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11.
In pig production, dietary additive antibiotics are usually used for growth stimulation and disease prevention, although there is public concern about the increased incidence of resistant antibiotics and food safety. It is possible that such antibiotics might be replaced by naturally derived products such as seaweed and licorice. In this study, we evaluated the effect of dietary addition of seaweed and licorice on enhancing the immune function in swine. The animals of each group (eight animals per group) were sensitized at day 42 and 49, and the immunoglobulin production and the expression of cytokines were detected by the ELISA and real‐time PCR. As the results, saliva IgA production of the seaweed‐treated group increased around five times compared to that of control (day 56). Delayed hypersensitivity reaction and IgG production of the seaweed‐treated group increased around 1.8–2.0 times. In addition, enhanced saliva IgA production was detected at day 50 (around two times) and day 51 (around five times) by the licorice treatment, and lower expression level of tumor necrosis factor‐α messenger RNA at day 51 (around 1/25) was observed in the licorice treatment. We conclude that the replacement of antibiotics by naturally derived dietary additives might be feasible for immune system enhancement.  相似文献   
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The purpose of the present study was to evaluate effects of medium‐chain fatty acid‐cyclodextrin (CD) complexes on ruminal methane and volatile fatty acid production, and protozoal activity in vitro. Medium‐chain fatty acid‐CDs used in this study were caprylic acid (C8)‐αCD or ‐βCD, capric acid (C10)‐αCD or ‐βCD, and lauric acid (C12)‐αCD or ‐βCD. A 60‐mL of diluted rumen fluid was incubated anaerobically at 38°C for 6 h with the addition of the complex (10–40 mg as fatty acid). Each of the fatty acid‐CDs reduced the number of protozoa, with the order C10 > C12 > C8, and βCD complexes were more effective than αCD complexes. Molar proportions of acetic acid remained unchanged with the addition of fatty acid‐CD, while that of propionic acid increased, being significant for C8‐αCD and βCD, and C10‐αCD and βCD (P < 0.05). Hydrogen production decreased by about 70% of control with the addition of 40 mg of C8 and C10‐CD, on the other hand, it tended to increase with the addition of C12‐CD in both αCD and βCD. Methane production decreased by about 20% with the addition of 40 mg of complexes, except for C10‐βCD, which significantly reduced methane production by about 60%. In conclusion, the addition of C8 or C10‐CD to ruminant diets may be effective in reducing methane production.  相似文献   
14.
This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the Antarctic minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Antarctic Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the Antarctic minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea.  相似文献   
15.
Avian botulism is a paralytic disease caused by a toxin produced by Clostridium botulinum type C. Since type C isolates from cases of avian botulism produced a neurotoxin consisting of a mosaic form of parts of type C and D neurotoxins, we examined the antitoxin titers in the convalescent sera of botulism-affected birds which belonged to family Anatidae. ELISA using the C/D mosaic neurotoxin as an antigen revealed that the antibody was detected in the sera at 2 weeks, but not at 5 weeks after the onset, suggesting that the antibody only appeared for a short period in the convalescent phase. However, we failed to detect the antibody titers with anti-chicken IgG instead of anti-duck IgG. We therefore examine the immunological properties of IgG among different families and species. The results revealed that different species of IgG in the same family exhibited strong cross-reactivity. Ducks immunized once with the toxoid together with a commercial oil-adjuvanted vaccine were found to develop sufficient antibody to protect against a challenge with a lethal toxin dose. The ELISA titers did not correspond to the neutralization titers in the sera of immunized ducks at the early stage during immunization. These findings suggest that the neutralizing titer was more useful than the ELISA titer for evaluating the protection against the toxin, but the ELISA technique may be applicable for detecting the occurrence of botulism.  相似文献   
16.
The reaction between Amadori compounds and cysteine was investigated. When 1-deoxymaltulosyl-glycine (glycyl-fructosyl-glucose) was heated at 100 degrees C with cysteine in a neutral aqueous solution, a novel intermediate composed of 1-deoxyosone and cysteine was detected. NMR and mass spectrometry studies revealed the structure of the isolated intermediate to be 7,8a-dihydroxy-4a-methyl-8-(alpha-d-glucopyranosyloxy)hexahydro-5-oxa-4-thia-1-azanaphthalene-2-carboxylic acid. This intermediate easily generated isomaltol and acetylfuran as volatile compounds in 1 mol/L HCl at 100 degrees C.  相似文献   
17.
We used conventional cross-breeding techniques to develop a carnation with low ethylene sensitivity. A time-lapse video recording system for evaluating ethylene sensitivity of flowers, developed in our earlier study, proved useful for this breeding. We selected 10 new ethylene-resistant lines, in addition to the previously selected line 64–54. Lines 902–48a, 234–43S, and 234–36S showed extremely low ethylene sensitivity. The response time to 10 μL L−1 ethylene of these three lines exceeded 50 h in two independent experiments (2004 and 2005), whereas that of three sensitive control cultivars (‘White Sim’, ‘Excerea’, and ‘Scania’) was 6.2–8.0 h. The mean vase life of the ethylene-resistant lines ranged from 7.6 to 12.7 days (1.4–2.3 times that of ‘White Sim’). The application of ethylene to carnation flowers induced autocatalytic ethylene production in both petals and gynoecia of 9 of the 11 ethylene-resistant lines without petal wilting, indicating that the autocatalytic ethylene production was regulated independently of the petal wilting reaction. This result further suggests that these lines have normal ethylene receptors and produce ethylene autocatalytically, but their petal wilting reaction stops at a point beyond the receptor. Two lines (118–64S and 120–69S) showed extremely low ethylene production at flower senescence and very low autocatalytic ethylene production from petals and gynoecia.  相似文献   
18.
Water adsorption capacities were evaluated for moso bamboo samples that were heated at 200°C for various times and conditioned in a closed container at 97% relative humidity at 20°C. Logistic regression analysis was used for curve fitting to the adsorption data and its parameters were analyzed. These parameters were compared with those derived previously from the Dubinin and Radushkevich theory. The properties of the heat-treated samples changed after 5 h of heating. With less than 5 h of heating, hydroxyl groups provided the main adsorption sites but their numbers decreased on heating. After 5 h, gasifi cation of the bamboo increased and capillaries formed. Part of this article was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007  相似文献   
19.
Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high‐producing cows. This study used a simulated milking device to examine the milking performance of the milking system of 73 dairy farms and to analyze the factors affecting claw vacuum. Mean claw vacuum and range of fluctuation of claw vacuum (claw vacuum range) were measured at three different flow rates: 5.7, 7.6 and 8.7 kg/min. At the highest flow rate, only 16 farms (21.9%) met both standards of mean claw vacuum ≥35 kPa and claw vacuum range ≤ 7 kPa, showing that milking systems currently have poor milking performance. The factors affecting mean claw vacuum were claw type, milk‐meter and vacuum shut‐off device; the factor affecting claw vacuum range was claw type. Examination of the milking performance of the milking system using a simulated milking device allows an examination of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum.  相似文献   
20.
【目的】探讨菌株D-5在不同条件下对杜仲种皮固体发酵时羧甲基纤维素(CMC)酶、果胶酶活力及纤维类物质去除率的变化规律,筛选利用微生物固体发酵提取杜仲胶的发酵工艺参数。【方法】以曲霉D-5为发酵菌株,研究发酵基质不同的含水率、初始pH、起爆剂用量、发酵温度对CMC酶、果胶酶活力及纤维类物质去除率的影响。【结果】发酵基质的含水率、初始pH、起爆剂用量、发酵温度对菌株D-5的酶活力及纤维类物质的去除率有显著的影响。菌株D-5发酵的适宜条件为:基质含水率为60%、初始pH6.0、发酵温度30℃、起爆剂用量1.5%,在此条件下发酵6dCMC酶及果胶酶的活力最高,发酵18d纤维类物质去除率可达86.43%。【结论】利用微生物发酵去除纤维类物质是杜仲胶提取的重要途径之一,菌株D-5在杜仲胶提取中有一定的应用价值。  相似文献   
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