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101.
The effect of seawater exposure on the fracture toughness of balsa (Ochroma pyramidale L.) and end-grain balsa cores that are widely used in small-craft constructive members has been investigated experimentally in this study. The interfacial fracture toughness was determined using mode I cracked sandwich beam (CSB) tests. Additionally, the same tests were performed for poplar (Populus tremula L.), easily available because of its natural distribution along the coast of Turkey and more cost-effective than balsa and its derivatives, to see if it is a proper alternative. It was found that balsa and poplar cores that can be classified as low-density cores have much lower fracture toughness values than end-grain balsa cores. Additionally, there was a positive effect of seawater exposure on their fracture toughness as opposed to that of the end-grain core. From the aspect of fracture toughness, the poplar core can be considered much more reliable than the balsa core where delamination loads occur.  相似文献   
102.

Background

Bovine leukocyte adhesion deficiency (BLAD), deficiency of uridine monophosphate synthase (DUMPS), complex vertebral malformation (CVM), bovine citrullinaemia (BC) and factor XI deficiency (FXID) are autosomal recessive hereditary disorders, which have had significant economic impact on dairy cattle breeding worldwide. In this study, 350 Holstein cows reared in Turkey were screened for BLAD, DUMPS, CVM, BC and FXID genotypes to obtain an indication on the importance of these defects in Turkish Holsteins.

Methods

Genomic DNA was obtained from blood and the amplicons of BLAD, DUMPS, CVM, BC and FXID were obtained by using PCR. PCR products were digested with TaqI, AvaI and AvaII restriction enzymes for BLAD, DUMPS, and BC, respectively. These digested products and PCR product of FXID were analyzed by agarose gel electrophoresis stained with ethidium bromide. CVM genotypes were detected by DNA sequencing. Additionally, all genotypes were confirmed by DNA sequencing to determine whether there was a mutant allele or not.

Results

Fourteen BLAD, twelve CVM and four FXID carriers were found among the 350 Holstein cows examined, while carriers of DUMPS and BC were not detected. The mutant allele frequencies were calculated as 0.02, 0.017, and 0.006 for BLAD, CVM and FXID, respectively with corresponding carrier prevalence of 4.0% (BLAD), 3.4% (CVM) and 1.2% (FXID).

Conclusion

This study demonstrates that carriers of BLAD, CVM and FXID are present in the Turkish Holstein population, although at a low frequency. The actual number of clinical cases is unknown, but sporadic cases may appear. As artificial insemination is widely used in dairy cattle breeding, carriers of BLAD, CVM and FXID are likely present within the population of breeding sires. It is recommended to screen breeding sires for these defective genes in order to avoid an unwanted spread within the population.  相似文献   
103.
The study was conducted to determine the effect of feeding systems on fattening performance, slaughter, and carcass characteristics of male Norduz kids. In the study, 20 male Norduz kids weaned at 2.5 months of age were divided into two groups after weaning. The first group was reared under semi-intensive conditions (SI) on a mixture of pasture and concentrate, and the second group was reared under extensive conditions (E) on pasture only. SI group had higher final weight (35.30 kg versus 32.81 kg), daily weight gain (153.10 g versus 132.14 g), and warm carcass yield (44.84% versus 46.55%) compared to the E group although there were no significant differences. Body organs, carcass parts, prime cuts, and chemical composition of the chop area did not also differ in two groups significantly. As a conclusion, this study showed that semi-intensive feeding systems improved kid fattening performance and carcass characteristics.  相似文献   
104.
1.?The objective was to evaluate the effects of brooding temperature on intestinal development, oxidative organ damage, and performance of chicks acclimated to high temperature during incubation. The effects of acclimation and brooding temperatures on slaughter weights of broilers under heat stress were also investigated.

2.?Eggs were incubated at either 37?8°C (INCCont) or heat-acclimated at 39?5°C for 6 h daily from d 10 to d 18 of incubation (INCH). Brooding temperatures at floor level were set at 32, 33?5 and 35°C (Bt32, Bt33?5, Bt35, respectively) for the first 5 d. The temperature was reduced gradually to 30°C from d 6 to d 10. From 21 to 42 d, broilers from INCCont Bt32 and INCH Bt32 and Bt35 were divided into two groups; half from each group was exposed to daily cyclic higher ambient temperatures, while the other half was reared at control temperature.

3.?INCH chicks had lower jejunum, but greater liver and residual yolk sac weights than INCCont chicks on the day of hatching. Although INCH chicks from Bt33?5 and Bt35 had lighter body weights than Bt32 on d 5, no significant differences were observed in the body weight of broilers among treatments at 10 and 21 d.

4.?Similar jejunum protein, alkaline phosphatase, maltase, glutathione, and malondialdehyde contents of chicks from INCCont and INCH suggested that heat acclimation during incubation has no effect on jejunum enzyme activity or oxidative status of chicks.

5.?Taking into account INCH Bt35 chicks having lower T3 levels on d 5, lower heterophil/lymphocyte (H/L) ratios and similar weights at 42 d under heat stress compared with control broilers, the results suggested that although higher brooding temperatures had no effect on body weights of INCH chicks during the brooding period, those broilers may able to cope better with heat stress.  相似文献   

105.
This experiment was carried out in a mature (>100-year-old) eastern beech forest in the Eastern Black Sea Region (BSR) of Turkey. The effects of experimental practices to control the woody plant Rhododendron flavum Don., including grubbing, manual cutting, and foliar and cut-stump spraying with imazapyr and triclopyr, were assessed on understory and forest floor biomass and nutrients, as well as soil bulk density and nutrient content. The cut plots had 5, 15, and 38 times greater competing vegetation biomass than did the plots treated with triclopyr, grubbing, and imazapyr, respectively. Because of the increased biomass, the amount of understory N, P, Ca, K, S, and Mg content on the cut plots was also substantially higher when compared to the grubbed, imazapyr-treated, and triclopyr-treated plots. Triclopyr and imazapyr applications brought about two- and threefold greater dead organic matter on the forest floor than did cutting and grubbing, respectively. As a result, forest floor macronutrient contents on the imazapyr- and triclopyr-treated plots were significantly greater than on the cut plots. Five years after treatments, soil bulk density at the 10–20 cm depth on the imazapyr-sprayed plots was about 14% higher than that on other treatments. Herbicides, especially imazapyr and grubbing were effective in controlling rhododendron. Macronutrients stored in the rhododendron were released to the forest floor after vegetation was controlled with herbicides.  相似文献   
106.
The temporal and spatial distribution of Tomato spotted wilt virus (TSWV) was studied in a 2,085 m2 tomato field with a total of 4,080 plants during 10 weeks from 5 July to 6 September in 2004. First infected plants were detected 4 weeks after the source plants were placed in the field and their number continued to increase by week 7. A total of 147 plants (3.6%) were recorded to be infected according to symptom occurrence and serological test by the end of the experiment. Thrips monitoring was carried out from May 25 to October 25 in the same year. Two thrips species, Frankliniella intonsa (Tryborn) and Thrips tabaci (Lindemann), were determined in the experimental area, with the latter one being the more prevalent (84.9%) species. There was a significant correlation (r?=?0.988, P?<?0.01) between the number of thrips species and the number of infected plants in the field. Majority of infected plants were not located near (0–10 m) an internal virus source within the experimental area, whereas 45.6% of the infected plants were located at a distance of 21–30 m. The number of infected plants at a distance of 21–25 m was significantly higher than at all other distances (P?<?0.05). There was no gradual increase in the distances of TSWV-infected plants within 0–30 m as time progressed. The virus seems to be transmitted by vectors through primary infections and scattered within 30-m distance, but limited secondary infections seem likely to occur after this distance in the case of a small internal virus source.  相似文献   
107.
Human milk fat (HMF) analogue containing docosahexaenoic acid (DHA) and arachidonic acid (ARA) at sn-1,3 positions and palmitic acid (PA) at sn-2 position was produced. Novozym 435 lipase was used to produce palmitic acid-enriched hazelnut oil (EHO). EHO was then used to produce the final structured lipid (SL) through interesterification reactions using Lipozyme RM IM. Reaction variables for 3 h reactions were temperature, substrate mole ratio, and ARASCO/DHASCO (A:D) ratio. After statistical analysis of DHA, ARA, total PA, and PA content at sn-2 position, a large-scale production was performed at 60 °C, 3:2 A:D ratio, and 1:0.1 substrate mole ratio. For the SL, those results were determined as 57.3 ± 0.4%, 2.7 ± 0.0%, 2.4 ± 0.1%, and 66.1 ± 2.2%, respectively. Tocopherol contents were 84, 19, 85, and 23 μg/g oil for α-, β-, γ-, and δ-tocopherol. Melting range of SL was narrower than that of EHO. Oxidative stability index (OSI) value of SL (0.80 h) was similar to that of EHO (0.88 h). This SL can be used in infant formulas to provide the benefits of ARA and DHA.  相似文献   
108.
The aim of this study was to determine the fattening performance and the slaughter and carcass characteristics of Akkeçi (Saanen × Kilis (B1) crossbred) male kids raised in individual crates (IC) or in group pen housing (GP). In both GP and IC groups, total 13 heads of male kids, whose initial body weights were 21.43 ± 1.03 kg and 20.61 ± 0.98 kg, respectively, evaluated for their fattening performances. After 56 days of the fattening period, the final body weights and average daily weight gains of the GP and IC kids were recorded as 30.84 ± 0.82 kg and 25.84 ± 0.76 kg; 182.42 ± 14.77 g and 92.09 ± 13.76 g, respectively (P < 0.001). Adrenal gland weights of the GP and IC groups were similar as 1.66 ± 0.25 g and 1.77 ± 0.22 g, respectively. Although, the carcass conformation of kids was similar between groups, there were significant differences between GP and IC groups for some slaughter and carcass characteristics. In general, although housing kids reared in individual crates provides opportunity to individually feed and monitor a kid, the results obtained from the individual crates in the present study were not satisfactorily from the ethological and production points of view.  相似文献   
109.
With 8 figures SUMMARY: This study aimed at revealing the origin, course and distribution of the hypoglossal nerve in 20 adult male New Zealand rabbits. In all the animals dissected, the hypoglossal nerve arose from the ventrolateral side of the medulla oblongata with two main roots and gave off a descending branch to the ansa cervicalis before reaching the division of the common carotid artery. This branch was not seen on the right side of only one case. At the lateral aspect of the hyoglossus muscle, the nerve then divided into the lateral and medial main branches, sent branches to the styloglossus, hyoglossus, genioglossus and geniohyoideus muscles and terminated in the intrinsic tongue muscles. A communicating branch was observed between the hypoglossal and accessory nerves in the right side of one animal and between the hypoglossal nerve and the ganglion nodosum in the right retropharyngeal area of another animal. An additional branch was observed innervating the stylohyoideus muscle in one animal only. A lateral lingual-hypoglossal communication was also seen between the lateral branch of the hypoglossal nerve and terminal branches of the lingual nerve.  相似文献   
110.
The effects of vitamin E and vitamin E-selenium combination on seminal plasma arginase activity and nitric oxide level and some spermatological properties in rams were investigated in this study. For control group, animals were injected intramuscularly with physiological saline. For vitamin E group, rams were injected intramuscularly with 300 mg/ram vitamin E. For vitamin E + selenium group, animals were injected intramuscularly with 5 ml/ram vitamin E + selenium. The semen was collected by artificial vagina at 1st, 4th, 24th, 48th and 72nd hr after administration in each group. Significant decreases in seminal plasma arginase activity (at 1st, 24th and 48th hr), nitric oxide level (at 72nd hr) and abnormal sperm rate (at 1st, 24th and 72nd hr), and significant increases in semen volume (at 24th hr), semen mass activity (at 24th and 48th hr), sperm motility (at 24th, 48th and 72nd hr) and concentration (at 1st hr) were observed in vitamin E group compared with control group. Similarly, significant increase in semen volume (at 1st, 24th and 48th hr), mass activity, (at 48th hr), motility (at 48th and 72nd hr) and concentration (at 4th, 24th and 48th hr), and significant decrements in abnormal sperm rate (at 1st, 24th, 48th and 72nd hr), seminal plasma nitric oxide level (at 1st, 4th, 24th and 48th hr) and semen pH (at 24th and 48th hr) were detected in vitamin E + selenium group in comparison to the control group. As a result, it is suggested that vitamin E and/or vitamin E + selenium applications may improve reproductive performance.  相似文献   
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