Hydrogen radicals, nitrogen radicals, and the production of O3 in the upper troposphere

The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected.     

两种人工栽培藏茵陈生物学特性的研究

通过椭圆叶花猫(Halenia elliptica D.Don)、四数獐牙菜(Swertia tetraptera maxim)的人工栽培试验表明:两种藏茵陈植物都为两年生草本,第一年仅以叶簇形态生枝条不伸长,只进行营养生长,生长第二年枝条才开始伸长,开花结实后完成生活史;两种藏茵陈播种时间都以秋播为宜,有利于自然通过低温春化作用打破种子休眠,促进翌年春天种子萌发,显著提高田间出苗率;两种藏茵陈通过人工栽培,其茎、叶都比野生植物生长高大、粗壮,可大幅提高生药产量,是保护珍稀野生植物资源的有效途径之一;两种藏茵陈50%以上的种子在土壤中有较长期的休眠特性,一般在一年中的春秋两季萌发,所以适当增加播种量第二年后可使田间一年、二年生植株同时生长,对生药生产可连年持续收获产品,免去了对土壤的耕、翻、耙、种等作业,从而可有效降低栽培成本。     

2株广西鹅源基因XII型新城疫病毒的病原学分析

【目的】深入了解2株广西鹅源基因XII型新城疫病毒(NDV)的病原学特征,为NDV流行分布的系统监测和新城疫(ND)的科学防控提供参考依据。【方法】对2株广西鹅源基因XII型NDV(Goose/China/GX02/2018和Goose/China/GX17/2018)进行病毒噬斑纯化,通过致死鸡胚平均死亡时间(MDT)和脑内接种致病指数(ICPI)试验确定其致病性,分析F蛋白和HN蛋白氨基酸序列与参考毒株的差异位点,并基于F基因全长进行遗传进化分析。【结果】经过DF-1细胞4个代次噬斑纯化可获得2株分离株的纯化株,对应的MDT分别为54和48 h,ICPI均为1.65。2株分离株的基因组长度均为15192 nt,其3’端引导序列为55 nt,5’端尾随序列为114 nt;基于F基因核苷酸序列相似性构建的基因XII型NDV系统发育进化树显示,2株分离株(Goose/China/GX02/2018和Goose/China/GX17/2018)均属于基因XIIb亚型,与我国广东分离株属于同一基因亚型,且我国2010年的分离株、2011年的分离株及2017年后的分离株分别形成3个小分支。2株...     

Equine bronchoalveolar lavage cytology: survey of Thoroughbred racehorses in training

SUMMARY Sixty-two Thoroughbred horses aged between 1 and 7 years in training in Sydney had bronchoalveolar lavage (BAL) samples collected for cytological examination. All horses, except the yearlings and those with a cough, had raced at the time of the examination and the trainers reported satisfactory performance. Free erythrocytes were found In 73% of samples and haemoslderophages In 90% of the samples, Indicating Immediate or past occurrences of exercise-Induced pulmonary haemorrhage (EIPH). Bronchoalveolar fluid from the yearlings contained significantly less (P / 0.05) erythrocytes and haemosiderophages than samples from horses In other age groups. In the older horses, there was also more haemosiderln within the macrophages. No differences In BAL cytology could be attributed to gender, and there was no relationship between BAL cytology and racing performance. The main cytological findings were (mean ± sd): total nucleated cells - 832 ± 578/μL with the main cell types being: macrophages - 59 ± 10% (haemosiderophages - 20 ± 24%); neutrophlls - 9 ± 6%; lymphocytes - 31 ± 9%. The erythrocyte count was 10.3 ± 17.7% of the total cell count. Horses with chronic coughing had a higher proportion of macrophages and a lower proportion of lymphocytes in the leucocytes obtained from BAL. There was a higher occurrence of EIPH detected In BAL findings than that previously reported when endoscopic examination has been used to diagnose EIPH. The occurrence and severity of EIPH as Indicated by the BAL findings was found to be related to exercise Intensity. The cytological findings were similar to those reported in horses in the northern hemisphere. We conclude that BAL cytology may be useful In the diagnosis of various lower respiratory tract disorders and that exercise-induced pulmonary haemorrhage occurs In virtually all horses In race training.     

Responses in milk production to the control of gastrointestinal nematode and paramphistome parasites in dairy cattle

Objective To determine the effect of treating naturally acquired gastrointestinal nematode and paramphistome infections on milk production in dairy cattle.
Design A field trial.
Animals One thousand two hundred and thirty nine dairy cows.
Procedure Cows were either not treated or treated with 4.5 mg/kg oxfendazole, 16.6 mg/kg oxyclozanide or 4.5 mg/kg oxfendazole and 16.6 mg/kg oxyclozanide in March, May and August.
Results A significant increase in milk production, averaging 0.4 L (SE 0.2) per day, was seen when dairy cows infected with gastrointestinal nematodes and paramphistomes were treated with oxfendazole or oxfendazole and oxyclozanide in March, May and August. Cows treated with oxyclozanide alone at these times produced no more milk than untreated cows.
Faecal egg counts confirmed that oxyclozanide treatment reduced paramphistome populations and oxfendazole treatment reduced nematode populations in cows over the 7-month monitoring period.
Conclusion When dairy cows infested with gastrointestinal nematodes and paramphistomes were treated with oxfendazole alone or oxfendazole and oxyclozanide in March, May and August milk production increased.     

Research Progress on Bacillus amyloliquefaciens in Animal Breeding Industry

Bacillus amyloliquefaciens is a kind of non-pathogenic bacteria and widely exists in the environment.During the metabolic process,Bacillus amyloliquefaciens can produce bioactive substances which highly inhibit the activation of multiple pathogens and fungus.In recent years,some bioactive substances are isolated,extracted and purified.With the deeper understanding of Bacillus amyloliquefaciens,it is gradually applied in animal husbandry and aquaculture.This paper summarizes the application and action mechanism of Bacillus amyloliquefaciens in animal breeding industry,it is expected to provide information for further exploration and application.     

The large‐scale capture of eastern grey kangaroos (Macropus giganteus) and red kangaroos (Osphranter rufus) and its application to a population management project

Objective: A large‐scale capture method was developed to enable sterilisation of a macropod population in western Sydney from 2005 to 2018. Methods: Until March 2007, free ranging eastern grey kangaroos and red kangaroos were herded into purpose‐built 15 m diameter capture yards (CYs) for darting with a projectile syringe. From March 2007 onwards, animals were free‐range darted in large areas without herding. Kangaroos were darted with 1.33–5.10 mg/kg tiletamine/zolazepam and 0.01–0.02 mg/kg medetomidine, ± 0.03 mg/kg acepromazine. Deaths were monitored. Population counts were performed annually. Results: There were 5825 capture events involving 3963 kangaroos. Over 85% of all captures occurred from 2005 to 2008. Of all reported deaths (n = 523), 135 were attributed to ill health. Musculoskeletal injuries incurred during capture were the main project‐related cause of death (n = 116). Post capture myopathy was uncommonly diagnosed following capture (n = 19). Conclusion: The herding and capture method enabled a large number of kangaroos to be mobilised and captured with low mortality rates, and the use of CYs resulted in fewer capture‐related injuries and deaths than free‐range capture. The drug doses and combinations used for darting were safe and effective, and the capture technique was successfully applied to a population management project.     

巴林右旗干草原主要牧草的营养成分季节动态与饱和链烷烃组成结构的研究

通过测定10种牧草5月至翌年1月的7种常规营养成分含量及其中8种牧草7和10月的8种饱和链烷烃浓度,对巴林右旗典型干草原的主要牧草的营养成分季节变化规律和同一季节饱和链烷烃组成差异进行了研究。结果表明,多数草样的粗蛋白含量5月到翌年1月逐季显著降低(P<0.05),Ca含量10月最高(P<0.01),总磷(TP)含量5月最高(P<0.01),中性洗涤纤维与酸性洗涤纤维含量极显著正相关(P<0.01),Ca与TP含量极显著负相关(P<0.01);7、10月,多数草样的C₂₉、C₃₁饱和链烷烃浓度极显著(P<0.01)高于其余的6种饱和链烷烃,其饱和链烷烃组成结构的主成分值Z₁、Z₂的差异显著(P<0.05)。上述研究表明,巴林右旗干草原的主要牧草的蛋白质逐季减少且钙磷含量彼此反向变化,需对家畜及时补饲,其饱和链烷烃组成差异明显,通过链烷烃技术估测放牧家畜采食结构可行。