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1.
This study aimed to determine the effects of feeding an increased volume of high‐fat milk during the early post‐natal life on metabolite concentrations in the blood, the expression of key genes regulating intermediary metabolism in the skeletal muscles, and the rate of growth of Japanese Black cattle. All calves were fed a high‐fat milk replacer (crude protein, 26%; crude fat, 25.5%; total dissolved nitrogen, 116%). Control calves (n = 4) were nursed with 500 g milk replacer until 3 months of age, whereas calves in the experimental group (n = 4) were nursed with 1800 g milk replacer until 3 months, and then the volume was gradually reduced until 5 months. Body weight was significantly higher in the experimental group than in the control group at 7 months. Plasma glucose concentrations were significantly lower in the experimental group. Expression of glucose‐transporter‐4 messenger RNA (mRNA) was lower, whereas that of glucose transporter 1, cluster of differentiation 36, and carnitine palmitoyltransferase‐1b mRNA was significantly higher in the Longissimus thoracis of the experimental group. Nutritional status during early post‐natal life appears to strongly influence the growth rate and glucose and lipid metabolism in Japanese Black cattle.  相似文献   
2.
In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed.  相似文献   
3.
Japanese isolates of Verticillium dahliae, a causal agent of wilt disease in many plants, are classifiable into pathotypes based on their pathogenicity. Because these pathotypes are morphologically indistinguishable, establishing a rapid identification method is very important for the control of this pathogen in Japan. For cloning DNA fragments that are useful for identification and specific detection of V. dahliae pathotypes, we performed random amplified polymorphic DNA (RAPD) analyses using various isolates. One polymerase chain reaction (PCR) product, E10-U48, was specific to isolates pathogenic to sweet pepper. The other product, B68-TV, was specific to race 1 of isolates pathogenic to tomato. The specificity of these sequences was confirmed by genomic Southern hybridization. Further analyses revealed that the region peripheral to B68-TV obtained from the genomic DNA library includes the sequence specific to all isolates pathogenic to tomato (races 1 and 2). Moreover, sequence tagged site (STS) primers designed from B68-TV and its peripheral region showed race-specific and pathotype-specific amplification in a PCR assay. The probes and primers obtained in this study are likely to be useful tools for the identification and specific detection of pathotypes and races of V. dahliae. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB095266.  相似文献   
4.
ABSTRACT:   To elucidate the utilization of the major yolk nutrient stocks in eggs and larvae of walleye pollock Theragra chalcogramma , the contents of free amino acids (FAA), the major yolk protein (180 kDa lipovitellin originated from vitellogenin B in ovulated eggs: oLv B), and lipids were measured. Most eggs hatched 18 days after fertilization at 5°C, and all larvae absorbed almost all their yolk mass by 28 days. The total FAA content showed no change during the first 6 days, and then decreased to 28% of the initial level by 18 days. The oLv B contents, measured by an enzyme-linked immunosorbent assay using a specific antiserum against oLv B, gradually decreased from 6 to 18 days, followed by a rapid decline. The content of phospholipids (PL) and triacylglycerols (TG) showed no marked change until hatching, and then decreased until disappearance of yolk sac. From these results, it is proposed that there are two main periods for nutrient utilization in embryos and larvae of walleye pollock. In the first period, FAA was mainly utilized until 18 days after fertilization. Active utilization of oLv B and lipids (PL and TG) instead of FAA occurred during the second period from 18 to 28 days.  相似文献   
5.
Three distinct forms of vitellogenin (Vg), 600 kDa VgA and VgB and 400 kDa Vg, were discovered biochemically in estrogen treated female plasma. By sequencing of the three Vg cDNAs, the VgA and VgB were recognized as complete Vgs having all yolk protein (YP) domains, and the 400 kDa Vg was thought to be phosvitinless (Pvl) Vg lacking phosvitin (Pv) domain.  相似文献   
6.
The understanding of animal products and dairy farming is important for the promotion of dairy farming. Thus, to examine the effects of farm experience on the understanding of animal products and the management of dairy farming, the interaction between students and dairy cows was investigated in groups of first‐year veterinary nursing students in 2011 and 2012 (n = 201). These students included 181 women and 20 men. Nine items about dairy cows were presented in a questionnaire. The survey was performed before and after praxis on the educational farm attached to the authors' university. After praxis on the farm, increases occurred in the number of positive responses to the items involving the price of milk, dairy farming and the taste of milk. For these items, a significant difference (P < 0.05) was found between the scores obtained before and after training. The results of the study suggested that farm experience is useful for improving the understanding of animal products and dairy farming.  相似文献   
7.
A full-length cDNA encoding a vitellogenin (Vg) receptor (VgR) was isolated and sequenced from a white perch, Morone americana, ovarian cDNA library. The perch expresses a single VgR that is structurally classified as an LR8 type (without an 0-linked sugar domain) and appears to be the only species observed to possess no splice variant of the receptor. We proposed a hypothetical model for ovarian lipid transfer in Morone species, one in which the `single VgR' transports Vg and other lipoproteins via a selective endocytotic pathway based on ligand affinity, in conjunction with a lipase-mediated pathway of fatty acid transport.  相似文献   
8.
Summary Overcoming self-incompatibility by application of three kinds of plant hormones, sucrose, 3 kinds of amino acids and 2 kinds of vitamines was tested in cvs. Honbashi-taibyo Minowase (H-Mino) and Minowase (Mino) of Raphanus sativus. Effects differed between the cultivars. In H-Mino, BA (100 mg/l) and glutamic acid, folic acid and nicotinic acid (500 mg/l) resulted in higher fruit set and higher number of seeds per pollinated flower. In Mino, BA and NAA (100 mg/l) and glutamic acid and glycine (500 mg/l) induced a high number of seeds per pollinated flower. These chemicals, however, induced parthenocarpic fruit set, especially GA3. From the observation of pollen on stigmas washed with glutamic acid, it appeared that the pollen-tube penetrated into a papilla cell after 1 hour and openings of papillae and detached pollen grains and tubes were found after 2 hours as the result of successful pollentube penetration of papillae. Pollen was heated at 50°C for 30, 45 or 60 minutes, at 60°C for 15, 30 or 45 minutes and at 70°C for 10, 20 or 30 minutes prior to self-pollination. In H-Mino, 60 and 70°C were effective, and expecially 60°C for 15 or 30 minutes resulted a higher percentage fruit set and more seeds per fruit. In Mino, although 50–70°C were effective, the mean number of seeds per pollinated flower was lower than in H-Mino.  相似文献   
9.
Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a multiple-planet system with microlensing. We identify two planets with masses of approximately 0.71 and approximately 0.27 times the mass of Jupiter and orbital separations of approximately 2.3 and approximately 4.6 astronomical units orbiting a primary star of mass approximately 0.50 solar mass at a distance of approximately 1.5 kiloparsecs. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only six confirmed microlensing planet detections suggests that solar system analogs may be common.  相似文献   
10.
Shorter-wavelength surface-emitting laser sources are important for a variety of fields, including photonics, information processing, and biology. We report on the creation of a current-driven blue-violet photonic-crystal surface-emitting laser. We have developed a fabrication method, named "air holes retained over growth," in order to construct a two-dimensional gallium nitride (GaN)/air photonic-crystal structure. The resulting periodic structure has a photonic-crystal band-edge effect sufficient for the successful operation of a current-injection surface-emitting laser. This represents an important step in the development of laser sources that could be focused to a size much less than the wavelength and be integrated two-dimensionally at such short wavelengths.  相似文献   
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