除臭微生物分离和筛选方法的改进与应用

为减轻大量的禽畜废弃物对环境的污染和促进其有机肥转化的进程,在以往大量研究的基础上,改进了分离和筛选除臭微生物的方法。应用该简便方法,快速地从环境中分离和筛选出除臭微生物F468,能够降低新鲜鸡粪氨气和硫化氢释放量分别在67%和56%以上,降低风干鸡粪氨气和硫化氢释放量分别在90%和52%以上。通过形态学方法鉴定,F468初步被鉴定为绿色木霉。     

应用微生物与秸秆降低鸡粪氨气释放量

为减轻大量禽畜废弃物中氨气流失对环境的污染,研究和优化了微生物与秸秆等辅料对氨气释放量的影响。结果表明,F468、M1?M9等除臭微生物能显著降低氨气的释放量,其中F468是最优微生物,其它微生物与F468的配伍并没有显著增强F468降低氨气释放量的能力,有些微生物还降低了其能力,因此选择单一微生物法降低氨气释放量。单独添加辅料对降低氨气的释放影响较小,辅料与微生物的配伍可大量降低氨气的释放量。5%的F468与10%的秸秆配伍在1?5 d降低88%的释放量。应用微生物与秸秆不仅降低氨气挥发对环境的危害,也是秸秆资源化利用的有效途径之一。     

鸡粪对铜污染土壤微生物生物量碳的影响

采用室内恒温好气培养法,研究了2．0％、4．0％、6．0％添加量鸡粪对铜污染土壤微生物生物量碳的影响。结果表明：向土壤中施入2．0％、4．0％、6．0％的鸡粪后,有机碳总量比对照分别增加了0．85、1．49、2．04倍,而可浸提有机碳含量分别增加了3．13、5．70、8．23倍,鸡粪的添加促进了土壤可浸提有机碳含量的增加,土壤可浸提有机碳含量和鸡粪添加量呈正相关（r=0．994^＊＊,n=12）。各处理土壤有机碳和可浸提有机碳含量随培养时间逐渐下降,90d后有机碳含量趋于稳定;土壤可浸提有机碳含量120d后趋于稳定。鸡粪显著促进了土壤微生物生物量碳含量和土壤微生物商的增加（P〈0．01）,与对照相比,2．0％、4．0％和6．0％鸡粪处理土壤微生物生物量碳含量分别增加2．88、5．19、6．98倍,土壤微生物生物量碳（SMBC）含量和土壤微生物商（SMQ）都与鸡粪的添加量呈正相关（rSMBC=0．998^＊＊,rSMQ=0．858,n=12）。在培养过程中士壤微生物生物量碳与土壤微生物商都呈现先下降再升高再下降的趋势。在培养试验的早期,鸡粪的添加有利于缓解铜污染土壤微生物生物量碳的下降,添加鸡粪的处理在培养的第10d后土壤微生物生物量碳含量开始上升,而对照则在30d以后才开始上升;添加鸡粪的处理在培养前期微生物生物量碳的最大下降幅度分别为：2．0％处理（52．74％）、4．0％处理（45．92％）、6．0％处理（55．52％）,而对照的下降幅度为92．02％。培养后期添加鸡粪处理土壤微生物生物量碳仍保持较高的水平。     

驯养中缅树鼩的消化道寄生虫监测及寄生蠕虫驱虫效果

目的了解野外树鼩和驯养树鼩寄生虫感染情况及其驱虫效果。方法 随机选取野外捕获3 d和已驯1个月(未驱虫)、F1代、F2代、F3代树鼩,各五笼,每笼3～4只,用饱和食盐水漂浮法检查粪样虫卵或卵囊,根据形态学鉴定虫种。结果粪样共检获两种寄生性线虫虫卵(毛尾线虫和奇口线虫)、膜壳绦虫卵、一种球虫卵囊。野外捕获3 d和驯养1个月树鼩的线虫卵检出率最高,达100%;绦虫卵检出率分别达60%和20%;球虫卵囊检出率分别达40%和20%。驯养F1代、F2代、F3代树鼩,仅F2代1笼检出线虫卵,检出率为20%。驱虫当天粪样检出的线虫虫卵、绦虫卵和球虫卵囊与驱虫前检出结果比例一致,并收集到39条奇口线虫、3条毛尾线虫、18条长膜壳绦虫。驱虫后第2天和第3天均未收集到虫体,粪样中也未检测到线虫卵和绦虫卵,仅检测到球虫卵囊。结论为树鼩实验动物化的消化道寄生虫病的监测和控制提供基础信息。     

冷藏对米蛾卵液中游离氨基酸变化的影响

赤眼蜂的工厂化繁育常使用米蛾卵作为中间寄主卵,为了满足赤眼蜂生产的需要,需对米蛾卵进行冷藏,但冷藏米蛾卵影响赤眼蜂的生长发育。利用核磁共振技术(NMR)测定了新鲜米蛾卵(U)、新鲜杀胚米蛾卵(CK)、杀胚米蛾卵在4℃条件下冷藏15 d(N15)、30 d(N30)、45 d(N45)和60 d(N60)后,米蛾卵卵液游离氨基酸种类和含量的变化。结果共鉴定到24种游离氨基酸及其衍生物,包括昆虫发育必需的10种氨基酸。U和CK之间的游离氨基酸组分没有显著差异,N15、N30和N45游离氨基酸总量随冷藏时间的延长而显著升高,N60中的氨基酸总量与N45比较没有显著增加。对24种游离氨基酸及其衍生物的含量进行主成分分析,结果表明丙氨酸、谷氨酰胺、鸟氨酸、天冬氨酸、组氨酸、赖氨酸、丝氨酸、焦谷氨酸等8种氨基酸的含量随冷藏时间的增加而有着显著的变化,其中,丙氨酸变化幅度最为明显,随着冷藏时间的增加,含量从0.1624 mmol/L增加到8.6192 mmol/L;组氨酸在N30、N45和N60处理之间显著下降,从0.7553 mmol/L降低到0.2495 mmol/L。因此,冷藏会导致米蛾卵内游离氨基酸含量发生一定变化,这可能是冷藏米蛾卵影响赤眼蜂生长发育的重要原因之一。     

集约化养殖禽畜粪中主要化学物质调查

对广东省集约化养殖场61个禽畜粪样本进行调查的结果表明,鸡粪和猪粪的总N、P、K含量均明显高于传统养殖,鸡、猪和鸽粪的P/N比高于一般作物的P/N比;3种禽畜粪总盐分含量分别为49.0、20.6和60.3 g·kg^-1,盐分组成以K和Na的硫酸盐和氯化物为主;鸡粪Cu、Zn和As的平均含量分别为107.5、366.6和21.6 mg·kg^-1;猪粪分别为765.1、1128.0和89.3 mg·kg^-1;鸽粪分别为56.1、210.9和2.9 mg·kg^-1.这3种禽畜粪的Pb、Cd和Cr含量均很低,在未检出至12.0 mg·kg^-1之间.按不同肥料重金属限量标准,鸡粪和猪粪重金属超标以Cu、Zn和As为主,其中Zn的超标最为普遍.     

两种微生物菌剂对西番莲果渣高温堆肥腐熟进程的影响

研究了在西番莲果渣堆肥体系中加入两种微生物菌剂（福贝和榕风）后的温度、C／N、NH4^＋ -N和NO3^- -N的动态变化及对西番莲果渣堆肥产品品质的影响．结果表明,在西番莲果渣中加入微生物菌剂能增加高温分解持续时间,加快物料C／N降低的速率,促进NH4^＋ -N向NO3^- -N转化,加快西番莲果渣堆肥腐熟化进程．添加福贝和榕风菌剂后,堆肥高温持续时间分别比对照（4d）增加7d和8d;腐熟后堆肥的NO3^- -N浓度分别比对照增加58．0％和64．2％．添加菌种显著增加了西番莲果渣堆肥的N、P、K养分含量,降低了堆肥容重,提高了堆肥总孔隙度和持水孔隙度,改善了堆肥产品的品质．两种菌剂间对西番莲果渣高温腐熟进程的影响没有显著差异,但福贝菌剂更有利于改善堆肥品质．     

3种苯并咪唑类药物对大熊猫西氏贝蛔虫的驱虫效果初步观察

西氏贝蛔虫Baylisascaris schroederi是圈养大熊猫Ailuropoda melanoleuca最常见、危害最严重的一种体内寄生虫,采用药物驱虫是目前控制圈养大熊猫蛔虫病的主要措施。为了筛选有效的驱虫药物,本研究观察了3种苯并咪唑类药物(阿苯达唑片剂、芬苯达唑膏剂和甲苯咪唑片剂)对大熊猫蛔虫的驱虫效果,统计了驱虫前后粪检蛔虫卵转阴率及排虫情况。结果表明,除芬苯达唑按5 mg·kg^-1体质量口服,每天1次,连续服用2 d,效果较差外,3种药物按10 mg·kg^-1体质量口服,每天1次,连续服用2 d,用药安全且有较好的驱虫效果。     

三江平原小叶章湿地枯落物初期分解动态

通过4周淋洗分解试验,探讨了微生物活动和淋洗作用对三江平原沼泽湿地沼泽化草甸小叶章和湿草甸小叶章枯落物初期分解的影响.结果表明：两种小叶章植物初期分解的质量损失分别占当年分解物质损失量的59％和22％,28 d分解后枯落物残留量明显降低,并呈先快后慢的变化过程.两种枯落物中N、P含量均有明显下降,N含量分别下降了约3265%和2455%,P下降了36.71%和45.15％.抑制微生物处理的枯落物N、P含量较不抑制处理高,但差异不显著;抑制和不抑制微生物处理下枯落物释放到淋洗液N、P含量变化也不相同,但差异未达到显著水平.表明小叶章初期分解主要受淋洗作用的影响.两种小叶章植物的分解速率和养分损失速率差异均未达到显著水平.     

奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟评价

对奶牛粪好氧堆肥过程中不同含碳有机物的变化特征以及腐熟程度进行了研究。根据腐熟指标(温度、种子发芽率、种子发芽指数、大肠杆菌以及蛔虫卵死亡率)的要求,奶牛粪经过堆肥后能够达到腐熟要求。堆肥过程中全碳、易氧化有机碳呈逐渐下降趋势,腐殖酸碳呈逐渐增加的趋势;微生物量碳和水溶性碳呈先增后降而后平稳的变化趋势;氧化稳定系数和H/F比(胡敏酸与富里酸比值)呈先降后增的变化趋势,而胡敏酸的E4/E6值(465和665nm处吸光系数比值)与氧化稳定系数和H/F比变化趋势相反。通过相关性分析发现,堆肥过程中易氧化有机碳和腐殖酸碳是影响全碳变化的主要因素;易氧化有机碳、腐殖酸碳、氧化稳定系数、H/F比、E4/E6值均能很好地表征奶牛粪堆肥的腐殖化和稳定化程度;微生物量碳和水溶性碳之间存在相互转化的关系。     

Nitrogen losses from perennial grass species

Nitrogen losses from plants may occur through a variety of pathways, but so far, most studies have only quantified losses of nutrients by above-ground litter production. We used ¹⁵N pulse labelling to quantify total nitrogen losses from above- and below-ground plant parts. Using this method we were able to include also pathways other than above-ground litter production. To test the hypothesis that species from nutrient-poor habitats lose less nitrogen than species from more fertile soils, six perennial grasses from habitats with a wide range of nutrient availability were investigated: Lolium perenne, Arrhenatherum elatius, Anthoxanthum odoratum, Festuca rubra, F. ovina and Molinia caerulea. The results of an experiment carried out in pots in a green-house at two fertility levels show that statistically significant losses occur through pathways other than above-ground litter production. In the low fertility treatment, most (70%) losses from L. perenne occurred by litter production, but in Ar. elatius, F. rubra, F. ovina and M. caerulea, more than 50% of labelled N losses took place by root turn-over, leaching or exudation from roots. When nutrient supply increased, the ¹⁵N losses in above-ground dead material increased in all species and in Ar. elatius, A. odoratum and F. rubra the ¹⁵N losses via other pathways decreased. Ranked according to decreasing turnover coefficient the sequence of species was: L. perenne, A. odoratum, F. rubra, F. ovina, Ar. elatius, M. caerulea. These results suggest that species adapted to sites with low availability of nutrients lose less nitrogen (including above- and below-ground losses) than species adapted to more fertile soils.     

Effects of carbonized and dried chicken manures on the growth, yield, and N content of soybean

The present study was conducted to investigate the effects of nitrogen derived from dried or carbonized chicken manure on growth, nodulation, yield and N content of soybean. ¹⁵N labeled chicken manure used in this study was obtained from the droppings of chicken fed on hulled rice grown under field conditions and fertilized with ¹⁵N-labeled stable isotope ammonium sulphate and potassium nitrate fertilizers. Carbonized chicken manure was made by heat treatment in a muffle furnace in our laboratory. This study was conducted in pots filled with clay loam soil. Results from the study show that the application of carbonized chicken manure increased soybean seed yield by 23% and 43% for the 50 and 100 kg N ha⁻¹ rates respectively. Dried chicken manure application increased soybean seed yield by 7% and 30% for the 50 and 100 kg N ha⁻¹ rates respectively. There was no difference in the N manure yield of both manures when applied at the same rate. The percentage ¹⁵N recovery was 17.6% and 8.9% for carbonized chicken manure, 19.2% and 10.5% for dried chicken manure at 50 and 100 kg N ha⁻¹ rates respectively at peak flowering stage of soybean growth. We found high total nitrogen yields of soybean at the rate of 100 kg N ha⁻¹ for both manures. There was a positive relationship between number of nodules and seed yield of soybean. Total N content also showed positive relationship with number of nodules and seed yield of soybean. We supposed that the higher P content of carbonized chicken manure is responsible for the higher seed yield and nodule growth compared to dried chicken manure.     

Automated electrical impedance technique for rapid enumeration of fecal coliforms in effluents from sewage treatment plants.

Fecal coliforms growing in a selective lactose-based broth medium at 44.5 degrees C generate a change in the electrical impedance of the culture relative to a sterile control when populations reach 10(6) to 10(7) per ml. The ratio of these changes was measured automatically, and the data were processed by computer. A linear relation was found between the log10 of the number of fecal coliforms in an inoculum and the time required for an electrical impedance ratio signal to be detected. Pure culture inocula consisting of 100 fecal coliforms in log phase or stationary phase were detected in 6.5 and 7.7 h, respectively. Standard curves of log10 fecal coliforms in wastewater inocula versus detection time, based on samples collected at a sewage treatment plant over a 4-month period, were found to vary from one another with time. Nevertheless, detection times were rapid and ranged from 5.8 to 7.9 h for 200 fecal coliforms to 8.7 to 11.4 h for 1 fecal coliform. Variations in detection times for a given number of fecal coliforms were also found among sewage treatment plants. A strategy is proposed which takes these variations into account and allows for rapid, automated enumeration of fecal coliforms in wastewater by the electrical impedance ratio technique.     

Automated electrical impedance technique for rapid enumeration of fecal coliforms in effluents from sewage treatment plants.

Fecal coliforms growing in a selective lactose-based broth medium at 44.5 degrees C generate a change in the electrical impedance of the culture relative to a sterile control when populations reach 10(6) to 10(7) per ml. The ratio of these changes was measured automatically, and the data were processed by computer. A linear relation was found between the log10 of the number of fecal coliforms in an inoculum and the time required for an electrical impedance ratio signal to be detected. Pure culture inocula consisting of 100 fecal coliforms in log phase or stationary phase were detected in 6.5 and 7.7 h, respectively. Standard curves of log10 fecal coliforms in wastewater inocula versus detection time, based on samples collected at a sewage treatment plant over a 4-month period, were found to vary from one another with time. Nevertheless, detection times were rapid and ranged from 5.8 to 7.9 h for 200 fecal coliforms to 8.7 to 11.4 h for 1 fecal coliform. Variations in detection times for a given number of fecal coliforms were also found among sewage treatment plants. A strategy is proposed which takes these variations into account and allows for rapid, automated enumeration of fecal coliforms in wastewater by the electrical impedance ratio technique.     

Modification of delayed-incubation procedure for detection of fecal coliforms in water.

Three holding media, including the vitamin-free Casitone holding medium (m-VFC) recommended by Standard Methods for the Examination of Water and Wastewater for use with the delayed-incubation membrane filter procedure, were compared for their ability to maintain viability of fecal coliforms. Each medium was tested according to the procedure described in the above reference with 60 to 80 pure cultures of fecal coliforms and a variety of natural water samples containing fecal coliforms. Fecal coliform recovery with m-ST holding medium (containing ethanol, sulfanilamide, and Tris [pH 8.6] was significantly greater than recovery with m-VFC (containing vitamin-free casein hydrolysate, sodium benzoate, sulfanilamide, and ethanol). Recovery with m-VFC, was, in turn, significantly greater than with NSB medium (containing nutrient broth, boric acid, and NaCl as major ingredients). Fecal coliform counts obtained with m-ST by the delayed-incubation membrane filter procedure were higher than counts obtained by the standard immediate incubation. This result suggested that some of the sublethally injured fecal coliforms in natural water samples may have recovered during the incubation period. We propose that m-ST be used in place of m-VFC for the delayed-incubation membrane filter procedure.     

Modification of delayed-incubation procedure for detection of fecal coliforms in water

Three holding media, including the vitamin-free Casitone holding medium (m-VFC) recommended by Standard Methods for the Examination of Water and Wastewater for use with the delayed-incubation membrane filter procedure, were compared for their ability to maintain viability of fecal coliforms. Each medium was tested according to the procedure described in the above reference with 60 to 80 pure cultures of fecal coliforms and a variety of natural water samples containing fecal coliforms. Fecal coliform recovery with m-ST holding medium (containing ethanol, sulfanilamide, and Tris [pH 8.6] was significantly greater than recovery with m-VFC (containing vitamin-free casein hydrolysate, sodium benzoate, sulfanilamide, and ethanol). Recovery with m-VFC, was, in turn, significantly greater than with NSB medium (containing nutrient broth, boric acid, and NaCl as major ingredients). Fecal coliform counts obtained with m-ST by the delayed-incubation membrane filter procedure were higher than counts obtained by the standard immediate incubation. This result suggested that some of the sublethally injured fecal coliforms in natural water samples may have recovered during the incubation period. We propose that m-ST be used in place of m-VFC for the delayed-incubation membrane filter procedure.     

Breeding biology of rooks (Corvus frugilegus L.) in Hawke's Bay,New Zealand

Abstract

Three rookeries in Hawke's Bay were studied during 1966–68. First or replacement clutches were started between 26 August and 23 October. First clutches averaged 4.3 eggs and replacements 3.7 eggs. The mean size of first clutches varied between years from 4.1 to 4.6 eggs. Incubation took 17–18 days. Most losses occurred around hatching, when about 40% of the eggs or young were lost. Incubated eggs and small nestlings incurred losses of 20% and 10% respectively, and all nestlings older than 10 days survived to at least 20 days. On average, 1.4 young were reared per nest in which eggs were laid; successful nests averaged 2.2 young. First clutches averaged 1.3 young (2.4 per successful first clutch). During the season, mean clutch size declined from 4.2 to 3.5, the mean number of young hatched declined from 2.0 to 0.6 per clutch, and the mean number of young fledged from all clutches declined from 1.3 to 0.4 per clutch. Mean nestling weight increased with age from 14 g on the first day after hatching to 360 g on the 19th day. The causes of egg and nestling mortality and the adaptiveness of clutch size are discussed.     

The morphogenesis of Ascaris suum to the infective third-stage larvae within the egg.

Studies of the morphology of Ascaris suum larvae developing in the egg during embryonation in vitro at room temperature showed that 2 molts take place within the egg. The first larval stage (L1) appeared in the egg after 17-22 days of cultivation, the first molt to the second larval stage (L2) took place from day 22 to day 27, and the second molt to the third larval stage (L3) started on day 27 and continued during the 60-day observation period. Infectivity of the eggs was studied by oral egg inoculation in mice and showed that the L3 are the infective stage for mice. Molting to the L3 stage occurs gradually over a period of 2-6 wk, and it is recommended to have an additional maturation period so the infectivity of an egg batch may reach maximum level.