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1.
1. An experiment was conducted to determine the effect of different dietary protein contents on the performance of naked neck (Na/na) and normally feathered (na/na) broilers.

2. Chicks from the two genotypes were reared in wire‐floored cages and divided at random into 3 groups. Birds were fed on high protein (HP, 12.99 MJ ME, 238 g crude protein/kg and 12.94 MJ ME, 216 g crude protein/kg from 0 to 3 and 3 to 7 weeks, respectively), medium protein (MP, 12.99 MJ ME, 219 g crude protein/kg and 12.87 MJ ME, 201 g crude protein/kg from 0 to 3 and 3 to 7 weeks), and low protein (LP, 12.94 MJ ME, 205 g crude protein/kg and 12.75 MJ ME, 184 g protein/kg from 0 to 3 and 3 to 7 weeks) diets.

3. The LP diets resulted in a significantly lower daily body weight gain of males from 0 to 3 weeks. Dietary protein content had no effect on body weight gain from 3 to 7 weeks, body weight at 7 weeks, and the food intake of birds. Carcase composition of birds from both genotypes was unaffected by dietary protein.

4. Naked neck birds had significandy higher body weights at 7 weeks. Yields of carcase and breast of Na/na males were significantly higher than those of na/na males. There were no significant differences between females from the two genotypes as regards carcase yield.

5. It was concluded that the dietary protein requirements of naked neck birds were similar to those for normally feathered birds.  相似文献   

2.
High-pressure liquid chromatography (HPLC) was used to determine the capsaicin, dihydrocapsaicin, and total capsaicinoids levels of different ground red pepper samples obtained from local retail markets in Izmir, Turkey. Scoville scores were determined using sensory tests. An electronic nose (EN) was used to discriminate ground red pepper samples by headspace volatiles. EN data were analyzed using discriminant function analysis (DFA). An overall correct classification rate of pepper varieties by EN of 91% was obtained. A linear correlation between capsaicin, dihydrocapsaicin, and total capsaicinoids and Scoville scores was also observed, and R (2) values of 0.89, 0.85, and 0.91 were obtained, respectively.  相似文献   
3.
Essential oils of peppermint Mentha piperita L. (Lamiaceae), which are used in flavors, fragrances, and pharmaceuticals, were investigated for their antimicrobial properties against 21 human and plant pathogenic microorganisms. The bioactivity of the oils menthol and menthone was compared using the combination of in vitro techniques such as microdilution, agar diffusion, and bioautography. It was shown that all of the peppermint oils screened strongly inhibited plant pathogenic microorganisms, whereas human pathogens were only moderately inhibited. Chemical compositions of the oils were analyzed by GC and GC/MS. Using the bioautography assay, menthol was found to be responsible for the antimicrobial activity of these oils.  相似文献   
4.
The effects of months of the year and nitrogen (N) sources on salad rocket (Eruca sativa Mill.) yield, quality, and nitrate accumulation was investigated during the years 2002 and 2003. In both years, seeds were sown on the first day of April, May, June, July, August and September. Three different nitrogen sources were used: farmyard (cattle) manure (100 tonnes·ha?1), calcium nitrate [Ca(NO3)2]-15.5% N (150 kg N·ha?1) and ammonium sulfate [(NH4)2SO4)]-21% N (150 kg N·ha?1). Yield, leaf color, dry matter, vitamin C and total glucosinolate content and nitrate accumulation was assessed. Growing months affected all the assessed parameters significantly both years, with the exception of hue angle in 2003, whereas nitrogen source only influenced yield and nitrate accumulation in 2003. In both years the highest yield was obtained in April, but vitamin C and total glucosinolate contents were higher during summer months, and leaves were slightly darker colored. Chemical fertilizers increased the yield compared to farmyard manure; however, they also increased nitrate accumulation slightly, without any significant difference between them. Nitrate accumulation never exceeded 300 mg kg?1 fresh weight (FW), which is well below the acceptable daily intake of 3.7 mg nitrate per kg?1 bodyweight set by European Commission's Scientific Committee on Food.  相似文献   
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6.
Redesigning IT systems for specific user groups encompasses a lot of effort with respect to analysing and understanding user behaviour. The goal of this paper is to provide insights into patterns of behaviour of agricultural users, during the usage of a decision support system called OPTIRas™. This system aids agricultural users in their cultivar selection activities. We analyse logs resulting from OPTIRas™, and we get insights into user’s navigational patterns. We claim that the results of our analysis can be used to support the redesign of decision support systems in order to address specific agricultural users’ characteristics.  相似文献   
7.
The current study investigated the effects of oyster mushroom Pleurotus ostreatus, extract on immunological and hematological parameters of rainbow trout, Oncorhynchus mykiss. The fish were fed diets containing 0 (control), 1, and 2% supplementation of the oyster mushroom extract for 6 wk. Blood samples were collected weekly for the first 6 weeks. After 6 wk of feeding, the fish were challenged with Lactococcus garvieae and mortality was recorded. The results of this study showed that feeding rainbow trout an oyster mushroom extract–supplemented diet stimulated phagocytic activity of phagocytic cells, lysozyme activity, and myeloperoxidase activity in serum, but it did not significantly affect the total serum immunoglobulin level. At the same time, a significant increase was found in the number of neutrophils, monocytes, and total white blood cells. Fish fed the diet supplemented with oyster mushroom extract showed reduced mortalities following L. garvieae infection compared with controls. These results show that supplementation of fish diets with oyster mushroom extract at 1 and 2% concentrations significantly imrpoves hematological parameters and modulates the immune response against L. garvieae in rainbow trout.  相似文献   
8.
Antibacterial activity of seed proteins of Robinia pseudoacacia   总被引:1,自引:0,他引:1  
A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.  相似文献   
9.
10.
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.  相似文献   
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