Impact of Post Peak Daily Metabolizable Energy Intake on Performance of Broiler Breeder Hens

One hundred ninety two broiler breeder hens, from 40 to 49 weeks of age, were utilized in a precision feeding study for determining the hens’ energy requirement. Treatments were daily feed allotments containing metabolizable Energy Requirement (ER) estimated by empirical model, ER minus 10 (ER‒10), plus 10 (ER), and plus 20 kcal hen-1 d-1 (ER). Four levels of Metabolizable Energy Intake (MEI) were made by adding 0, 1.2, 2.4 and 3.6 grams corn oil, over the top of daily feed allotment. All birds consumed the same amount of diet, and were provided the same intake of nutrients, except energy. Hens with weight gain of 3.5 g per day had the maximum reproductive performance. Ovary weights were lower in ER-10 hens. This difference was also reflected in Small Yellow Follicle (SYF), and Large Yellow Follicle (LYF) numbers, in which the ER-10 hens had fewer SYF (7.6) and LYF (1.1). Hens that received 462.7 kcal d-1 (ER), produced 4.04 eggs more than those that received 452.7 kcal d-1 (ER‒10). However, addition of extra 10 and 20 kcal (ER, ER) on daily MEI had no beneficial effect on egg production. Using the linear broken line model, the ME requirements for egg production and hatchability were estimated at 458.5, and 456.2 kcal hen-1 d-1, respectively. Comparing the current estimated requirement value with earlier reports revealed that broiler breeder hens need more energy in a commercial house than those kept in an experimental house in the cage or pen. In conclusion, during post peak period with average 458.5 kcal MEI, 5 kcal hen-1 d-1 more than Ross 308 recommendation can improve broiler breeder hens’ performance.