Browsing by Author "Yalçin S."
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Item Effects of interferon-α-2b and octreotide on healing of esophageal corrosive burns(2001) Kaygusuz I.; çelįk O.; Özkaya Ö.; Yalçin S.; Keleş E.; çetįnkaya T.Objective The aim of this study was to investigate the effect of interferon-α to 2b and octreotide on the treatment of esophagus corrosive burns. Method The experimental study was performed on 63 rabbits. Burn was obtained by treating a segment, isolated in cervical esophagus, with NAOH. The rabbits were allocated into three groups (control, interferon, and octreotide). On the fourth, eighth, and 20th days, 7 rabbits randomly selected from each group were killed. Comparisons among the groups were made by taking histopathologic findings, stenosis index, and hydroxyproline production into consideration. Cross-tabulation and analysis of variance tests were used for statistical analysis. Results There were no statistically significant differences among the groups in terms of epithelial changes, extension of inflammation, and severity of fibrosis. In terms of severity of inflammation, there was a statistically significant difference between the control and the other two groups. Also, a significant difference was found between the control group and the other two groups in terms of extension of fibrosis on the 20th day. The difference between the control and the two treatment groups was significant on the eighth day and the 20th day measurements. Comparison of the hydroxyproline values showed a statistically significant difference between the octreotide group and the other two groups on the eighth and 20th days. Conclusion Histopathologic and biochemical findings indicate that, by hindering fibrosis progress, octreotide (and interferon) might be new and promising alternatives in the treatment of corrosive burns of the esophagus. © 2001 The American Laryngological, Rhinological and Otalogical Society, Inc.Item Criteria for Evaluating Husbandry Practices to Alleviate Heat Stress in Broilers(Poultry Science Association, 2003) Yalçin S.; Özkan S.; Çabuk M.; Siegel P.B.This study was undertaken to investigate the effects of management techniques used under heat stress on growth as well as developmental instability, duration of tonic immobility (TI), and heterophil-to-lymphocyte ratios (H:L) of broilers. Three-hundred sixty cockerels obtained from a commercial hatchery were randomly assigned to 12 floor pens. When the cockerels reached 21 d of age, three pens were kept as controls. Broilers in the other nine pens were moved to a room heated from 32 to 35°C between 1000 and 1700 h each day from 21 to 42 d of age. Broilers in the heated room were randomized into three treatment groups consisting of 1) conditioned (chicks exposed to 36°C for 24 h at 5 d of age), 2) feed-restricted (during the heat stress, feed was withdrawn 2 h before the hot period, and chicks were fed between 1700 and 0800 h), 3) and heat-stressed only. Conditioned and feed-restricted broilers gained 3.2 and 2.8%, respectively, more BW than heat-stressed broilers. Relative asymmetry (RA) averaged across several bilateral traits for the prolonged heat stressor was more informative than the RA for a single bilateral trait. Corrrelations suggest that RA were not closely associated with duration of TI and H:L under the conditions of this experiment.Item Pre- and postnatal conditioning induced thermotolerance on body weight, physiological responses and relative asymmetry of broilers originating from young and old breeder flocks(Poultry Science Association, 2005) Yalçin S.; Özkan S.; Çabuk M.; Buyse J.; Decuypere E.; Siegel P.B.The present experiment was conducted to examine the effects of pre- and postnatal conditioning to induce thermotolerance in broilers hatching from eggs orginating from younger and older breeder flocks. From each flock, 500 eggs were randomly divided into 2 groups and incubated at standard (SIT) and high (HIT) temperatures. At hatch, chicks were allotted to 36 floor pens. At 5 d of age 3 pens per parent age per incubation temperature were heat conditioned (C) for 24 h. At 21 d of age, 3 pens per parent age per incubation temperature were kept under standard (S) rearing temperatures, whereas the remaining broilers (including C) were moved to a heated room (H). Thus, there were 3 groups from 21 to 49 d including S, H, and C+H. The results indicated that to incubate eggs from younger parents at HIT before conditioning at 5 d may reduce deleterious effects of heat stress on body weight at slaughter age. However, HIT temperature decreased slaughter weight of broilers from older parents regardless of rearing temperature. Although conditioning did not prevent increments in rectal temperatures of broilers after 1 wk of heat stress (28 d), adaptation occurred thereafter for broilers from younger parents but not for broilers from older parents. Incubation temperature had no effect on plasma glucose, creatine kinase, uric acid, or triiodotryronine (T3) levels at d 21. There were no differences at 22, 25, or 28 d for T3 concentrations between the H and C+H groups. Overall relative asymmetry was not influenced by treatments on d 49. The results suggest that although pre- and postnatal conditioning may help broilers cope with heat stress, age of parent plays a major role in the ability of broilers to thermoregulate. This is especially the case for broilers originating from younger parents. ©2005 Poultry Science Association, Inc.Item Dietary vitamin e (α-tocopherol acetate) and selenium supplementation from different sources: Performance, ascites-related variables and antioxidant status in broilers reared at low and optimum temperatures(2007) Özkan S.; Malayoǧlu H.B.; Yalçin S.; Karadaş F.; Koçtürk S.; Çabuk M.; Oktay G.; Özdemir S.; Özdemir E.; Ergül 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 (-tocopherol acetate) in broilers raised at control (20 to 24C) or low (145 to 168C) 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 015 mg/kg inorganic Se and 50 mg vitamin E/kg feed. Diet 2 was the same as diet 1, supplemented with 015 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 030 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.Item Acclimation to heat during incubation: 3. Body weight, cloacal temperatures, and blood acid-base balance in broilers exposed to daily high temperatures(Poultry Science Association, 2008) Yalçin S.; Çabuk M.; Bruggeman V.; Babacanoǧlu 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°C for 6 h/d from d 10 to 18 of incubation (ITHA). 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 (ATCONT) and the other half were exposed to daily cyclic heat treatment (ATHIGH) to impose a stress response. The reduction in BW at ATHIGH 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 ITHIGH, implying an increased tolerance to heat stress. Compared with ITCONT, ITHA 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 ATCONT. Higher blood pH, and lower partial pressure CO2 and HCO3- at ATHIGH 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 ITCONT than for ITHA broilers. The ATHIGH and ITHA broilers had lesser blood partial pressure CO2 concentrations than ATCONT and ITCONT, respectively. Although at ATHIGH, 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 ITHA improved thermotolerance of fast-growing broilers. ©2008 Poultry Science Association Inc.Item Acclimation to heat during incubation. 1. Embryonic morphological traits, blood biochemistry, and hatching performance(Poultry Science Association, 2008) Yalçin S.; Çabuk M.; Bruggeman V.; Babacanoǧlu E.; Buyse J.; Decuypere E.; Siegel P.B.Eggs obtained from broiler breeders at 32 (young), 42 (middle aged), and 65 wk (old) were used to measure the effects of heat acclimation during incubation on morphological, physiological, and metabolic traits at internal pipping (IP) and at hatch. All eggs were from the same stock, and hatching performance was also evaluated. Eggs from each breeder age were incubated at control (CONT) or 38.5°C for 6 h daily from d 10 to 18 of incubation (HA). On d 10 after heat exposure and on d 14, absolute and proportional weights were significantly lower for HA than CONT embryos. By the time of hatching, HA chicks were heavier than CONT chicks, which suggested accelerated growth. This effect was consistent across ages. Liver and heart weights were lower for HA than CONT chicks. At IP, pH was similar for HA and CONT embryos, whereas pO2 and Na + were significantly higher and pCO2, HCO3 ?, and K+ significantly lower for HA than CONT embryos. Blood pH was higher in embryos from older than for younger and mid-aged parents at IP. At hatch there was no effect of heat acclimation for blood HCO 3?, Na+, and K+ levels, whereas plasma triglyceride and T3 levels were higher and plasma uric acid, glucose, and lipid peroxidation levels were lower for HA than CONT chicks. Embryonic mortality was similar among parental ages for CONT. In contrast for HA, embryonic mortality from older parents was higher than for younger and middle-aged parents. A delay in external pipping and hatching time with high incubation temperature was consistent across the breeder ages. It was concluded that lower blood pCO2, HCO3?, K+, and higher pO2 at IP stage, plus increased plasma triglyceride concentrations at hatch, indicate adaptive responses of embryos. ©2008 Poultry Science Association Inc.Item Acclimation to heat during incubation. 2. Embryo composition and residual egg yolk sac fatty acid profiles in chicks(Poultry Science Association, 2008) Yalçin S.; Baǧdatlioǧlu N.; Bruggeman V.; Babacanoǧlu E.; Uysal I.; Buyse J.; Decuypere E.; Siegel P.B.The aim of the research was to evaluate embryo composition and changes in egg yolk fatty acid composition during embryonic development as a function of incubation temperature and age of breeders. Eggs obtained from a common breeder stock at 3 ages: 32 (younger), 42 (mid age), and 65 (older) wk were divided into 2 groups and placed into 2 incubators: the control and the second where eggs were heat-acclimated (HA) at 38.5°C for 6 h daily from d 10 to 18 of incubation. Body composition of embryos and chicks were measured on d 14, 18, and at hatch, respectively. Fatty acid profiles of yolk and residual egg yolk sac of chicks were analyzed before incubation and at hatch, respectively. Moisture content of embryos was highest on d 14 and then decreased regardless of parental age and incubation temperature. Moisture content of chicks at hatch from 42- and 65-wk parents were lower than those of chicks from 32-wk parents, whereas the trend in chick fat content was opposite. Incubation temperature had no effect on composition of chicks. Consistently lower cis-4,7,10,13,16,19- eicosapentaenoic (docosahexaenoic acid, DHA; 22:6n-3) and cis-11,14,17- eicosatrienoic (20:3n-3) fatty acids in the residual yolk sac of chicks than in egg yolks before incubation may have resulted from preferential uptake from the yolk. The DHA content in the residual yolk sac was considerably higher in chicks from older parents incubated at HA, whereas, in contrast, levels of 18:3n-3 were lower. Also, chicks from younger parents in the HA treatment had lower transported 18:3n-3 and higher levels of transported DHA. It may be concluded that this process observed during the high incubation temperature may be related to a protective strategy and thus contributes to postnatal heat adaptation. ©2008 Poultry Science Association Inc.Item Acclimation to heat during incubation: 4. Blood hormones and metabolites in broilers exposed to daily high temperatures(Poultry Science Association, 2009) Yalçin S.; Bruggeman V.; Buyse J.; Decuypere E.; Çabuk 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°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 (ATCONT), whereas the other half was exposed to daily cyclic heat treatment (ATHIGH) to impose a stress response. There was a reduction in plasma triiodothyronine (T3) levels in ITHA broilers. On d 28, plasma T3 levels were similar regardless of parental age of eggs incubated at ITCONT, whereas ITHA resulted in lower levels of T3 in broilers from 65 wk parents. At the same age, ATHIGH 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 ATHIGH 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. © 2009 Poultry Science Association Inc.Item Effect of maternal corticosterone on utilisation of residual yolk sac fatty acids by developing broiler embryo(2011) Yalçin S.; Baǧdatlioǧlu N.; Babacanoǧlu E.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 14d period, and control: 1mL 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. © 2011 British Poultry Science Ltd.Item Effect of manipulation of incubation temperature on fatty acid profiles and antioxidant enzyme activities in meat-type chicken embryos(Oxford University Press, 2012) Yalçin S.; Baǧdatlioǧlu N.; Yenisey C.; Siegel P.B.; Özkan S.; Akşit M.Eggs (n = 1,800) obtained from Ross broiler breeders at 32 and 48 wk of age were incubated at either a constant temperature of 37.6°C throughout (T1), or the temperature was reduced for 6 h to 36.6°C each day during embryonic age (EA) 10 to 18 (T2). Yolk sac, liver, and brain fatty acid profiles and oxidant and antioxidant status of liver and brain were measured at EA 14, 19, and day of hatch (DOH). Fatty acid profiles of yolk sac, liver, and brain were influenced by age of breeder with significant breeder hen age × incubation temperature interactions. At EA 14, higher levels of 20:4n-6 and 22:6n-3 had been transferred from the yolk sac to T2 embryos from younger than older breeders, whereas for T1 and T2 embryos, yolk sac 20:4n-6 and 22.6n-3 values were similar for older breeders. Accumulation of 20:4n-6 and 22:6n-3 fatty acids in the liver of T1 and T2 embryos from younger breeders was similar; however, T2 embryos from older breeders had higher liver levels of 20:4n-6 and 22:6n-3 than T1 embryos. At EA 19, liver nitric oxide levels were higher for T2 embryos from younger breeders than those from breeders incubated at T1. Brain catalase levels of T2 embryos from younger breeders were higher than those from older breeders at DOH. Thus, changes in fatty acid profiles and catalase and nitric oxide production of brain and liver tissues resulting from 1°C lower incubation temperature from EA 10 to 18 reflect adaptive changes.© 2012 Poultry Science Association Inc.