Gulcan Demirel

Genotype, production system and sex effects on fatty acid composition of meat from goat kids

Two trials were performed to assess the meat fatty acid profile of goat kids from different genotypes, production systems and sex. In the first trial, genotype effect was determined in 24 suckling male kids from Turkish Saanen, Maltese and Gokceada breeds. In the second trial, male and female Gokceada Goat kids were used to compare the effect of extensive and semi-intensive production systems on fatty acid composition of meat. Significant genotype effect was observed in the percentages of myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1 n-9), linolenic acid (C18:3 n-3), arachidonic acid (C20:4 n-6) and docosahexaenoic acid (C22:6 n-3), despite no differences on the ratios of polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) and n-6/n-3 (P > 0.05). The effect of production system had also significant effects on fatty acids, but sex only influenced significantly stearic acid (C18:0), C18:1 n-9 and C18:3 n-3 fatty acids and total PUFA level and PUFA/SFA ratio. This study confirms that dairy breeds are prone to produce higher levels of unsaturated fatty acids in their muscle. Meanwhile, meat from Gokceada goat kids, which is one of the indigenous breeds in Turkey, had similar PUFA/SFA and n-6/n-3 ratios to Turkish Saanen and Maltase.

Effects of dietary mannanoligosaccharide on performance, some blood parameters, IgG levels and antibody response of lambs to parenterally administered E. coli O157:H7

Abstract Forty-eight male lambs were used to evaluate the effect of dietary supplementation of mannan-oligosaccharide (MOS) with or without parenteral Escherichia coli injection on their growth performance, feed conversion efficiency, blood metabolites, total serum immunoglobulin G (IgG) levels and antibody response. Lambs were randomly assigned to four groups of 12 animals each. In groups C (control) and CE (E. coli challenged), animals were fed commercial concentrate pellets and hay (50:50), and in groups M (MOS) and ME (MOS+E. coli challenged), animals were fed commercial concentrate pellets including MOS at 0.2% and hay (50:50). At day 15 and 30, animals in groups CE and ME were injected subcutaneously with 1 ml of phosphate buffered saline (PBS) suspension containing 106 cfu of heat inactivated non-toxigenic E. coli O157:H7, while animals in C and M groups were injected subcutaneously with 1 ml of PBS. The experimental period was 45 days. Data indicated that body weight of lambs at the end of the study were statistically non-significant among the groups. Blood metabolites, i.e. total protein, albumin, calcium and phosphorus concentrations were not affected significantly by MOS supplementation. However, administration E. coli lowered (p < 0.05) total protein, albumin and calcium concentrations in the serum on day 30. The IgG level was not different between groups. However, on day 45, the total IgG level was found to be higher (p < 0.05) in lambs that had received MOS and E. coli than in other groups. Application of MOS did not have any effect on the antibody response to E. coli as OD values.

Comparison of broiler meat quality when fed diets supplemented with neutralized sunflower soapstock or soybean oil

The objective of the current study was to evaluate the effect of dietary fat type and level on broiler meat quality. A 2 × 3 factorial arrangement with 2 types of fat including neutralized sunflower soapstock (NSS) and soybean oil (SO) at 3 levels of fat inclusion (2, 4, and 6%) was used with 5 replicates per treatment using 750 one-day-old broiler chicks in a completely randomized design. At the end of the study (d 36), 10 broilers from each replication were processed at a commercial slaughtering facility. Six carcasses from each replicate were used for meat quality evaluation. With the exception of 3 responses [breast meat lightness (L*) at 1 and 2 d, and redness (a*) at 5 d], there were no interactions between fat source and level. Breast meat pH at 15 min was not significantly affected by the dietary treatments. However, breast meat pH at 24 h postmortem was decreased (P < 0.01) in broilers fed the NSS. Breast meat cooking loss, shear force, and color did not differ between fat sources. Breast meat cooking loss decreased (P < 0.05) when the dietary levels of fat increased. Thigh meat TBA reactive substances were not different due to dietary fat source and level. Breast meat and skin L* value significantly decreased when the dietary levels of fat increased. Breast meat a* value was highest for the 6% fat fed birds on d 2 (P < 0.05) and d 5 (P < 0.01). Higher dietary fat levels decreased the b* values of breast meat except d 5. Breast skin yellowness (b*) value was higher (P < 0.01) for the SO-fed birds compared with NSS-fed birds. Thigh meat of the birds fed the NSS was lighter (P < 0.05) than that of the birds fed SO diets except d 5. Overall, data suggest that NSS can be used as an alternative fat source to SO with little effect on meat quality.

Effect of starter cultures combinations on lipolytic activity and ripening of dry fermented sausages

The effect of starter culture combinations on the quality of Turkish type dry fermented sausage (sucuk) were evaluated during ripening and storage periods. Sucuk formulations were produced without (control) and with three different starter culture combinations; i) Staphylococcus carnosus+Pediococcus pentosaceus, ii) Staphylococcus carnosus+ Lactobacillus sakei, and iii) Staphylococcus carnosus+Pediococcus pentosaceus+ Lactobacillus sakei. Analysis of microbiological, physico-chemical and lipase enzyme levels of samples were conducted until the 60th day. Interactions among the presence of lipolytic starter cultures, lipase enzyme levels and thiobarbituric acid reactive substances were also evaluated both in ripening and drying periods. There were apparent differences on microbiological and chemical properties between samples prepared with starters and control. It has been concluded that the use of lipolytic starter cultures in suitable combination would have positive effect on the acceleration of ripening and improvement of the quality of dry fermented sausages.