Influence of feed form and energy concentration of the rearing phase diets on productivity, digestive tract development and body measurements of brown-egg laying hens fed diets varying in energy concentration from 17 to 46 wk of age

Abstract

a b s t r a c tThe influence of feed form and energy content of the rearing phase diets on hen productivity, gastrointestinal tract (GIT) traits and body measurements was studied in brown-egg laying hens fed diets differing in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 12 treatments arranged as a (2 × 3) × 2 factorial with two feed forms (mash vs. crumbles) and three AME n concentrations of the rearing phase diets (low, medium and high) and two AME n concentrations (11.10 vs. 11.52 MJ/kg) of the laying phase diets. The AME n of the rearing phase diets differed in 0.42 MJ/kg in all three periods (1-5 wk, 5-10 wk and 10-17 wk of age). Hen productivity was determined from 17 to 46 wk and GIT and body traits were measured at 46 wk of age. The characteristics of the rearing phase diets did not affect any of the production, GIT traits or body measurements studied during the laying phase, except body weight gain (BWG) from 17 to 46 wk of age that was higher (P < 0.01) in hens that were fed mash during the rearing phase than in hens that were fed crumbles. An increase in the energy content of the laying phase diet from 11.10 to 11.52 MJ AME n /kg reduced feed intake (P < 0.001) and improved feed conversion ratio (P < 0.001) from 17 to 46 wk and reduced gizzard contents (P < 0.01) at 46 wk of age but did not affect any of the other production trait studied. The characteristics of the rearing and laying hen diets did not affect any of the GIT traits or body measurements at 46 wk of age. Body weight of the hens was positively (P < 0.001) related with body length, body mass index, tarsus length and tarsus diameter at this age. The data indicate that neither feed form nor energy concentration of the rearing phase diets affected subsequent hen performance. An increase in the AME n content of the layer diet from 11.10 to 11.52 MJ/kg decreased feed intake and improved feed conversion ratio but did not affect hen production or egg quality.

Influence of nutritional strategies on growth performance and digestive tract traits of brown egg laying pullets and subsequent effects on egg production

“…The data presented herein indicate that the potential beneficial effects of DF on the size and development of the GIT are not long lasting and disappear once the birds are fed a common commercial layer diet . In this respect, Saldaña et al (2016) reported similar size and development of the different organs of the GIT in 46 wk-old hens that were fed mash or crumble diets during the rearing phase, consistent with the results reported herein. Also, Saldaña et al (2015a) reported that the effects of feed form on the GIT traits of pullets from 0 to 17 wk of age, reverted quickly when the birds were changed from receiving crumbles to receiving mash diets.…”

“…From 17 to 46 wk of age, egg production was high in all hens, irrespective of the energy concentration of the diet, in agreement with data of Grobas et al (1999a,b) comparing diets with 2,680 and 2,810 kcal AMEn/kg and Saldaña et al (2016) comparing diets with 2,650 and 2,750 kcal/kg in brown egg-laying hens. Similar data have been reported by Jalal et al (2006) and Murugesan and Persia (2013) in Single Comb White Leghorn hens fed diets containing 2,800 to 2,900 kcal AMEn/kg.…”

“…However, egg production, egg weight, and egg mass were not affected by energy content of the diet. Similar results have been reported by Saldaña et al (2016) in hens fed diets with 2,650 and 2,750 kcal/kg and Grobas et al (1999a,b) in hens fed diets with 2,680 and 2,810 kcal AMEn/kg. Also, Jalal et al (2006) and Murugesan and Persia (2013) reported similar results in Single Comb White Leghorn hens fed diets with 2,800 and 2,900 kcal AMEn/kg.…”

“…Egg quality traits were not affected by the energy content of the layer diet, in agreement with data of Grobas et al (1999c), Junqueira et al (2006), and Saldaña et al (2016). In contrast, Wu et al (2005) and Pérez-Bonilla et al (2012b) reported a linear decrease in albumen quality as the energy concentration of the diet increased.…”

“…In the current research, an increase in the fiber content of the rearing diets or in the energy of the laying hen diets had no effects on these traits at 46 wk of age. Similarly, Saldaña et al (2016) did not find any difference in body length or tarsus measurements in 46 wk-old hens that were fed mash or crumble diets differing in 50 kcal AMEn/kg during the rearing phase or diets differing in 100 kcal AMEn/kg from 17 to 46 wk of age.…”