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Öğe Acclimation to Heat During Incubation: 3. Body Weight, Cloacal Temperatures, and Blood Acid-Base Balance in Broilers Exposed to Daily High Temperatures(Poultry Science Assoc Inc, 2008) Yalcin, S.; Cabuk, M.; Bruggeman, V.; Babacanoglu, E.; Buyse, J.; Decuypere, E.; Siegel, P. B.The aim of the present study was to investigate the effects of parental age and heat acclimation during incubation on BW, cloacal temperature, and blood acid-base balance in fast-growing broilers exposed to daily cyclic high ambient temperatures from 21 to 42 d posthatch. Eggs obtained from 32- (younger), 42- (middle-aged), and 65-wk-old (older) breeders were divided into 2 groups. One group of eggs was incubated at the control incubation temperature (IT(CONT)) and the second group was heat acclimated at 38.5 degrees C for 6 h/d from d 10 to 18 of incubation (IT(HA)). Chicks were reared at standard brooding temperatures from d 1 to 21. From d 21 to 42, half of the broilers per incubation temperature and parental age were kept as controls (AT(CONT)) and the other half were exposed to daily cyclic heat treatment (AT(HIGH)) to impose a stress response. The reduction in BW at AT(HIGH) was more pronounced for progeny from older compared with younger parents. However, this reduction in BW was more or less abolished for broilers from eggs incubated at IT(HIGH), implying an increased tolerance to heat stress. Compared with IT(CONT), IT(HA) reduced BW of broilers from 32- and 42-wk-old parents while having no effect on those from 65-wk-old parents when reared at AT(CONT). Higher blood pH, and lower partial pressure CO(2) and HCO(3)(-) at AT(HIGH) were associated with greater cloacal temperatures throughout the heat stress from d 21 to 42. Increases in cloacal temperature by AT(HIGH) were greater for IT(CONT) than for IT(HA) broilers. The AT(HIGH) and IT(HA) broilers had lesser blood partial pressure CO2 concentrations than AT(CONT) and IT(CONT), respectively. Although at AT(HIGH), blood HCO(3)(-) was lower for broilers from all parental ages, it was more pronounced for those from 65-wk-old parents. It is concluded that these changes in blood acid-base balance reflected adaptive responses to heat stress, and incubating eggs at IT(HA) improved thermotolerance of fast-growing broilers.Öğe Acclimation to heat during incubation: 4. Blood hormones and metabolites in broilers exposed to daily high temperatures(Oxford Univ Press, 2009) Yalcin, S.; Bruggeman, V.; Buyse, J.; Decuypere, E.; Cabuk, M.; Siegel, P. B.The objective of the present experiment was to study the effects of parental age and heat acclimation of embryos on blood metabolites and hormones of broilers exposed to daily cyclic ambient temperatures from d 21 to 42. Eggs obtained from 32 (younger), 42 (middle-aged), and 65 wk (older) breeders were divided into 2 groups. One group of eggs was incubated at control incubation temperature (ITCONT), whereas the second group was heat-acclimated at 38.5 degrees C for 6 h/d from d 10 to 18 of incubation (ITHA). Chicks were reared at standard brooding temperatures from 1 to 21 d. From d 21 to 42, half of broilers/incubation temperature/parental age was kept as the control (AT(CONT)), whereas the other half was exposed to daily cyclic heat treatment (AT(HIGH)) to impose a stress response. There was a reduction in plasma triiodothyronine (T-3) levels in ITHA broilers. On d 28, plasma T-3 levels were similar regardless of parental age of eggs incubated at ITCONT, whereas ITHA resulted in lower levels of T-3 in broilers from 65 wk parents. At the same age, AT(HIGH) reduced plasma triglycerides with the effect greater for ITHA than ITCONT broilers. Plasma uric acid was also lower for ITHA than ITCONT broilers for the offspring of 65 wk parents on d 28. There was an increase in plasma creatine kinase activity on d 42 in AT(HIGH) broilers regardless of parental age and incubation temperature. Plasma corticosterone was consistently lower for the ITHA than ITCONT treatment, being significant on d 21 and 42. It was concluded that these changes in blood metabolites and hormones may enhance the thermoregulatory ability of ITHA broilers when exposed posthatch to daily high temperatures.Öğe Acclimation to heat during incubation: 4. Blood hormones and metabolites in broilers exposed to daily high temperatures(Oxford Univ Press, 2009) Yalcin, S.; Bruggeman, V.; Buyse, J.; Decuypere, E.; Cabuk, M.; Siegel, P. B.The objective of the present experiment was to study the effects of parental age and heat acclimation of embryos on blood metabolites and hormones of broilers exposed to daily cyclic ambient temperatures from d 21 to 42. Eggs obtained from 32 (younger), 42 (middle-aged), and 65 wk (older) breeders were divided into 2 groups. One group of eggs was incubated at control incubation temperature (ITCONT), whereas the second group was heat-acclimated at 38.5 degrees C for 6 h/d from d 10 to 18 of incubation (ITHA). Chicks were reared at standard brooding temperatures from 1 to 21 d. From d 21 to 42, half of broilers/incubation temperature/parental age was kept as the control (AT(CONT)), whereas the other half was exposed to daily cyclic heat treatment (AT(HIGH)) to impose a stress response. There was a reduction in plasma triiodothyronine (T-3) levels in ITHA broilers. On d 28, plasma T-3 levels were similar regardless of parental age of eggs incubated at ITCONT, whereas ITHA resulted in lower levels of T-3 in broilers from 65 wk parents. At the same age, AT(HIGH) reduced plasma triglycerides with the effect greater for ITHA than ITCONT broilers. Plasma uric acid was also lower for ITHA than ITCONT broilers for the offspring of 65 wk parents on d 28. There was an increase in plasma creatine kinase activity on d 42 in AT(HIGH) broilers regardless of parental age and incubation temperature. Plasma corticosterone was consistently lower for the ITHA than ITCONT treatment, being significant on d 21 and 42. It was concluded that these changes in blood metabolites and hormones may enhance the thermoregulatory ability of ITHA broilers when exposed posthatch to daily high temperatures.Öğe The association between sociodemographic parameters and the use of complementary interventions in patients with cancer in Turkey: A Turkish Oncology Group study.(Amer Soc Clinical Oncology, 2011) Turhal, N. S.; Kilickap, S.; Yalcin, S.; Sezgin, C.; Yamac, D.; Akbulut, H.; Ozyilkan, O.; Ozdemir, F.; Cabuk, D.; Sevinc, A.Öğe Bevacizumab plus capecitabine as maintenance treatment after initial treatment with bevacizumab plus XELOX in previously untreated metastatic colorectal cancer: Updated findings from a randomized, multicenter phase III trial(Amer Soc Clinical Oncology, 2011) Yalcin, S.; Uslu, R.; Dane, F.; Yilmaz, U.; Zengin, N.; Buyukunal, E.; Buyukberber, S.; Camci, C.; Sencan, O.; Kilickap, S.Öğe Broilers respond to cooler ambient temperatures after temperature acclimation during incubation and early postnatal age(Poultry Science Assoc Inc, 2013) Aksit, M.; Yalcin, S.; Siegel, P. B.; Yenisey, C.; Ozdemir, D.; Ozkan, S.Temperature acclimation, either during the incubation or the early growing period, has been suggested as an effective method to improve thermotolerance of broilers to cooler rearing temperatures. We compared the response of broilers from younger (Y) and older (O) breeder flocks to cooler rearing temperatures after temperature acclimation during incubation and early posthatch. Eggs were exposed to either a control incubation temperature (37.6 degrees C) or a cooler temperature (36.6 degrees C; ITcool) for 6 h (from 1000 to 1600 h) daily from d 10 to 18 of incubation. From d 22 to 42, chicks were reared at a control temperature (RTcont), a cooler temperature (17 +/- 2 degrees C; RTcool), or at a cooler temperature after acclimation of chicks to cooler temperatures by exposing them to 17 +/- 2 degrees C for 6 h on d 5 posthatch. The ITcool conditions reduced mortality and mortality due to ascites of O broilers reared under cooler temperatures from d 22 to 42. Early age acclimation to cooler temperatures did not support thermotolerance of broilers. Regardless of IT, the RTcool broilers from Y gained more weight but had poorer feed conversion than RTcont. Repeated cooler temperatures applied during incubation and early postnatal stage disturbed homeostasis and energy balance of broilers from O breeders.Öğe Dietary vitamin E (alpha-tocopherol acetate) and selenium supplementation from different sources: performance, ascites-related variables and antioxidant status in broilers reared at low and optimum temperatures(Taylor & Francis Ltd, 2007) Oezkan, S.; Malayoglu, H. Basmacioglu; Yalcin, S.; Karadas, F.; Koctuerk, S.; Cabuk, M.; Oktay, G.; Oezdemir, S.; Oezdemir, E.; Erguel, M.1. This study compared the effect of dietary supplementation with organic or inorganic selenium (Se) sources plus control amounts or large amounts of vitamin E (alpha- tocopherol acetate) in broilers raised at control ( 20 to 24 degrees C) or low ( 14 center dot 5 to 16 center dot 8 degrees C) temperatures after 2 weeks of age. 2. The following dietary treatments were used from one day old. Diet 1, the control diet, comprised a commercial diet containing 0 center dot 15 mg/ kg inorganic Se and 50 mg vitamin E/kg feed. Diet 2 was the same as diet 1, supplemented with 0 center dot 15 mg/ kg inorganic Se. Diet 3 was the same as diet 2 but was supplemented with 200 mg/ kg vitamin E. Diet 4 was the same as diet 1, but inorganic Se was replaced with 0 center dot 30 mg/ kg organic Se. Diet 5 was the same as diet 4, supplemented with 200 mg/ kg vitamin E. 3. Low temperature reduced the growth rate of broilers; however, at 6 weeks, there were no differences in the body weights of birds fed on organic Se supplemented diets housed at low or control temperature. The feed conversion ratio was significantly affected by low temperature but not by diet. The heterophil/ lymphocyte ratio was higher in chicks after one week in the cold, indicating mild stress. Blood triiodothyronine levels were significantly higher in birds after 1 and 4 weeks in the cold but thyroxin was not affected. 4. Organic Se supplementation increased relative lung weight at the control temperature, which might lead to greater respiratory capacity. Relative spleen weight significantly decreased in broilers fed diets supplemented with inorganic Se under cold conditions, a possible indication of chronic oxidative stress. 5. At the low temperature, supplementation with organic Se alone, or with inorganic Se and vitamin E increased glutathione peroxidase ( GSHPx) activity and glutathione ( GSH) concentration in the liver of broilers, which may indicate increased activity of birds' antioxidant defence against suboptimal environments.Öğe Effect of breeder age and lighting regimen on growth performance, organ weights, villus development, and bursa of fabricius histological structure in broiler chickens(Czech Academy Agricultural Sciences, 2015) El Sabry, M. I.; Yalcin, S.; Turgay-Izzetoglu, G.This study was carried out to investigate the effect of breeder age and lighting regimen on performance, some organ weights, villus development, and bursa of fabricius histological structure in broiler chickens. A total of 384 one-day-old chicks were obtained from two Ross broiler breeder flocks at 32 (young; Y) and 49 (old, O) weeks of age. Chicks from each breeder age were reared under 18 h light : 6 h dark (18 L : 6 D) (control; CL) or 14 L : 4 D : 2 L : 4 D (split darkness, SD). Body weight, feed intake, feed conversion ratio, and mortality were measured weekly during the experiment. At 21 days of age, liver, heart, spleen, and bursa of fabricius weights were recorded, gastrointestinal tract and jejunum lengths were measured, and histomorphometry of villi and bursa of fabricius structure were investigated. Interaction between breeder age and lighting regimen was observed, where Y-CL chicks had the lightest body weight from 7 to 35 days (P < 0.05). Neither breeder age nor lighting regimen influenced feed conversion ratio. SD chicks had longer (P < 0.05) gastrointestinal tract and jejunum, and wider villus in comparison to CL chicks. Lower relative spleen weight was observed in CL chicks compared to SD ones (P < 0.05). It was concluded that split darkness lighting regimen could be used for broiler chickens from young breeders to improve live body weight without affecting feed conversion ratio.Öğe Effect of egg storage duration and brooding temperatures on chick growth, intestine morphology and nutrient transporters(Cambridge Univ Press, 2017) Yalcin, S.; Gursel, I.; Bilgen, G.; Horuluoglu, B. H.; Gucluer, G.; Izzetoglu, G. T.The effects of egg storage duration (ESD) and brooding temperature (BT) on BW, intestine development and nutrient transporters of broiler chicks were investigated. A total of 396 chicks obtained from eggs stored at 18 degrees C for 3 days (ESD3-18 degrees C) or at 14 degrees C for 14 days (ESD14-14 degrees C) before incubation were exposed to three BTs. Temperatures were initially set at 32 degrees C, 34 degrees C and 30 degrees C for control (BT-Cont), high (BT-High) and low (BT-Low) BTs, respectively. Brooding temperatures were decreased by 2 degrees C each at days 2, 7, 14 and 21. Body weight was measured at the day of hatch, 2, 7, 14, 21, 28 and 42. Cloacal temperatures of broilers were recorded from 1 to 14 days. Intestinal morphology and gene expression levels of H+-dependent peptide transporter (PepT1) and Na-dependent glucose (SGLT1) were evaluated on the day of hatch and 14. Cloacal temperatures of chicks were affected by BTs from days 1 to 8, being the lowest for BT-Low chicks. BT-High resulted in the heaviest BWs at 7 days, especially for ESD14-14 degrees C chicks. This result was consistent with longer villus and larger villus area of ESD14-14 degrees C chicks at BT-High conditions. From 14 days to slaughter age, BT had no effect on broiler weight. ESD3-18 degrees C chicks were heavier than ESD14-14 degrees C chicks up to 28 days. The PepT1 and SGLT1 expression levels were significantly higher in ESD3-18 degrees C chicks than ESD14-14 degrees C on the day of hatch. There was significant egg storage by BT interaction for PepT1 and SGLT1 transporters at day 14. ESD14-14 degrees C chicks had significantly higher expression of PepT1 and SGLT1 at BT-Low than those at BT-Cont. ESD14-14 degrees C chicks upregulated PepT1 gene expression 1.15 and 1.57-fold at BT-High and BT-Low, respectively, compared with BT-Cont, whereas PepT1 expression was downregulated 0.67 and 0.62-fold in ESD3-18 degrees C chicks at BT-High and BT-Low. These results indicated that pre-incubation egg storage conditions and BTs affected intestine morphology and PepT1 and SGLT1 nutrient transporters expression in broiler chicks.Öğe Effect of maternal corticosterone on utilisation of residual yolk sac fatty acids by developing broiler embryo(Taylor & Francis Ltd, 2011) Yalcin, S.; Bagdatlioglu, N.; Babacanoglu, E.1. Increased concentrations of maternal corticosterone are deposited into egg yolk under stress conditions. This experiment investigated the effect of maternal corticosterone on yolk and yolk sac fatty acid profiles of eggs and developing broiler embryos. 2. At 42 weeks of age, 200 broiler breeder females were randomly divided into two groups: maternal corticosterone (MC): 2 mg/hen/d of corticosterone dissolved in 1 mL of 99% ethanol and mixed in the individual daily feed for a 14 d period, and control: 1 mL of ethanol added to the individual daily feed. Hens were inseminated, and eggs were collected daily from d 3 of corticosterone feeding to d 14 and incubated. Fatty acid profiles of egg yolk and yolk sac were analysed before incubation and at 12, 14, 18 and 21 d of incubation. 3. Yolk corticosterone concentrations were greater in MC eggs. Before incubation, eggs from MC had lower DHA (22 : 6 n-3) but higher stearic (18 : 0) and dihomo-gamma linolenic (20 : 3 n-6 Cis 8,11,14) acid content compared with the control. 4. Higher concentrations of stearic (18 : 0), elaidic (18 : 1 tr n-9), eicosenoic (20 : 1 n-9), eicosadienoic (20 : 2 n-6), dihomo-gamma linoleic (20 : 3 n-6) and arachidonic (20 : 4 n-6) acids and lower concentrations of myristic (14 : 0), palmitoleic (16 : 1 n-7), linoleic (18 : 2 n-6) and DHA (22 : 6 n-3) were found at different periods of incubation in the residual yolk sac of MC than from controls. 5. The results suggest that the preferentially selective absorption of fatty acids is related to specific tissue requirements.Öğe Effect of prenatal temperature conditioning of laying hen embryos: Hatching, live performance and response to heat and cold stress during laying period(Pergamon-Elsevier Science Ltd, 2015) Kamanli, S.; Durmus, I.; Yalcin, S.; Yildirim, U.; Meral, O.This study was designed to determine the effect of prenatal temperature conditioning on hatching and live performance of laying chickens, and response to heat and cold stress during laying period. A total of 3600 eggs obtained from ATAK-S brown parent stock were incubated at control (37.5 degrees C, CONT-Inc), cyclic low (36.5 degrees C/6 h/d from 10 to 18 d of incubation, LOW-Inc) or high (38.5 degrees C/6 h/d from 10-18 d of incubation, HIGH-Inc) incubation temperatures. Hatched chicks per incubation temperature were reared under standard rearing conditions up to 26 wk. From 27 to 30 wk, hens from each incubation temperature were divided into 3 environmentally controlled rooms and reared at control (20 +/- 2 degrees C, CONT-Room), low (12 +/- 2 degrees C, COLDS) or high (32 +/- 2 degrees C, HEATS) temperatures. Hatching performance, body weight, egg production, and plasma triiodothyronine (T-3) and thyroxine (T-4) levels and oxidant and antioxidant activities were evaluated. The highest hatchability was for LOW-Inc chicks while HIGH-Inc chick had similar hatchability to CONT-Inc. There was no effect of incubation temperatures on plasma MDA, GSH-Px, activities and T-4 concentrations on day of hatch. LOW- Inc chicks had higher SOD activities and T-3 concentrations compared to the other groups. Although chick weight was similar among incubation temperature groups, CONT-Inc chicks were heavier than those cyclic incubation temperature groups until 12 wk of age. Incubation temperature had no effect on sexual maturity age and weight and egg production of laying hens. From 27 to 30 wk, regardless of incubation temperature, HEATS hens lost weight from day 0 to 10, had the highest cloacal temperatures and lowest feed consumption and egg production while COLDS hens had the lowest cloacal temperatures. At day 5, 14 level was higher in LOW-Inc hens at COLDS but it was higher in HIGH-Inc hens at HEATS compared to CONT-Inc. These data may suggest a modification in thyroid activity of hens that were conditioned during the incubation period. Moreover under COLDS condition, SOD production of LOW-Inc hens was higher than those of CONT- and HIGH-Inc hens indicating an induction in antioxidant enzyme activity. Nonetheless, prenatal temperature conditioning of laying hen embryos had no advantage on laying performance of hens under temperature stress conditions. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Effect of prenatal temperature conditioning of laying hen embryos: Hatching, live performance and response to heat and cold stress during laying period(Pergamon-Elsevier Science Ltd, 2015) Kamanli, S.; Durmus, I.; Yalcin, S.; Yildirim, U.; Meral, O.This study was designed to determine the effect of prenatal temperature conditioning on hatching and live performance of laying chickens, and response to heat and cold stress during laying period. A total of 3600 eggs obtained from ATAK-S brown parent stock were incubated at control (37.5 degrees C, CONT-Inc), cyclic low (36.5 degrees C/6 h/d from 10 to 18 d of incubation, LOW-Inc) or high (38.5 degrees C/6 h/d from 10-18 d of incubation, HIGH-Inc) incubation temperatures. Hatched chicks per incubation temperature were reared under standard rearing conditions up to 26 wk. From 27 to 30 wk, hens from each incubation temperature were divided into 3 environmentally controlled rooms and reared at control (20 +/- 2 degrees C, CONT-Room), low (12 +/- 2 degrees C, COLDS) or high (32 +/- 2 degrees C, HEATS) temperatures. Hatching performance, body weight, egg production, and plasma triiodothyronine (T-3) and thyroxine (T-4) levels and oxidant and antioxidant activities were evaluated. The highest hatchability was for LOW-Inc chicks while HIGH-Inc chick had similar hatchability to CONT-Inc. There was no effect of incubation temperatures on plasma MDA, GSH-Px, activities and T-4 concentrations on day of hatch. LOW- Inc chicks had higher SOD activities and T-3 concentrations compared to the other groups. Although chick weight was similar among incubation temperature groups, CONT-Inc chicks were heavier than those cyclic incubation temperature groups until 12 wk of age. Incubation temperature had no effect on sexual maturity age and weight and egg production of laying hens. From 27 to 30 wk, regardless of incubation temperature, HEATS hens lost weight from day 0 to 10, had the highest cloacal temperatures and lowest feed consumption and egg production while COLDS hens had the lowest cloacal temperatures. At day 5, 14 level was higher in LOW-Inc hens at COLDS but it was higher in HIGH-Inc hens at HEATS compared to CONT-Inc. These data may suggest a modification in thyroid activity of hens that were conditioned during the incubation period. Moreover under COLDS condition, SOD production of LOW-Inc hens was higher than those of CONT- and HIGH-Inc hens indicating an induction in antioxidant enzyme activity. Nonetheless, prenatal temperature conditioning of laying hen embryos had no advantage on laying performance of hens under temperature stress conditions. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Effect of prenatal temperature conditioning of laying hen embryos: Hatching, live performance and response to heat and cold stress during laying period(Pergamon-Elsevier Science Ltd, 2015) Kamanli, S.; Durmus, I.; Yalcin, S.; Yildirim, U.; Meral, O.This study was designed to determine the effect of prenatal temperature conditioning on hatching and live performance of laying chickens, and response to heat and cold stress during laying period. A total of 3600 eggs obtained from ATAK-S brown parent stock were incubated at control (37.5 degrees C, CONT-Inc), cyclic low (36.5 degrees C/6 h/d from 10 to 18 d of incubation, LOW-Inc) or high (38.5 degrees C/6 h/d from 10-18 d of incubation, HIGH-Inc) incubation temperatures. Hatched chicks per incubation temperature were reared under standard rearing conditions up to 26 wk. From 27 to 30 wk, hens from each incubation temperature were divided into 3 environmentally controlled rooms and reared at control (20 +/- 2 degrees C, CONT-Room), low (12 +/- 2 degrees C, COLDS) or high (32 +/- 2 degrees C, HEATS) temperatures. Hatching performance, body weight, egg production, and plasma triiodothyronine (T-3) and thyroxine (T-4) levels and oxidant and antioxidant activities were evaluated. The highest hatchability was for LOW-Inc chicks while HIGH-Inc chick had similar hatchability to CONT-Inc. There was no effect of incubation temperatures on plasma MDA, GSH-Px, activities and T-4 concentrations on day of hatch. LOW- Inc chicks had higher SOD activities and T-3 concentrations compared to the other groups. Although chick weight was similar among incubation temperature groups, CONT-Inc chicks were heavier than those cyclic incubation temperature groups until 12 wk of age. Incubation temperature had no effect on sexual maturity age and weight and egg production of laying hens. From 27 to 30 wk, regardless of incubation temperature, HEATS hens lost weight from day 0 to 10, had the highest cloacal temperatures and lowest feed consumption and egg production while COLDS hens had the lowest cloacal temperatures. At day 5, 14 level was higher in LOW-Inc hens at COLDS but it was higher in HIGH-Inc hens at HEATS compared to CONT-Inc. These data may suggest a modification in thyroid activity of hens that were conditioned during the incubation period. Moreover under COLDS condition, SOD production of LOW-Inc hens was higher than those of CONT- and HIGH-Inc hens indicating an induction in antioxidant enzyme activity. Nonetheless, prenatal temperature conditioning of laying hen embryos had no advantage on laying performance of hens under temperature stress conditions. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Effect of source and concentration of dietary selenium on laying performance of egg-type breeders and antioxidant status of their offspring under delayed post- hatch feeding(Eugen Ulmer Gmbh Co, 2020) Kahraman, Z.; Yenice, E.; Goger, H.; Kamanli, S.; Gultekin, M.; Unay, E.; Yalcin, S.The present study aimed to evaluate the effect of dietary organic or inorganic selenium (Se) supplementation on laying and hatching performance, egg Se content and liver glutathione peroxidase (GSH-Px) concentration of eggtype breeders as well as their offspring antioxidant status under 36 h post-hatch feed withdrawal. Two hundred and seventy white egg-type breeders were used. the hens were randomly assigned to five dietary treatments. the basal diet contained no supplemental Se (Control). the four treatment groups consisted of two selenium sources (inorganic and organic, Se-inorg and Se-org, respectively) and two selenium levels (0.20 and 0.35 mg Se/kg diet). the total analysed Se concentration in the diets was between 0.137 and 0.138 mg/kg for Control, while it was 0.342 and 0.340 mg/kg for 0.20 Se-inorg, 0.339 and 0.351 mg/kg for 0.20 Se-org, 0.485 and 0.489 mg/kg for 0.35 Se-inorg, 0.481 and 0.495 mg/kg for 0.35 Se-org from 21 to 40 and 41 to 49 weeks, respectively. There was no effect of diets on laying performance, egg quality, and hatchability. Dietary Se supplementation increased egg Se content compared to Control, being higher in eggs from hens fed Se-org than those from hens fed Se-inorg. Liver GSH-Px activity of hens fed 0.35 mg Se/kg was higher than in hens fed 0.20 mg/kg Se. on d of hatch and 36 h post-hatch, residual yolk sac Se content of chicks from hens fed 0.35 mg Se/kg was higher than that of chicks from hens fed 0.20 mg/kg Se. After 36 h post-hatch feed withdrawal, plasma and liver GSH-Px activity of chicks from Se groups were higher than in chicks from the Control. It was concluded that dietary maternal Se would provide a protective mechanism for day-old chicks for coping with stressful situations exposed after hatching.Öğe Effect of temperature during the incubation period on tibial growth plate chondrocyte differentiation and the incidence of tibial dyschondroplasia(Oxford Univ Press, 2007) Yalcin, S.; Molayoglu, H. B.; Baka, M.; Genin, O.; Pines, M.Tibial dyschondroplasia (TD) is one of the most prevalent skeletal abnormalities in avian species, causing enormous economic losses and major animal welfare problems. Irregular cell differentiation of the chondrocytes that populate the growth plate has been hypothesized to be involved in the etiology of the disease. We evaluated the effect of incubation temperature at various stages of embryo development and bone formation on growth plate chondrocyte differentiation and the incidence of TD. Eggs were incubated either at a control temperature of 37.8 degrees C, or at 36.9 or 39 degrees C, each for 6 h/ d, during early (0 to 8 d) or late (10 to 18 d) embryo development. At 14 d of incubation and at hatch, tibias were collected and weighed, and their ash and calcium contents were determined. Growth plate chondrocyte differentiation was evaluated by alkaline phosphatase activity and collagen type 11 and osteopontin gene expression. In addition, the level of the heat-shock protein 90 (Hsp90) was evaluated by immunohistochemistry. The rest of the chicks were raised to 49 d and the incidence of TD was recorded. The incidence of TD increased only when the temperature was altered at the early stages of embryo development, and it was correlated with an increase in tibia ash but not with tibia weight or calcium content. Moreover, increased TD incidence was correlated with delayed chondrocyte differentiation. Early changes in incubation temperature caused an increase in the level of Hsp90 in articular and differentiated chondrocytes of the hypertrophic zone and in the numbers of distinct undifferentiated chondrocytes arranged in columns in the proliferative zone of the growth plate. In summary, the early stages of embryo development and bone formation are of utmost importantance for appropriate growth plate chondrocyte differentiation, and any temperature deviation will increase the subsequent incidence of TD. The increase in TD incidence is probably the result of delayed Hsp90-driven chondrocyte differentiation, supporting the hypothesis that TD is the result of abnormal chondrocyte differentiation.Öğe Effect of temperature manipulation during incubation on body weight, plasma parameters, muscle histology, and expression of myogenic genes in breast muscle of embryos and broiler chickens from two commercial strains(Taylor & Francis Ltd, 2022) Yalcin, S.; Aksit, M.; Ozkan, S.; Hassanzadeh, M.; Bilgen, G.; Helva, I. B.; Izzetoglu, G. T.1. This study evaluated the effect of a higher incubation temperature on body weight, plasma profile, histology and expression of myogenin (MYOG), insulin-like growth factor-I (IGF-I) and vascular endothelial growth factor A (VEGFA) genes in breast muscle of embryos and broilers from two commercial strains. 2. A total of 784 eggs from Ross 308 and Cobb 500 broiler breeder flocks were used. Half of the eggs per strain were incubated at control temperature (37.8 degrees C), whereas the other half were exposed to heat treatment (HT) of 38.8 degrees C between embryonic day (ED) 10 and 14, for 6 h/day. Embryos and chicks were sampled on ED 19 and at hatch. A total of 480, one-day-old chicks per strain and incubation temperature were reared up to 42 d post-hatch. 3. The HT increased hatch weight of Ross chicks and 42-d body weight of broilers from both strains. Lower plasma triacylglycerol levels were measured for HT embryos and broilers on ED 19 and 42 d post-hatch, respectively. HT reduced plasma T-3 levels in Ross embryos and broilers for the same periods. Hepatic TBARS concentrations were elevated by HT compared to the control incubation. 4. The HT reduced breast muscle VEGFA gene expression of Cobb embryos on ED 19, whereas expression was stimulated in day-old chicks. At 42 d post-hatch, fibre area was increased by HT regardless of strain. Compared to the control incubation, HT increased the breast yield of Ross broilers and leg yield of Cobb. Ross-HT broilers had a higher pH at 24 h after slaughter and better water holding capacity than Cobb-HT broilers. 5. These results suggested that HT increased body weight, fibre area, IGF-I gene expression and lowered plasma triacylglycerol levels of broiler chickens from both strains at 42 d. However, HT influenced the expression of VEGF-A and MYOG genes and meat quality differently between the broiler strains.Öğe Effects of breeder age and egg weight on morphological changes in the small intestine of chicks during the hatch window(Taylor & Francis Ltd, 2013) Yalcin, S.; Izzetoglu, G. T.; Aktas, A.1. The objective of the study was to investigate the effects of breeder age and egg weight on hatching performance and morphological changes in segments of the small intestine of broiler chicks during a 21 h hatch window.2. Eggs from Ross broiler breeder flocks aged 29 (young) and 48 weeks (old) were classified as light (LE) or heavy (HE) and incubated at the same conditions. At 475h of incubation, eggs were checked every 3h to determine time of external pipping and hatching. The first 42 chicks to emerge from each group were weighed and chick length was measured and 14 chicks from each group were sampled to collect residual yolk and intestine segments. The rest of chicks were placed back in the incubator and chick weight and length were measured individually at 9, 15 and 21h after chicks hatched. At the end of 21h, 14 chicks from each group were sampled again and the same procedure was followed.3. The HE chicks pipped and hatched later than LE, regardless of breeder age. From hatch to the end of the hatch window, chick weight, but not yolk-free chick weight, gradually reduced. Relative residual yolk weight of chicks from both egg weights was similar at hatch, however, yolk sac utilisation was higher for LE chicks during the 21 h post-hatch period. At hatch, jejunum and ileum villus development was very similar for HE and LE chicks but greater development was observed for villus area with an increase in the jejunum villus length, width and goblet cell numbers in HE chicks.4. The longest jejunum villus and the widest duodenum and jejunum villus were obtained for HE chicks from old breeders indicating that HE chicks from old breeders would have a greater surface area for nutrient absorption.Öğe Effects of enhancing vitamin D status by 25-hydroxycholecalciferol supplementation, alone or in combination with calcium and phosphorus, on sternum mineralisation and breast meat quality in broilers(Taylor & Francis Ltd, 2017) Bozkurt, M.; Yalcin, S.; Kocer, B.; Tuzun, A. E.; Aksit, H.; Ozkan, S.; Uygun, M.; Ege, G.; Guven, G.; Yildiz, O.1. The aim of the present study was to examine the effects of improving vitamin D status in broiler diets by supplementary 25-hydroxycholecalciferol (25OHD(3)), alone or in combination with calcium (Ca) and available phosphorus (aP), on live performance, sternum mineralisation and breast meat quality in broilers. 2. A total of 936 1-d-old Ross 308 broilers were used in the study. After gender determination at the hatchery, chicks from each sex were randomly distributed into three dietary treatments. The following dietary treatments were used in the experiment from hatch to 38 d: (1) A control diet formulated to meet all of the nutrient requirements of broiler chicks according to the management guide; (2) The control diet supplemented with 18.7-15.0 mu g/kg of 25OHD(3); and (3) The control diet supplemented with 18.7-15.0 mu g/kg of 25OHD(3) plus Ca + aP. 3. Improvement in vitamin D status by 25OHD(3) supplementation, alone or in combination with Ca and aP, had no effect on body weight and feed conversion ratio of broilers. 4. The serum 25OHD(3) concentration significantly increased with 25OHD(3) and 25OHD(3) plus Ca + aP supplementation (P < 0.05), whereas the ionised Ca and Mg concentrations remained unchanged. 5. Sternum absolute weight, ash content and the concentrations of Ca and P significantly increased (P < 0.01) with supplementation of 25OHD(3), alone or in combination with Ca + aP. 6. Supplemental 25OHD(3), alone or in combination with Ca + aP, slightly increased pH(24) (P = 0.05) and decreased (P < 0.01) squeezable water loss in breast meat, whereas it had no significant effect on lightness, yellowness and sarcoplasmic protein solubility. 7. In conclusion, the results suggested that enhancing vitamin D status by 25OHD(3) supplementation alone or in combination with Ca + aP may improve sternum structure and mineral accretion. Furthermore, supplemental 25OHD(3), even in a nutritionally complete diet, may offer an effective way to improve protein solubility in female broilers.Öğe Effects of monochromatic light on growth performance, welfare and hormone levels in broiler chickens(Eugen Ulmer Gmbh Co, 2019) Helva, I. B.; Aksit, M.; Yalcin, S.This study aimed to investigate the effect of the colour of monochromic light-emitting diode (LED) lighting on growth performance, tonic immobility duration, gait score, and hormone concentration in broilers. A total of 540 one-day-old broilers were randomly assigned into three lighting treatments: 1) 517-623 nm, 6500 K (white, WL), 2) 440 -480 nm (blue, BL), and 3) 503-540 nm (green, GL) LED light. Body weight and feed intake were recorded, weekly. The duration of tonic immobility and the gait score of the broilers were determined at d 28 and 35. Concentrations of growth hormone (GH), adrenocorticotropic hormone (ACTH) and insulin-like growth factor (IGF-1) were assayed on d 1, 7, 21 and 42. From d 14 to 42 broilers of the BL and GL groups were heavier than of the WL group. Although, there was no effect of lighting treatment on feed intake from d 0 to 21, GL and BL broilers consumed more feed than WL broilers from d 22 to 42. The duration of tonic immobility was not influenced by the LED light colour. Sex had a significant effect on tonic immobility duration. It was shorter in males than in females. There was no difference among groups in gait score at d 28. However, a better walking ability was obtained under GL on d 35. The WL broilers had the highest IGF-1 concentration on d 7. On d 42, birds under BL and GL lighting had lower ACTH concentration than under WL. The present results suggested that BL and GL improved body weight and reduced stress response of broilers. Furthermore, walking ability of broilers can be improved by GL lighting.Öğe Effects of temperature during rearing and crating on stress parameters and meat quality of broilers(Oxford Univ Press, 2006) Aksit, M.; Yalcin, S.; Ozkan, S.; Metin, K.; Ozdemir, D.Two trials were conducted to study the effects of heat stress during rearing (trial 1) and crating (trial 2) on broiler stress parameters and fear, breast meat quality, and nutrient composition. The relationships between stress parameters and meat quality traits were also determined. Trial I consisted of 3 temperature treatments from 3 to 7 wk: control (temperature was 22 degrees C); diurnal cyclic temperature (temperature was 28 degrees C from 1000 to 1700 h and 22 degrees C from 1700 to 1000 h); and constant high temperature (34 degrees C; temperature was 34 degrees C). In trial 2, broilers from the control and 34 degrees C groups in trial I were used. Broilers in each group were placed in transport cages. The 9 cages from the control group were divided into 3 groups and placed into 3 rooms at 15, 22, or 34 degrees C for 2 h. The 3 cages from the 34 degrees C group were also held in the room at WC (34-34 degrees C). Diurnal cyclic temperature had no effect on BW up to 5 wk of age. The effect of WC constant temperature on BW of broilers increased with age. Plasma levels of glucose and albumin increased by 34 degrees C, but no dramatic change in levels occurred when those broilers were crated at 34 degrees C. The heterophil:lymphocyte (H:L) was higher for the 34-34 degrees C broilers and the control broilers in the WC room than those from the 22 and 15 degrees C room. Breast muscle glycogen level decreased in broilers reared under diurnal cyclic or high temperatures. A lower pH and higher lightness (L*) and redness values and redness:yellowness were found in meat for broilers from both 34 degrees C and 34-34 degrees C groups. Higher H:L was associated with breast muscle pH according to first-order polynomial regression. The H:L had a significant effect on L* values, which were described by a second-order polynomial regression. Blood glucose level was positively correlated with L* and redness values. Duratiori of tonic immobility was neither influenced by rearing and crating temperatures nor associated with meat quality parameters.
