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81.
为了解肃南地区肉牛口蹄疫免疫动态,达到为本地区肉牛养殖制定科学口蹄疫免疫程序的最终目的。本文与2019年3月份采用随机抽样方法选取120头肉牛,分成了3组,分别采取不同免疫程序,根据免疫抗体检测水平的变化,选择免疫效果最佳的免疫程序。试验结果表明,第3组的口蹄疫A型、O型抗体水平最高。因此,本试验推荐肉牛场每年免疫3~4次O型和Asia I型二价口蹄疫灭活疫苗。  相似文献   
82.
魔芋(Amorphophallus rivieri Durieu)叶面积测定方法的?…   总被引:11,自引:0,他引:11  
以叶面积仪实测的魔芋(Amorphophallus rivieri Durieu)叶面积为参照,分别获得了用叶片上各小裂片的长径(L)与短径(W)计算叶面积的校正值(K1=0.63)和用叶片上3个羽片的长度(D)与羽片的开张度(E)计算叶面积的校正值(K2=0.52);得到了用L和W计算的单株叶面积为0.63∑ni=1LiWi(n为小裂片总数),用D和E计算的单株叶面积为0.52∑i=1DiEi(  相似文献   
83.
In order to identify chromosomes involved in resistance to Fusarium head blight, a set of 21 substitution lines of Triticum macha (resistant) chromosomes into ‘Hobbit’'sib’(susceptible) were evaluated in trials over 2 years. For the first year's trial, all plants were inoculated on the same day with a conidial suspension of F. culmorum. For the second trial, individual plants were inoculated precisely at mid anthesis of each plant over a period of 2 weeks. The disease level was assessed by visual scoring, relative ear weight and F. culmorumn‐specfic quantitative polymerase chain reaction. The results showed that T. macha chromosomes 1B, 4A and 7A conferred good overall resistance, suggesting that they carry important genes for resistance. In two additional trials, T. macha and ‘Hobbit’'sib’ were evaluated for resistance to brown foot rot. The results showed that T. macha was more susceptible than ‘Hobbit’‘sib’, indicating that stem base disease response is not correlated with head blight resistance in these cultivars.  相似文献   
84.
Fusarium graminearum andF. culmorum are capable of infecting winter cereals at all growth stages. From natural field epidemics of wheat head blight and rye foot rot, three fungal populations were collected with 21, 38 and 54 isolates, respectively; their aggressiveness was analyzed in comparison to collections ofF. graminearum (25 isolates) andF. culmorum (70 isolates) that represent a wide range of geographical locations and host species. All isolates were tested for aggressiveness on young plants of winter rye in the greenhouse and scored for disease severity on a 1–9 scale. Disease ratings of individual isolates ranged from 1.5 to 5.7 indicating quantitative variation of aggressiveness. Genotypic variance was highest in the twoFusarium collections. No substantial difference was found in the amount of genotypic variation betweenF. graminearum andF. culmorum. Individual field populations revealed 57–66% of the total genotypic variation of the collections. This implies a high degree of diversity of aggressiveness within single field populations ofF. graminearum andF. culmorum causing natural epidemics.  相似文献   
85.
MAGNETIC RESONANCE IMAGING OF THE EQUINE FOOT   总被引:1,自引:1,他引:0  
The purpose of this study was to assess the ability of magnetic resonance imaging to depict abnormalities of the equine foot. MRI was performed on isolated limbs which had lesions of the foot. These images were made in 3 perpendicular planes (sagittal, transverse and frontal) using a T1 weighted sequence and were 5mm thick. Images accurately depicted normal and pathologic structures in the foot and proved to be very precise for documenting degenerative joint disease, navicular disease and laminitis lesions. This preliminary study demonstrates the considerable potential of MRI in the diagnosis of locomotor problems in the horse.  相似文献   
86.
嗜肺性巴氏杆菌在兽医病原学中的地位并不受重视 ,对动物的致病作用也很少见报道 ,在鸵鸟病中更是罕见。文章针对一起鸵鸟慢性死亡的病例 ,经临床症状、病理剖检和实验室检验 ,诊断为嗜肺性巴氏杆菌所致 ,并提出了相应的有效防治方案  相似文献   
87.
Foot health represents an issue in wild avifauna breeding practices. In particular, prevalence of digital ulceration (DU ) and foot pad dermatitis (FPD ) are valid indicators of welfare in wildlife conservation centres and may be interpreted as to fitness for bird's reintroduction into the wild. This study meant to test the effects of raising practices on foot pad health in captive Sardinian partridges (Alectoris barbara barbara Bonnaterre, 1790) reared for biodiversity conservation, to assess welfare and fitness to reintroduction into nature. A total of 22 couples were allotted into two experimental groups. In one group, 10 couples were housed in 10 cages for breeding partridges, consisting of two animals each, with metal wire flooring system, above trays where droppings were collected. The remaining 12 couples were housed in six aviaries, consisting of four animals each, on natural (earth and stones) ground. In both groups, partridges were fed identical diets. No significant differences of food pad scoring were found between birds housed in cages (2.3 ± 0.4) and those reared in aviaries on natural ground (2.5 ± 0.6). Moreover, scores of male foot pads for both groups (2.4 ± 0.6) had no significant differences in comparison with female foot pads, independently on housing (2.5 ± 0.4). Body mass (BM ) was higher (+4.36%) than average BM reported for wild Sardinian partridges. Digital ulceration was found in the 20% of females, exclusively from the cage group. Body mass of females in cages with metal wire flooring appeared to be significantly (p  < .001) and negatively correlated (r  = ?.528) with DU prevalence. These results suggest that housing conditions impacts differently on behaviour of females and males in one same couple, and this relates to foot health, in particular as to DU prevalence.  相似文献   
88.
89.
The structures of the equine foot have the unique ability to adapt, change shape and restore. There are multiple benefits in shod vs. barefoot or in allowing the horse to be without shoes for a given time period to improve the palmar section of the foot. However, it requires a transition period, a change in the manner in which the foot is trimmed, a commitment from the owner/trainer and, in the case of leaving the horse without shoes permanently, it depends whether the horse can perform the desired function without shoes.  相似文献   
90.
Limited information exists regarding associations between distal interphalangeal joint (DIPJ) abnormalities and synovial invagination changes in the distal sesamoid (navicular) bone. This retrospective, analytical study aimed to measure specific characteristics of the synovial invaginations of the navicular bone to determine whether any single characteristic was associated with abnormalities in the DIPJ or navicular apparatus (NA) using high field MRI and a sample of 200 horses’ feet. The DIPJ and NA were graded independently by three scorers. The grades were averaged, creating a global pathology score for the DIPJ, NA, and synovial invaginations. Higher global scores represented more severe pathology. The number of invaginations, depth of penetration, invagination shape, and cross-sectional area (CSA) of the largest invagination were recorded. Interobserver agreement was measured using Cohen's Kappa. Associations of global scores of the DIPJ and NA with individual invagination characteristics were assessed using linear mixed modeling. A significant relationship was found between the number of invaginations and global DIPJ score, with higher invagination numbers associated with higher DIPJ scores. For invagination depth and CSA, a significant relationship was noted with global scores of both the DIPJ and NA. Reliable relationships between the shape of synovial invaginations and global scores of DIPJ and NA were not found, likely due to poor interobserver scoring (0.305). These findings suggest that primary DIPJ disease and NA pathology should be considered when noticing alterations to navicular synovial invaginations on MRI. This contrasts traditional views that synovial invagination abnormalities are indicative solely of NA pathology.  相似文献   
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