动物学野外实习教学改革与实践

随着高校竞争的加强,长江师范学院定位于由过去教学科研型转向教学应用型大学,传统的动物学野外实习模式已经不能适应新形势下的教学要求,为了取得令人满意的野外实习效果,基于作者自身的教学实践,对长江师范学院动物学野外实习地点、教学方式、教学内容以及考核方式的改革进行了探讨,以期为其他高校的动物学野外实习教学提供借鉴和参考。     

贵州足球场草坪主要病虫害发生及防治

1998～ 1999年对贵州省足球场草坪病虫害进行了调查研究 ,其主要病虫害有 :锈病、禾草云斑病、褐斑病、禾生腐霉病、粘虫 ,麦二叉蚜等。并阐述了病虫害发生规律及防治技术 ,旨在为足球场草坪病虫害的防治提供参考     

Intermittent Stress in Pigs: Behavioural and Pituitary-Adrenocortical Reactivity

Abstract

Ninetysix pigs, half females and half castrated males from 12 litters, were housed in 24 groups of 4 litter mates (2 females, 2 castrates). The pigs were weaned at 4 weeks of age and from the age of 115 days half of the groups were subjected to a schedule of unpredictable, inescapable electroshocks for 33 days, and half served as control. The adrenocortical reactivity to ACTH stimulation and to an emotional stressor (the procedure associated with initiation of blood collection) was measured in females, whereas the behavioural and pituitary-adrenocortical reactivity to an open field test was measured in castrates, as was the behavioural reactivity in a social test. Intermittent stress increased adrenocortical reactivity to ACTH stimulation significantly. This effect was present within the first week of intermittent stress (p < 0.06), but no difference was found after 4–5 weeks of stress. In contrast, the adrenocortical reactivity to additional emotional stressors was unaffected by stress after one week of intermittent stress, but increased after 4–5 weeks. In the open field test, centre location increased after one week of intermittent stress, whereas exploration decreased and walking and ambulation increased after 4–5 weeks of stress. In addition, 4–5 weeks of intermittent stress decreased aggressiveness in a social test. In conclusion, the change in reactivity to an additional acute stressor during intermittent stress appeared in different variables and contexts at different times during the course of intermittent stress. Thus, assessment of stress based on changed reactivity has to include several distinct measures of behavioural and hormonal reactivity.     

Genetic diversity,anti‐microbial resistance,plasmid profile and frequency of the Vi antigen in Salmonella Dublin strains isolated in Brazil

Salmonella Dublin is strongly adapted to cattle causing enteritis and/or systemic disease with high rates of mortality. However, it can be sporadically isolated from humans, usually causing serious disease, especially in patients with underlying chronic diseases. The aim of this study was to molecularly type S. Dublin strains isolated from humans and animals in Brazil to verify the diversity of these strains as well as to ascertain possible differences between strains isolated from humans and animals. Moreover, the presence of the capsular antigen Vi and the plasmid profile was characterized in addition to the anti‐microbial resistance against 15 drugs. For this reason, 113 S. Dublin strains isolated between 1983 and 2016 from humans (83) and animals (30) in Brazil were typed by PFGE and MLVA. The presence of the capsular antigen Vi was verified by PCR, and the phenotypic expression of the capsular antigen was determined serologically. Also, a plasmid analysis for each strain was carried out. The strains studied were divided into 35 different PFGE types and 89 MLVA‐types with a similarity of ≥80% and ≥17.5%, respectively. The plasmid sizes found ranged from 2 to >150 kb and none of the strains studied presented the capsular antigen Vi. Resistance or intermediate resistance was found in 23 strains (20.3%) that were resistant to ampicillin, ciprofloxacin, chloramphenicol, imipenem, nalidixic acid, piperacillin, streptomycin and/or tetracycline. The majority of the S. Dublin strains studied and isolated over a 33‐year period may descend from a common subtype that has been contaminating humans and animals in Brazil and able to cause invasive disease even in the absence of the capsular antigen. The higher diversity of resistance phenotypes in human isolates, as compared with animal strains, may be a reflection of the different anti‐microbial treatments used to control S. Dublin infections in humans in Brazil.     

青海足球场地病虫害防治

青海省足球场草坪所选用的草种基本上是冷季型草坪草种,如高羊茅、紫羊茅、黑麦草等均从国外引进.近年来病虫害较为严重,2003-2004年对其进行了调查研究,为足球场草坪病虫害的防治提供依据.     

Analysis of the toxic potential of Palicourea corymbifera (Müll. Arg.) Standl. in laboratory animals

Palicourea species may produce bovine toxicity. Palicourea corymbifera grows in terra firme forests within the Amazon rain forest and in Tropical America, particularly in spots that gave place to gazing areas. The lyophilized extract done with the aerial organs of P. corymbifera were analyzed in male and female mice. Results revealed a significant toxicity: LD50 was 1.10 (1.04-1.15)g/kg for male mice, and 1.05 (1.00-1.10)g/kg for female mice. Locomotion was affected as well as there were reflexes linked to environmental stimuli in addition to changes in posture. Progressive central nervous system stimulus signs such as trembling and convulsions were detected, the latter followed by the animal's death. Macroscopic histopathological exams performed on the liver, kidneys and lungs of mice submitted to necropsy did not indicate the existence of lesions. General activity of animals, measured in an open field, was reduced as a result of the administration of the extract. Duration of locomotion and rearing frequency were reduced, in opposition to an increase in the duration of immobility. Thin layer chromatography analysis showed that monofluoroacetic acid is present in the lyophilized extract, but other qualitative techniques as gas chromatography/mass spectrometry and 19F nuclear magnetic resonance showed that the MFAA was not present in the extract, and that the toxicity is related to other compound, although the toxic profile is very similar to that of MFAA. P. corymbifera was shown to be significantly toxic to laboratory animals and investigation of the possible toxic substance shall be done.     

建立密植高产桑园的桑压条苗甲醛处理法

为了改造低产桑园、建立密植高产桑园,研究建立了提高压条苗生产效率的压条苗甲醛处理法,研究结果表明压条苗甲醛处理的生根数比环割处理增加130%,比非环割增加190%;压条苗甲醛处理的新根的生长比环割处理高1.5倍,比非环割处理高1.3倍;成苗率也是压条苗甲醛处理最好。该方法是一种高效成苗的方法。     

嘉兴平原桑园土壤分类及肥力的调查

选择浙北嘉兴平原桑园代表性土壤，进行调查，研究其成因、分类及特性，并对高低产桑园土壤的理化性状进行化验分析，明确了嘉兴平原桑园土壤是历史上由人工堆迭而成，在分类系统上归属于潮湿土纲、正常潮湿土亚纲、潮土土类、暗潮土亚类、堆迭土土属，又分为粘质堆迭土、壤质堆迭土、粉质堆迭土３个土种。在统计众多土壤理化性状数据的基础上，暂拟本区高产桑园土壤１６项理化性状，作为本地区桑园地力建设的参考。     

基于玉米种植的生长育肥猪粪污农田承载力

本研究旨在以生长育肥猪和玉米种植农田为模型,准确评定生长育肥猪粪肥养分的产生量和不同施肥量下玉米的生物产量及养分需求量,以此为基础建立基于粪肥还田利用的玉米种植农田粪肥承载系数。试验选取8头13周龄胎次和体重（（33.2±3.5）kg）相近的"杜×长×大"生长育肥猪进行饲养试验,分别于16和25周龄各进行一次消化试验,测定其粪、尿产量及粪肥氮、磷产生量。玉米种植试验设6个处理组,对照组施用化肥,负对照组不施肥,4个试验组分别按玉米种植全期氮标准需要量的100%、130%、160%和磷标准需要量的100%施用猪粪有机肥,分别在乳熟后期和完熟期测定玉米种植的氮、磷需求量,与猪粪肥氮、磷产生量拟合,测算粪肥农田承载系数。结果表明,按130%氮需求量施用猪粪有机肥,一季玉米种植乳熟后期和完熟期收获,对氮、磷的需求量分别为122.1、53.0 kg·hm^-2和190.2、62.8 kg·hm^-2,按130%氮施肥量下乳熟后期和完熟期收获的玉米农田承载系数,以N为基础为61.1头·hm^-2和95.2头·hm^-2,以P为基础为90.5头·hm^-2和107.3头·hm^-2,而且施用猪粪有机肥还可增加玉米生物产量,一定程度上增加玉米中氮、磷含量。因此,分别基于玉米对氮和磷的需求,单季玉米种植每公顷土地生长育肥猪的承载参数分别为95.2头和107.3头。