Comparison of three different inhalant anesthetic agents (isoflurane, sevoflurane, desflurane) in red-tailed hawks (Buteo jamaicensis)

Objective To compare isoflurane, sevoflurane and desflurane for inhalant anesthesia in red‐tailed hawks (Buteo jamaicensis) in terms of the speed and characteristics of induction; cardiovascular and respiratory parameters while anesthetized; and speed and quality of recovery. Study design Prospective, cross over, randomized experimental study. Animals 12 healthy adult red‐tailed hawks. Methods Anesthesia was induced with isoflurane, sevoflurane or desflurane in oxygen via face mask in a crossover, randomized design with a 1 week washout period between each treatment. Hawks were tracheally intubated, allowed to breathe spontaneously, and instrumented for cardiopulmonary monitoring. Data collected included heart rate, respiratory rate, end‐tidal CO₂, inspired and expired agent, SpO_2, temperature, systolic blood pressure, time to intubation and time to recovery (tracking). Recovery was subjectively scored on a 4 point scale as well as a summary evaluation, by a single blinded observer. Results No significant difference in time to induction and time to extubation was noted with the administration of isoflurane, sevoflurane or desflurane. Time to the ability of the bird to follow a moving object with its eyes (tracking) was significantly faster with the administration of sevoflurane and desflurane. All recoveries were scored 1 or 2 and were assessed as good to excellent. No significant difference was noted in heart rate, blood pressure and temperature among the three inhalants. Administration of isoflurane resulted in lower respiratory rates. Conclusions and clinical relevance Overall, although isoflurane remains the most common inhaled anesthetic in avian practice, sevoflurane and desflurane both offer faster time to tracking, while similar changes in cardiopulmonary function were observed with each agent during anesthesia of healthy red‐tailed hawks.     

草原红牛胎儿成纤维细胞的分离培养及性别鉴定

为了获得高质量的草原红牛胎儿成纤维细胞,试验以发育40 d的草原红牛胎儿为材料,采用组织块贴壁法及胶原酶消化法分离纯化草原红牛胎儿成纤维细胞,并绘制生长曲线,再以SRY基因为模板设计性别鉴定引物,通过对已知性别草原红牛血液基因组PCR扩增检验所设计引物的性别特异性,最后采用基因组PCR方法鉴定分离得到的成纤维细胞的性别。结果表明:成功分离纯化出草原红牛胚胎成纤维细胞,经基因组PCR检验该细胞株性别为雄性。     

禽类红细胞免疫功能与疾病研究进展

红细胞(RBC)表面含有许多免疫相关物质,如Ⅰ型补体受体(CR-1)、Ⅲ型补体受体(CR-3)、淋巴细胞功能相关抗原-3(LFA-3)、人类补体膜辅助因子蛋白(MCP)、衰变加速因子(DAF)、过氧化物歧化酶(SOD)等,这些免疫相关物质不仅使RBC具有识别、存储、递呈抗原、清除免疫复合物(IC)、促进吞噬细胞的吞噬功能等作用,而且自身还具备完整的自我调控系统,广泛参与机体内的各种免疫反应,是机体免疫系统的重要组成部分。RBC这种参与机体免疫调控的功能使RBC在许多疾病的发生、发展过程中发挥重要作用,近年来国内外学者对RBC免疫功能的研究逐渐成为热点。     

文蛤SRBI基因变异与红壳色性状的关联性

为了解文蛤体内类胡萝卜素代谢相关基因清道夫受体B类I(Mm-SRBI)与红壳色形成的关联性,采用直接测序法对基因编码区进行SNP筛查和关联分析,并用免疫荧光、蛋白免疫印迹分析了Mm-SRBI蛋白在红、白壳色文蛤外套膜中的表达差异。结果显示,在Mm-SRBI基因的编码区筛选到15个SNP位点,位于保守序列上的4个突变位点c.647C/T、 c.723A/G、 c.818C/T、 c.1037A/G与红、白壳色存在显著关联,其中c.723A/G位点为非同义突变(异亮氨酸突变为缬氨酸),且4个位点在遗传上存在强连锁性;蛋白免疫印迹与免疫荧光结果表明,Mm-SRBI在红壳中的蛋白表达量显著高于白壳文蛤,主要表达部位为外套膜边缘膜的纤毛处。研究表明,Mm-SRBI基因的高表达与变异可能导致文蛤对类胡萝卜素的代谢产生差异,从而在生长发育过程中导致红壳色的形成。     

Different levels of organic trace minerals in diets for Nile tilapia juveniles alter gut characteristics and body composition,but not growth

Thirty groups of twenty juveniles each of Nile tilapia (Oreochromis niloticus, initial average weight 23.93 ± 0.80 g) were fed diets containing increasing amounts (0%, 25%, 50%, 75%, and 100% of levels used by the tilapia feed industry) of organic trace mineral (Fe, Zn, Mn, Cu, Se) supplementation for 56 days. Growth was not affected by the dose of mineral supplementation. However, body protein increased in fish fed intermediate doses of organic minerals, reaching a maximum at 40.44% supplementation. Doses >50% showed mild damage to the intestinal tissue. Body Fe, Zn and Cu deposition were highest at 28.32%, 24.43% and 78.45% supplementation, respectively. Tilapia could modulate intestinal morphology when fed different doses of organic minerals. As the supplementation doses increased, hemosiderin staining increased in the distal intestine and total body Fe content, indicating that the distal region of the intestine plays an important role in iron excretion by tilapia. Supplementation of organic trace minerals at intermediate doses does not harm Nile tilapia growth, but excessive trace mineral supplementation can impair body protein retention and promote histological alterations in the gut.     

Plasmid‐mediated antimicrobial resistance in motile aeromonads from diseased Nile tilapia (Oreochromis niloticus)

For the sustainable farming of tilapia, proper maintenance of their health and adequate treatment for infections at appropriate time are inevitable. The indiscriminate use of antibiotics in aquaculture, as a part of treatment and as growth promoters, accelerates antimicrobial resistance (AMR) among the fish pathogens. In the present study, we have isolated diverse aeromonads from Nile tilapia and studied their antibiogram and plasmid profiling. Aeromonas hydrophila, Aeromonas veronii, Aeromonas sobria, Aeromonas dhakensis, Aeromonas caviae, Aeromonas jandaei and Aeromonas aquatica were isolated from infected tilapia (n = 150), and their Shannon wiener diversity index was calculated as 1.926. A. veronii was found to be the most multiple antibiotic‐resistant pathogen with the MAR index of 0.46, and A. aquatica was noticed as the least resistant isolate. The minimum inhibitory concentration of resistant antibiotics was shown as >256 mcg/ml for most of the isolates. The virulent genes such as aerolysin and hemolysin were identified in all the isolates except A. aquatica. The detection of class 1 integrons, plasmid profiling and plasmid curing studies confirmed that AMR exhibited by most of the Aeromonas species is of plasmid mediated. This challenges the risk of wide spread of AMR among the pathogens and subsequent treatment of the infection.     

不同施肥处理对红三叶青干草品质的影响

以岷山红三叶Trifolium pratense为供试材料,通过小区试验,研究了3个水平的氮肥[0(A1)、75(A2)和150(A3)kg/hm2]和3个水平的磷肥[0(B1)、120(B2)和360(B3)kg/hm2）的互作效应对岷山红三叶青干草品质的影响。结果表明,A3B2处理的粗蛋白含量、钙含量最高,分别比对照高2.5%和0.14%;A1B3处理的粗灰分、磷含量最高,分别比对照高1.2%和0.45%,而中性洗涤纤维含量最低,比对照低2.1%;A1B2处理的酸性洗涤纤维含量最低,比对照低1.5%。试验结果表明,岷山红三叶的施肥量为A3B2（氮肥150 kg/hm2,磷肥120 kg/hm2）时,青干草品质最好。     

NaClO和蔗糖溶液对红三叶种子发芽特性的影响

研究了不同浓度NaClO和蔗糖溶液对红三叶种子发芽的影响。结果表明,用0．2％NaClO溶液处理虹三叶种子15min,种子的发芽率最高,为60．6％;用0．2％NaClO溶液处理红三叶种子10min的带茵率最低,为0．41％。红三叶种子在没有添加蔗糖溶液的1／2MS培养基中发芽率最高,但长势较差;加入20g／L蔗糖的培养基中,虽然发芽率稍低,但生长良好,并有明显的毛根分化。     

利用红边参数估计叶片叶绿素含量

Hyperspectral remote sensing makes it possible to non-destructively monitor leaf chlorophyll content (LCC). This study characterized the geometric patterns of the first derivative reflectance spectra in the red edge region of rapeseed (Brassica napus L.) and wheat (Triticum aestivum L.) crops. The ratio of the red edge area less than 718 nm to the entire red edge area was negatively correlated with LCC. This finding allowed the construction of a new red edge parameter, defined as red edge symmetry (RES). Compared to the commonly used red edge parameters (red edge position, red edge amplitude, and red edge area), RES was a better predictor of LCC. Furthermore, RES was easily calculated using the reflectance of red edge boundary wavebands at 675 and 755 nm (R675 and R755) and reflectance of red edge center wavelength at 718 nm (R718), with the equation RES = (R718－R675)/( R755－R675). In addition, RES was simulated effectively with wide wavebands from the airborne hyperspectral sensor AVIRIS and satellite hyperspectral sensor Hyperion. The close relationships between the simulated RES and LCC indicated a high feasibility of estimating LCC with simulated RES from AVIRIS and Hyperion data. This made RES readily applicable to common airborne and satellite hyperspectral data derived from AVIRIS and Hyperion sources, as well as ground-based spectral reflectance data.     

几种水蚀阻断措施对坡地红壤干旱的影响

通过田间试验,研究了带状牧草、稻草覆盖和聚丙烯酰胺(PAM)表施及其组合措施对坡地红壤0-45cm土层干旱的影响。结果表明,各种水蚀阻断措施都能明显提高坡地红壤表层的土体贮水量;措施之间保水效果的差异在多雨阶段较小,而干旱阶段较大,且随土层深度增加而变大;水蚀阻断措施能够降低土体干旱发展速度,减轻土壤干旱,从而减轻作物干旱,增加其产量;PAM表施和稻草覆盖的保水抗旱效果要明显好于带状牧草。PAM表施、稻草覆盖分别与带状牧草组合以后,保水效果都有所减弱。