Impact of growth curve and dietary energy-to-protein ratio on productive performance of broiler breeders

Abstract

The impact of growth curve ( GC ) and dietary energy-to-protein ratio on productive performance of broiler breeder females was investigated from 0 to 60 wk of age. One-day-old pullets (n = 1,536) were randomly allotted to 24 pens according to a 2 × 4 factorial arrangement, with 2 GC (standard growth curve = SGC or elevated growth curve = EGC , +15%) and 4 diets, differing in energy-to-protein ratio (96%, 100%, 104%, or 108% AME n ). Feed allocation per treatment was adapted weekly based on the desired GC, meaning that breeders fed the different diets within each GC were fed according to a paired-gain strategy. Linear and quadratic contrasts for energy-to-protein ratio for each GC were evaluated. Elevated growth curve breeders had an earlier sexual maturity (∆ = 4.1 d) than SGC breeders. Egg weight was higher for EGC breeders (∆ = 2.3 g) than for SGC breeders over the whole laying phase (22–60 wk). No differences between EGC and SGC breeders were observed on settable egg production. An increase in dietary energy-to-protein, at a similar BW, led to a linear increase in age at sexual maturity (β = 0.14 d/% AME n ). From 22 to 40 wk of age, an increase in dietary energy-to-protein ratio led to a linear decrease in egg weight (β = -0.06 g/% AME n ), regardless of GC. An interaction between GC and dietary energy-to-protein ratio was observed on settable egg production in this phase. An increase in dietary energy-to-protein ratio led to a linear decrease on settable egg production, which was more profound in EGC breeders (β = -0.70 eggs/% AME n ) than in SGC breeders (β = -0.19 eggs/% AME n ). From 41 to 60 wk of age, an interaction between GC and dietary energy-to-protein ratio was observed on egg weight. In the EGC, an increase in dietary energy-to-protein ratio led to a linear decrease in egg weight (β = -0.13 g/% AME n ), whereas in the SGC, a linear increase in egg weight was observed (β = 0.03 g/% AME n ). From 41 to 60 wk of age, no differences between diets were observed on settable egg production. It can be concluded that a higher GC of breeders has beneficial effects on egg weight, while maintaining settable egg production. Feeding breeders a lower dietary energy-to-protein ratio stimulated productive performance of broiler breeder hens, mainly during the first phase of lay. This effect was more profound when breeders were fed according to a higher GC.

Interaction Effect of Vitamin E-selenium Supplementation and Metabolic Energy on Reproductive Performance of Joper Breeders

“…surplus energy in the body is stored as body fat mass as a precursor in the synthesis of lipoproteins in egg yolk. The ME also plays a role in the absorption of vitamin E-selenium in the body (Heijmans et al 2021;Ren et al 2021). Vitamin E is a natural antioxidant to reduce ROS in egg yolk by reducing lipid peROSidation and oxidation.…”

“…Surplus energy in the body is stored as body fat mass. Body fat mass plays a role in regulating sexual maturity, egg production, egg yolk composition, maximizing the absorption of vitamin E and reproductive hormone precursors (Heijmans et al 2021;Ren et al 2021). Research is needed to determine the interaction between ME and the right dose of vitamin E-selenium supplementation in improving hatching egg quality because there is very little information available..…”

Impact of growth curve and dietary energy-to-protein ratio of broiler breeders on egg quality and egg composition

“…Total body reserves of the breeder hen can be changed by altering the growth curve during rearing and production ( Van der Klein et al, 2018 ; Heijmans et al, 2021 ). A 15 to 22% higher growth curve from 0 to 60 wk of age resulted in approximately 200 to 230 g more body fat at 55 to 60 wk of age ( Van der Klein et al, 2018 ; Zuidhof, 2018 ; Heijmans et al, 2021 ) and approximately 65 g more breast filet, as an indicator for more body protein ( Van der Klein et al, 2018 ). It can be hypothesized that more body reserves of the breeder hen is beneficial for egg production and egg composition ( Ekmay et al, 2014 ; Salas et al, 2017 ).…”

“…Another strategy to change breeder body reserves, while maintaining a similar BW, is by altering the dietary energy-to-protein ratio. In broiler breeders, feeding diets with 25% lower dietary CP or 8% higher dietary energy concentration from 0 to 60 wk of age resulted in 5 to 11% more body fat at the same BW ( Lesuisse et al, 2017 ; Zuidhof, 2018 ; Heijmans et al, 2021 ). Body fat is mobilized for yolk production ( Salas et al, 2017 ) and consequently, it can be hypothesized that more body fat will be beneficial for yolk production and eventually chick quality ( Nangsuay et al, 2015 ).…”

Effect of energy and dose of vitamin E selenium on improving the reproduction performance of Joper brood stock

“…Energy will be stored in the form of body fat mass when maintenance requirements are fulfilled. Body fat mass has an important role in metabolism including as a precursor in the synthesis of reproductive hormones [14], to maximize the absorption of vitamin E-selenium and egg yolk lippoprotein synthesis [15]. Lippoprotein synthesis in broiler breeding is higher than that of laying hens for egg consumption purposes.…”