"The main advantage is that we are getting the best estimate of the "true" energy value of the feed."
What kind of tools did you use for the development of the system?
"We developed this program in the late 80s, early 90s, during 10 years. Its originality is that we were able to measure the digestible energy (DE), metabolisable energy (ME) and net energy (NE) value of around 100 diets! All the feeds were characterized and the animals’ response was measured thanks to respiratory chambers: this is very complex equipment and very few exist in the world."
What is the expansion of the Net Energy System?
"Thanks to the number of feeds measured, we have been able to publish a robust equation, but we are not “the only one". There are different schools. Some don’t accept NE system and keep using DE or ME, and other net energy measurements have been proposed or adapted. However, most people in the world are still referring to the original equation."
Does the Net Energy System make any differentiation between different types of animals?
"There may be some genetic effects, but I think most of the differences are linked to the age and stage of the animal. When pigs are getting older and heavier, they have better energy digestion. DE and ME are related to the age and body weight of the pigs, but not NE. NE equation is quite robust and can be used at any stage of production."
Are there any feed factors that make the application of the Net Energy System even more precise?
"NE is by definition predicted from DE or ME content. Feed parameters such as chemical composition or nature of fibers, particle size, etc., are already taken into account in the DE or ME value. What could be added are some functional effects that cannot be taken into account by chemical analysis, such as the effects of probiotics or enzymes. They could affect DE value and, as a result, the NE."