This study was conducted to investigate the performance of laying hens and to determine possible age-related changes on external and internal quality traits of their eggs and synthesis of heat shock protein 70 kDa (HSP70) in the conventional cage and organic rearing systems. For this purpose, 4 different Bovans White hybrid flocks of the same age were monitored in each of these two systems for 52 weeks. While a total of 360 eggs were examined to determine the effects of rearing system and age (30 and 60 weeks) on egg quality traits, 48 liver tissue samples were examined for the analysis of HSP70. Egg production (hen-day) and dirty egg ratio were higher in the organic rearing system (P<0.05). The age at 50% yield, the age at peak of lay, and peak production rate were calculated as 156, 218.75 days and 95.98% in the conventional system, and 155.75, 201.50 days, and 96.56% in the organic system, respectively (P>0.05). While egg weight, albumen weight, yolk weight, shell weight, shape index, and yolk colour were higher in the organic system, the crude ash ratio of eggshell and shell ratio were higher in the conventional system (P<0.05). It was also found that the egg weight, albumen weight, yolk weight, shell weight, and the percentage of yolk were higher at 60 weeks of age (P<0.001). The percentage of shell and albumen, shape index, and yolk colour were higher at 30 weeks of age (P<0.001). The interactions between rearing system and age were statistically significant in terms of shell thickness, shape index, crude ash ratio, and yolk colour (P<0.001). Stress protein (HSP70) level was affected only by the rearing system and was higher in the organic system (P<0.001). As a result, the organic system can be considered as advantageous in terms of egg production and quality traits and the eggs of young hens exhibited better properties. The high level of HSP70 in the organic system could indicate that hens were affected by the environmental conditions at higher rates and/or the hens reared in the organic system had a stronger antioxidant defence system.

This study evaluated effects of photoperiod treatments on slaughter and carcass traits, meat quality, indicators of oxidative stress, and heat shock protein 70 (Hsp70) levels of lung and heart tissues in broilers. Five hundred Ross 308 broiler chicks were used. The treatments consisted of 23 hours of continuous light and one hour of darkness (23L1D), four hours of light followed by two hours of darkness (4L2D), eight hours of light and four hours of darkness (8L4D), and 16 hours of light and eight hours of darkness (16L8D). After 42 days, two birds from each replicate were slaughtered. Birds that had been subjected to 16L8D had lower slaughter, carcass, and breast weights than the other treatments. Significant correlations were observed for slaughter, carcass and breast weights and white stripe. At 10 min post mortem, the pH of the breast was the highest in 23L1D. Breasts from birds subjected to 23L1D and 16L8D had most fat and least protein, while white striping was not different among treatments. The 4L2D treatment resulted in the highest lung glutathione (GSH) concentration. Malondialdehyde (MDA) and GSH concentrations in the heart tissues of broilers from 8L4D and 4L2D were greater than those from 23L1D and 16:8. Glutathione peroxidase (GSH-Px) and superoxide dismutase concentrations were greatest for birds subjected to 16L8D. Heat shock protein 70 was lowest in lung and heart from birds subjected to 8L4D. Thus, shorter and more frequent periods of darkness can be recommended for welfare with little compromise in performance. Keywords: carcass quality, heat shock protein 70, oxidative stress, white stripe

This study aimed to reveal phenotypic correlations of some internal and external egg quality traits between egg white (albumen) pH and ovalbumin levels in four different varieties of Japanese quail. A total of 480 eggs were used belong to gray, white, golden and black plumage color Japanese quail obtained from a commercial quail breeding company. Each group consisted of 120 eggs collected from the birds which were same age. After determined the external traits, all eggs were broken, albumen and yolk separated and internal traits were examined. Albumen pH was measured after the separation process. SDS-PAGE was applied for determining the ovalbumin level. A positive correlation was observed between egg weight and albumen (0.838) and yolk weight (0.599). There was a negative correlation determined between egg weight and albumen pH (-0.431). The percentage of yolk and albumen pH had a moderately significant positive correlation (0.350). We observed significant correlation between yolk color and albumen pH as well as between genotype of birds (P<0.01). The ovalbumin level high positively correlated with only the birds' genotype (0.814). Black plumage color (67.69%) had the highest ovalbumin level amongst golden (64.76%), white (49.28%) and gray (46.84%) plumage colors, respectively. The novel data is presented in this study about ovalbumin level comparing in four varieties of Japanese quail. The ovalbumin level is not affected by any quality features except for the genotype. The studies need to be conducted under different storage conditions for revealing more accurate phenotypic correlations between egg quality traits and albumen pH.

The objective of this study was to determine the effects of grape seed (GS) supplementation to basal diet on performance, carcass characteristics, some biochemical parameters, and antioxidant status of tissues of Japanese quail in growth phase with different plumage colors exposed to heat stress (HS). A total of 144 eight-day-old Japanese quail including 72 (36 females, 36 males) grey and 72 (36 females, 36 males) golden were used in this study. The quail were kept under HS (16 h at 34 ºC, 8h at 22 ºC) and thermo-neutral (24 h at 22ºC) conditions between 15 and 43 days of age. All quail were fed a basal diet (control) and basal diet supplemented with GS at both 10 g/kg and 20 g/kg ratios. Each feeding treatment was repeated three times including four quail (two females and two males) per replicate. Heat stress considerably decreased the live weight gain on days 29-36, 36-43, and 15-43. Golden quail had higher live weight from the beginning of the trial. The increase of live weight on days 15-43 was higher in the golden group than in the grey group. Malondialdehyde (MDA) levels of liver and kidney tissues increased in heat-stress group compared with thermo-neutral group (P<0.001). In HS, significant increases were determined only in catalase (CAT) in the liver and in glutathione peroxidase (GSH-Px), CAT, and glutathione (GSH) in the kidney (P<0.05). Addition of dietary GS decreased MDA and antioxidant levels, which increased in liver and kidney of quail during HS. Plasma total cholesterol, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels were higher in quail under HS. Plasma total cholesterol, glucose, triglyceride, AST, and ALT levels of quail under HS decreased due to addition of 10 g/kg GS.

The aim of the current study was to determine the impact of in-ovo injected D-Glucose monohydrate and ascorbic acid on hatchability, body weight and early post-hatch performance of geese. The 360 eggs from a 50-wk-old Embden crossbred breeder flock were set in a single-stage incubator with 4 treatments. The experimental treatments were: (1) non-injected Control, (2) Dextrose 24 mg / 0.5 mL, (3) Vitamin C 10 mg / 0.1 mL (4) Dextrose 24 mg / 0.5 mL + Vitamin C 10 mg / 0.1 mL. At 11 and 18 d of incubation, the eggs were injected into the albumen manually under sterile conditions. At 25 d of incubation, the same amount of the agents was injected into the yolk sac of the fertile eggs with the same procedure. The hatchability of the Control and Dextrose + Vitamin C groups were statistically different (P < 0.05). Although there was a statistically insignificant difference, the highest value was recorded in the Dextrose + Vitamin C group on the 25th-day. The hatchling weights were only influenced by the agents. The 25th-day Dextrose + Vitamin C treatment had the greatest values at body weights at hatch. There were no statistical differences by the injection days, agents and interactions regarding body weights at 7th-day post-hatch. In addition, there was no significant impact of different injection sites on both hatchling weight and, body weights of post-hatch 7th-day. It is suggested that the in-ovo injection should administrate on the 25th day of incubation into the yolk sac in goose eggs with a mixture of D-Glucose monohydrate and ascorbic acid.