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A week study was conducted to evaluate the productive performance of Bovans White laying hens fed high-nutrient-density diets under Egyptian summer conditions. Two hundred hens were randomly assigned to five equal dietary treatments, five replications each. Birds were kept at community cages in an open-sided laying house, provided with a daily photoperiod of 16 h and managed similarly. Four high nutrient density diets were also compounded to contain The criteria of response were feed intake, egg production, egg weight, egg mass, feed conversion , body weight change, egg components and certain traits of egg quality, nutrient digestibility and some blood plasma parameters.
Feeding the high nutrient density diets exerted no positive effect on productive performance of hens, digestibility of nutrients dry matter , organic matter , crude protein , ether extract, crude fiber, nitrogen-free extract and ash retention , some egg quality traits and most blood parameters examined but positively affected weight change, percent albumen, shell thickness, yolk index and Haugh units.
High ambient temperatures have been reported to adversely affect feed intake, egg production, egg weight and feed conversion in laying hens Daghir, The reduction in egg production and egg weight is primarily due to reduced feed intake, resulting from exposure to high environmental temperatures.
In addition to the effect of heat stress on the feed intake of chickens, protein digestibility can also be reduced Bonnet et al.
In this respect, Kamar et al. Also, Wolfenson et al. Since, depressed appetite is the major causative factor for the reduced performance at high temperature s, efforts were attempted in order to more accurately define the nutrient requirements of heat-stressed laying hens Daghir, Dietary manipulations are among the nutritional strategies used to overcome the adverse effects of heat stress on the feed and energy intakes and productive performance of laying hens.
Dietary fat supplementation at high temperature is well known to decrease heat increment of the feed and can improve the voluntary feed intake of heat-stressed birds Daghir, Under thermoneutral conditions, Wu et al. In later study, Marie et al. The aim of the present study was to evaluate the productive performance of laying hens fed high-nutrient-density diets during the second phase of egg production cycle, under Egyptian summer conditions.
Ambient temperature and relative humidity, prevailing at the experimental period, ranged between Two hundred Bovans White laying hens 44 weeks old were randomly divided into five equal dietary treatments, each with five replications. Birds of each replicate group were housed in a community laying cage 8 pullets per cage with one feeder , the width, length and height of each cage were 80, and 80 cm, respectively.
The cages are placed in an open-sided laying house, supplied with an artificial light to provide a daily photoperiod of 16 h.
Experimental diets: A control diet was composed based on yellow corn, soybean meal and corn gluten meal to meet or exceed the nutrient requirements of Bovans White laying hens , as suggested by the Bovans White Management Guide CPI. Four high-nutrient-density diets were also compounded to contain Thus, five mash experimental diets were formulated and fed to laying hens kept under Egyptian summer conditions from 44 to 56 weeks of age.
Composition and chemical analyses of these experimental diets are illustrated in Table 1. Cumulative means of these variables were also calculated throughout the duration of the experiment.
Body Weight Change BWC as the difference between final and initial live body weights of hens was also estimated for the whole experimental period. Mortality was also monitored daily during the whole experimental period. Freshly-laid eggs 30 eggs per treatment were randomly chosen and used to determine some parameters of egg quality. The ESA was calculated using the following equation:. One replicate group per treatment was fed its respective experimental diet for a three-day test period.
Then, they were allowed to equilibrate in moisture with atmospheric air before being weighed, finely ground and stored in plastic bags until analysis. Fecal protein fraction was separated in excreta samples and urinary organic matter was calculated. Samples of experimental diets and dried droppings were chemically analyzed according to the official methods of analysis AOAC.
Blood parameters: Blood samples were collected from the wing veins of 56 weeks old hens in heparinized tubes. Level of plasma globulin was calculated by subtracting level of plasma albumin from that of total protein. Statistical analysis: The statistical processing of data was performed via one-way analysis of variance using the Statistical Analysis System SAS. No deaths were observed throughout this study. It was interesting to note that though DFI of hens was not affected by the experimental diets, hens fed the HND4 diet consumed insignificantly less feed than those of the other experimental groups.
The high similarity in DFI of hens fed the control, HND1, HND2 and HND3 diets is an indication that the ambient temperatures, prevailed under the conditions of this study, were not too severe to adversely affect feed intake of hens. So, the reduced feed intake of hens fed the HND4 diet might be attributed to the increased nutrient density of the diet rather than to the effect of heat stress per se.
In harmony with the present results, Panda et al. In addition, Zhang and Kim investigated the effects of feeding two dietary energy levels vs. They found that egg production was not affected by dietary energy or nutrient density but hens fed the high-energy and high-nutrient-density diets had significantly less daily feed intake than those fed the low-energy and low-nutrient-density diets throughout the experimental period. Moreover, Rama Rao et al. On the other hand, Wu et al.
In a later study, Marie et al. Recently, De Persio et al. Egg quality measurements of laying hens : Data on the effect of feeding high-nutrient-density diets on egg quality parameters of laying hens fed high-nutrient-density diets are introduced in Table 3. However, egg weight, percent albumen, shell thickness, yolk index and Haugh units were positively affected due to feeding the high nutrient density diets compared with those of the control group.
Although average egg weight during the entire experimental period was not affected by dietary treatments Table 2 , an improvement was observed in egg weight concurrent with increases in percent albumen, yolk index, Haugh units and shell thickness Table 3. There is no explanation for the concurrent increase in egg weight and shell thickness for hens fed the high nutrient density diets, under the conditions of this study.
The beneficial effect of feeding the high nutrient density diets on egg weight, percent albumen, shell thickness, yolk index and Haugh units, observed in this study, is in accordance with the findings of Marie et al.
However, Panda et al. In addition, Zhang and Kim found that hens fed high-energy and high-nutrient-density diets had no effect on egg quality traits of hens compared with those fed low-energy and low-nutrient-density diets.
More recently, De Persio et al. Nutrient digestibility of the experimental diets: Data on the effect of feeding the high-nutrient-density diets on nutrient digestibility of the experimental diets for laying hens are presented in Table 4. The lack of significant differences in nutrient digestibility of laying hens in response to feeding high-nutrient-density diets, under the conditions of the present study, coincides with the observed similarity in their achieved productive performance Table 2 , since dietary treatments had no effect on either feed intake or feed conversion ratio.
In harmony with the present results, Danicke et al. The present results harmonize also with the findings obtained by Han and Thacker , who evaluated the effects of feeding two dietary energy levels They found that dietary energy level had no significant effect on digestibility of organic matter , crude protein , ether extract or on the digestibility of essential amino acid s arginine, histidine, leucine, isoleucine, lysine, methionine, cysteine, phenylalanine, threonine, valine and glycine.
In partial agreement with the present results, Awad et al. They also observed that digestibility coefficients of dry matter , organic matter and nitrogen-free extract were not affected by dietary protein level, however, increasing dietary protein level significantly increased the digestibility of crude protein but decreased ether extract digestibility.
In contrast to the present results, Jalal et al. In addition, Novak et al. With broiler breeder hens, Enting et al. Inconsistent results in the scientific literature on the nutrient digestibility in laying hens due to feeding diets of varying nutrient concentration could be related to many factors, such as heat tress conditions constant high temperature s vs.
Blood parameters of laying hens : Data on the effect of feeding high-nutrient-density diets on blood plasma parameters of 56 weeks old Bovans White laying hens are given in Table 5.
It is established that MDA is formed as an end product of lipid peroxidation and therefore, the extent to which lipid peroxidation occurs by reactive oxygen species can be monitored by the level of MDA. The lower activity of SOD coincided with higher concentrations of GSH, MDA and triglycerides in plasma of hens fed the HND3 and HND4 diets might be an indication to enhanced lipid peroxidation by reactive oxygen species due to lower activity of the antioxidant enzymatic activity in the plasma of laying hens.
The observed insignificant differences in most blood parameters of Bovans White laying hens , examined herein, in response to feeding the high-nutrient-density diets agree with the results of Rabie et al. Working with Japanese quail, Rabie et al. In contrast to the present results, Zhang and Kim evaluated the effects of feeding the laying hens two dietary energy levels vs.
In addition, Roland et al. Subscribe Today. Science Alert. E: 20 g, Vit. B 12 : 15 mg, Ca pantothenate: 12 g, Niacin: 40 g, Folic acid: 1. All Rights Reserved. Research Article. Ismail , Hayam M. Abo El-Maaty , M. Rabie and A. Similar Articles in this Journal. Search in Google Scholar. Report Citation. How to cite this article: F. Ismail, Hayam M. Abo El-Maaty, M. Aswad, Asian Journal of Animal and Veterinary Advances, DOI: Table Productive performance of laying hens fed high-nutrient-density diets from 44 to 56 weeks of age.
Egg components and some egg quality parameters of laying hens fed high-nutrient-density diets, examined at 50 weeks of age. Nutrient digestibility of the experimental diets for 55 weeks old laying hens fed diets containing high nutrient densities. Blood parameters of 56 weeks old laying hens fed high-nutrient-density diets.
Official Methods of Analysis. Awad, A.
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