The aim of this study was to investigating the effects of partially replacing the commercial soybean meal (SBM) by locally produced raw, full-fat soybean (RFFSB) in diets of layers. After cleaning, the tested ingredient (RFFSB) was hammered to pass through a 0.2-mm sieve. Then, four experimental diets were formulated by replacing the SBM by RFFSB at 0, 15, 30 or 45% (equivalents to 0, 30, 60 or 90 g/kg of diet, respectively). Before the commencement of this feeding trial, birds were uniformly managed and fed as per their requirements (i.e., starter, grower and pullet diets). This feeding trial was started when birds’ age was 24 weeks. Every treatment was replicated 4 times and 17 laying birds per replicate. The results revealed that replacing the commercial SBM by raw soybean (up to 45%) in the layer diets had no negative effects on the final live BWT and also on the vital organ developments, such as pancreas, duodenum, intestines and gizzard. Hen-day egg production, hen-housed egg production and egg quality measuring parameters were not significant affected by that of partially replacing the commercially SBM by the raw soybean. It is concluded that without compromising the productivity and health, a hammered RFFSB can replace (up to 45%) the commercial SBM in diets of the laying hens.

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.

Most poultry farmers in Nigeria feed their laying birds twice a day with one bag of 25 kg to 200 layers which translate to 125g/bird/day, while very few feed once or thrice a day and there has been little or no documentation on how many times laying hens should be fed in a day to optimize profit. Thus, this study was designed to investigate the performance and egg qualities of Isa-Brown layers fed different quantities of feed at varying feeding frequencies. Three hundred and sixty (360) 16-weeks in-lay Isa-Brown layers were used in this trial. The treatment consisted of 95g, 105g, 115g, and 125g of feed per day at varying frequencies of once, twice and thrice per day. The birds were housed in California type cages, 3 birds per cage unit, 5 cage units per replicate, and 6 replicates per treatment. A completely randomized experimental design with a 4x3 factorial was adopted. Results at the end of the trial showed that bird fed 115g of feed twice per day had the highest percentage hen-day production (85.24%), highest egg mass (56.69g) and best feed conversion ratio (1.96) while lowest percentage hen-day production (62.02%) and lowest egg mass (39.22g) were observed in hen fed 95g of feed thrice per day and worst feed conversion ratio (2.50) was recorded in bird fed 125g of feed thrice per day. The bird fed 115g twice per day had the highest net profit (N637.63) while the lowest net profit (N199.33) was recorded in bird fed 125g thrice per day. It could be concluded that for optimum laying performance and to save time and labour expended in feeding birds thrice per day, feeding laying Isa-Brown birds the required feed quantity (115g) twice per day would be most economical.

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.

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.

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.

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.

Eggs were coated with propolis in order to determine its effect on egg quality and total bacterial count. Effect of storage time prior to propolis coating was also studied. Eggs were obtained from a local farm, coated with 0, 3, 6 or 9% of propolis and stored at 4 ºC with a humidity of 75% for 30 days. A total of 18 eggs were used for egg quality traits and 6 eggs were chosen for microbial activity for each group. Bacteria were recovered with sterile cotton swabs from egg surfaces. Colonies with different morphology and color were detected. 11 bacterial species were determined following the characterization of 14 isolates. Elevated levels of bacterial counts were detected for daily eggs, which were significantly higher than those stored for 30 days. The quality traits of the daily eggs have also been found higher compared with the other groups. It was observed that coating the eggs with varying concentrations of propolis lead to significant differences in the total bacterial counts of the eggshells. Moreover, the egg quality traits which decreased with the increase in storage time have not been further affected with propolis coating.

ATAK-S is a newly developed native hybrid layer. Although the laying performance of this hybrid has been studied and determined, the performance response of the hybrid to different environmental temperature conditions is not known. This study was therefore undertaken to determine the effect of cold and heat stress on egg quality traits. Hens were divided into three different groups; control (20°C), low (12°C) and high (32°C). A total of 360 hens, with 120 in each of the groups, were used in the study. Hens were held in three tier battery cages in an environmentally controlled poultry house. The study lasted for 3 weeks. No differences were found among different groups in terms of shape index, albumen height and Haugh unit of the egg quality traits. It was found that the differences among the heat groups in terms of egg shell breaking strength, egg weight, shell thickness and yolk colour were significant and the value of these traits decreased under the heat stress conditions, whereas they were not affected from the cold stress.