江西省不同生态条件对棉纤维品质的影响

不同生态区棉纤维品质测定,是全国优质棉基地县建设科技服务中的一个专题研究项目,目的在于了解全国不同生态棉区影响纤维品质的主要因子。江西省通过七个试点两个品种连续三年的试验研究,结果表明:地点间差异显著,主要受气候因素的影响.2.5％的跨长与开花后1～18天的雨量、光照和20～25℃的适宜温度天数呈正相关,但决定系数不大;比强度与开花后19～25天的雨量和≥32℃的高温天数呈负相关,与该阶段光照呈正相关;马克隆值与开花后19～25天的雨量和收花前<16℃的低温天数呈负相关,与开花后26天至收花时的适宜温度(20～25℃)天数呈正相关。江西棉纤维偏粗主要与伏旱明显及持续高温有关,其次是土壤肥力差异.同一品种的棉纤维品质,以中、下部铃好于上部铃,正常年份好于灾年(或旱年),平原洲地棉区好于丘陵红壤旱地.说明因地制宜地选用良种和优化栽培措施,对提高棉纤维品质有着积极的指导意义。     

Modelling the influence of stand structural,edaphic and climatic influences on juvenile Pinus radiata fibre length

The objectives of this study were to determine the influence of site, fertilisation and age on fibre length and develop predictive models of fibre length from a comprehensive set of climatic, edaphic and stand variables. Data were collected from a nationwide set of 22 site quality plots where Pinus radiata D. Don was established at high stand densities (40 000 stems ha⁻¹) and grown over a period of 4 years. The main environmental drivers of fibre length were identified by assessing the strength of bivariate correlations and use of multiple regression. Path analysis was used as an extension to multiple regression to separate cause from effect and quantify the direct influence of variables significantly related to fibre length.     

Postnatal changes in electromyographic signals during piglet growth, and in relation to muscle fibre types

This study uses non-invasive evoked surface electromyography (SEMG) to investigate postnatal muscle development in pigs, and to assess any correlation between recorded signal parameters and muscle fibre types in two different skeletal muscles. Four litters (n = 43) of Large White × Landrace pigs were used. Evoked SEMG measurements were taken on days 2, 5, 14, 26, 60 and 151 post partum from m. Longissimus dorsi (LD) and on days 14, 26, 60 and 151 post partum from m. Biceps femoris (BF). A third of each litter was slaughtered at days 27, 61 and 153 post partum. Biopsy samples for LD and BF were taken to categorize muscle fibre types. For LD there was a significant increase in compound muscle action potential (CMAP) parameters from day 2 to day 5 post partum, whilst for BF significant increases occurred from days 14 to 26 post partum. Fibre type development in both muscles showed a significant decrease in type IIA fibre number (P < 0.001) and an increase in type IIB fibre number (P < 0.001). Analysis of CMAP parameters in relation to fibre type percentages showed significant positive correlations between percentage of type I fibres in BF and CMAP Area (r = 0.71; P = 0.05), SlopeL (r = 0.79; P = 0.02) and Corr Peak (r = 0.78; P = 0.02) and a negative correlation with SlopeT (r = 0.89; P = 0.003) at day 151. A greater CMAP Area and Corr Peak as well as steeper leading and trailing slopes were on the other hand correlated to fewer type IIB fibres.

It is concluded that 1) changes in the evoked CMAP are muscle-specific during early postnatal development in the pig, and 2) in spite of a small sample size, the correlations between CMAP signal parameters and fibre type percentages warrant further investigation.     

陆地型长绒棉新种质F2代主要经济性状相关及通径分析

陆地型长绒棉亲本98301与高产亲本石远321杂交,对F2分离群体Len（2．5％跨长）、Un（纤维整齐度）、Str（束纤维拉力,g／tex）和Mic（麦克隆值）4个纤维品质性状及单株籽棉产量（霜前）、单株皮棉产量（霜前）、衣分、单株铃数（霜前收获铃数）、单铃重、籽指、青铃率7个产量性状间相关系数和通径系数进行分析。结果表明,Un与Str和Mic分别呈极显著正相关,Un与Len为显著负相关;Len与Str为极显著正相关;Str与Mic为负相关。Un与籽棉产量、皮棉产量、衣分和单株铃数间均呈极显著或显著正相关;Len与籽指、单铃重和青铃率间为正相关,而与衣分间为负相关;Str与籽指和青铃率之间为显著正相关;Mie与单株铃数和籽指间为正相关。通径分析表明,与皮棉产量有正向直接作用的性状是单株铃数〉单铃重〉衣分〉籽指。4个纤维品质性状中以Mic与皮棉产量间的负向直接作用最为重要,Str对皮棉产量直接作用为正值,它通过单株铃数、单铃重及Mic对产量的间接作用均为正值;Len通过单铃重和铃数对皮棉产量的正向间接作用有利于实现育种目标,而Len通过衣分对皮棉产量的负向间接作用在后代选择时应加以重视。     

Nutrient digestibilities and gut function in Atlantic salmon (Salmo salar) fed diets with cellulose or non-starch polysaccharides from soy

Duplicate groups of Atlantic salmon (Salmo salar), kept in saltwater, were fed fish meal based cold-pelleted diets where graded levels of native or extruded non-starch polysaccharides (NSP) from soybeans replaced cellulose, at a total NSP level of 100 g kg^− 1 for 28 days. The study also included a diet where defatted soybean meal (SBM) constituted the NSP at a level of 100 g kg^− 1 and a reference diet without NSP supplementation.The SBM diet resulted in a significant reduction in faecal dry matter content, apparent digestibilities of starch and organic material, and growth, and an increased faecal output of several elements (K, Na, Zn), compared to all the other diets. Morphological changes were only seen in the intestine of the fish fed the SBM, i.e. the diets holding purified soy-NSP did not induce enteritis. When compared to the diet without NSP, cellulose addition increased faecal dry matter, while inclusion of native soy-NSP reduced it. Dry matter in faeces and apparent digestibility of crude protein decreased in a linear manner, while the digestibility of starch and faecal output of K and Na increased linearly when native soy-NSP replaced graded levels of cellulose from 0 to 100 g kg^− 1 feed. When diets with 75 or 100 g kg^− 1 of native NSP and extruded soy-NSP were compared, fish fed native soy-NSP had reduced faecal dry matter, higher digestibility of starch, and increased faecal output of Cu, Fe, and K. Dry matter in faeces and faecal output of Cu was lower for the highest inclusion level, while digestibility of starch and faecal output of Mn and K were higher.In conclusion, soy-NSP was inert compared to the fish meal reference, with respect to nutrient digestibilities and intestinal pathologies, but affected faecal mineral excretion in Atlantic salmon.     

麻类作物副产品的综合利用现状

利用红麻全杆制浆造纸已进入生产阶段；利用苎麻壳，杆和红麻骨培养营养丰富的食用菌已推广应用，此外。利用麻骨压制人造纤维板和生产活性炭，苎麻叶，红麻叶用作饲料；苎麻根，大麻籽仁，剑麻叶提取物的药用等已应用于生产实践，麻类作物副产品的利用价值潜力巨大。     

天祝白牦牛被毛纤维类型分析研究

天祝白牦牛被毛有髓毛、两型毛、无髓毛均因部位不同其含量、细度和长度有较大的差异。纤维类型分析发现 ,天祝白牦牛被毛的绒毛中 ,存在外形 (长度和细度 )特征明显不同的两种无髓毛纤维 (绒毛 ) ,并将其分为无髓粗绒和无髓细绒。无髓粗绒的细度为 46 43 μm± 7 89μm ,无髓细绒的细度为 2 2 76μm± 3 91μm ,二者之间平均直径相差 2 3 67μm ,各部位无髓粗绒与无髓细绒在细度上有极显著的差异 (P <0 0 1)。无髓粗绒和无髓细绒的平均伸直长度分别为 8 92cm±3 97cm和 5 2 1cm± 1 17cm ,各部位也存在显著差异。因此 ,首次提出将天祝白牦牛的被毛中的无髓毛 (绒毛 )纤维分为无髓粗绒毛和无髓细绒毛两种纤维类型。     

木麻黄木材纤维形态株内变异的研究

对福建沿海木麻黄株内不同高度、圆周不同方位和不同年轮木材纤维长度、宽度、长宽比差异进行测定分析,结果表明;在株内不同高度、圆周不同方位上纤维形态差异不显著;不同年龄间纤维形态差异显著;纤维形态与年龄呈显著正相关。     

鸡腺胃型传染性支气管炎病毒HN毒株理化特性鉴定

ＨＮ毒标为从我省某鸡场患有呼吸道症状和腺胃病变的病鸡只以一的株病毒,在鸡胚中能稳定传代并且有规律性死亡和典型胚胎病变特征。ＨＮ毒株对热、乙醚和氯仿敏感,耐酸（ＰＨ３．０）、耐碱（ＰＨ１１．０）,能低抗１％胰蛋白酶,能在鸡胚中干扰鸡新城疫病毒Ｌａ Ｓｏｔａ株的增殖。试验结果表明,ＨＮ毒株的理化生支气管炎病毒相会。