药用真菌发酵产物调控肉鸡内分泌及免疫力的研究

将药用真菌接种到以山芋渣为主并添加不同量的黄芪固态基质中进行发酵,获得发酵菌质,研究菌质对肉鸡内源性激素代谢、免疫力的影响。结果表明：菌质作为饲料添加剂饲喂AA肉鸡,对AA肉鸡的内源性激素有明显的调节作用,各试验组的生长激素浓度显著高于对照组（P〈0．05,P〈0．01）;试验1组的胰岛素、三碘甲腺原氨酸浓度显著高于对照组（P〈0．05）;试验2、3组的四碘甲腺原氨酸浓度显著高于对照组（P〈0．05,P〈0．01）;各试验组的皮质醇浓度低于对照组,但差异不显著。各试验组在配合疫苗使用的情况下,肉鸡血清中禽流感-H5亚型、新城疫抗体滴度显著高于对照组（P〈0．05,P〈0．001）;各试验组的免疫器官重量也比对照组高,说明菌质可提高肉鸡的免疫力。     

集约化养鸡场空气环境中生物气溶胶特点研究

为了给北京地区不同类型养鸡场空气环境中生物气溶胶的危害评价提供基础数据,对蛋鸡和肉鸡两种养殖方式下,鸡舍内外空气环境中生物气溶胶的浓度和粒径分布进行检测,并对大肠菌群和抗生素抗性菌进行了分析。结果表明,北京郊区(县)蛋鸡舍内,所调查的五种生物气溶胶(细菌、真菌、大肠菌群、四环素和红霉素抗性菌)浓度高于同地区肉鸡舍(P<0.05)。蛋鸡舍内空气中约50%的细菌气溶胶分别具有四环素和红霉素抗性;大肠菌群、四环素抗性大肠菌群和红霉素抗性大肠菌群的平均浓度分别为7.32×103、2.87×103CFU·m-3和3.31×103CFU·m-3。两种养殖方式下细菌和真菌气溶胶粒径分布规律有所差异,导致其在细颗粒物中所占比例不同。     

松突圆蚧生防菌不同喷施次数及用量对松突圆蚧的防治效果

[目的]探讨松突圆蚧生防菌在林间防治松突圆蚧的最适喷施次数和用量。[方法]2014—2015年在广西玉林市玉州区松突圆蚧疫区,开展了松突圆蚧生防菌不同喷施次数(0斤0次、每年7.50 kg/hm~2喷1次、每2年7.50 kg/hm~2喷1次)与不同喷施量(0、7.50、11.25、15.00 kg/hm~2)对松突圆蚧的防治试验。[结果]每年喷施1次7.50、11.25、15.00 kg/hm~2松突圆蚧病原真菌制成的菌粉均能有效防治松突圆蚧的发生,且它们之间防治效果无显著性差异。[结论]松突圆蚧生防菌粉每年喷施1次,每次7.50 kg/hm~2,即能在松突圆蚧盛发期对其进行有效防治,可在松突圆蚧防治中推广应用。     

碱蓬根系嗜盐耐盐真菌的分离与鉴定

为分析耐盐植物碱蓬根系真菌的组成和耐盐程度,采用常规植物组织真菌分离方法对盐碱地中生长健康的碱蓬根系进行真菌分离,将分离得到的真菌在不同NaCl浓度培养基上进行培养,检测菌株的嗜盐耐盐性,并对分离得到的嗜盐耐盐真菌进行形态学鉴定和分子生物学鉴定。结果显示:分离得到耐盐真菌40株,分别属于镰刀菌属(Fusarium sp.)、链格孢属(Alternaria sp.)、曲霉属(Aspergillus sp.)、腐霉属(Pythium sp.)等,其中,棘孢曲霉(Aspergillus aculeatus)和尖孢镰刀菌(Fusarium oxysporum)是没有被报道过的耐盐真菌;分离得到嗜盐真菌3株,都属于聚多曲霉(Aspergillus sydowii)。结果表明,耐盐植物碱蓬中嗜盐耐盐真菌多样性丰富。     

风化煤用量下覆膜和AM真菌对玉米生长和土壤微环境的影响

为缓解我国东部贫瘠土壤,以风化煤与覆膜为切入点,通过室内盆栽试验,研究两种覆膜方式(无覆膜和覆薄膜)和两个供试土壤基质(砂土基质和砂煤混合基质)下接种AM真菌对干旱胁迫时玉米生长特性、水分利用效率与土壤性状的影响。结果表明:两个覆膜方式下,砂煤混合基质相比砂土基质提高了接种AM真菌处理的玉米根系侵染率和土壤根外菌丝密度,但无明显差异;同时土壤总球囊霉素和易提取球囊霉素含量分别显著提高了80.0%~106.5%和55.0%~73.3%(P0.05)。同一覆膜方式下,砂煤混合基质接种AM真菌和CK处理的土壤有机碳、全氮与速效磷含量分别显著高于砂土基质下相应处理,但降低了土壤速效钾含量。砂煤混合基质下覆薄膜与接种AM真菌联合对玉米株高、生物量、叶片SPAD值及水分利用效率的促进效果最好;同时砂煤混合基质接种AM真菌处理提高了无覆膜下土壤蔗糖酶和全覆膜下过氧化氢酶和碱性磷酸酶含量,分别比砂土基质下处理显著提高了46.8%~59.8%、37.9%~70.0%与57.8%~87.5%(P0.05)。研究表明施加一定量风化煤时,接种AM真菌和覆薄膜能够促进水分胁迫下的植物生长发育,改善水分利用效率和提高土壤肥力。     

旱生条件下柠条锦鸡儿AM真菌生态学研究

通过从分布于山西、陕西和内蒙古三省区12个样地中的柠条锦鸡儿(Caragana korshinskii)根围采集土样和根样,系统研究了柠条锦鸡儿AM真菌种类组成和生态分布.试验结果表明,在已分离鉴定出的12种AM真菌中,球囊霉属(Glomus)6种,无梗囊霉属(Acaulospora)3种,巨孢囊霉属(Gigaspora)1种,盾巨孢囊霉属(Scutellospora)2种,而摩西球囊霉(Glomus mosseae)和缩球囊霉(Glomus constrictum)是优势菌种. AM真菌能与柠条锦鸡儿形成良好的共生结构,AM真菌平均总定殖率59.98%,平均孢子密度为830.59个/100 g土.不同采样地之间的AM真菌种类和分布差异显著.孢子密度与菌丝和总定殖率呈显著正相关;孢子密度与土壤速效N呈极显著正相关,丛枝定殖率与土壤有机质呈显著正相关,总定殖率和菌丝定殖率与土壤pH呈极显著正相关.     

新鲜牛粪便中食线虫真菌的分离和鉴定

从78个新鲜牛粪样中分离到4株食线虫真菌（nematophagous fungi)，通过对其菌丝体、孢子、捕食器官等的形态学观察、测定，2株鉴定为节丛孢属（Arthrobotrys)的寡孢节丛孢菌（A.oligospora)，1株为指状节丛孢菌（A.dactyloides),1株为圆锥状节丛孢菌（A.conoides)。     

捕食线虫性真菌18S rDNA基因序列与种系发生关系研究

对捕食线虫性真菌——少孢节丛孢菌A1分离株(Arthrobotrys oligospora A1)的18S rDNA基因序列进行了研究。结果表明：其18S rDNA全基因序列为1769bp，在进化树上与同种国外分离株A．oligospora var oligospora 1最为接近，同源性为94．7％。这与二者都具有捕食性结构—菌网的特点相一致。证实捕食线虫性真菌的捕食性结构与捕食线虫性真菌种系发生有关。从少孢节丛孢菌3个分离菌株(Arthrobotrys oligospora A1、A．oligospora 1、A．oligospora2)的进化树及同源性来看。不同国家地区的丛孢菌属(Arthrobotrys)分离株确实存在差异。     

Seasonal effects on the aerobic bacterial and fungal conjunctival flora of normal thoroughbred brood mares in Florida

Objective To evaluate seasonal effects on the presence or absence of fungal and aerobic bacterial flora of the conjunctival fornix of normal Florida Thoroughbred horses. Sample population Both eyes of 100 horses. Procedure Horses with normal anterior segment ophthalmic examinations from three farms in north central Florida were included. Each animal had the ventral conjunctival fornix of each eye swabbed with sterile culturettes. Samples were taken in October, January, April, and July (1999–2000). Aerobic and fungal cultures were plated. Bacterial cultures were reviewed at 24 and 48 h. Fungal cultures were reviewed weekly for 4 weeks. Logistic regression analysis with season as a factor and age of the horse as a covariate was performed. Statistical significance was set at P < 0.01. Results Horses ranged from 3 to 24 years of age, with a median age of 9 years. Twenty‐four genera of bacteria and 35 genera of fungi were recovered. Corynebacterium sp., Staphylococcus sp., Bacillus sp. and Moraxella sp. were the bacteria most frequently isolated. Mold species, dematiaceous mold species, Chrysosporium sp., Cladosporium sp., and Aspergillus sp. were the most frequently recovered fungi. Season did not have a significant effect on the presence of microorganisms isolated for individual horses adjusted for age. Younger horses had an increased incidence of gram‐negative rods and fungal isolates. The number of bacteria and fungi isolated are not uniform across seasons. Conclusion There were no significant differences between the number or type of organisms cultured during the sampling seasons in normal Florida horses. A large range of normal bacterial and fungal flora were isolated from these horses. The number of bacteria and fungi isolated are not uniform across seasons. The likelihood of detecting an organism depends on the horses’ age.