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排序方式: 共有607条查询结果,搜索用时 31 毫秒
31.
Kazuhiro WATANABE Kotaro HAYASHI Saku KIJIMA Chie NONAKA Kazuaki YAMAZOE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1323-1325
In this study, scaling, polishing and daily tooth brushing were performed in 20 beagle
dogs, and the number of oral bacteria was determined using a bacterial counter. The dogs
were randomized into the scaling (S), scaling + polishing (SP), scaling + tooth daily
brushing (SB) and scaling + polishing + tooth daily brushing (SPB) groups. Samples were
collected from the buccal surface of the maxillary fourth premolars of the dogs
immediately after scaling and every week thereafter from weeks 1 to 8. Throughout the
study, the number of bacteria was significantly lower in the SB and SPB groups compared
with the S group. The findings suggest that daily tooth brushing inhibited oral bacterial
growth in the dogs. 相似文献
32.
33.
Nishimura M Ishiyama K Watanabe A Kawano S Miyase T Sano M 《Journal of agricultural and food chemistry》2007,55(18):7252-7257
A quantitative method for four theaflavins and two methylated theaflavin derivatives in black tea leaves was developed by solid-phase extraction and a high-performance liquid chromatographic method with photodiode array detection. The theaflavins in black tea leaves were extracted three times with 40 vol 50% aqueous ethanol (mg dry tea powder/mL) containing 2% ascorbic acid. The ethanol extracts were diluted 4-fold with distilled water. All diluted extracts were directly applied to the solid-phase C18 cartridge column without concentration. The fraction of theaflavins was obtained by 40% ethanol extraction after rinsing with water followed with 15% ethanol extraction. An aliquot of theaflavins after concentration was injected onto an ODS C18 reversed-phase column, and four theaflavins and two methylated theaflavins were sufficiently separated by a linear gradient system using distilled water and acetonitrile with 0.5% acetic acid. This analytical method is sensitive for the determination of a small amount of methylated theaflavins, since various interfering substances produced during the fermentation process were eliminated in advance by solid-phase extraction. Using this analytical method, we also demonstrated that methylated theaflavins were easily produced during the manufacture of black tea. 相似文献
34.
Strategies for further development of aquatic feeds 总被引:4,自引:1,他引:4
ABSTRACT: To date, aquatic feeds have depended heavily on fishmeal and fish oil as their source of protein and lipid. However, the feed industry is encountering shortfalls in the availability of these ingredients because of a decline in the number of fish captured in the wild and the increased human demand for some of the species currently being used for fishmeal and oil production. Therefore, efforts are now being directed in different parts of the world to finding alternative quality ingredients, which ideally are less expensive and readily available for use in practical diets. The data accrued have shown that a large proportion of both fishmeal and fish oil can be replaced by other protein and lipid sources. However, it is emphasized that an optimal essential amino acid balance be maintained and that the n-3 highly unsaturated fatty acid requirement be satisfied when combining economical protein and lipid ingredients. Newly developed feeds should aim at being nutrient-dense in order to reduce the output of solid, P and N waste. This can be done through improving nutrient availability, optimizing the digestible protein to energy balance of the diet, and replacing dietary fishmeal with alternate ingredients. These diets should also be effective for maintaining good health and improving disease resistance in fish through enhancement of immune responses. A wholesome approach to culturing fish would be to use appropriate feeding standards that are aimed not only at improving economic returns but also at developing a lasting cohabitation of sustainable aquaculture and a cleaner environment. Furthermore, in the 2lst century aquaculture would still retain its place as a prominent source of food protein, signifying that fish feed research remains a forceful area in discovering better feeds for the industry. 相似文献
35.
36.
Noritaka ADACHI Daisuke YAMAGUCHI Akiyuki WATANABE Narumi MIURA Seiji SUNAGA Hitoshi OISHI Michiko HASHIMOTO Takatsugu OISHI Masaki IWAMOTO Hirofumi HANADA Masanori KUBO Akira ONISHI 《The Journal of reproduction and development》2014,60(2):100-105
The objective of this study was to examine the health and meat production of cloned sows
and their progenies in order to demonstrate the application of somatic cell cloning to the
pig industry. This study compared the growth, reproductive performance, carcass
characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies.
We measured their body weight, growth rate and feed conversion and performed a
pathological analysis of their anatomy to detect abnormalities. Three of the five cloned
pigs were used for a growth test. Cloned pigs grew normally and had characteristics
similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a
Landrace boar and used for a progeny test. F1 progenies had characteristics similar to
those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White
boar and used for the progeny test. F2 progenies grew normally. There were no biological
differences in growth, carcass characteristics and amino acid composition among cloned
sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies
showed normal reproductive performance. No specific abnormalities were observed by
pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs
had a normal karyotype. These results demonstrate that cloned female pigs and their
progenies have similar growth, reproductive performance and carcass quality
characteristics and that somatic cell cloning could be a useful technique for conserving
superior pig breeds in conventional meat production. 相似文献
37.
Fuminori Tarui Yutaka Haga Kengo Ohta Yasuhiro Shima Toshio Takeuchi 《Fisheries Science》2006,72(2):256-262
ABSTRACT: The effect of Artemia nauplii enriched with different level of vitamin A (VA) palmitate (1 µg = 1 IU) on the occurrence of hypermelanosis on the blind side of Japanese flounder Paralichthys olivaceus was determined. Artemia were enriched with 0, 1, 2, 5 or 10 mg VA palmitate/L (control group, and 1-, 2-, 5-, and 10-mg groups). The enriched Artemia were fed to the larvae from 27 to 31 days post hatching (dph) corresponding to the F–G stage. VA palmitate, retinol and retinoic acid (RA) contents of Artemia were correlatively elevated with increasing VA palmitate in the culture medium. RA was detected in Artemia enriched with 5 mg and 10 mg, and a significantly high frequency of hypermelanosis on the blind side was observed in these groups at 65 dph ( P < 0.05). These results suggest that RA synthesized from VA palmitate in Artemia could induce hypermelanosis on blind side of flounder when Artemia are enriched with more than 5 mg VA palmitate/L. 相似文献
38.
39.
Toshio Akiyama Takeshi Murai Yasuhiro Hirasawa Takeshi Nose 《Aquaculture (Amsterdam, Netherlands)》1984,37(3):217-222
In a 6-week feeding experiment, chum salmon, Oncorhynchus keta, swim-up fry, were fed fish meal diets supplemented with silkworm pupae powder (5%), dried beef liver (5%), krill meal (5%) or earthworm powder (5%) at the expense of fish meal, or substituting glucose (13%) for dextrin. Fish fed the diet with earthworm powder showed the best growth performance (675% weight gain in 6 weeks) and feed efficiency (117%). The growth rate and feed efficiency of the krill meal group were also significantly better than those of the control group (without supplement or substitution). Substitution of glucose and supplementation of silkworm pupae or beef liver failed to improve the growth rate, but significantly improved feed efficiency. Food consumption of fish fed the diet supplemented with earthworms was lowest, and none of the dietary treatments appreciably increased food intake of the fish over that of the control group. The dietary group receiving earthworm powder also showed significantly higher body fat content than the remaining dietary groups. No significant differences were noted in body protein and ash contents among all dietary treatments. 相似文献
40.
Two 21 day experiments were conducted to determine whether microparticulate diets could be used to substitute for diatoms for raising (Experiment 1) as well as settling and on‐growing (Experiment 2) Haliotis diversicolor supertexta postlarvae. The experiments were conducted in 10 L flow‐through tanks and each diet had three replicate tanks. In experiment 1, three experimental microparticulate diets supplied by a commercial feed company, labelled SF‐15, SF‐15 (T) and JFY‐13–1, were used, and in experiment 2, SF‐15 and SF‐15 (T). Artificial diets were compared to diatoms in terms of supporting growth and survival. The survival rate for experiment 1 was lowest for JFY‐13–1 (0%) and highest for diatoms (12.9±0.8%). The final size of postlarvae fed SF‐15 and SF‐15 (T) was significantly greater than that of postlarvae fed diatoms, 973±193 μm and 996±220 μm compared to 786±141 μm. In experiment 2, a total number of 501 larvae settled onto plates covered with SF‐15, 254 on SF‐15 (T) and 1085 on diatoms. The highest survival rate was 33.1±6.9% for SF‐15 and the lowest was 17.3±5.0% for diatoms. However, the final length of postlarvae fed diatoms was significantly greater than SF‐15 and SF‐15 (T); 1018±379 μm compared to 728±89 μm and 717±90 μm. The artificial micro diets used in this study were comparable to diatoms in terms of grow and survival of postlarval H. diversicolor supertexta. 相似文献