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Öğe A Bayesian approach for describing the growth of Chukar partridges(EUGEN ULMER GMBH CO, 2019) Iqbal, F.; Eyduran, E.; Mikail, N.; Sariyel, V.; Huma, Z. E.; Aygun, A.; Keskin, I.In this article, a Bayesian approach was employed for estimating the body growth of Chukar partridge (Alectoris chukar). Nonlinear growth models commonly used to estimate the growth curve of birds were fitted to weight-age data and estimates of model parameters and their credible intervals were obtained via a formal Bayesian framework. More specifically, the Gompertz, Brody, Logistic and von Bertalanffy growth models were fitted to weekly body weight data of 108 female and 72 male partridge chicks from hatch to 20 weeks of age. Deviance Information Criteria (DIC) and the coefficient of determination (R-2) were employed as the goodness of fit for comparing the fitted models. The DIC and R-2 values of the models ranged from 172.9 to 204.2 and 0.9765 to 0.9913, respectively. The von Bertalanffy model was found to provide the best fit in terms of lower DIC and higher R-2 values, followed by the Gompertz model for both male and female partridge data. The Bayesian approach was found to be adequate for fitting complex nonlinear functions to weight-age data of Chukar partridges.Öğe Comparison of growth curve models in partridge(OXFORD UNIV PRESS, 2017) Sariyel, V.; Aygun, A.; Keskin, I.This study was conducted in order to determine the goodness of fit of Brody, Gompertz, Logistic, and von Bertalanffy growth curve models in partridge (Alectoris chukar). The growth curve parameters A (upper asymptote or mature weight parameter), B (scale parameter related to initial weight), and K (instantaneous growth rate parameter) were determined as 623.4, 1.05, and 0.075 for females and 723.8, 1.06, and 0.073 for males in the Brody model, respectively, 472.9, 3.47, and 0.207 for females and 565.3, 3.59, and 0.192 for males in the Gompertz model, respectively, 440.2, 12.89, and 0.332 for females and 517.0, 14.13, and 0.319 for males in the Logistic model, respectively, and 498.9, 0.77, and 0.164 for females and 608.8, 0.79, and 0.150 for males in the von Bertalanffy model, respec-tively. While determining which growth curve model presented the better fit, the coefficient of determination (R-2), adjusted the coefficient of determination (adj. R-2), mean square predicted error (MSPE), Durbin-Watson value, correlation between estimated live weight and residual values (RESC), Akaike's information criteria (AIC), and Bayesian information criterion (BIC) were used. As a consequence of the study, it was determined that the Gompertz model yields a better fit to the data for the partridge, as its coefficient of determination and adjusted coefficient of determination are high, its values of MSPE, RESC, AIC, BIC are low and there is not an autocorrelation between the residual values. As a result, the Gompertz model presented a better fit with the partridge data.Öğe Effect of Copper Supplementation on Performance, Eggshell Quality and Heterophil: Lymphocyte Ratio in Aged Laying Hens Housed at Different Stocking Densities(ANIMAL NUTRITION ASSOC, 2017) Olgun, O.; Aygun, A.This study was conducted to determine the effects of additional dietary copper on performance, eggshell quality and heterophil: lymphocyte ratio in aged laying hens housed at different stocking densities. For this purpose, 216 Nick Chick laying hens of 106 weeks of age, were housed at three different stocking densities i.e. 500, 417 and 357 cm(2)/hen, respectively and copper (0, 150 and 300 mg/kg) was added in the basal diet for a period of 10 weeks using a 3x3 factorial arrangement. The effect of the treatments on body weight gain, feed intake, damaged eggs, specific gravity and eggshell breaking strength were not significant (P>0.05). However, eggshell thickness was improved (P<0.05) with increasing stocking density in the aged laying hens. Additionally, added copper had a significant effect on egg production (P<0.05), egg weight (P<0.01), egg mass (P<0.01), feed conversion ratio (P<0.01) and eggshell weight (P<0.01). While added copper had a significant adverse effect on eggshell weight, the addition of copper had a significant positive effect on performance parameters. Highest stocking density resulted in increased (P<0.05) heterophil: lymphocyte ratio. Addition of 150 and 300 mg/kg copper in the diet of the birds kept at 500 cm(2)/hen stocking density reduced heterophil: lymphocyte ratio as compared to other groups. It may be concluded that supplementation copper in the diet of aged laying hens decreased stress under normal stocking density, while stress was increased to the birds under high stocking density.Öğe EFFECT OF TEMPERATURE ON FENTON OXIDATION OF YOUNG LANDFILL LEACHATE: KINETIC ASSESSMENT AND SLUDGE PROPERTIES(GLOBAL NETWORK ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2012) Aygun, A.; Yilmaz, T.; Nas, B.; Berktay, A.Treatment of young landfill leachate, collected from municipal solid waste site of city of Konya, was investigated by using the Fenton process. The leachate itself showed the characteristics of pH 7.25, COD 38.2 g L-1 and BOD5 22 g L-1. Ratio of BOD5 to COD with 0.58 indicates that leachate can be defined young. Fenton oxidation of landfill leachate was expressed in two-stage process, where a fast initial reaction (H2O2/Fe2+) was followed by a much slower one (H2O2/Fe3+). Overall kinetics can be described by a second-order rate equation followed by zero-order one. The kinetic studies were undertaken at the different temperatures and reaction rates increcesed by increasing temperature. The apparent kinetic constants at 303 K are k = 3.16 x 10(-3) L g(-1) min(-1) and k(0) = 0,171 g L-1 min(-1), respectively. Fenton reagents effectively degraded the leachate organics and most of the degradation was completed within 30 minutes for all temperatures. The performance of Fenton process was not only presented as a COD removal but also expressed as the amount of generated sludge and its properties. Sludge properties were revealed with Capillary Suction Time (CST) and Sludge Volume Index (SVI). The minimum CST value was obtained at the optimum molar ratio of 4.12 mol/mol and increasing temperature resulted in a positive effect on CST values. All SVI values were significantly low which indicates that sludge itself had good settling properties.Öğe Effects of force molting on eggshell colour, egg production and quality traits in laying hens(ECOLE NATIONALE VETERINAIRE TOULOUSE, 2013) Aygun, A.The objective of this study was to explore the effects of force molting on eggshell colour, egg production and quality traits in brown laying hens. Lohmann Brown Classic adult hens were randomly divided into 2 groups: the molted group (n = 38) was submitted to a 10 day long molt period (consuming only alfalfa) whereas control hens (n = 36) were fed with a standard layer diet during the whole experimental period. Eggs in pre-molt (4 weeks) and post-molt (12 weeks) periods were examined for egg production, quality traits and eggshell colours. Force molting induced significant weight loss in hens. Egg production was dropped since the 5th day of the molt period and started again at the 3rd week of the post-molt period for reaching initial egg production. Whereas no difference was evidenced between the 2 groups during the pre-molt period, the eggshell strength as well as the red chromaticity and the yellow chromaticity were significantly increased in eggs from the molted hens during the post-molt period. These results suggest that a molt period may improve some egg qualities.Öğe The Effects of In-Ovo Injection of Propolis on Egg Hatchability and Starter Live Performance of Japanese Quails(FACTA-FUNDACIO ARNCO CIENCIA TECNOLOGIA AVICOLAS, 2016) Aygun, A.The purpose of this study was to determine the effects of in-ovo injection of a propolis water extract on hatchability, embryonic mortality, starter live performance, and livability of Japanese quails. In total, 500 fresh hatching eggs were randomly distributed into five treatment groups of 100 eggs per treatment with four replicates of 25 eggs each. On day 14 of incubation, eggs from group 1 were not injected (control), group 2 was injected with distilled water (water), group 3 was injected with 1% propolis water extract (1% propolis), group 4 was injected with 2% propolis water extract (2% propolis), and group 5 was injected with 3% propolis water extract (3% propolis). A completely randomized design was applied, and data were analyzed using the least-square methodology. Hatchability and embryonic mortality in the 2% propolis and 3% propolis treatment groups were significantly lower compared with the control group, but no significant differences were observed between the 1% propolis and control groups. There were no significant bodyweight gain, feed intake, feed conversion ratio, or livability differences among treatments. The results of this study demonstrated that in-ovo injection of propolis water extract, especially at doses of 2% and 3% propolis, had negative effects on hatchability and embryonic mortality, but 1% propolis had no detrimental effects on hatchability or embryonic mortality. In all treatment groups, propolis did not negatively affect body weight gain, feed intake, feed conversion ratio, or livability.Öğe Effects of Propolis on Eggshell Microbial Activity, Hatchability, and Chick Performance in Japanese Quail (Coturnix Coturnix Japonica) Eggs(2012) Aygun, A.; Sert, D.; Copur, G.Propolis is a sticky resin produced by worker honeybees from substances collected from plants, and it has strong antibacterial and antifungal properties. The purpose of this study was to establish the effects of propolis on egg weight loss, hatchability, chick performance, and to control microbial activity naturally occurring on eggshells. A total of 750 fresh eggs was randomly divided into 5 groups. Eggs from the first group were sprayed with ethyl alcohol (70%, A), the second group was sprayed with benzalkonium chloride (B), and the third, fourth, and fifth groups were sprayed with propolis at 3 doses: 5, 10, and 15%. Eggs sprayed with propolis had lower egg weight loss than eggs from groups A and B (P < 0.001). Bacterial activity was reduced significantly in all propolis groups. There were no significant differences between treatments for hatchability, embryonic mortality, BW gain, and relative growth. Results of the present study indicated that propolis could be an alternative hatching egg disinfectant versus a chemical disinfectant, without adverse effects on hatchability and performance of quail chicks.Öğe Effects of ultrasonic treatment and storage temperature on egg quality(POULTRY SCIENCE ASSOC INC, 2011) Sert, D.; Aygun, A.; Demir, M. K.In this study, the effects of ultrasonic treatment and storage temperature on egg weight, specific gravity, shell strength, albumen height, Haugh unit, color, pH, water activity, total mesophilic aerobic bacteria, mineral content, and sensory properties were investigated. Ultrasonic treatment was used to improve egg properties. The lowest weight loss values were obtained with eggs treated with 15 min of ultrasonic treatment and stored at 5 degrees C for 10 d. The higher specific gravity, shell strength, albumen height, and Haugh unit were observed in ultrasonic-treated eggs. The egg quality was significantly improved with ultrasonic treatment (P < 0.01). The total mesophilic aerobic bacteria values of yolk and albumen decreased with increase in ultrasonic treatment time from 5 to 30 min. Ultrasonic treatment improved the sensory properties of egg shells.Öğe Effects of ultrasonic treatment on eggshell microbial activity, hatchability, tibia mineral content, and chick performance in Japanese quail (Coturnix coturnix japonica) eggs(POULTRY SCIENCE ASSOC INC, 2012) Aygun, A.; Sert, D.The purpose of this study was to establish the effects of ultrasonic treatment of eggs on egg weight loss, hatchability, tibia mineral content, chick performance, and eggshell microbial activity. A total of 600 fresh eggs was randomly divided into 5 groups. Treatments were no ultrasound, 35 kHz for 5 min, 35 kHz for 10 min, 35 kHz for 15 min, and eggs sprayed with benzalkonium chloride solution at 0.02% ( negative control). The eggshell microbial activity was reduced significantly at all ultrasonic treatments ( P < 0.01). There were no significant differences among treatments for egg weight loss, hatchability, embryonic mortality, chick weight, or tibia Ca, P, K, Na, and Mg content.Öğe Growth curve analyses in poultry science(CAMBRIDGE UNIV PRESS, 2017) Narinc, D.; Narinc, N. Oksuz; Aygun, A.Growth is a key characteristic of animals and can be defined as any change in body size per time unit, and is influenced by genotype and environment. Mathematical functions called 'growth models' have been used to explain the growth patterns of poultry species. These semi-mechanistic growth models have a non-linear structure, sigmoid shape, and certain biologically meaningful parameters. In poultry science, Gompertz, Logistic, Richards and von Bertalanffy functions have been commonly used to model the growth patterns of birds. In this review, the studies concerned have been summarised under the titles 'determination of the best-fitting growth model', 'a comparison of the growth of poultry species or various experimental groups', and 'genetic parameter estimates for growth curve parameters'. This review discusses existing and new approaches to growth modelling.Öğe Improving the Sludge Disintegration Efficiency of Sonication by Combining With Alkalization and Thermal Pre-Treatment Methods(Iwa Publishing, 2012) Sahinkaya, S.; Sevimli, M. F.; Aygun, A.One of the most serious problems encountered in biological wastewater treatment processes is the production of waste activated sludge (WAS). Sonication, which is an energy-intensive process, is the most powerful sludge pre-treatment method. Due to lack of information about the combined pretreatment methods of sonication, the combined pre-treatment methods were investigated and it was aimed to improve the disintegration efficiency of sonication by combining sonication with alkalization and thermal pre-treatment methods in this study. The process performances were evaluated based on the quantities of increases in soluble chemical oxygen demand (COD), protein and carbohydrate. The releases of soluble COD, carbohydrate and protein by the combined methods were higher than those by sonication, alkalization and thermal pre-treatment alone. Degrees of sludge disintegration in various options of sonication were in the following descending order: sono-alkalization > sonothermal pre-treatment > sonication. Therefore, it was determined that combining sonication with alkalization significantly improved the sludge disintegration and decreased the required energy to reach the same yield by sonication. In addition, effects on sludge settleability and dewaterability and kinetic mathematical modelling of pre-treatment performances of these methods were investigated. It was proven that the proposed model accurately predicted the efficiencies of ultrasonic pretreatment methods.Öğe Nutritional factors affecting the breaking strength of bone in laying hens(CAMBRIDGE UNIV PRESS, 2016) Olgun, O.; Aygun, A.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.Öğe Poultry semen cryopreservation technologies(CAMBRIDGE UNIV PRESS, 2018) Ciftci, H. B.; Aygun, A.Several techniques have been developed for the preservation and improvement of genetic resources to maintain genetic diversity. Among those techniques, semen cryopreservation is thought to be the best and successfully applied by dairy and beef industries, but so far, it has not been established in the poultry industry. This is because poultry sperm cells have a unique shape and membrane fluidity, differing from those of mammalian sperm. Also, poultry sperm membranes contain higher quantities of polyunsaturated fatty acids than mammalian sperm, and hence may require more antioxidant protection. Due to the peculiarity of poultry sperm cells, commonly used cryoprotectants for cryopreservation have a contraceptive or toxic effect. This renders the fertility of frozen poultry sperm to become highly variable and not reliable enough for use in commercial production or preservation of genetic resources. The average fertility of frozen/thawed poultry sperm ranges between 2-80%. Therefore, this paper reviews the possible reasons for the lower success of poultry sperm cryopreservation.Öğe Use of Humic Acid-based Nanofibers for Dye Removal and Transport(IEEE, 2017) Ayyildiz, H. F.; Ozcan, F.; Ertul, S.; Kara, H.; Aygun, A.A highly efficient nanofibrous adsorbent was prepared by using a mixture of humic acid (HA) and polyacrylonitrile (PAN) in DMF via electrospinning process, and the obtained nanofibrous adsorbent (PAN-HA) was used in copper removal. Owing to the incorporation of functional groups of HA, PAN nanofiber was turned into a material (PAN-HA) exhibiting anionic and cationic dye transfer. The prepared nanofiber mat was found to exhibit a suitable morphology according to the results of scanning electron microscopy, SEM, images. In this study, the removal and transport of HA-doped PAN nanofibers at different ratios (0-100%) at different pH and concentrations of methyl oranj, congo red, rodamin B and navy blue are carried out in a special membrane system. The results were evaluated in the design expert program.
