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1.
在起垄种草苹果园中,将果园牧草刈割后覆盖在垄上,研究牧草覆盖后对垄沟0~60 cm土壤中水分含量、微生物数量、土壤酶活性及土壤肥力的影响。结果表明,与未覆盖牧草相比,垄上覆盖牧草后,垄沟中土壤水分含量提高,土壤微生物总数、细菌、真菌和放线菌数量增加,土壤脲酶、蔗糖酶和过氧化氢酶活性增加,土壤有机质、全N、全P、全K、速效N、速效P、速效K也均有不同程度的增加。而这种差异以浅层土壤较明显,覆盖牧草后显著改善了垄沟0~40 cm的土壤特性(P < 0.05),对40~60 cm土壤无显著影响。说明果园刈割牧草可作为一种较好的覆盖材料,将其覆盖垄上可改善垄沟中土壤特性、提高土壤含水量和肥力,是果园牧草的一种有效利用方式。  相似文献   

2.
3.
为提高实蝇粘虫板对桔小实蝇的诱杀效果,减少对天敌的诱杀,为科学悬挂实蝇粘虫板提供参考依据。采用4种悬挂方式,分别为悬挂于树冠中部胶面与地面垂直、悬挂于树冠中下部胶面朝下、悬挂于树冠中下部胶面朝上、悬挂于树冠上部胶面朝上,调查实蝇粘虫板上桔小实蝇、其它害虫和天敌的种类和数量。结果表明,4种悬挂处理的实蝇粘虫板共诱杀到20个昆虫种或类群,其中悬挂于树冠中部胶面与地面垂直的实蝇粘虫板诱杀昆虫种类、多样性指数最高,而悬挂于树冠中下部胶面朝上的实蝇粘虫板的益害比最高;悬挂于树冠中部胶面与地面垂直、树冠中下部胶面朝下的实蝇粘虫板对桔小实蝇的诱杀数量显著高于其它2种悬挂方式的实蝇粘虫板(p<0.05);悬挂于树冠中下部胶面朝上和树冠上部胶面朝上的实蝇粘虫板均对食蚜蝇具有较强的诱杀作用。因此,采用树冠中部胶面与地面垂直、树冠中下部胶面朝下的悬挂方式均可以作为田间应用实蝇粘虫板的方法;但采用树冠中下部与地面平行朝下的悬挂方式更有利于天敌的保护。  相似文献   

4.
This review article presents immunological issues in the course of the turkey rhinotracheitis (TRT) emphasizing local immunity mechanisms, both humoral and cell-mediated, in the upper respiratory system. Studies on the influence of the humoral immunity in the course of infection and vaccinations against TRT have revealed many times the absence of correlation between the titre of specific IgY anti-aMPV (avian Metapneumovirus) antibodies in the serum and in the upper respiratory washings and the immunity against the occurrence of the clinical form of the TRT. Considering the above, T cells are increasingly often regarded as the main factor involved in the upper respiratory immunity against the TRT. However, there have been just a few reports on the role of the T cells in the local immunity processes in the infection with aMPV in turkeys. Additionally, studies of the T-cell-associated immunity against the TRT have given ambiguous results. Immunoprophylaxis issues against the aMPV infections are a significant part of the work where the authors confront current vaccination programmes against the perspectives of use of the future vaccines against the TRT. Future vaccines should face the following criteria: absence of the risk of immunosuppressive effect and reversion of vaccine strains virulence, ease-of-use combined with the possibility of administration of the vaccine to the large numbers of turkeys. The leading role in future vaccination programs for birds against the TRT is likely to be played by the in ovo technique and the recombinant vaccines. Great hopes are also linked with the development of subunit vaccines against the aMPV.  相似文献   

5.
In the small intestine mucosa of 24 gnotobiotical piglets experimentally infected the first day post partum with oocysts of the coccidium Isospora suis, the activities of dipeptidylpeptidase IV (EC.3.4.14.5.; DAP IV) and gamma-glutamyl transferase (EC.2.3.2.2.; GGT) in the microvillous zone of enterocytes were evaluated by scanning densitometry. The tissue of the small intestine in piglets infected with a dose of 100,000 oocysts of the coccidia of I. suis was examined in the period from the first till the eleventh day post infection (DPI). In the control piglets at the age of 2-5 days it was found that most of the DAP IV activity was located in the microvillous zone of the enterocytes of the middle jejunum, rear jejunum and ileum. The DAP IV activity of duodenum mucosa was lower; as compared with the activity in the mucosa of the jejunum and ileum it reached 53-57%. In the case of GGT activity, the highest density values of the reaction product were recorded in the microvillous zone of enterocytes of the duodenum and the whole jejunum, the lowest in the ileum mucosa (86-89%) of the activity found in the duodenum and jejunum). During the experimental infection the infected piglets had a significant deficit of both peptidases, especially DAP IV (the whole studied period). The development of GGT activity was slightly different with the onset of the marked decline of the enzyme activity only on the fifth DPI. The lower GGT activity persisted till the eighth DPI. The density of the GGT reaction product began to return to the normal on the ninth to eleventh DPI. No predisposition in the location of the deficit was observed in the peptidases studied during the infection. The decline of the activity of both enzymes influenced also the mucosa of all studied parts of the small intenstine. The difference lay in the relevance of lowering of the density of reaction product of DAP IV and GGT on other DPI and in the different intensities of the return of the activity to the physiological normal.  相似文献   

6.
随着养鸡生产规模的扩大、养殖密度的增加,鸡球虫病成为危害养鸡业发展的最严重的疾病之一。本文试从鸡球虫病的流行特点、危害性、患病鸡的症状与诊断及球虫病的防制措施等方面对球虫病的防制作初步探讨。  相似文献   

7.
The function of several intrinsic muscles of the fore-and hind limbs of 5 ponies walking normally was evaluated via surface electromyography. Electromyographic signals were band-pass filtered, rectified, linear enveloped, and standardized to the stride duration. Mean data from the muscles of the left and right limbs that were obtained from at least 30 strides in 2 recording sessions were recorded as electromyographic signals-time curves. The timing of muscle activity was determined from these graphs. On the basis of the major peaks in the electromyographic signal, muscle functions were identified. In the forelimb, the extensor carpi radialis muscle was involved in extension of the carpus at the end of the swing phase of the stride, and it provided support to flexion of the cubital joint at the beginning of the swing phase. The common digital extensor muscle extended the distal joints of the forelimb at the end of the swing phase. The ulnaris lateralis muscle provided support to extension of the cubital joint at the beginning of the stance phase, and the flexor carpi radialis muscle flexed the carpus at the beginning of the swing phase. The flexor carpi ulnaris muscle extended the cubital joint at the end of the swing phase. In the hind limb, the long digital extensor muscle flexed the tarsus at the beginning of the swing phase and extended the digital joints preceding the stance phase. The deep digital flexor muscle prevented overextension of the distal interphalangeal joint during the stance phase and flexion of the digital joints during the swing phase.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
豪猪雌性生殖器官的解剖研究   总被引:4,自引:4,他引:0  
为了解雌性豪猪的生殖生理,为其发情鉴定、催情技术、人工授精、胚胎移植、体外受精等人工繁殖技术方面的研究提供基础依据,对成年雌性豪猪的生殖器官进行了系统解剖研究。结果表明,雌性豪猪的性腺没有明显的季节性变化,但是在发情周期的不同时期卵巢有不同的变化,当母豪猪发情后,卵巢表面有成熟的卵泡,使整个卵巢体积增大,发情期过后,则卵巢相对缩小。其它生殖器官也都具有各自的解剖特征。  相似文献   

9.
Explants from the matrix of the stratum medium of the wall of the equine and bovine hoof each were cultured on a microporous membrane, using a standard culture medium. After incubation at 37 C, the outgrowth was a mixture of keratinocytes and fibroblasts, with predominance of the latter. After incubation at 34 C, the keratinocytes dominated, covering the lateral surfaces of the explant as well as the basal surface. Lateral outgrowth of keratinocytes was observed at the borderline of the original epidermis and at the borderline of the explant's contact with the membrane. Epithelial outgrowth from the former consisted of rounded aggregates protruding into the medium, whereas outgrowth from the latter formed a pluristratified carpet occupying a considerable part of the membrane. In the outer layers, keratinocytes covering the cut surfaces of the dermis of the explant had a differentiation pattern of the kind that characterizes the keratinocytes of the hoof; differentiation was not observed in the lateral outgrowth.  相似文献   

10.
The area of skin supplied by the afferent fibers in a peripheral nerve is called the cutaneous area (CA) of that nerve. The CA responsive to movement of wool or hair in the genital regions were mapped in 17 ewes, with the identifications of the peripheral nerves and of the spinal nerves contributing to the pudendal plexus being checked at necropsy. Differences were found in the origins and extent of CA of the cutaneous branches from the sacral plexus. The CA of the caudal rectal nerves and of a nerve that passed caudally between the caudal vertebrae and the ventral sacrococcygeus muscle lay lateral to the anus and in the adjacent skin of the tail. The CA of the proximal cutaneous branch and of the distal cutaneous branch from the pudendal nerve (or plexus) overlapped craniocaudally (by approx one-half) the CA of the distal cutaneous branch extending ventrally and ending just caudal to the ipsilateral mammary gland. The deep perineal nerve innervated the skin immediately lateral to the anus and vulva. The dorsal nerve of the clitoris innervated hairs on the ipsilateral half of the vulva. Other fibers in the pudendal nerve were presumed to pass into the mammary branch of the nerve. They innervated the skin ventral to the vulva, the ipsilateral mammary gland, and (in some ewes) areas of the skin cranial to the mammary gland. The CA of the genitofemoral nerve included the ipsilateral teat and the inguinal fossa.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
The precise location of neurovascular structures within the relatively long mandibular canal of the horse is of paramount importance in surgical procedures of the area. The inferior alveolar nerve (IAN) enters the mandibular canal on the medial (lingual) surface of the mandible and innervates all the mandibular teeth. During its course, the nerve moves laterally, crossing the roots of the inferior cheek teeth. However, the exact anatomical relationships occurring between the IAN and the roots of the equine mandibular cheek teeth have not been described in detail. In this study, the mandibles of 40 horses were examined with CT scans and then used for bilateral detailed anatomical dissection, to assess the path of the IAN and its relationship to the roots of the lower cheek teeth. The data obtained show that the equine IAN is located ventral to the apices of the molar teeth (311/411, 310/410, 309/409 according to the Triadan numerical system). At the level of PM4 (308/408), the IAN is located on the lingual side of the roots and coronally to its apices. At the level of PM3 (307/407), the IAN is then found on the lingual side of the roots but in proximity to the apices. In 2 of 40 horses (=5%), the IAN moves towards the lingual side between the mesial and the distal root of PM4. Our observations are valuable for planning a surgical approach to the ventral side of the mandible in the horse and to avoid potential post‐operative complications.  相似文献   

12.
Considerations on the kinematics of the pelvic limbs of the horse Some joint diagrams change their trigonometric value; this occurs in different ways depending on the type of joint and on the forces acting on the joint during the walk and trot. The morphological specialities of the hip, stifle, hock and fetlock joints are compared to the special morphology of the joint types and to the change of movement in the vertical and horizontal planes during the walk and trot. An attempt is made to relate the changes in the trigonometric value of the excursion of the limb to the structural peculiarities of the joints and to the chronaxy differences of the flexor and extensor muscles.  相似文献   

13.
The purpose of this investigation was to determine the central distribution of the efferent neurons of the recurrent laryngeal nerve (RLN) in the sheep by the use of the retrograde transport of the fluorescent tracer Fast Blue. The distribution of the RLN neurons was also compared with that of the neurons simultaneously labelled by injection of another tracer, Diamidino Yellow dihydrochloride, into the cervical trunk of the vagus nerve (CTV). Injections of the tracer into the CTV resulted in heavy retrograde labelling of neurons in the ipsilateral dorsal motor nucleus of the vagus nerve, in the nucleus ambiguus, in the nucleus retroambigualis and in the reticular formation surrounding the nucleus ambiguus. Following injections of the tracer into the RLN, labelling of neurons was seen over a wide area of the ipsilateral nucleus ambiguus and in the nucleus retroambigualis. Species differences in the distribution of the efferent component of the RLN are discussed, in particular ruminants compared to nonruminants.  相似文献   

14.
Detailed studies on the distribution of the muscle coat at the omasoabomasal junction in cattle, especially in the pila omasi, were carried out in order to clarify the mechanism of closing of the ostium omasoabomasicum. Anatomical and histological observations revealed that the muscle coat forming the circumference of the ostium omasoabomasicum is composed of inner circular and outer longitudinal layers. The former was particularly thickened at the end of the sulcus omasi (pila omasi). Joined to the pila omasi was a thick muscle bundle which extended from the labium sinistrum (left lip) of the sulcus reticuli and ran obliquely along the floor of the sulcus omasi. Moreover, on the abomasal side of the ostium omasoabomasicum, vela abomasi were formed in such a manner as to surround the ostium omasoabomasicum. These were continuous with the edges of the sulcus omasi. Judging from its location and muscular structure, the pila omasi may contract in accordance with the contraction of the reticulum. As a result, the ostium omasoabomasicum may be narrowed and the vela abomasi pulled toward the omasum, perhaps obstructing the ostium omasoabomasicum. Accordingly, it is presumed that the retention of contents in the omasum may effectively prevent abomasal contents from moving backward into the omasum.  相似文献   

15.
安康库区现代生态渔业的历史与发展现状   总被引:1,自引:0,他引:1  
为探索集约养殖与水域生态保护的关系,文章历史地分析了安康现代生态渔业的发展进程,对安康“宜渔则鱼、以鱼净水”发展生态渔业的指导思想和“面控规模、点调结构”的技术措施进行了思考,提出了发展现代生态渔业集约养殖是基础、根本出路在科技、发展动力在政策的观点.文章认为,安康传承鱼鲜纳贡历史,以集约养殖方式发展现代生态渔业,产量产值跃居陕西之首,汉江安康段水体保持了饮用水质量,是集约养殖时空可控特点的鲜活运用,对发展现代生态渔业有重要参考价值.  相似文献   

16.
黔草1号高羊茅种子的千粒重对发芽成苗的影响   总被引:4,自引:0,他引:4  
用黔草1号高羊茅种子为试验材料,研究其不同千粒重对发芽率、出苗率、出苗速度和成苗率的影响。研究结果表明:千粒重越大,其发芽率、出苗率、成苗率越高,出苗速度越快,成苗素质越好,同时,种子的发芽率与出苗率、发芽率与成苗率以及出苗率与成苗率之间存在极为密切的正相关关系。  相似文献   

17.
小说的“多声部现象”主要从两个方面来展现,一方面在故事情节的主题上,小说充满了复调色彩;另一方面在小说的章节安排上,呈现出奏鸣曲式的文本结构。在小说《情人》中,围绕“爱”这一主题而产生的变奏,是衍生出“情人”这一身份的基础;在语言上,用小调的特征来体现小说的语言表达方式,是呈现小说音乐结构的必要手段。  相似文献   

18.
用乳胶加洋红颜料对32例初生仔猪的腹主动脉进行灌注,然后测量其小肠、大肠的长度、口径以及动脉分枝数目,利用微机处理得出,小肠的一级分枝与终末分枝、小肠长度与一级分枝、小肠长度与终未分枝有相关性,但小肠直径与动脉分枝无相关性。大肠的长度与终末枝、大肠的直径与终未枝有相关性。  相似文献   

19.
Casts of the nasolacrimal duct system were obtained from 50 euthanised cats including brachy-, meso- and dolichocephalic breeds. The course of the nasolacrimal duct, which was assessed radiographically and gross-anatomically, was strongly related to the shape of the skull. In meso- and dolichocephalic cats the nasolacrimal duct formed a dorsally opened arch with the descending part being directed rostroventrally. The main part of the duct passed the nasal cavity in a rather horizontal course parallel to the hard palate and was located ventrally to the lacrimal foramen. However, foreshortening of the face was associated with a right-angled or even acute-angled alignment of the duct. In higher degrees of brachycephaly the main part of the duct ascended beyond the level of the lacrimal foramen and passed the nasal cavity dorsal to the level of the lacrimal foramen. This specific course of the nasolacrimal duct in brachycephalic cats was consistent with a steeper alignment and attachment of the maxilloturbinate. Accessory orifices of the nasolacrimal duct opening into the nasal cavity had never been observed. The present results strongly suggest that the specific course of the nasolacrimal duct in brachycephalic cats might hinder the drainage of the lacrimal fluid irrespective of the diameter of the lumen of the nasolacrimal duct system.  相似文献   

20.
This work was carried out on the scleral shelf of the eyeball of the donkey, cow, buffalo, camel, sheep, goat, pig and dog. The results of this work shows that the length of the shelf varies in different regions in all studied animals. The dorsal shelf is the longest followed by ventral one, the lateral shelf is the smallest followed by the medial one. The camel has the longest dorsal and ventral shelf followed by donkey, while the buffalo and cow have the smallest ones among the large animals. Among the studied small animals, the dog has the smallest dorsal and ventral shelf followed by pig. However, the small ruminants have the longest ones. On the other hand, the medial and lateral shelves are longest in donkey and smallest in camel. The dog and the small ruminants have the longest medial and lateral shelf of the studied small animals. The camel has the highest value of dorsal and ventral shelf and lowest value in the medial and lateral ones. Therefore the outline of the outer surface of the cornea is highly oval, the reverse results were observed in donkey; in which the cornea has highest degree of circularity followed by cow and buffalo.  相似文献   

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