鳙仔—幼鱼耳石日轮与生长的研究↑（*）

催产获得受精卵，从胚胎发育后期到秋季鱼种出塘的孵化饲养过程中，连续取样剖出矢耳后，其制片在光镜下观察耳石形态，大小，轮纹排列及其间距变化，部分耳石在扫描电镜下观察轮纹的细微结构，用实测体长体重和日轮退算体长及计算体重比较研究了生长特性。耳石形态经历了由圆形，椭圆形，菱形到梨形的变化过程，耳石直径与全长呈线性相关，其关系式为ｙ＝－０．１９４４＋０．０３８８ｘ。孵出后第二天出现第一个日轮，之后每日形成     

Primary cranial mediastinal hemangiosarcoma in a young dog

Primary cranial mediastinal hemangiosarcomas are uncommon tumors. A 30-kg, 2-year-old, intact female German shepherd was presented for evaluation of cachexia and respiratory distress of a few days’ duration. Lateral radiographic projection of the thorax revealed significant pleural effusion. Computed tomography revealed a cranial mediastinal mass effect adjacent to the heart. On surgical exploration, a pedunculated mass attached to the esophagus, trachea, brachiocephalic trunk, left subclavian artery and cranial vena cava without attachment to the right atrium and auricular appendage was removed and debrided by use of blunt dissection and dry gauzes, respectively. Histopathology results described the cranial mediastinal mass as hemangiosarcoma. At 8 months and 5 days post-operatively, the patient died. Primary cranial mediastinal hemangiosarcomas, although a seemingly rare cause of thoracic pathology in young dogs, should be considered in the differential diagnosis for pleural effusion and soft tissue mass effect in the cranial mediastinum. This is the first case report in a dog to describe primary cranial mediastinal hemangiosarcoma.     

Associations of Male Fertility Traits with Blood Groups and Blood Protein Polymorphisms in Dairy Cattle

Abstract

The relationships between 12 polymorphic systems and bull fertility were studied in the Swedish Red and White dairy cattle population. The material consisted of 1447 young bulls with non-return rates based on at least 500 inseminations each. A reduced animal model including a full additive relationship matrix was used. Multiple regressions were fitted for the estimation of the average gene substitution effects as well as the gene-frequency-independent effects of additive gene action and dominance. To evaluate the results a multivariate analysis of variance, classical segregation analyses and marker frequency studies were performed. Significant associations were found between the F, B, Tf, S and C systems, and nonreturn rates, but the contribution of the markers to the total variation of non-return rates was small.     

茉莉酸和水杨酸对热胁迫下葡萄幼苗抗氧化能力的影响

用50μmol/L茉莉酸和100μmol/L水杨酸预处理葡萄幼苗后,在高温胁迫下,蛋白质含量、抗坏血酸氧化物酶、谷胱甘酞还原酶活性呈现先升后降的变化趋势,抗坏血酸含量持续下降,茉莉酸和水杨酸预处理过的葡萄幼苗中可溶性蛋白质含量、抗坏血酸氧化物酶、谷胱甘酞还原酶活性和抗坏血酸含量与谷胱甘酞含量都高于对照。由此认为茉莉酸和水杨酸能减缓高温胁迫所引起的胁变反应。推测JA和SA处理在诱导葡萄抗热性能上可能具有相似的机理。     

覆草、覆膜对旱地苹果幼树生长发育的影响

果园土壤水分直接影响果树的生长发育。试验表明 ,覆草、覆膜效果明显好于清耕。果园覆草、覆膜后大大减少了土壤水分的蒸发 ,其土壤含水量分别比对照提高 2 3.4 4 % ,18.39% ;苹果树的根系活力、叶片相对含水量、新梢长度、叶面积大小、叶绿素含量等均高于对照 ,硝酸还原酶活性、光合强度比对照有明显提高 ,细胞质膜相对透性明显降低     

桑细菌性疫病菌[Pseudomonas syringae pv.mori(Boyer and lambert)Young et al]的冰核活性研究

对不同桑园桑疫病菌(Pseudomonas syringae pv.mori(Boyer andlambert)Young et al)菌株的冰核活性测定表明,冰核活性细菌占17.8%.冰核活性菌不能利用山梨醇,但能产生硫化氢;而无冰核活性菌株则相反.     

捆裹青贮燕麦草饲喂幼年羊的增重效果

捆裹青贮燕麦草饲喂幼年藏系羊 ,2次 /d ,平均采食 1 2 83kg/d·只 ,经 45d饲养试验 ,平均增重 2 48kg ,与饲喂燕麦干草的对照组相比 ,饲草转化率提高 8 2 0 %。     

Salicylic acid or heat acclimation pre-treatment enhances the plasma membrane-associated ATPase activities in young grape plants under heat shock

Proton pumps play an important role in the physiological activities of plants. Changes in membrane-associated H⁺- and Ca²⁺-ATPase activities in heat-shocked plants after heat acclimation (HA) or salicylic acid (SA) pre-treatment in annual young grape plants (Vitis vinifera L. cv. Jingxiu) were investigated. ATPase activity was assayed through biochemical analysis in which two-phase partitioning was used to purify plasma membranes and cerium trichloride was precipitated with an electromicroscopic cytochemical method. The plasmalemma H⁺- and Ca²⁺-ATPase activities were higher in HA- or SA-pre-treated plants than in controls. The stability of H⁺- and Ca²⁺-ATPase activities in pre-treated plants always remained at higher levels during subsequent heat shock treatment, which was consistent with the observations made using an electromicroscope. A number of cerium phosphate grains representing enzyme activity in HA- or SA-pre-treated plants were observed 6 h following heat shock, whereas no grains were found in control plants under the same conditions. These results suggest that the changes in the activities of plasma membrane H⁺- and Ca²⁺-ATPase contributed to the thermotolerance induced by either HA or SA pre-treatment in young grape plants and the two pre-treatments may have had the some same regulatory mechanism.