Quality of Eggs from Layers Reared under Alternative and Conventional System

The study aimed to compare and assess some of the quality characteristics (morphology, colour of the yolk, total carotenoid content and fatty acid profile) of eggs obtained from hens reared conventionally or in alternative system having access to pasture. Twenty eggs of each rearing system were analysed for the above characteristics. The eggs obtained from the layer reared under the alternative system were significantly heavier than the conventional ones, displayed higher diameters of the albumen and albumen index, as well as increased diameter and weight of the yolk. On the other hand, their shell thickness and Haugh units were lower when compared to the eggs from conventionally reared hens. The colour of the eggs from the alternative system was darker and they had lower values of L* and higher of a* in the yolk, corresponding to the significantly higher content of the total carotenoids in comparison to the eggs obtained from the hens reared conventionally. Furthermore, the eggs from the hens having access to pasture showed clear advantage in the fatty acid profile and the related lipid nutritional indices. In general, the rearing in alternative system reduced considerably the content of C14:0, C16:0, C18:0, C16:1n-7 and C18:1n-9, as well as the saturated (SFA) and monounsaturated fatty acids (MUFA). On the other hand, with the exception of C20:3n-6, the contents of both individual and total polyunsaturated fatty acids (PUFA) were dramatically increased in the eggs from the hens reared in the alternative system. This led to favourably decreased values of n-6/n-3 ratio as well as values of both atherogenic (AI) and thrombogenic (TI) indices but augmented ratio between hypo- and hypercholesterolemic fatty acids.(AU)

Quality of Eggs from Layers Reared under Alternative and Conventional System

The study aimed to compare and assess some of the quality characteristics (morphology, colour of the yolk, total carotenoid content and fatty acid profile) of eggs obtained from hens reared conventionally or in alternative system having access to pasture. Twenty eggs of each rearing system were analysed for the above characteristics. The eggs obtained from the layer reared under the alternative system were significantly heavier than the conventional ones, displayed higher diameters of the albumen and albumen index, as well as increased diameter and weight of the yolk. On the other hand, their shell thickness and Haugh units were lower when compared to the eggs from conventionally reared hens. The colour of the eggs from the alternative system was darker and they had lower values of L* and higher of a* in the yolk, corresponding to the significantly higher content of the total carotenoids in comparison to the eggs obtained from the hens reared conventionally. Furthermore, the eggs from the hens having access to pasture showed clear advantage in the fatty acid profile and the related lipid nutritional indices. In general, the rearing in alternative system reduced considerably the content of C14:0, C16:0, C18:0, C16:1n-7 and C18:1n-9, as well as the saturated (SFA) and monounsaturated fatty acids (MUFA). On the other hand, with the exception of C20:3n-6, the contents of both individual and total polyunsaturated fatty acids (PUFA) were dramatically increased in the eggs from the hens reared in the alternative system. This led to favourably decreased values of n-6/n-3 ratio as well as values of both atherogenic (AI) and thrombogenic (TI) indices but augmented ratio between hypo- and hypercholesterolemic fatty acids.

Effect of Dietary Inclusion of Sodium Bicarbonate on Digestibility of Nutrients and Immune Response in Caged Layers During the Summer

The aim of this project was to investigate the effect of dietary inclusion of sodium bicarbonate (NaHCO3) on nutrient digestibility and immune response of caged layers during summer when the temperature exceeds 40 C. For immune response trial, White Leghorn layers (n=160; 24 weeks old) were purchased from a poultry farm and were divided into five treatment/diets groups (4 replicate/treatment). Diet A, was without NaHCO3 and served as control whereas, diets B, C, D, and E contained 0.5, 1.0, 1.5 and 2.0% NaHCO3, respectively. All these birds were vaccinated against Newcastle disease (ND) virus at the start of the experiment and thereafter with one-month intervals. Blood samples were collected from two birds/replicate at 10 days post vaccination each time to check antibody titer against ND virus. For digestibility trial, fecal samples were collected (6 layers/treatment group) at the start of the 37th week of age for two days, at 3 hours interval. Results revealed that immune response against ND virus 10 days post vaccination after 1st, 2nd and 3rd month was significantly (p 0.05) higher in layer birds fed diets containing NaHCO3. Digestibility of dry matter (DM), crude protein (CP), crude fiber (CF), ether extract (EE) and absorption of minerals were also found to be significantly (p 0.05) higher in groups treated with NaHCO3 and the birds fed diet containing 1% NaHCO3 showed the best results. In general, results revealed that 1% supplementation of NaHCO3 in layers diet have a beneficial impact in terms of immunity and diet digestibility.(AU)

Inhibitory Effects of Some Flavonoids on Thioredoxin Reductase Purified from Chicken Liver

Thioredoxin reductases (TrxRs) are selenocysteine-containing flavoenzymes that reduce Trxin NADPH-dependent manner. In the view of the direct vital role of TrxR in a wide range of biochemical and physiological processes, methods to inhibit this enzyme are clinically important. TrxR has recently emerged as a new candidate in anticancer drug investigations because of overexpression in tumorous cells. In this study, TrxR from chick liver was purified 94.6-fold with a yield of 4.86% and a specific activity of 0.19 EU/mg. KM and Vmax values of TrxR for DTNB were calculated as 0.9 mM and 0,03 EU/mL, respectively. Then, the effects of the flavonoids hesperidin, naringenin, chlorogenic acid, ferulic acid, naringin, 3,4-dihydoxybenzoic acid, and ellagic acid on the enzyme activity were evaluated under in-vitro conditions. Ellagic acid showed the strongest inhibitory activity on TrxR with a IC50 value of 18 µM, followed by naringenin and chlorogenic acid with IC50 values of 46.7 µM and 75.8 µM, respectively. Our results showed that flavonoids as natural products are potential inhibitors of TrxRs and the flavonoid content in animal diets may alter metabolic pathways by influencing TrxR activity.(AU)

Effects of The Dietary Supplementation of Layer Diets with Natural and Synthetic Antioxidant Additives on Yolk Lipid Peroxidation and Fatty Acid Composition of Eggs Stored at Different Temperatures and Duration

In this study, the effects of the supplementation of natural and synthetic antioxidant additives in layer diets on egg weight loss, yolk lipid peroxidation (TBARS values) and fatty acid composition of eggs stored at different temperatures and duration were evaluated. In total, 112 48- weeks-old Bovans White layers were randomly allotted to four dietary treatments with four replicates of seven birds each. The treatments consisted of a control diet, containing no additives, and diets with the inclusion of 200 mg synthetic vitamin E/kg, 1000 mg thyme extract/kg and 1000 mg rosemary extract/kg. Dietary treatments did not influence (p>0.05) relative weight loss of eggs stored for 14, 28, and 56 days, except for those from rosemary-fed hens stored at room temperature on d 42, which were significantly lighter than the eggs from vitamin E- and thyme-fed hens (p 0.001). Relative egg weight loss was significantly higher (p 0.001) when stored at room temperature than under refrigeration, independently of storage time. In eggs stored at room temperature, yolk TBARS values were significantly lower (p 0.001) in the eggs of vitamin E-fed hens, whereas no influence (p>0.05) of dietary treatment on yolk TBARS values were detected in refrigerated eggs. The inclusion of the synthetic and both natural antioxidants in layer diets significantly reduced stearic acid (C18: 0) level in the egg yolk. In addition, only natural antioxidants significantly increased yolk levels of palmitoleic acid (C16: 1) and vaccenic acid (C18: 1n7). The results of the present study showed that adequate storage temperature was more effective in improving egg shelf life than feeding layers synthetic or natural antioxidant additives. However, the positive effects of the evaluated natural antioxidants on yolk fatty acid composition suggest their supplementation to layer diets may provide health benefits to the consumer.(AU)

Effect of Dietary Inclusion of Sodium Bicarbonate on Digestibility of Nutrients and Immune Response in Caged Layers During the Summer

The aim of this project was to investigate the effect of dietary inclusion of sodium bicarbonate (NaHCO3) on nutrient digestibility and immune response of caged layers during summer when the temperature exceeds 40 C. For immune response trial, White Leghorn layers (n=160; 24 weeks old) were purchased from a poultry farm and were divided into five treatment/diets groups (4 replicate/treatment). Diet A, was without NaHCO3 and served as control whereas, diets B, C, D, and E contained 0.5, 1.0, 1.5 and 2.0% NaHCO3, respectively. All these birds were vaccinated against Newcastle disease (ND) virus at the start of the experiment and thereafter with one-month intervals. Blood samples were collected from two birds/replicate at 10 days post vaccination each time to check antibody titer against ND virus. For digestibility trial, fecal samples were collected (6 layers/treatment group) at the start of the 37th week of age for two days, at 3 hours interval. Results revealed that immune response against ND virus 10 days post vaccination after 1st, 2nd and 3rd month was significantly (p 0.05) higher in layer birds fed diets containing NaHCO3. Digestibility of dry matter (DM), crude protein (CP), crude fiber (CF), ether extract (EE) and absorption of minerals were also found to be significantly (p 0.05) higher in groups treated with NaHCO3 and the birds fed diet containing 1% NaHCO3 showed the best results. In general, results revealed that 1% supplementation of NaHCO3 in layers diet have a beneficial impact in terms of immunity and diet digestibility.

Inhibitory Effects of Some Flavonoids on Thioredoxin Reductase Purified from Chicken Liver

Thioredoxin reductases (TrxRs) are selenocysteine-containing flavoenzymes that reduce Trxin NADPH-dependent manner. In the view of the direct vital role of TrxR in a wide range of biochemical and physiological processes, methods to inhibit this enzyme are clinically important. TrxR has recently emerged as a new candidate in anticancer drug investigations because of overexpression in tumorous cells. In this study, TrxR from chick liver was purified 94.6-fold with a yield of 4.86% and a specific activity of 0.19 EU/mg. KM and Vmax values of TrxR for DTNB were calculated as 0.9 mM and 0,03 EU/mL, respectively. Then, the effects of the flavonoids hesperidin, naringenin, chlorogenic acid, ferulic acid, naringin, 3,4-dihydoxybenzoic acid, and ellagic acid on the enzyme activity were evaluated under in-vitro conditions. Ellagic acid showed the strongest inhibitory activity on TrxR with a IC50 value of 18 µM, followed by naringenin and chlorogenic acid with IC50 values of 46.7 µM and 75.8 µM, respectively. Our results showed that flavonoids as natural products are potential inhibitors of TrxRs and the flavonoid content in animal diets may alter metabolic pathways by influencing TrxR activity.

Effects of The Dietary Supplementation of Layer Diets with Natural and Synthetic Antioxidant Additives on Yolk Lipid Peroxidation and Fatty Acid Composition of Eggs Stored at Different Temperatures and Duration

In this study, the effects of the supplementation of natural and synthetic antioxidant additives in layer diets on egg weight loss, yolk lipid peroxidation (TBARS values) and fatty acid composition of eggs stored at different temperatures and duration were evaluated. In total, 112 48- weeks-old Bovans White layers were randomly allotted to four dietary treatments with four replicates of seven birds each. The treatments consisted of a control diet, containing no additives, and diets with the inclusion of 200 mg synthetic vitamin E/kg, 1000 mg thyme extract/kg and 1000 mg rosemary extract/kg. Dietary treatments did not influence (p>0.05) relative weight loss of eggs stored for 14, 28, and 56 days, except for those from rosemary-fed hens stored at room temperature on d 42, which were significantly lighter than the eggs from vitamin E- and thyme-fed hens (p 0.001). Relative egg weight loss was significantly higher (p 0.001) when stored at room temperature than under refrigeration, independently of storage time. In eggs stored at room temperature, yolk TBARS values were significantly lower (p 0.001) in the eggs of vitamin E-fed hens, whereas no influence (p>0.05) of dietary treatment on yolk TBARS values were detected in refrigerated eggs. The inclusion of the synthetic and both natural antioxidants in layer diets significantly reduced stearic acid (C18: 0) level in the egg yolk. In addition, only natural antioxidants significantly increased yolk levels of palmitoleic acid (C16: 1) and vaccenic acid (C18: 1n7). The results of the present study showed that adequate storage temperature was more effective in improving egg shelf life than feeding layers synthetic or natural antioxidant additives. However, the positive effects of the evaluated natural antioxidants on yolk fatty acid composition suggest their supplementation to layer diets may provide health benefits to the consumer.

The effects of using garlic extract for quail hatching egg disinfection on hatching results and performance

This experiment was carried out to determine the effects of using garlic extract (Allium sativum) as an alternative to formaldehyde for the disinfection of hatching eggs on hatching traits and growth performance of quails. Four treatments, with 240 hatching eggs each, were evaluated: egg immersion in two different levels (2.5% and 5.0%) of garlic extract (garlic-1, garlic-2), formaldehyde fumigation (positive control), and eggs not submitted to disinfection (negative control). Mid-term and late embryomortality, pipped egg, and culled chick rates were not influenced by the (p>0.05). The highest (p<0.05) early embryo mortality rate was detected in the formaldehyde treatment (9.99%), and the lowest in garlic-2 treatment (2.68%). Hatchability of fertile eggs was the lowest in the formaldehyde group (83.78%), followed by the control (85.20%), garlic-1 (87.11%) and garlic-2 (88.72%) groups, respectively. The highest final body weight (5 weeks of age) was obtained in the garlic-2 group (304.1 g), followed by the control (294.13 g), formaldehyde (290.56 g), and garlic-1 (288.44 g), respectively, and the differences were statistically significant (p<0.05). Feed intake and feed conversion ratio were not influenced by the treatments (p>0.05). The results obtained for hatching traits and live performance parameters indicated that the immersion of eggs in garlic extract may be used as an alternative to formaldehyde fumigation for the disinfection of hatching quail eggs.(AU)

The effects of using garlic extract for quail hatching egg disinfection on hatching results and performance

This experiment was carried out to determine the effects of using garlic extract (Allium sativum) as an alternative to formaldehyde for the disinfection of hatching eggs on hatching traits and growth performance of quails. Four treatments, with 240 hatching eggs each, were evaluated: egg immersion in two different levels (2.5% and 5.0%) of garlic extract (garlic-1, garlic-2), formaldehyde fumigation (positive control), and eggs not submitted to disinfection (negative control). Mid-term and late embryomortality, pipped egg, and culled chick rates were not influenced by the (p>0.05). The highest (p0.05). The results obtained for hatching traits and live performance parameters indicated that the immersion of eggs in garlic extract may be used as an alternative to formaldehyde fumigation for the disinfection of hatching quail eggs.

Selected Traits of Hatched and Unhatched Eggs and Growth Performance of Yellow Japanese Quails

ABSTRACT This study was carried out to investigate selected traits of hatched and unhatched eggs and chick growth performance of yellow Japanese quails (Coturnix japonica). Eggshell temperature at the time of transfer to the hatcher was higher in hatched eggs (38.09oC) than in unhatched eggs (37.43oC) (p=0.000), lower in eggs with in early embryonic mortality (37.39oC) than those with late embryonic mortality (38.13oC) (p=0.000), and higher in eggs with female chicks (38.14oC) than those with male chicks (37.95oC). Lower eggshell, yolk, and albumen weights were determined in eggs with embryonic mortality of 17-18 days (0.58 g, 3.13 g and 4.96 g) compared with those with 10-16 days (0.67 g, 3.55 g and 5.58 g) and embryonic mortality of 1-9 days (0.75 g, 3.95 g and 6.19 g) (p=0.000). Lower egg weight loss was obtained in eggs with embryonic mortality (13.85%) of 1-9 days than those with embryonic mortality of 17-18 days (26.48%) (p=0.001). Females were heavier at chick weight (8.98 g vs. 8.63 g; p=0.033) and at 4 (231.81 g vs. 211.43 g; p 0.000) and 5(260.69 g vs. 231.87 g; p 0.000) weeks of age than males, and had longer left shanks (34.39 mm vs. 33.61 mm; p=0.004).(AU)

Selected Traits of Hatched and Unhatched Eggs and Growth Performance of Yellow Japanese Quails

ABSTRACT This study was carried out to investigate selected traits of hatched and unhatched eggs and chick growth performance of yellow Japanese quails (Coturnix japonica). Eggshell temperature at the time of transfer to the hatcher was higher in hatched eggs (38.09oC) than in unhatched eggs (37.43oC) (p=0.000), lower in eggs with in early embryonic mortality (37.39oC) than those with late embryonic mortality (38.13oC) (p=0.000), and higher in eggs with female chicks (38.14oC) than those with male chicks (37.95oC). Lower eggshell, yolk, and albumen weights were determined in eggs with embryonic mortality of 17-18 days (0.58 g, 3.13 g and 4.96 g) compared with those with 10-16 days (0.67 g, 3.55 g and 5.58 g) and embryonic mortality of 1-9 days (0.75 g, 3.95 g and 6.19 g) (p=0.000). Lower egg weight loss was obtained in eggs with embryonic mortality (13.85%) of 1-9 days than those with embryonic mortality of 17-18 days (26.48%) (p=0.001). Females were heavier at chick weight (8.98 g vs. 8.63 g; p=0.033) and at 4 (231.81 g vs. 211.43 g; p 0.000) and 5(260.69 g vs. 231.87 g; p 0.000) weeks of age than males, and had longer left shanks (34.39 mm vs. 33.61 mm; p=0.004).

Effect of Transient Treatment with Propylthiouracil on Some Reproduction Traits and Live Weight of Japanese Quails

This study was conducted to investigate the effects of transient treatment with propylthiouracil (PTU) on some reproduction traits and live weight of quails. The trial lasted 8 weeks. To accomplish this goal, 700 1-day-old quail chicks were used, randomly divided into 8 groups. PTU was added to feed by 0.1% and 0.5% /wt. The first 4 groups had 0.5% PTU at the age of 2-4, 4-6, 6-8 and 2-8 wk., respectively. The 5 th, 6 th and 7 th groups had 0.1% PTU at the age of 2-4, 4-6 and 6-8 wk., respectively, and the 8 th group was the control with no PTU. Quails were bled at 60 days of age. Then right and left testes were taken out and weighed. At the end of the trail, least square means of the live weight of the treatment groups were higher than the control (p 0.05). Similar results (p 0.05) were observed for testis weight, testis diameter and fertility rate. As a result, it can be said that the inclusion of PTU in quail rations positively affects the live weight and reproduction traits of quails.(AU)

Effect of Transient Treatment with Propylthiouracil on Some Reproduction Traits and Live Weight of Japanese Quails

This study was conducted to investigate the effects of transient treatment with propylthiouracil (PTU) on some reproduction traits and live weight of quails. The trial lasted 8 weeks. To accomplish this goal, 700 1-day-old quail chicks were used, randomly divided into 8 groups. PTU was added to feed by 0.1% and 0.5% /wt. The first 4 groups had 0.5% PTU at the age of 2-4, 4-6, 6-8 and 2-8 wk., respectively. The 5 th, 6 th and 7 th groups had 0.1% PTU at the age of 2-4, 4-6 and 6-8 wk., respectively, and the 8 th group was the control with no PTU. Quails were bled at 60 days of age. Then right and left testes were taken out and weighed. At the end of the trail, least square means of the live weight of the treatment groups were higher than the control (p 0.05). Similar results (p 0.05) were observed for testis weight, testis diameter and fertility rate. As a result, it can be said that the inclusion of PTU in quail rations positively affects the live weight and reproduction traits of quails.

Analyzing growth curves of turkeys reared in different breeding systems (intensive and free-range) with some nonlinear models

The objective of this study was to identify the growth curve of live weight of turkeys reared in different systems (intensive and free- range) with the best mathematical model. To achieve this goal, the live weight of male and female turkeys (Large White) reared for 0-18 weeks were used. Logistic, Gompertz, Von Bertalanffy, and Gauss were used to determine the best model for the turkeys. In comparison of the models, values of Coefficient of Determination (R2), Mean Squares of Error (MSE) and Model Efficiency (ME) were used. In Von Bertalanffy model, the coefficient of determinations for males and females were found as 0.9974 and 0.99915 in intensive system and 0.9794 and 0.9804 in Free-Range system, respectively. As a result of this study, because the highest R2 and the lowest MSE were observed in Von Bertalanffy model, it was the best among the models to identify growth curve of the turkeys.

Analyzing growth curves of turkeys reared in different breeding systems (intensive and free-range) with some nonlinear models

The objective of this study was to identify the growth curve of live weight of turkeys reared in different systems (intensive and free- range) with the best mathematical model. To achieve this goal, the live weight of male and female turkeys (Large White) reared for 0-18 weeks were used. Logistic, Gompertz, Von Bertalanffy, and Gauss were used to determine the best model for the turkeys. In comparison of the models, values of Coefficient of Determination (R2), Mean Squares of Error (MSE) and Model Efficiency (ME) were used. In Von Bertalanffy model, the coefficient of determinations for males and females were found as 0.9974 and 0.99915 in intensive system and 0.9794 and 0.9804 in Free-Range system, respectively. As a result of this study, because the highest R2 and the lowest MSE were observed in Von Bertalanffy model, it was the best among the models to identify growth curve of the turkeys.(AU)