Osman Olgun

The effect of dietary calcium concentration and particle size on performance, eggshell quality, bone mechanical properties and tibia mineral contents in moulted laying hens.

1. A total of 72 H&N Brown Nick laying hens, 76 weeks of age (moulted at 60 weeks of age), were randomly assigned into a 3 × 3 factorial arrangement with three limestone particle sizes and three dietary Ca concentrations (30, 36 and 42 g/kg Ca); with 8 replicates per treatments, and one hen (individual) per experimental unit. 2. Particle sizes of the limestone were: distributions smaller than 2 mm (Fine), between 2 to 5 mm (Medium), and larger than 5 mm (Large). The fine, medium and large limestone particles were all obtained from the same source, and sieve sizes used had screen sizes 2 mm and 5 mm. 3. The different concentrations of dietary Ca, particle size or interactions had no significant effect on egg production, egg weight, egg mass, feed intake or feed conversion ratio. 4. The concentrations of dietary Ca and particle sizes had no significant effect on egg breaking strength, eggshell as % by weight of whole egg or eggshell thickness. The interactions between Ca concentrations and particle sizes had a significant effect on eggshell breaking strength, but not on other parameters. 5. Different dietary particle sizes had no significant effect on the Ca, P and Mg mineral contents of eggshell. While the different concentrations of Ca in diets had a significant effect on the P content of eggshell, they had no significant effect on Ca and Mg contents. 6. Different dietary concentrations of Ca had a significant effect on shear stress, and Ca and Mg contents of tibiae, but not other parameters. Also, dietary particle sizes had a significant effect on shear stress and Ca contents of tibiae. The interaction between Ca concentrations and particle sizes had a significant effect on tibia shear force and Ca content. 7. According to the results of this study, moulted brown laying hens should be fed 36 g/kg Ca and a medium limestone particle size (2–5 mm) in the diet to maintain performance, eggshell and bone quality.

Effect of supplementation of different boron and copper levels to layer diets on performance, egg yolk and plasma cholesterol

PROCEDURE This study was conducted to determine the effects of supplementation of different levels boron and copper on performance, lipids in yolk and plasma contains in layer diets. In this trial a total of 320 layer chicken (26 weeks old age) was randomly distributed in 16 experimental groups. In each experiment group were consist at 5 replicates, and in each replicates there were 4 birds. During the 16 weeks experiment period, birds were fed with 16 experimental diets. Experimental diets were consisting of all possible combination of 4 levels of added boron (0, 60, 120 and 240 mg/kg) and 4 levels of added copper (0, 75, 150 and 300 mg/kg) to the basal ration. RESULTS Effect of treatments on body weight change and plasma glucose levels were not significant. However, added boron and copper had a significant effect on plasma high-density lipoprotein cholesterol fraction. While added boron had a significant adverse effect on performance parameters, added copper had a significant positive effect on the same parameters. Yolk lipid contents were increased by addition of boron to the ration. However, yolk lipid contents were decreased by addition of copper to the ration. Plasma lipid contents were also decreased by addition of copper and boron in the ration. CONCLUSION Results of the present study showed that laying hens from 26 to 42 weeks of age should be fed with 60 mg/kg boron and 150 mg/kg copper supplementation in the diet.

Effects of xylanase enzyme supplementation to corn/wheat-based diets on performance and egg quality in laying hens

This study was conducted to determine the effects of xylanase supplementation of corn/wheat-based diets on the performance and egg quality of laying hens. At 52 wk of age, 180 White Leghorn LSL laying hens were fed 15 diets, consisting of five corn:wheat ratios and three levels of enzyme. None of the treatments affected performance or egg quality, except for egg yolk index and egg yolk color. The egg yolk color was improved by the increase in dietary corn level. It is concluded that wheat can be used instead of corn as an energy feedstuff in laying hen diets. Key words: Egg quality, laying hen, performance, xylanase

THE EFFECTS OF SUPPLEMENTATION BORON, ZINC AND THEIR CADMIUM COMBINATIONS ON PERFORMANCE, EGGSHELL QUALITY, REPRODUCTIVE AND BIOMECHANICAL PROPERTIES OF BONE IN QUAIL BREEDERS

This study was conducted to determine the effects of dietary boron, zinc and their combinations to polluted diets with cadmium on performance, eggshell quality, reproductive and biomechanical properties of tibia in quails. A total of 60 male and 120 female quails, 20 weeks old, were randomly distributed in six equal diets groups. Diet I was control group, Diet II was added 20 mg/kg cadmium. Diet III was administered 20 mg/kg cadmium + 60 mg/kg boron. Diet IV was administered 20 mg/kg cadmium + 50 mg/kg zinc. Diet V was administered 20 mg/kg cadmium + 30 mg/kg boron + 25 mg/kg zinc. Diet VI was administered 20 mg/kg cadmium + 60 mg/kg boron + 50 mg/kg zinc. Effect of treatments on body weight, egg weight, feed intake, mortality, eggs damaged, specific gravity, eggshell weight, shear force, shear stress and hatchability were not significant (p>0.05). However, the diet VI had a significant adverse effect on the some performance parameters (egg production, egg mass and feed conversion ratio). Egg quality and fertility were improved by the addition of cadmium. Cortex thickness and cortex cross section area of tibia were the best when quails fed with diet III. Results of the present study showed that the supplementation of 20 mg/kg cadmium to the diets had positive effect on eggshell quality in quail breeders.

Manganese in poultry nutrition and its effect on performance and eggshell quality

Manganese (Mn) is an element required in nutrition, functioning largely in the enzyme systems involved in lipid and carbohydrate metabolism. It plays an important role in growth, bone development, perosis prevention, optimal eggshell quality and performance maintenance of poultry. The current NRC (1994) guidelines recommend 20 and 60 mg/kg of Mn for laying hens and broilers, respectively. In practical poultry feeds, however, the dietary requirement of Mn is considered higher than these values. Traditionally, Mn is added to the diet in the sulphate form, which is typically used as the standard in nutritional studies. However, in recent times, other, more natural forms have been made available to the feed industry, e.g. organic chelates. From this current review of published data, it appears that inorganic Mn supplementation up to 200 mg/kg is ineffective on the performance of both laying hens and broilers but at lower levels it improves eggshell quality. The dietary Mn requirement of laying hens and broilers appears to be 90 mg/kg, and the availability of Mn-sulphate is higher than that of other inorganic Mn sources but lower than its organic sources. More studies should be undertaken to determine the optimum Mn requirement in its various forms for laying hens and broilers.

The Effect of Dietary Essential Oil Mixture Supplementation on Performance, Egg Quality and Bone Characteristics in Laying Hens

Abstract The aim of this study was to investigate the effect of seven different levels (0, 25, 50, 100, 200, 400, and 600 mg/kg) of a phytogenic feed additive containing a mixture of essential oils from thyme, black cumin, fennel, anise and rosemary on performance, eggshell quality, bone biomechanical properties and bone mineralization in laying hens. This study consisted of a total of 112, 21-week-old Super Nick laying hens, which were randomly distributed into seven experimental groups. During the 12-week experimental period, each experimental group of four replicates of four birds each was fed with seven treatment diets. Egg weight and egg mass were positively linearly affected by essential oil mixture supplementation. Also, eggshell thickness was increased quadratically by essential oil mixture supplementation. The biomechanical properties and tibia mineral content were adversely affected by essential oil mixture supplementation at the level of 600 and 400 mg/ kg, respectively. These results demonstrated that dietary supplementation with a low or medium concentration of essential oils improved bone parameters, while at high levels were adversely affected in laying hens.

Effects of carbohydrase enzyme supplementation on performance, eggshell quality, and bone parameters of laying hens fed on maize- and wheat-based diets

ABSTRACT 1. This study was conducted to determine the effects of enzyme supplementation of maize/wheat-based diets on the performance, egg quality, and serum and bone parameters of laying hens. 2. During the 12-week experimental period, a total of 72 laying hens aged 52 weeks were randomly distributed among 6 experimental groups. Each experimental group contained 4 replicates, each with three birds. The experiment was a randomised design consisting of a 3 × 2 factorial arrangement, with three levels of wheat substitution and two levels of enzyme (xylanase: 1500.00 U/kg, β-glucanase: 100 000 U/kg, cellulase: 1 000 000 U/kg, α-amylase: 160 000 U/kg) inclusion in the diet. Wheat replaced 0, 50, or 100% of maize with or without 1.0 g/kg enzyme supplementation in iso-nitrogenous and iso-caloric experimental diets. 3. Body weight, egg production, egg weight, egg mass, eggshell thickness, and the feed conversion ratio were adversely affected by the wheat-based diet. The eggshell quality parameters decreased with enzyme supplementation to the diet. 4. Wheat-based diets adversely affected calcium and phosphorus concentrations in the tibia, but the addition of the enzymes to the wheat-based diet prevented the negative effects of wheat-based diets on tibia mineralisation in laying hens. The wheat-based diets tended to reduce plasma mineral contents, and the addition of enzymes tended to affect plasma minerals and biomechanical properties of the tibia positively in laying hens. 5. These results indicate that wheat-based diets in aged laying hens adversely affected the mineral metabolism compared with maize-based diets, and the negative effects of wheat on bone mineralisation can be prevented by enzyme supplementation to the diets in laying hens.

Effects of dietary supplementation of inorganic, organic or nano zinc forms on performance, eggshell quality, and bone characteristics in laying hens

Abstract This study was conducted to evaluate the efficiency of dietary zinc forms and dosages on egg production performance, egg quality, and bone characteristics in laying hens. Forty-two-week-old, 144 Lohmann LSL-Lite laying hens were allocated to 12 experimental groups in a 4 (forms) × 3 (dosages) factorial arrangement. Four zinc forms including zinc-sulphate and zinc-oxide as inorganic forms, zinc-glycine as organic form and nano zinc-oxide powder as nano form at different dosages (50, 75 and 100 mg per kg diet) were tested. Compared to the inorganic (zinc-sulphate) form, the zinc-glycine supplementation significantly depressed the egg weight, egg mass and feed conversion ratio. The eggshell thickness was significantly decreased by supplementation with nano zinc-oxide. The shear force of tibia was significantly decreased by zinc-glycine or nano zinc-oxide supplemented in the diet when compared to inorganic forms of zinc. On the other hand, the dietary 50 mg/kg dosage of zinc was sufficient for optimum performance and the dietary 75 mg/kg dosage of zinc significantly improved shear force of tibia in laying hens. Tibia zinc content increased with the dietary 100 mg/kg dosage of zinc. The interactions between zinc forms and dosages had a significant effect on egg weight, feed intake, feed conversion ratio, eggshell thickness, shear force and shear stress of bone, and tibia calcium concentration. The highest egg weight and the lowest eggshell thickness were observed for the group fed with nano Zn-oxide at 100 mg/kg in the diet. These results showed that nano zinc form supplementation negatively affects the eggshell thickness and bone mechanical properties. The zinc in nano form may not be suggested for feeding laying hens, but other forms of zinc could be used safely in layer diets.

Nutritional factors affecting the breaking strength of bone in laying hens

The bone is a mineral reserve for metabolic requirements and eggshell formation as well as providing support to the bodies of birds. Bone weakness in laying hens has caused many problems such as bone deformation, osteoporosis, cage layer fatigue and fractures. These problems result in economic losses and are detrimental to animal welfare. Breaking strength is a good indicator of the health and strength of bone and an increase in breaking strength in laying hens would be important to decrease economic losses and improve the welfare of animals. One of the main factors affecting bone breaking strength is nutrition, as it is closely related to dietary calcium, phosphorus, vitamin D and particle size of the calcium source, particularly when the dietary calcium is insufficient. It has been accepted that the composition of the diet, trace elements, especially boron, vitamins, and feed additives play important roles in maintaining bone health and improving the breaking strength of bone in laying hens. This article reviews the results of studies in laying hens wherein the effect of nutrition on the breaking strength of bone were examined.

The effects of eggshell and oyster shell supplemental as calcium sources on performance, eggshell quality and mineral excretion in laying hens

A study was conducted to determine the influence of different calcium sources in layer diets on performance, eggshell quality and mineral excretions. A total of 72 Hy-Line W36, layer birds of 25 weeks old, were distributed in 6 experimental groups randomly. In each experiment group there were 4 replicates, and in each replicates there were 3 birds. During the 12 weeks experiment period, birds were fed 6 experimental diets. Experimental diets were consisted of various calcium sources for meeting the calcium requirements. It was control (limestone), 1/3 eggshell, 1/3oyster shell, 1/3 eggshell+1/3 oyster shell, 2/3 eggshell and 2/3 oyster shell. Dietary different sources of calcium had no significant effect on body weight change, feed conversion ratio, eggshell breaking strength, eggshell thickness, and eggshell phosphorus and magnesium contents (p > 0.05). The different sources calcium had a significantly effect on egg production, egg weight, egg mass, feed intake and eggshell weight in laying hens (p