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91.
The purpose of this study was to elucidate the effects of medium-chain fatty acids (MCFAs) on plasma ghrelin concentration in lactating dairy cows. Five early-lactating Holstein cows were randomly assigned to 2 dietary treatments in a crossover design with 2-wk periods. Treatments consisted of diets supplemented or not (control) with calcium salts of MCFAs (MCFA-Ca; 1.5% dry matter). Plasma hormone and metabolite concentrations in blood samples taken from the jugular vein were measured on the morning of feeding on day 14 of each period. Dry matter intake, milk protein, and lactose content of cows fed the MCFA-Ca diet were decreased compared with controls, but with no change in milk yield. Plasma ghrelin concentrations were higher in cows fed the MCFA-Ca diet; however, no significant effect was found on glucagon-like peptide-1 concentrations in plasma. Plasma insulin concentrations decreased, but plasma glucagon concentrations remained unchanged in cows fed the MCFA-Ca diet. The concentrations of nonesterified FAs, total cholesterol, and β-hydroxybutyrate in plasma increased in these cows. In conclusion, dietary MCFAs increase the plasma ghrelin concentrations in lactating dairy cows.  相似文献   
92.
93.
Several single nucleotide polymorphisms (SNP) in the bovine CXCR1 gene have been implicated in resistance to mastitis and milk somatic cell counts in several sample populations of Holstein dairy cows. As such, a more thorough understanding of SNP present in and near the bovine CXCR1 gene is needed. This study identified 36 SNP in the coding region and surrounding sequences of CXCR1 in 88 Holstein dairy cows. Four SNP induced amino acid changes and 1 SNP an early stop codon. Two amino acid changes occur in the third intracellular loop and C-terminus in locations tied to intracellular signaling. The 36 SNP could be subdivided into 4 separate linkage groups. Using representative or 'tag' SNP from each linkage group, haplotypes or the combination of SNP found on a single allele were generated to increase the specificity of an animal's genetic background. Four haplotypes were identified that represented 99% of the sample population. The haplotypes generated using tag SNP agreed with haplotypes generated from SNP causing amino acid changes. In conclusion, the CXCR1 gene is highly polymorphic and has potential implications towards genetic selection and understanding host factors that increase the risk of infection.  相似文献   
94.
We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.  相似文献   
95.
Climate change resulting from increased atmospheric carbon dioxide (CO2) and shortages of fossil fuels such as petroleum are major problems worldwide. Under these conditions, demand for woody biomass resources is increasing. We investigated the feasibility of using fast-growing Eucalyptus grandis for material production. Samples of E. grandis were collected from four plantations in different latitude divisions, including tropical and subtropical Brazil and subtropical Argentina. Various xylem qualities were measured and related to the lateral growth rate. Lateral growth rate did not significantly affect the longitudinal released strain of the surface growth stresses or the xylem density at any of the sampling sites. Higher lateral growth rate, higher values of xylem density, and lower absolute values of the released strain were observed in plantations closer to the equator. Higher growth rates in tropical climate promote longer fiber length. In subtropical plantations, smaller diameter trees will produce tension wood with smaller microfibril angles. Planting E. grandis closer to the equator thus produces higher quality wood than in plantations at lower latitudes.  相似文献   
96.
The objective of this study is to identify the properties and responsible compounds for the aromatic roast odor (retort beef aroma) that commonly occurs in canned beef products and could contribute to their palatability. The optimal temperature for generating retort beef aroma was 121°C. An untrained panel evaluated both uncured corned beef and canned yamato‐ni beef and found that they had an aroma that was significantly (< 0.01) similar to the odor of 121°C‐heated beef than 100°C‐heated beef. The panel also noted that the aroma of 121°C‐heated beef tended to be (< 0.1) preferable than that of 100°C‐heated beef. These results suggest that retort beef aroma is one constituent of palatability in canned beef. GC‐MS (gas chromatography‐mass spectrometry) analysis of the volatile fraction obtained from 100°C‐ and 121°C‐heated beef showed that the amounts of pyrazine, 2‐methylpyrazine and diacetyl were higher in the 121°C‐heated beef than in the 100°C‐heated beef. GC‐sniffing revealed that the odor quality of pyrazines was similar to that of retort beef aroma. Therefore, pyrazines were suggested to be a candidate responsible for the retort beef aroma. Analysis of commercial uncured corned beef and cured corned beef confirmed the presence of pyrazine, 2‐methylpyrazine and 2,6‐dimethylpyrazine.  相似文献   
97.
Indigestible oligosaccharides have been shown to normalize blood glucose and insulin concentration thereby promoting good health and preventing diseases, such as diabetes. Transglucosidase (TG, α-glucosidase, enzyme code (EC) 3.2.1.20) is an enzyme capable of converting starch to oligosaccharides, such as iso-malto-oligosaccharides from maltose, via the action of amylase. The aim of this study was to evaluate whether oral administration of TG with maltose or dextrin is capable of reducing post-prandial serum glucose concentration in experimentally streptozotocin (STZ)-induced diabetic dogs fed on a high-fiber diet. Five healthy and five STZ-induced diabetic dogs were employed in this study. TG supplementation with dextrin or maltose had no detrimental effect in healthy dogs. In fact, TG and dextrin exhibited a flatlined serum glucose pattern, while reducing mean post-prandial serum insulin and glucose concentration as compared to control diet alone. When TG supplementation was tested in STZ-induced diabetic dogs under the context of a high fiber diet, a 13.8% and 23.9% reduction in mean glucose concentration for TG with maltose and dextrin, respectively was observed. Moreover, TG with dextrin resulted in a 13% lower mean post-prandial glucose concentration than TG with maltose, suggesting that dextrin may be a more efficient substrate than maltose when used at the same concentration (1 g/kg). Our results indicate that TG supplementation with diet can lead to lower postprandial glucose levels versus diet alone. However, the efficacy of TG supplementation may depend on the type of diet it is supplemented with. As such, TG administration may be useful for preventing the progression of diabetes mellitus and in its management in dogs.  相似文献   
98.
The aim of this study was to examine the possible differences of oestrous intensity between natural oestrus and induced oestrus using the walking activity measuring device. Walking activity was used as an evaluation index of oestrous intensity. A total of 27 Japanese Black cows, more than 40 days after calving and clinically normal, were randomly assigned to three groups. Walking activity was recorded using a commercially available computerized pedometer system. The treatment groups consisted of an Ovsynch (n = 8) and a controlled internal drugs releasing device (CIDR) + Ovsynch (n = 9) group. The control group (n = 10) received no treatment. Walking activity was examined in all groups. Timed artificial insemination (timed AI) was performed at 16 hours after the onset of oestrus in the control group and at 24 h after second administration of GnRH in the treatment groups. Duration of oestrus had a tendency to be shorter in both the Ovsynch and the CIDR + Ovsynch groups when compared with the control group. The time required from the onset of oestrus to the time showing the highest number of steps of walking (the time to peak) showed a tendency to be shorter in CIDR + Ovsynch group. The number of steps of walking at peak and overall walking activities were significantly lower in both treatment groups than in the control group. Both activity and super-activity periods of time in the treatment groups were shorter than the control group. No difference was observed in the conception rate between the control (50.0%; 10/20), Ovsynch (50.0%; 4/8) and CIDR + Ovsynch groups (66.7%; 6/9). This study demonstrates that the oestrous intensity of cows in oestrus was different between natural oestrus and induced oestrus and also between the methods of the synchronization, but no difference was observed in the conception rate among the three groups.  相似文献   
99.
The objective of this study was to propose a model for explaining rice responses to a wide range of N application rates in various growth attributes associated with the occurrence of chalky grains. We improved the sub-model for N uptake process of a previous rice model which was originally developed for explaining genotypic and environmental variations in the whole growth processes, considering the difference in the rate of N loss from the plant-soil system between indigenously supplied soil mineral N and fertilizer N. A total of 80 growth datasets of cultivar ‘Koshihikari’ grown at Shiga prefecture, Japan, in 2010 was utilized for the calibration and validation of the model. The rice growth model well explained the above-ground biomass growth (RMSD = 78.7 g m?2) and rough dry grain yield (RMSD = 83.2 g m?2) for the validation data-set, simultaneously. The simulated carbohydrate content available per single spikelet was negatively correlated with the observed percentage of the milky-white grain which includes white-cored grain (r = ?.77, p < .001) for all the data-sets of calibration and validation. On the other hand, the observed percentage of the sum of white-back and white-base grains was closely correlated with the simulated plant N content available per single spikelet (r = ?.59, p < .001). It was suggested that the present rice growth model would rationally explain the effects of N application on the occurrence of the chalky grains through the dynamic change of the carbohydrate content and plant N content available per single spikelet.  相似文献   
100.
Cytoplasmic male sterility (CMS) is an indispensable trait for F1 hybrid seed production in bunching onion (Allium fistulosum L.). Expansion of the cytoplasmic diversity of F1 hybrid cultivars by introduction of various CMS resources has great potential to eliminate vulnerability to cytoplasm type-specific diseases. This study aimed to evaluate appearance frequency of male sterile plants in several bunching onion accessions and to identify CMS resources. In eight (‘Nogiwa Aigara’, ‘Bansei Hanegi’, ‘Amarume’, ‘Kimnung’, ‘Zhangqiu’, ‘INT/CHN/1990/GOTOU’, ‘Natsunegi’ and ‘Guangzhou’) of 135 accessions collected from Japan, China, Mongolia, Korea and Taiwan, male sterile plants appeared with varied frequencies from 1.7% (‘Nogiwa Aigara’ and ‘Bansei Hanegi’) to 24.5% (‘Zhangqiu’). The inheritance mode of Zhangqiu- and Guangzhou-derived male sterility was confirmed to be CMS by sib-crossings and interbreed crossings. Microscopic examination of microsporogenesis in the CMS plants revealed that microspore protoplasm rapidly degenerated without mitotic division after the release of microspores from tetrads. The CMS germplasm described here would be useful for the development of “A” lines to be used in F1 hybrid seed production of bunching onion. Male fertility in ‘Nogiwa Aigara’, ‘Bansei Hanegi’, ‘Kimnung’, ‘INT/CHN/1990/GOTOU’ and ‘Natsunegi’ was verified to be controlled by a single fertility restoration locus.  相似文献   
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