全量麦草旋耕还田窗纱旱育苗抛秧稻栽培技术探讨

全量麦草旋耕还田窗纱旱育苗抛秧稻栽培技术是江苏里下河地区农业科学研究所最新研制的窗纱铺垫、旱育秧苗、麦草旋耕还田、带土抛秧的一项轻简稻作技术,2006年试验示范省工节本、增产增效优势明显,具有推广应用价值。其栽培技术为窗纱铺垫旱育壮秧、麦草旋耕还田、带土抛秧;每667m2抛植1.8万~2.0万穴,基本茎蘖苗6万~7万,成穗数22万~23万,成穗率达75%以上,每穗粒数125粒,结实率90%,产量650kg/667m2。施肥策略:施纯氮16~18 kg/667m2,N∶P2O5∶K2O为1∶0.5∶0.8,氮素中基肥∶分蘖肥∶促花肥∶保花肥为40∶30∶15∶15,磷肥全部用作基肥,钾肥基肥和穗肥各占50%。水浆管理措施:泥浆薄水抛秧,湿润促分蘖,适时搁好田,后期间歇灌溉。     

大麦粉替代不同比例玉米对奶牛生产性能的影响

选取泌乳天数、体重、产奶量相近的荷斯坦高产泌乳牛340头,随机分为试验组和对照组两组,每组170头.试验时间共28d,对照组全期饲喂全混合配方日粮(TMR),试验组分四阶段进行,每阶段7d,分别饲喂以10％、20％、30％、40％粉碎大麦粉替代玉米的TMR.结果发现:随着大麦粉替代玉米比例的增加,试验组采食量呈现下降趋...     

利用盐碱地地下水养殖中国对虾试验

1999年在胶州市李格庄镇低洼盐碱地原淡水养鱼池塘改建中国对虾养殖池塘，在池塘边上打井提供养殖用水，井水盐度一般在10－12左右；虾苗在水泥池淡化7天使盐度降为15，经暂养后陆续分至养殖池，暂养成活率76．11％；养成阶段主要使用配合饵料，添加抗病药物；前期以添加水为主，养殖中后期少量换水，平均日换水量不超过5％，并定期使用水质净化剂。结果5个养殖池对虾平均亩产90．83kg。     

云斑尖塘鳢♀×线纹尖塘鳢♂杂交育种的初步研究

利用从国外引进的云斑、线纹尖塘鳢的自繁后代,经过强化培育、性腺促熟后,2009年5-9月开展人工杂交试验。试验结果:孵化水温28~30℃时,云斑尖塘鳢♀×线纹尖塘鳢♂孵化时间68h,受精率为90.0%,孵化率为83.6%,培苗出苗率为60.51%,研究证明尖塘鳢属种间杂交可以成功。     

Replacement of fish meal by meat and bone meal in diets for large yellow croaker, Pseudosciaena crocea

A growth experiment was conducted to investigate the effects of replacement of fish meal (FM) by meat and bone meal (MBM) in diets on the growth and body composition of large yellow croaker (Pseudosciaena crocea). Six isonitrogenous (43% crude protein) and isoenergetic (20 kJ g^− 1) diets replacing 0, 15, 30, 45, 60 and 75% FM protein by MBM protein were formulated. Each diet was randomly allocated to triplicate groups of fish in sea floating cages (1.0 × 1.0 × 1.5 m), and each cage was stocked with 180 fish (initial average weight of 1.88 ± 0.02 g). Fish were fed twice daily (05:00 and 17:30) to apparent satiation for 8 weeks. The water temperature ranged from 26.5 to 32.5 °C, salinity from 32 to 36‰, and dissolved oxygen content was approximately 7 mg l^− 1 during the experimental period. Survival decreased with increasing dietary MBM and the survival in the fish fed the diet with 75% protein from MBM was significantly lower than other groups (P < 0.05). There were no significant differences in specific growth rate (SGR) among the fish fed the diets with 0 (the control group), 15, 30 and 45% protein from MBM. However, SGR in the fish fed the diets with 60 and 75% protein from MBM were significantly lower than other groups (P < 0.05). No significant differences in feeding rate were observed among dietary treatments. The digestibility experiment showed that the apparent digestibility coefficients (ADC) of dry matter, protein, lipid and energy of MBM were significantly lower compared with those of FM (P < 0.05). Essential amino acid index was found to be correlated positively with SGR in the present study, suggesting that essential amino acid balance was important. Body composition analysis showed that the carcass protein and essential amino acids were not significantly affected by dietary MBM. The lipid and n-3 highly unsaturated fatty acid (n-3 HUFA) in fish muscle, however, significantly decreased with increasing dietary MBM. These results showed that 45% of FM protein could be replaced by MBM protein in diets of large yellow croaker without significantly reducing growth. It was suggested that the reduced growth with higher MBM was due to lower digestibility and imbalance of essential amino acids.     

Effects of Salinity on Biogenic Amines,Hemolymph Osmotic Pressure,and Activity of Gill’s Na+/K+‐ATPase in Charybdis japonica (Crustacea,Decapoda)

The effects of salinity on hemolymph osmotic pressure, gill Na⁺/K⁺‐ATPase activity and dopamine (DA), norepinephrine (NE), serotonin (5‐HT) in the gills, and hemolymph of the adult Charybdis japonica were studied. DA levels increased significantly (P < 0.05), while the NE and 5‐HT revealed contrary change in hemolymph and gills. The iso‐osmotic point of C. japonica (911.4 mOsm/kg) was at salinity of 27.87 ppt. The Na⁺/K⁺‐ATPase activity of gill showed negative correlation with salinity in the hypotonic environment (<27.87 ppt). The results of this experiment indicated that C. japonica had great capability to acclimate to low salinity.     

棉酚对罗非鱼（Oreochromisniloticus）离体精子毒性作用的研究

新鲜采取的尼罗罗非鱼精液在加入棉酚的精子保存液中28℃下培养。高达10mM 的乙酸棉酚也不影响精子在一小时内的存活率。罗非鱼精子的存活率在培养三小时后存活率显下降，而低浓度棉酚（25－100μM）显提高罗非鱼精子的 存活率。 本对上述实验结果进行了讨论。     

新合院生活的景观体验——黄骅新城家园景观设计

文章从分析现状入手,依据建筑规划所形成的空间提出了新合院的景观设计理念,并通过对道路系统、出入口、水系、植物、老年儿童活动空间等景观空间的精心组织,形成小区一心、二街、三轴、四院的景观骨架,再结合对景、框景等造园手法来打造一个简洁朴实又不失特色的小区景观。     

Biochemical properties,molecular characterizations,functions, and application perspectives of phytases

As a kind of enzyme widely existing in eukaryotic species, especially in grains and oil seeds, phytases play an important role in the degradation of some phosphates containing organic molecules. So far, phytases derived from various species have been successfully used as animal feed additives. It has also been experimentally verified that phytases have a potential use in generating crop germplasm with high phosphorus use efficiency, based on their biochemical role in releasing Pi from the phytate and its derivatives. In this paper, the biochemical properties, molecular characterizations, functions and the potential application perspective of phytases are reviewed and commented on, aiming at the further exploration of the biochemical and molecular characterizations, and promotion of the application of phytases, a kind of important enzyme possessing potential use in animal feeding and creation of high P use crop cultivars, in the future.