两种普鲁兰类酵母菌株Aureobasidium pullulans对三种核果类褐腐病菌Monilinia laxa,Monilinia fructicola和Monilinia fructigena的生物控制作用

本试验研究了从"Redhaven"桃果肉中分离得到的两种拮抗酵母菌株L1和L8对三种核果类褐腐病原菌(Monilinia laxa,Monilinia fructicola及Monilinia fructigena)的离体和活体拮抗效果。这两种拮抗菌株是经初步验证能够减轻桃和油桃的褐腐病症状后筛选出的,并最终通过分子生物学及形态学手段鉴定为Aureobasidium pullulans(出芽短梗霉菌)。通过活体接种三种褐腐病菌的试验研究发现,两种拮抗菌的高压灭菌悬液及无菌过滤液对果实褐腐病的发生均无抑制作用,而含有L1和L8菌株的菌悬液可完全抑制M.laxa和M.fructicola引起的褐腐病的发生,并使M.fructigena引起的褐腐病发病率分别降低70%和90%。在另一项试验中,将油桃用两种拮抗菌液处理后接种三种褐腐病菌,然后将其在0℃下贮藏21 d,再在20℃下放置7 d。结果表明,低温抑制了褐腐病的发生,处理和对照果实均无褐腐病的症状。但在20℃下放置7 d后,对照果实的褐腐病发病率均超过了45%,而LI和L8处理分别可以将接种M.fructigena病原菌果实褐腐病的发病率降低89.8%和91.2%,说明两种拮抗菌的处理可完全抑制接种M.laxa和M.fructicola引起的果实褐腐病的发生。两种拮抗酵母菌株的最佳抑菌浓度为108CFU.mL-1,L1在107CFU.mL-1浓度时也具有较好的抑菌效果。L8菌株在107CFU.mL-1浓度时对由M.fructigena和M.fructicola引起的果实褐腐病无抑制活性,处理与对照果实无差异。而对于接种了M.laxa的油桃果实,与对照相比,107CFU.mL-1浓度的L8菌株却可显著降低褐腐病的发病率。尽管在0℃和20℃下贮藏的油桃果实伤口处的L1和L8菌的数量增长较慢,但已经足够控制果实褐腐病的发生。综上所述,本项研究确定了可作为开发采后生物杀菌剂活性成分的两种A.pullulans拮抗菌株,并用于抑制引起核果类作物采后严重经济损失的三种Monilinia真菌。     

Freezing of canine semen in an animal-free protein extender

The aims of this study were to study the prevalence of oviduct abnormalities of buffaloes, investigate bacteria accompanying hydrosalpinx, pyosalpinx and salpingitis. In addition, the study was designed to investigate the correlation between bacterial infection of the uterus and oviduct lesions in buffaloes. Bacteriological examinations were performed on hydrosalpinx, pyosalpinx and salpingitis. Hydrosalpinx was found in 28 (6.9%) cases of which 20 (71.4%) were found unilaterally and 8 (28.6%) bilaterally. Pyosalpinx was recorded in 12 (2.9%). Three cases (0.7%) of oviducts filled with blood were recorded. Obstruction of oviducts was recorded in 5 (1.2%). Adhesions between mesosalpinx and perisalpingeal tissues were observed in 7 (1.7) cases. One case of double oviduct was found in the left side of the tract examined. The most prevalent bacteria recovered from hydrosalpinx were Corynebacterium hemolyticum and Actinomyces bovis, 42.8% and 28.6%, respectively. No correlation was noticed between bacteria isolated from the uterus and hydrosalpinx. The most prevalent bacteria recovered from pyosalpinx were Escherichia coli, Archanobacterium pyogenes and Staphylococcus aureus, 33.3%, 26.7% and 16.7%, respectively. Higher rates of leukocyte infiltration (P < 0.01) were observed in the uterine discharge and pyosalpinx than hydrosalpinx. In a conclusion, the current study disclosed that oviductal lesions seem to be an important problem in buffalo cows. In addition, there is no correlation between bacteria isolated from uterus and hydrosalpinx. There is a high correlation between bacteria isolated from uterus and pyosalpinx and salpingitis. The occurrence of pyosalpinx and salpingitis is mainly due to bacterial infection. Bacterial isolates from pyosalpinx and salpingitis might be related to ascending infection from the uterus.     

Identification of surgically-induced longitudinal lesions of the equine deep digital flexor tendon in the digital flexor tendon sheath using contrast-enhanced ultrasonography: an ex-vivo pilot study

Background

Longitudinal tears in the lateral aspect of the deep digital flexor tendon are the most common causes of pain localised to the equine digital flexor tendon sheath. However conventional ultrasonographic techniques provide limited information about acute lesions. Ultrasonographic contrast agents are newly developed materials that have contributed to advancement in human diagnostic imaging. They are currently approved for intravenous use in human and animal models. In this study we described intrathecal use in the horse. This study was undertaken to evaluate the reliability of standard and angle contrast-enhanced ultrasonography to detect and characterize surgically-induced longitudinal lesions in the deep digital flexor tendons.In this pilot study surgically-induced lesions were created in the lateral aspect of the deep digital flexor tendon within the digital flexor tendon sheath in 10 isolated equine limbs to generate a replicable model for naturally occurring lesions. Another 10 specimens were sham operated. All the limbs were examined ultrasonographically before and shortly after the intrasynovial injection of an ultrasound contrast agent containing stabilised microbubbles. The images were blindly evaluated to detect the ability to identify surgically-created lesions. The deep digital flexor tendons were dissected and a series of slices were obtained. The depth of longitudinal defects identified with contrast-enhanced ultrasound scans was compared to the real extent of the lesions measured in the corresponding gross tendon sections.

Results

Contrast-enhanced ultrasonography with both angle and standard approach provided a significant higher proportion of correct diagnoses compared to standard and angle contrast ultrasonography (p < 0.01). Contrast-enhanced ultrasonography reliably estimated the depth of surgically-induced longitudinal lesions in the deep digital flexor tendons.

Conclusion

Contrast-enhanced ultrasound of the digital flexor tendon sheath could be an effective tool to detect intrasynovial longitudinal tears of the deep digital flexor tendon, although an in vivo study is required to confirm these results for naturally occurring lesions.     

The emergence of Schmallenberg virus across Culicoides communities and ecosystems in Europe

Schmallenberg virus (SBV), a novel arboviral pathogen, has emerged and spread across Europe since 2011 inflicting congenital deformities in the offspring of infected adult ruminants. Several species of Culicoides biting midges (Diptera: Ceratopogonidae) have been implicated in the transmission of SBV through studies conducted in northern Europe. In this study Culicoides from SBV outbreak areas of mainland France and Italy (Sardinia) were screened for viral RNA. The role of both C. obsoletus and the Obsoletus complex (C. obsoletus and C. scoticus) in transmission of SBV were confirmed in France and SBV was also discovered in a pool of C. nubeculosus for the first time, implicating this species as a potential vector. While collections in Sardinia were dominated by C. imicola, only relatively small quantities of SBV RNA were detected in pools of this species and conclusive evidence of its potential role in transmission is required.