The purpose of this study was to determine the dietary effects of fruit pulps (dried tomato, apple and grape) on the performance and egg quality characteristics of laying hens. In this trial, 196 Lohmann sandy layers 25 weeks of age were distributed into four groups with seven replicates for 9 weeks. Trial groups fed following diets, control group basal diet (no additive), 4 % dried tomato pulp, 4% apple pulp and 2.5% grape pulp. Feed conversion rate was not affected by any addition of fruit pulps throughout the trial. The dietary inclusion of dried tomato pulp increased feed consumption, egg weight and egg production and decreased egg yolk malondialdehyde (MDA) levels on day of 1 compared to the control. Egg yolk MDA level was decreased with the addition of 4% tomato and apple pulp to the diet, but increased with the addition of 2.5% grape pulp to the diet on the day of 28. Moreover, the addition of dried tomato pulp to the basal diet significantly increased egg weight and egg yolk yellow color (a). As a result, this study provides evidence that adding up to 4% tomato pulp to diets may be used without adverse effects on laying hens’ productivity and may improve egg quality characteristics by decreasing MDA levels in the yolk.

In this study, the performance, egg quality, egg yolk colour and fatty acids profile of quails fed on diets containing different fat sources were determined. During 8 weeks trial, a total of 75, 10-weeks-old laying quails were used. Three diets were formulated to contain soybean oil (SBO), sunflower oil (SFO) and hempseed oil (HSO), respectively. The performance parameters were not significantly influenced by the dietary different oil sources. Eggshell ratio, eggshell thickness, eggshell breaking strength, egg shape index, egg yolk index, albumen index and egg yolk colour values (except a*) were not influenced by the different dietary oil sources. The a* value was significantly affected and the highest a* value was the HSO of group. The different oil sources supplementation to the diets was effective on fatty acid composition of the egg yolk. The highest value in terms of α-linolenic acid, total polyunsaturated fatty acids and total n-3 fatty acids were found in the diet fed group with HSO added. As a result; supplementation of different sources of oil to quail diets without negatively affecting performance and egg quality can be used to change the egg yolk fatty acid composition. Hempseed oil may increase the amount of total polyunsaturated fatty acids and total n-3 fatty acid content of egg yolk.

In this study, it was investigated the effect of clove oil supplementation at increasing levels into laying hens’ diets on performance, egg quality traits, some blood parameters and yolk TBARS (Thiobarbituric Acid Reagent) values. For this purpose 96 Lohman white laying hens, 28 weeks of age, were divided into four treatment groups. Control group was fed with basal diet (C) and treatment groups were fed with diets formed by addition of clove oil at 50 ppm (CO1), 100 ppm (CO2) and 150 ppm (CO3), respectively. During the trial, feed and water were given as ad-libitum, and poultry house was illuminated for 17 hours. Experiment lasted for 13 weeks. Addition clove oil at increasing rates into diet did not affect the live weight. The data analysed as polynomial showed that supplementation of clove oil into layer diet linearly improved feed conversion ratio and increased the egg production. But, daily feed consumption, egg weight, damaged egg ratio and egg quality parameters were not affected by treatments. Serum parameters such as triglyceride, glucose, aspartate aminotransferase, alanine aminotransferase and calcium were not affected by the clove oil supplementation. TBARS values in C, CO1, and CO2 were found higher than the CO3 group fed with diet including 150 ppm clove oil. In conclusion, clove oil at 150 ppm level in diets of laying hens could be used due to extend the egg shelf life and to decline serum cholesterol content.

To improve hen welfare, several studies have investigated various environmental enrichments that suit different laying hen production systems. The positive results of these studies can enable such environmental enrichments to be utilized in commercial laying hen production. This paper reviewed the effects of environmental enrichments in different laying hen production systems on hen welfare and egg quality. The successfully proven environmental enrichments in free-range production system include forage, shelterbelt, and artificial shade in outdoor area and novel objects and H-shaped perching structures in indoor. These are associated with increased range use that positively affects hen welfare. In aviary system, perches, and litter materials (e.g., straw, sand) as environmental enrichments are linked to improved behavioral expression, reduced stress, and enhanced immune system. Under the litter system, environmental enrichment with substrates (e.g., pecking stones, alfalfa blocks, silage, straw, barley) has been found to increase the foraging behavior of laying hens. This reduces severe feather pecking thus, improving the plumage condition of hens. Although the effects of environmental enrichments on hen welfare have been assessed and scientifically proven in the reviewed studies, significant progress of their impact on egg quality traits has not been reported. The studies have shown that environmental enrichments have no significant effect on egg quality traits. Also, appropriate pasture or plant species as environmental enrichments in free-range production system in relation to hen welfare and egg quality have not been identified. Therefore, it is important to continue studies on environmental enrichments while emphasizing their influence on egg quality since it is a major performance trait in the egg industry. In addition, there is a need for studies to identify ideal pasture or plant species for free-range production system that positively affects hen welfare and egg quality.

An experiment was conducted to determine the effect of different combination calcium sources and particle size on performance and egg shell quality in layer hens. In the experiment, 198 brown laying hens at 44 week of age were randomly assigned into 11 treatments groups. The experimental diets consisted of different calcium sources (Fine limestone, large limestone, large oyster shell and large egg shell) and their different combination. The experimental unit consisted of a groups of three hens, thus each treatment was replicated six times. Different calcium sources and particle size addition to the laying hens diet had no significantly effect on body weight gain, egg production, egg mass, feed intake, feed conversion ratio, egg specific gravity, egg shell weight, egg shell thickness and egg shell breaking strength but egg weight had significantly affected by the treatments. The significantly highest egg weight was found in laying hens fed with 50 % fine limestone and 50 % large limestone. Dietary different Ca sources had a significant effect on Ca, P and Mg as mineral contents of eggshell and tibia. In the present study, when dietary large calcium sources (limestone, oyster shell and egg shell) had no effect on performance and eggshell quality parameters in laying hens. However, dietary containing at least 50 % large calcium sources had positive effect on mineral contents of tibia.

This study was conducted to determine the effect of rearing quails in different rearing systems on egg production, egg quality characteristics, and incubation results. The 360 quails were distributed equally to 3 different rearing groups (cage, enriched cage, and floor) in a male:female mixed at the age of 3 weeks. The eggs were individually weighed and recorded one by one daily (5487 eggs) for 3 months. To determine egg quality and incubation characteristics, 750 eggs were broken, and 3284 eggs were incubated, respectively. The results showed that female quail in the floor group have lower body weight at 6 weeks old (177.19 g), and they reached sexual maturity (age of first egg laying) later (65.36 day, P<0.01), The lowest egg production (61.14%) occurred in the floor group during the 3-month egg production period (P<0.05). The lowest average egg weight (9.07 g) was determined in the floor group (P<0.05). It was determined that the eggs of quails raised in the enriched group had a rounder shape index because they have larger widths (P<0.01). While the highest average yolk height (11.24 mm) was determined in the enriched cage group (P<0.01), the highest averages of albumen length (72.41 mm) and lowest averages of yolk index (48.43%) were determined in the cage group (P<0.01). The lowest average values (113.17) in Haugh unit were detected in the floor group (P<0.05). The highest fertility rate (98.44%) was in Floor♂:Cage♀, the highest hatchability of fertile egg rate (94.67%) was obtained from Enriched♂:Cage♀, and the highest hatchability (89.10%) was obtained from Floor♂:Cage♀ pairing (P<0.05). The lowest fertility rate (88.00%) was obtained from the Enriched♂:Floor♀, the lowest hatchability of fertile egg rate (86.01%) was obtained from the Enriched♂:Enriched♀, and the lowest hatchability (75.62%) was obtained from the Enriched♂: Enriched♀ groups. As a result, it has been revealed that the effect of various rearing systems is different on egg production, egg quality traits, and hatching results in quails. Thus, it has been shown that different programs at the rearing period to be applied to the male and female quails can achieve better incubation results and reproductive success.

This study was conducted to determine the effect of rearing quails in different rearing systems on egg production, egg quality characteristics, and incubation results. The 360 quails were distributed equally to 3 different rearing groups (cage, enriched cage, and floor) in a male:female mixed at the age of 3 weeks. The eggs were individually weighed and recorded one by one daily (5487 eggs) for 3 months. To determine egg quality and incubation characteristics, 750 eggs were broken, and 3284 eggs were incubated, respectively. The results showed that female quail in the floor group have lower body weight at 6 weeks old (177.19 g), and they reached sexual maturity (age of first egg laying) later (65.36 day, P<0.01), The lowest egg production (61.14%) occurred in the floor group during the 3-month egg production period (P<0.05). The lowest average egg weight (9.07 g) was determined in the floor group (P<0.05). It was determined that the eggs of quails raised in the enriched group had a rounder shape index because they have larger widths (P<0.01). While the highest average yolk height (11.24 mm) was determined in the enriched cage group (P<0.01), the highest averages of albumen length (72.41 mm) and lowest averages of yolk index (48.43%) were determined in the cage group (P<0.01). The lowest average values (113.17) in Haugh unit were detected in the floor group (P<0.05). The highest fertility rate (98.44%) was in Floor♂:Cage♀, the highest hatchability of fertile egg rate (94.67%) was obtained from Enriched♂:Cage♀, and the highest hatchability (89.10%) was obtained from Floor♂:Cage♀ pairing (P<0.05). The lowest fertility rate (88.00%) was obtained from the Enriched♂:Floor♀, the lowest hatchability of fertile egg rate (86.01%) was obtained from the Enriched♂:Enriched♀, and the lowest hatchability (75.62%) was obtained from the Enriched♂: Enriched♀ groups. As a result, it has been revealed that the effect of various rearing systems is different on egg production, egg quality traits, and hatching results in quails. Thus, it has been shown that different programs at the rearing period to be applied to the male and female quails can achieve better incubation results and reproductive success.

This study aimed to determine the structural relationship between internal and external egg quality (IEEQ) traits. In this study, 114 eggs produced from 24 weeks-old laying hens reared at the Ondokuz Mayis University Research Farm were used. Egg weight (EW), egg width (EWi), egg length (EL) and shell weight (SW) measurements were examined as external quality traits. Also, albumen height (AH), albumen width (AW), yolk height (YH), yolk weight (YW) and yolk diameter (YD) parameters were used as internal quality traits. Structural Equation Model (SEM) was used to determine the relationships between IEEQ traits. Data analysis was performed with the LISREL package. It has been determined that the variables that are important in determining the external egg quality are SW, EWi and EL. When the variables explaining the internal traits were examined, it was determined that the YW, YD, AW, AH and YH were significant. It was determined that the relationship between external egg quality and internal quality was 0.96 and external quality explained the internal quality by 91%. It has been determined that the SEM used in this study is sufficient to explain the relationship between internal and external quality.

In this study, the eggs produced in uncontrolled village conditions were compared to free-range, organic and cage-system in two seasons, in autumn and spring, in terms of external and internal quality traits. In the autumn and spring period, 110 eggs were collected from the village eggs and 50 eggs from other production systems. In order to determine the fertility in the village eggs, 60 eggs were placed in a laboratory type incubator in both seasons and fertility control was made at the 18th day. All data of egg quality traits were performed by taking the average of the two seasons. Egg shape index, shell ratio, shell thickness, shell cleanness, shell defects, albumen and yolk traits differed significantly among production systems (P < 0.05). The lowest shape index, shell thickness and shell cleanness were found in village eggs. Higher shell rates were determined from eggs in cage and organic production compared to others (P < 0.05). The yolk height and yolk index were the lowest and the yolk colors were the darkest in the white cage eggs (P < 0.05). Brown cage eggs showed the better results in the majority of their quality traits. However, they had a higher meat and blood-spot level than other systems. In addition, the presence of cockerels in the village flocks caused the fertile eggs and approximately 85% fertility was obtained. Our results showed that it has become obvious that the village hen and free range hen eggs which can be marketed in high prices compared to the commercial eggs, have no superiority in terms of the traits they are considered. Besides, as they are significantly fertile, especially in hot summer months, according to storage duration and conditions, the probability of embryo development for these eggs has turned to be of high importance for consumption.