Dietary supplementation with Mannanoligosaccharides (MOS) from Bio‐Mos enhances growth parameters and digestive capacity of gilthead sea bream (Sparus aurata)

Dietary mannanoligosaccharide (MOS) from commercial product, Bio‐Mos supplementation, has been examined for its effects on weight gain and feed conversion of domestic mammals and birds, but very few studies have evaluated the responses of aquacultural species to MOS. A feeding and digestibility trial was performed to asses the potential beneficial effect of two levels of Bio‐Mos on growth, feed utilization, survival rate and nutrients’ digestion of gilthead sea bream (Sparus aurata) with an initial average weight of 170 g. Bio‐Mos was added at 2 or 4 g kg^?1 to a fish meal–based control diet, and each diet was fed to triplicate groups of 1‐year‐old gilthead sea bream. After 12 weeks, there were no differences in survival rate among fish fed experimental diets (P > 0.05). It was observed that a significant improvability existed for both growth and feed utilization in fish fed diets supplemented with Bio‐Mos (P < 0.05). Body proximate composition remained unaffected by Bio‐Mos supplementation in fish fed experimental diets (P > 0.05). Apparent digestibility values for protein, carbohydrate and energy were appreciably affected by the inclusion of two different levels of Bio‐Mos, only lipid digestibility was the exception. In conclusion, the results of this trial indicate that 2 g kg^?1 dietary supplementation with BIO‐MOS seem to be most positive for gilthead sea bream production.     

The development of Erysiphe cruciferarum on field-grown Brussels sprouts and associated changes in soluble amino-acids in foliage leaves

Percentage leaf area diseased was assessed in two plantings of Brussels sprouts cv. Goldmine from June to October 1981. on marked leaves, enabling disease progress curves to be calculated for the crops and for individual leaves. Mean amounts of disease, corrected for loss of infections through leaf abscission, were compared with meteorological parameters by multiple regression analysis (MRA). Disease increase, especially on the upper leaf surface, was associated negatively with rainfall and positively with relative humidity. Temperature also contributed significantly to the regressions but its effects were not consistent. Disease, uncorrected for removals, was compared by MRA with changes in soluble amino-N compounds in leaves, especially amino-acids. The amounts of proline and alanine were positively associated with infection and those of glutamic acid, leucine and amides were negatively associated with infection.     

关于旅大地区小麦秆锈菌和叶锈菌夏孢子世代的越冬问题

 关于小麦秆锈和叶锈的越冬问题,国外业巳有许多报告^{[10,13,14,15,16,17,18]}。国内在小麦锈菌越冬方面也有一些报导。     

MAGNETIC RESONANCE IMAGING FEATURES OF OBLIQUE AND STRAIGHT DISTAL SESAMOIDEAN DESMITIS IN 27 HORSES

Injury to the oblique and straight distal sesamoidean ligaments is becoming recognized as a more common cause of lameness in horses than was previously thought. The purpose of this study was to review the magnetic resonance (MR) imaging findings of 27 horses affected with desmitis of the oblique and/or straight distal sesamoidean ligament and determine long-term prognosis for horses with this diagnosis. Imaging was performed with horses in right lateral recumbency in a high-field 1 T magnet. All horses had lameness localized to the digit or metacarpophalangeal/metatarsophalangeal joint region with diagnostic local anesthetic blocks. Ten horses had forelimb lameness and 17 horses had hind limb lameness. MR imaging revealed abnormalities in the oblique distal sesamoidean ligaments in 18 horses, in the straight distal sesamoidean ligament in three horses, and in both the oblique and straight distal sesamoidean ligament in six horses. Treatment consisted of a 6-month rest and rehabilitation program in all horses. The digital flexor tendon sheath was injected with methylprednisolone acetate and hyaluronic acid in 22 horses to decrease inflammation in the injured ligaments before starting the rest and rehabilitation program. Two horses had ligament splitting performed, one in the oblique distal sesamoidean ligament and one in the straight distal sesamoidean ligament. MR imaging is an effective method for diagnosing injury to the oblique and straight distal sesamoidean ligaments in horses. Treatment, primarily a 6-month rest and rehabilitation program, allowed 76% of the horses to successfully resume performance.     

红壤微生物学特性(一)浙江省衢县低丘红壤的微生物学分析

浙江省的低丘红壤主要有两种类型,一种是以第四纪初期洪积体-红土层为母质,经长期的自然生物气候条件作用发育而成的红-黄色土壤,农民称为“黄筋泥”。黄筋泥土层深厚,质地一般属粉砂质粘土,呈强酸性反应。另一种是以衢江红砂岩的风化体为母质发育而成的土壤,称为红砂土。第三纪衢江红砂岩地层处在第四纪红土层之下,因此只有在红土层受到侵触,红砂岩暴露出来的地方,红砂土才能形成。在低丘红壤区里,黄筋泥和红砂土交错地分布着,构成复区。     

Factors affecting the production of apothecia and longevity of sclerotia of Sclerotinia sclerotiorum

Sclerotia of Sclerotinia sclerotiorum produced naturally on winter oilseed rape and by an isolate from this host on sterile wheat grain were placed in two different soil types in pots, either on the soil surface or 1. 2, 3, 4 or 6 cm deep. Nitrogen (as TN 34, Thames Nitrogen Co.) was applied to one set of pots in autumn 1982 and spring 1983. Production of apothecia was recorded in this set in 1983 only. In pots without added N apothecia were counted in 1983 and 1984 and sclerotia were recovered from these pots at the end of the experiment.
Overall, production of apothecia was not affected by soil type. More apothecia formed from cultured sclerotia and they appeared earlier than from natural sclerotia. More apothecia were produced from sclerotia placed at 0–2 cm than from those buried deeper. Fewer apothecia were produced in pots with added N and their production was delayed. Fewer sclerotia were recovered from the upper layers of soil with a higher clay content, and when sclerotia were obtained from oilseed rape rather than from cultures.     

THE CORPORATE ROLE OF LARGE METROPOLITAN AREAS IN THE UNITED STATES

This study has three purposes. The first is to determine, for the 30 largest U.S. metropolitan areas in 1980. the relationship among population size, the number of major corporations headquartered in these centers, and the number of subsidiaries located there. The expectation is that there will be positive relationships in all cases. Second, this study, based on variations in the relationships examined above, sets forth a corporate classification of the 30 metropolitan areas and identifies common characteristics and locations among six categories of centers. Finally, using the six-fold classification of centers, metropolitan employment growth between 1980 and 1986 is analyzed, especially job growth in services and in finance, insurance, and real estate (FIRE). The six-fold classification proves useful in understanding employment growth in these 30 centers during the 1980s and, with modifications, perhaps beyond.     

土壤电化学特牲的研究——Ⅰ.水稻土的电导与其肥力的关系

1.设计了一个在田间直接测定水稻土的电导的电导池,用以鉴别水稻土的肥力状况。根据条件试验,在水稻生长期间通常变动的水分含量范围以内,水分含量的差别可以不予考虑。土壤胶体本身的电荷在电导上的贡献也很小,所以一般也不必考虑。土壤含砂粒较多时,应该加以适当的改正值。2.根据大量的田间测定结果,在酸性的水稻土中,电导与肥力水平成明显相关。施肥的数量和种类对土壤电导发生显著的影响。由于水稻对养分的吸收,所以根际土壤的电导较根外为低,并且随着水稻的生长,而使土壤电导降低。3.酸性水稻土的干土渍水后电导的增加数值与土壤的肥力水平成正相关。这种电导的增加,基本上是由于有机质的分解所致。4.根据与化学分析的对照结果,土壤溶液的电导与阳离子的浓度成明显相关。在引起酸性水稻土电导的阳离子中,钙镁占90—95%,钾占2—8%,铁和铵的数量都在1%以下。5.作者根据研究结果,认为电导可以作为鉴别酸性水稻土的肥力水平的一个简便的综合性参考指标。     

不同有机肥对土壤中的氮素矿化及对化肥氮固持的影响

采用^15N示踪法研究不同有机肥品种在土壤中的氮素矿化释放规律及对化肥氮固定的影响。结果表明,培养90d后,鸡粪、豆粕米糠混合肥氮素矿化量分别达到了95．6和185．4mg／kg,而牛粪和污泥堆肥分别为-28．1和-10．9mg／kg。4种有机肥在化肥施入土壤后,对化肥氮在土壤中的保留进行了观察,鸡粪和豆粕米糠混合肥对化肥氮的固持率明显高于牛粪和污泥堆肥。