Özge Altan

Effect of heat stress on oxidative stress, lipid peroxidation and some stress parameters in broilers

1. This study was conducted to determine the effects of heat stress on fearfulness, leucocyte components, oxidative stress and lipid peroxidation in two commercial broiler strains, Cobb (C) and Ross (R). 2. At 36 and 37 d of age birds were exposed to 38 ± 1°C for 3 h. Rectal temperatures, duration of tonic immobility (TI), haematocrit values, proportions of leucocyte components (heterophil, lymphocyte, basophil, eosinophil, monocyte), malondialdehyde (MDA) concentrations and antioxidant enzyme activities (CAT, SOD, GPx) of all the birds were determined, before and after heat treatment. 3. Rectal temperatures increased and haematocrit values decreased in birds exposed to heat stress. Heat stress caused a significant increase in heterophil/lymphocyte and in basophil ratios. 4. Exposing birds to heat stress increased duration of TI, suggesting heat-stressed birds tended to be more fearful. 5. Heat stress resulted in a significant Genotype × Treatment interaction for MDA concentration. CAT, SOD and GPx activities; MDA concentrations in heat-stressed R strain birds were greater than in heat-stressed C strain birds.

Effects of heat stress on growth, some blood variables and lipid oxidation in broilers exposed to high temperature at an early age.

1. This study was conducted to determine metabolic and physiological responses of 2 commercial broiler strains, Hubbard (H) and Cobb (C), exposed to an ambient temperature of 38°±1°C for 2 h at 14 and 15 d of age. 2. Exposure to high temperature at an early age resulted in weight loss in strain C, which was not compensated for by 35 d of age but there was no weight loss in strain H. 3. Exposure of broilers to heat stress (38°±1°C) at 35 d of age resulted in an increase in rectal temperature, regardless of previously high temperature experience but acid-base balance and haematocrit values were not affected by heat stress. 4. Malondialdehyde concentration was higher in unexposed birds than in previously exposed ones and did not significantly differ between strains.

The effect of short-term fasting on performance traits and rectal temperature of broilers during the summer season.

1. The present study was conducted to determine if detrimental effects of high temperature on broiler performance could be overcome by short-term fasting and to examine the effect of food withdrawal on the responses of two commercial strains (S1 and S2). 2. An experimental design was used with three feeding groups and two strains. Birds in the control (C) group were fed ad libitum during the experimental period (0 to 6 weeks), while feed was withdrawn in the other groups between 10:00 and 16:00 h during weeks 5 and 6 (F1) or week 6 (F2), respectively. After standard brooding for the first 3 weeks temperature and humidity varied according to outside climate between 4 and 6 weeks of age. 3. Feeding strategy significantly affected body weight at week 6 (BW6) and daily weight gain during week 6 (DWG5-6). F2 gave the best results in BW6 and DWG5-6. Strain effect was significant on DWG4-5 and DWG5-6; S1 had higher DWG4-5 and S2 gained more at the last stage. S1C broilers had greater BW6 than S2C but the S2 strain gave a better response to short-term fasting compared with S1 and this resulted in significant strain by feeding interaction effect on BW6 and DWG5-6. 4. It was shown that short-term fasting was an effective method for controlling rectal temperature (RT) of broilers at 5 and 6 weeks of age. 5. Total food consumption (FC0-6), food conversion ratio (FCR0-6), mortality, and carcase characteristics were not affected by short-term fasting in the experimental conditions. 6. In conclusion, it can be recommended that broiler producers may practise 6 h of fasting during the hot period of the day without any adverse effect on slaughter weight and FCR when the birds are close to the average slaughter weight and a heat wave is expected. Strain differences in RT measurements also indicate the importance of choosing strains to be used in hot and warm climate conditions with attention to the thermoregulation ability of broilers.

Body weights, carcase characteristics, organ weights, abdominal fat, and lipid content of liver and carcase in two lines of Japanese quail (Coturnix coturnix japonica), unselected and selected for four week body weight

1. The present study was conducted on quails to evaluate the effects of line and sex on body weight, carcase characteristics and organ weights and also to evaluate the effect of line on sex organs, and on carcase and liver lipid content of male quails. 2. Chicks of both sexes were weighed weekly until 6 weeks when they were slaughtered. Carcase yield, parts yield and measurement, weight of liver, heart, gizzard, abdominal fat and sex organs were obtained. Carcase and liver lipid content of male quails were determined. 3. Weights of body, carcase, breast, thigh, liver, heart, gizzard, abdominal fat, tests and ovary, yield of testes were affected by line. Line had no significant effect on the yields of carcase, breast, thigh, liver, heart, gizzard plus heart plus liver, abdominal fat and ovary. Carcase and liver lipid contents of male quails were affected by line.

Effects of some egg characteristics on the mass loss and hatchability of ostrich (Struthio camelus) eggs

1. This study was conducted to examine some egg characteristics and determine the effects of eggshell thickness and eggshell porosity on water loss and hatchability of eggs in ostriches. 2. Shell thickness did not correlate significantly with hatchability. However, eggs of low shell thickness lost more mass (13·03%) than those with intermediate (11·22%) and high (10·36%) shell thickness. Mass loss during incubation was higher in hatched (11·98%) than unhatched eggs (11·09%). Shell thickness was negatively correlated to egg mass loss (r = −0·65). 3. The pore density was correlated with hatchability. Hatchability was 50% lower in eggs with low pore densities (40·93%) than with high densities (80·94%). Pore density was positively correlated with egg mass loss (r = 0·63). Incubation mass losses of hatched and unhatched eggs were not significantly different. 4. Mean eggshell water vapour conductance (G) value and shell conductance constant (k) were 87·77 ± 4·21 mg H2O/d/Torr and 2·44 respectively (n = 15). 5. Because of eggshell functional properties and resulting low egg mass loss hatchability is low when ostrich eggs are artificially incubated. The mass of eggs used in the experiment was relatively high and their eggshell water vapour conductance was low. As a result, egg incubation mass loss was lower than it should be. It is concluded that incubator humidity should be low (25%) to allow enough mass loss during incubation from the eggs.

The effects of moderately oxidised dietary oil with or without vitamin E supplementation on performance, nutrient digestibility, some blood traits, lipid peroxidation and antioxidant defence of male broilers

BACKGROUND The experiment was conducted to determine the effects of dietary supplementation of oxidised oil with or without vitamin E on performance, nutrient digestibility, some blood traits, lipid peroxidation and antioxidant defence system of male broilers. RESULTS The supplementation of oxidised oil with or without vitamin E to the grower diets did not significantly affect performance, the pH and viscosity values of excreta and nutrient digestibilities in male broilers. Oxidised oil supplementation slightly increased plasma triglyceride and cholesterol concentrations but did not alter plasma glucose concentration. Although malondialdehyde (MDA) and nitric oxide concentrations tended to be higher in the oxidised oil group, these increases were not significant. Birds fed the diet containing oxidised oil had significantly lower superoxide dismutase (SOD) activity. However, no differences were observed in glutathione peroxidase (GSH-Px) activity and uric acid concentrations of broilers fed oxidised oil as compared to the control group. Dietary vitamin E supplementation decreased MDA concentration whereas increasing SOD activity, suggesting that vitamin E supplementation reduced susceptibility to lipid peroxidation. CONCLUSION The results showed that a milder oxidative stress occurred by supplementation of moderately oxidised oil to the diet of broilers and vitamin E supplementation had been helpful in alleviating lipid peroxidation.

Carcass Characteristics and Carcass Composition in Lines of Japanese Quail (Coturnix coturnix japonica), Unselected and Selected for Four-Week Body Weight

Abstract Oguz, I., Akbas, Y., Kirkpinar, F. and Altan, O. 1999. Carcass characteristics and carcass composition in lines of Japanese quail (Coturnix coturnix japonica) unselected and selected for four-week body weight. J. Appl. Anim. Res., 15: 175–180. The present study was conducted to evaluate the effects of line and sex on carcass characteristics and carcass composition in Japanese quail. At 6 week, chicks of both sexes were weighed and slaughtered. The weights of carcass and, yields, breast and thigh were obtained which were greater for S-line than those for C-line. Dry matter, crude protein, lipid and ash of carcass were determined. Line had no significant effect on carcass percentage, breast and thigh per cent yields and carcass composition parameters. Sex had significant effect on slaughter and breast weights while not on other weights and, percentage of carcass and, yields. There were significant differences between sexes in carcass composition traits except ash content.

Effect of Honey Treatment on Some Quality Characteristics of Broiler Breast Meat

Abstract Yücel, B., Önenç, A., Bayraktar, H., Açikgöz, Z. and Altan, Ö. 2005. Effect of honey treatment on some quality characteristics of broiler breast meat. J. Appl. Anim. Res., 28: 53–56. Breast meats of 12 broilers (Ross-308) were used to determine the effect of marination with honey water mixture (0, 20, 30% v/v) on their meat quality and bacterial activity. Treated meats were preserved at 4C for 7 days in vacuume. Drip loss, pH level and marinate uptake did not change significantly in breast meats marinated with different levels of honey and without honey. Marination with honey did not significantly affect the L*(brightness) and a*(redness) values of breast meats on 1st and 7th days of treatment. However, b* (yellowness) values were significantly affected by honey treatment. After 7th day, no significant differences were obtained for tenderness, flavor and acceptability between treatment and the control groups. Breast meats marinated with honey showed a slight decrease in bacterial number compared to control group after 4th day. It is indicated that honey marination might be considered as a means of limiting bacterial growth in broiler meat without any adverse effect on meat quality and sensory characteristics.

Relationship of Body Weight at Sexual Maturity with Body Weights at Various Ages in Lines of Japanese Quail (Coturnix coturnix japonica), Unselected and Selected for Four-Week Body Weight

Abstract Oğuz, I., Akbaş, Y. and Altan, Ö. 2001. Relationship of body weight at sexual maturity with body weights at various ages in lines of Japanese quail (Coturnix coturnix japonica), unselected and selected for four-week body weight. J. Appl. Anim. Res., 19: 219–223. To evaluate the relationship between body weights at sexual maturity and at various ages in two lines of Japanese quail, unselected and selected for four-week body weight for ten generation, body weights of female quails were measured at different days. Selection for increased 4-week body weight resulted in changes in weights at various ages and increased the body weight at sexual maturity. In two lines, correlations between body weights at various ages and body weight at sexual maturity, and regression of body weight at various ages on weight at the sexual maturity were generally positive and significantly different from zero. Selection for increased 4-week body weight in Japanese quail resulted in a delay in age at sexual maturity and body weights at sexual maturity were highly related to juvenile body weights in both Japanese quail lines.