Effect of dietary energy on performance and egg composition of Bovans White and Dekalb White hens during phase I

Abstract

A 4 x 2 factorial experiment with 4 dietary energy levels (2,719, 2,798, 2,877, and 2,959 kcal of ME/ kg) and 2 strains (Bovans White and Dekalb White) was conducted to determine the effect of dietary energy on reproductive performance, egg composition, and profits of 2 strains of commercial Leghorns. This experiment lasted 16 wk. Bovans White hens (n = 768) and Dekalb White hens (n = 768) in phase I (21 wk of age) were randomly assigned into 8 treatments (16 replicates of 12 birds/treatment). Bovans White had significantly higher feed intake, egg production, egg mass, body weight, percentage egg yolk, and yolk/albumen ratio than Dekalb White. Bovans White had significantly lower feed conversion, egg weight, egg specific gravity, percentage of albumen weight, percentage of shell weight, and Haugh unit than Dekalb White. When dietary energy increased from 2,719 to 2,956 kcal of ME/kg, hens adjusted feed intake from 107.6 to 101.1 g/hen per day to achieve a constant energy intake so that the same amount of dietary energy (5.8 kcal) was used to produce 1 g of egg. Increasing dietary energy by the addition of poultry oil increased early egg weight, which was mostly due to increased yolk weight. Increasing dietary energy by addition of poultry oil significantly decreased feed conversion and egg specific gravity but had no effect on egg production, egg mass, body weight, or mortality. Increasing dietary energy by addition of poultry oil to a ratio of 282 kcal of ME/g lysine maximized egg weight during phase I. The energy per lysine ratio required for optimal profits varied with egg price and feed ingredient prices, which were variable.

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

“…In regard to dietary energy, Grobas et al (1999b) and Pérez-Bonilla et al (2012a) observed similar egg quality (dirty, broken, shell-less, Haugh units, yolk pigmentation and yolk to albumen ratio) for hens fed diets containing 11.10 or 11.52 MJ AME n /kg, in agreement with the results reported herein. However, Zimmermann and Andrews (1987) and Wu et al (2005) observed a reduction in albumen quality and Junqueira et al (2006) a decrease in the percentage of shell-less eggs with increases in the energy concentration of the diet. Factors such as strain and age of the hens, as well as the ingredient composition of the diet, might affect the response of egg quality traits to variations in energy content of the diet.…”

“…Factors such as strain and age of the hens, as well as the ingredient composition of the diet, might affect the response of egg quality traits to variations in energy content of the diet. For example, Zimmermann and Andrews (1987) and Junqueira et al (2006) used Leghorn hens in the second cycle of egg production and Wu et al (2005) reported that the decrease in AME n of the diet reduced yolk size, which in turn could affect egg size and other egg quality traits.…”

Effects of Lowering the Dietary Levels of Energy, Protein and Amino Acid (Methionine and Cysteine) on the Performance of Laying Hens

“…Feed intake was significantly decreased with the higher levels of dietary energy (Wu et al, 2005a(Wu et al, , 2005b. Similarly, as the methionine + cysteine level increased from (0.61%, 0.68%, 0.75% and 0.82 to 0.89%), a linear reduction was observed in the feed intake (P<0.01) of brown-egg laying hens (Filho et al, 2006).…”

Yumurta tavuklarında yerleşim sıklığı, rasyon enerji düzeyi ve rasyona karnitin ilavesinin teknik ve ekonomik açıdan değerlendirilmesi

“…Elde edilen bulgular, tavukların yem tüketimini enerji ihtiyaçlarına dolayısıyla rasyon enerji düzeyine göre ayarlayabilmelerine bağlı olarak, rasyon enerji düzeyi arttıkça yem tüketiminin azaldığı yönün-deki çalışmaları desteklemektedir (16,17,36,37). Tavukçulukta toplam maliyetler içerisinde en önemli payı yem gideri aldığından yem tüketiminin düşük olması, üretim maliyetlerinin de büyük oranda azalmasına dolayısıyla işletme kârının artmasına yol açmaktadır.…”