套袋对红富士苹果果皮细胞超微结构的影响

红富士苹果果皮细胞超微结构的观察结果表明,未套袋颗粒果皮表层细胞叶绿体片层结构发育较套袋果实发达,至果实采收前,未套袋果液泡染色较深县均匀,而套袋果液泡染色深,呈絮状凝结,这可能是颗粒去袋后花青苷迅速合成,在液泡内大量积累所致。     

补饲青绿饲料对不同性别肉仔鸡皮肤色泽的影响

研究了在饲喂全价配合日粮基础上补饲青绿饲料对不同性别肉仔鸡全身不同部位皮肤色泽的影响。各组自由采食玉米-豆粕型基础日粮,分别于第1、15、29天开始补饲青绿饲料,比较分析42日龄时的全身各部位皮肤的色泽(L、a、b值)。结果表明,不同性别肉仔鸡各部位皮肤色泽间存在一定的差异性;补饲青绿饲料对肉仔鸡皮肤色泽的影响效应,以黄度最强和亮度最弱;补饲青绿饲料的时间越早,对肉仔鸡皮肤色泽的影响越明显;补饲青绿饲料对母肉仔鸡皮肤色泽的影响比对公肉仔鸡更显著。     

与苹果果皮红色性状相关的RAPD分子标记的筛选

用355条10bp随机引物来筛选与苹果果实红色性状连锁的分子标记。通过分离群体分组分析,在果实红色与非红色2个对比基因池间进行了扩增筛选,初步选出49个多态性引物,进一步对这些多态性引物进行群体上的分析发现S519可以扩增出大约1000bp左右的一条与红色性状相关的DNA特异带。对本研究的73个来自3个不同杂交组合的F1后代个体分析表明,该标记判断果实红色性状的符合率为76.7%。鉴于获得的多态性标记对果皮颜色预测的准确率不高的现状,我们采用了双标记组合分析方案,即用S5191000分别与以往获得的3个与果色性状相关的标记(S12891200、S12351000和S21071200)配对组合进行判断,从而使得标记对目标性状预测的正确性大为提高。另外,对总共获得的4个RAPD标记在9个栽培品种上进行了分析,大多数品种的表现与理论一致。     

黑皮中熟西瓜新品种开杂18号的选育

开杂18号是开封市农林科学研究所选育的黑皮、中熟西瓜新品种。全生育期103 d,果实发育期33 d,具有果个大、果皮黑且韧、品质优、易坐果、抗性强、适应范围较广等突出优点。     

网纹甜瓜新品种金蜜龙的选育

金蜜龙网纹甜瓜是天津科润蔬菜研究所选育的网纹甜瓜新品种。果实发育期50d,单果重1.5kg左右;果皮黄色,果面覆中等均匀网纹,果形指数1.2;果肉橙色,肉质脆嫩多汁,风味清香,中心可溶性固形物含量16%,肉厚3.9cm。商品率高,耐贮性好,适宜春季设施栽培。2006年10月通过国家甜瓜新品种鉴定。     

Induced and spontaneous IgE antibodies to Dermatophagoides farinae in dogs and cats: evidence of functional heterogeneity of IgE

Enzyme-linked immunosorbent assays (ELISAs) were developed to measure IgE antibodies specific for Dermatophagoides farinae in dogs and cats. Although higher levels were detected in atopic dogs and cats than in normal animals without skin disease, the differences were not statistically significant. On the other hand, levels in dogs and cats that were reared under laboratory conditions, and thus presumably not exposed to house dust mites, were either very low or undetectable. IgE antibodies were induced in 10 laboratory-reared cats using low-dose antigenic stimulation in aluminium hydroxide. All cats developed detectable IgE, but not all developed positive skin tests. However, serum from those cats with positive skin tests were able to give positive Prausnitz–Küstner (PK) tests. The canine data, together with previous work on basophil histamine release, suggests that the distinction between atopic and normal dogs may result from a heterogeneity of either IgE or of the high-affinity mast cell receptor. The feline data can only be explained by the existence of a heterogeneity of IgE.     

Inhibition of histamine release from dispersed canine skin mast cells by cyclosporin A, rolipram and salbutamol, but not by dexamethasone or sodium cromoglycate

Despite the important role that canine skin mast cells play in IgE-mediated allergic inflammation, clinically useful compounds for modulating mediator release from these cells or for suppressing cell response are lacking in the dog. The ability of five compounds to inhibit histamine release induced by non immunological (calcium ionophore A23187 and substance P) and IgE-dependent (concanavalin A) stimuli were compared. Sodium cromoglycate, a mast cell stabilizer, and dexamethasone, a glucocorticoid, failed to inhibit histamine release from isolated skin mast cells following any kind of stimulation. Salbutamol, a β-adrenergic agonist, exhibited inhibitory activity (46.0%) only after concanavalin A activation. In contrast, rolipram, a selective phosphodiesterase IV inhibitor and cyclosporin A, an immunosuppressor, showed potent anti allergic actions, inhibiting both IgE-dependent and -independent stimuli. Rolipram inhibited 42.8%, 44.7% and 19.2% of the mediator release induced by ionophore A23187, substance P and concanavalin A, respectively. Similarly cyclosporin A induced 85.9%, 14.9% and 67.3% inhibition after ionophore A23187, substance P and concanavalin A stimulation, respectively. These results suggest that rolipram and cyclosporin A merit to be clinically tested as agents for the treatment of chronic allergic diseases in the dog.     

牛蛙腐皮病病变皮肤亚显微结构的观察

为揭示牛蛙腐皮病的病理形态和发病的机理，采用透射电镜对病蛙不同病期的病变皮肤进行了观察，皮肤病变早期可见角化层脱落，状上皮细胞连接疏松，桥粒减少，随着病情发展细胞间隙增宽，桥粒进一步减少，细胞核固缩、溶解，细胞裂解；病变后期，表皮层崩解，真皮层胶原纤维溶解，炎症区有大量炎症细胞浸润，并可见吞噬了细菌的单核与中性粒细胞。     

"中华红又亮"对断奶仔猪的饲喂效果试验

试验选用体重约8kg的三元杂交猪(杜×长×大)60头,随机分成3组,每组2个重复,分别饲喂含不同剂量"中华红又亮"的饲粮,研究"中华红又亮"对仔猪生产性能、肤色的影响.结果表明,以"中华红又亮"取代饲粮中部分硫酸亚铁,可显著提高仔猪平均日增重(P＜0.05),显著降低料重比(P＜0.05),明显改善仔猪肤色.根据试验效果,仔猪饲粮中"中华红又亮"的添加浓度宜为3.0x10-.4 6.0x10-4.     

Influence of Graded Levels of Organic Zinc on Growth Performance and Carcass Traits of Broilers

This study investigated the effect of graded levels of organic Zn (Bioplex Zn) on growth performance and carcass traits of broilers fed diets containing organic Se (Sel-Plex). Dietary treatments consisted of adding 0, 15, 30, 45, or 60 ppm organic Zn to a basal diet containing 60 ppm Zn from an inorganic source. Feed and water were provided ad libitum. Body weight, feed intake, feed conversion, and carcass traits were evaluated. Carcass evaluation was also performed on the last day of the experimental period. Body weight, feed intake, feed conversion, and weights of individual meat cuts were not statistically influenced by increasing organic Zn levels in the diet. However, a significant increase in skin tearing strength was observed in response to increasing levels of dietary organic Zn. Zinc plays a role in epithelial cell layers and collagen synthesis, thus affecting susceptibility of skin to tearing. These data indicated that organic Zn does not affect growth performance of broilers but increases resistance of skin to tearing, therefore improving carcass quality.