Unseen Challenges in Balancing Fat in Poultry Nutrition

. Dr Pooja Bhardwaj, my compliments for the quality of the reviewed subject. Taking the opportunity of the matter, I would like to make a consideration about the use of fat in the diet of chickens exposed to high temperature environment. One of the fundamentals of nutrition is that increasing the concentration of dietary energy leads to a reduction in voluntary food consumption by birds. If at high temperature there is a natural reduction in consumption, what would be the basis for increasing its concentration under these conditions. It is that in high temperature conditions, different from those of the thermoneutral, for the voluntary food intake by the birds to be reduced, it is necessary that the increase in energy be much more expressive. Thus revealing that the physiology of birds is altered by temperature. Thus, it can be deduced that the negative influence of high temperature on the performance of birds is not justified simply by reducing food consumption. The advantage of using fat as an energy source in these conditions is actually its lower caloric increase

In addition to what Professor Juarez said, that the addition of fat contributes to reduced heat production because it has a lower heat increment than protein or carbohydrates, the addition of fat increases the energy value of the other feed ingredients in the diet. It has also been shown that fat decreases the rate of food passage in the GI tract and thus increase nutrient utilization. Because of all these findings, the addition of fat is beneficial at high temperatures.

Dear Dr. Bhardwaj. It's an interesting review on potential fat benefits in poultry diets. I would like to raise some points here for further discussion, with particular regard to broilers. One is that is important to separate the impact of increasing fat addition with or without increasing energy in the diet. If we increase fat and energy, we will obtain fatter broilers with lower breast yield. In the case where broilers are cut up this will have a negative impact on sales revenues, not to mention potential complaints from consumers. If we increase energy and keep ideal protein to energy ratio the same to avoid it, then the benefit of increasing fat on heat generation is lost because protein has the opposite effect. On the other hand, the expected benefits on performances in broiler under heat stress might not be what we generally expect. For that, I refer to the meta-analysis published by Cerrate and Waldroup in 2010 in International Journal of Poultry Science (Maximum Profit Feed Formulation of broilers. 3. Interaction Between Energy Content and Temperature). They saw that responses to increases in energy were smaller for broilers under heat stress, especially for body weight gain (close to 50% of birds under thermoneutral conditions). Also to reinforce Dr. Bhardwaj mention to the fact that when added in pelleted feeds (especially if added in the mixer) the negative impact on pellet quality can negate the expected benefits on weight gain and decrease the improvement in feed conversion. So, from an economical perspective, these negative points have to be considered in the calculations of expected benefit. Thank you.