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21.
Routine Bovine Viral Diarrhoea Virus (BVDV) monitoring of a commercial beef herd in southern New South Wales over a 10-year period provided an opportunity to assess the impact of the introduction of BVDV on that herd. BVDV antibody testing provided strong evidence that the herd was initially free of BVDV (2009–2011). Testing from 2012 suggested BVDV had been introduced into the herd and this was confirmed in 2015 with the identification of persistently infected (PI) animals. Having become established in the herd, the owners then set out to eliminate BVDV from the herd. Antigen testing aimed at identifying PI animals revealed BVDV was already absent from the herd. Subsequent antibody testing confirmed that the herd was now free from BVDV. Despite the incursion of BVDV in this herd, there was little measurable impact on reproductive performance (pregnancy rates), although suspected increased calf losses from birth to calf marking were reported. This is the first time such self-clearance has been documented as part of a longitudinal study under Australian conditions.  相似文献   
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BACKGROUND: An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg?1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry  相似文献   
23.
Cold stress is one of the major abiotic factors that influence the productivity and geographical distribution of many agriculturally important crops like Hevea brasiliensis. Cultivation of H. brasiliensis in India is being extended to northeastern regions, where low temperature during winter adversely affects its survival, growth, and productivity. Developing cold-tolerant genotypes is a primary requisite to maximize the productivity under such challenging environmental conditions. However, lack of methods for early evaluation of cold tolerance in the newly developed clones and the extensive time required for assessing their tolerance in the field are major constraints for clonal selection. The present study was initiated with an objective to identify and characterize cold stress responsive miRNAs from H. brasiliensis that show stronger association with cold tolerance. Next generation sequencing using Illumina HiSeq method revealed the expression of 21 and 29 conserved miRNA (from clone RRIM 600) families in cold-stressed and control samples, respectively. Forty-two novel miRNAs were identified from this study. Upon differential expression analysis, eight conserved miRNAs were found commonly expressed in both the samples. When expression analyses were performed subsequently with six selected miRNAs in two Hevea clones (viz. RRII 105 and RRIM 600), miR169 showed a strong association with cold tolerance. miRNAs such as miR482 and miR159 also exhibited association with cold tolerance. This study suggests the possibility of employing these miRNAs as markers for cold tolerance after validation in more number of genotypes with varying levels of cold tolerance.  相似文献   
24.
An 8-month-old German Shepherd dog was presented for investigation of pelvic limb gait abnormality. Neurolocalization indicated a T3-L3 spinal cord lesion. The myelographic appearance was of an intramedullary lesion at T9/10, but upon subsequent magnetic resonance imaging it was determined that the mass was extramedullary. A diagnosis of nephroblastoma was made on histological examination. The imaging features of this rare tumor and the differentiation of intradural-extramedullary and intramedullary masses are discussed.  相似文献   
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Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 μg/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 μg/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality.  相似文献   
28.
Injury of the distal aspect of the deep digital flexor tendon (DDFT) is a recognized cause of lameness, but diagnosis is difficult. This study aimed to improve understanding of DDFT morphology and pathology using retrospective evaluation of magnetic resonance (MR) images. We hypothesized that: (1) The distal aspect of the DDFT in normal horses would have a repeatable proximal/distal pattern and symmetry between limbs and between lobes; (2) DDFT dimensions would be related to bodyweight, navicular bone dimensions and hoof size; (3) this symmetry and pattern would be lost in DDFT injury; and (4) DDFT size would increase with injury. MR images of 64 live horse limbs, 26 with no identified DDFT lesion and 38 with identified DDFT abnormalities, and 19 normal cadaver limbs were analyzed. Using standardized transverse images, measurements of DDFT cross-sectional area, medial-lateral (ML) width and dorsal-palmar depth were obtained at six preselected sites. A uniform distal to proximal shape pattern was identified in all horses. The flattened crescent shape at the insertion changed to a deeper bilobed shape more proximally, with the mid-navicular area having the greatest cross-sectional area. Strong ML (P < 0.0006) and left/right symmetry (P < 0.02) were observed. In addition, there was a strong association between DDFT cross-sectional area and horse weight (P = 0.005) and between DDFT and navicular bone ML width (P = 0.004). Symmetry between sides or between lobes was lost at sites with a unilateral lesion and correlation between horse weight and DDFT cross-sectional area was lost in the presence of lesions. DDFTs with core lesions had a consistent increase in cross-sectional area overall, but other lesion types had no significant increase in size. The shape and symmetry seen in normal tendons could be related to the mechanical demands placed upon individual lobes. The limited increase in cross-sectional area with injury may be explained by the restrictive structures of the hoof, possibly explaining the ongoing pain seen in such lesions.  相似文献   
29.
Objective— To describe anatomic considerations and arthroscopic technique in horses for arthroscopic removal of palmar/plantar osteochondral fragments from the proximal interphalangeal (PIP) joint. Study Design— Retrospective study. Animals— Adult horses (n=4) with osteochondral fragments of the palmar/plantar PIP joint. Methods— Arthroscopic removal of palmar/plantar osteochondral fragments within the PIP joint was performed with horses in dorsal recumbency under general anesthesia. Medical records of affected horses were reviewed to determine history; physical, lameness, and radiological findings; surgical technique; complications and outcome. Results— Two horses had lameness localized to the PIP joint. Two other horses had lameness suspected, but not confirmed to the pastern region. One of these horses had a history of intermittent lameness, but was not lame on admission. All horses had radiographic evidence of palmar/plantar osteochondral fragmentation within the PIP joint. Fragmentation was located abaxially in 2 horses in the hind limb and axially in 2 horses in the left forelimb. Osteochondral fragments were successfully removed via a palmar/plantar arthroscopic approach in all horses. Three horses returned to previous levels of athletic performance; 1 horse was used for trail riding instead of reining. Conclusions— Arthroscopy of the palmar/plantar pouch of the PIP joint allowed limited assessment of the joint and removal of osteochondral fragments. Clinical Relevance— Arthroscopy of the palmar/plantar PIP joint pouch for assessment and removal of osteochondral fragments is possible and should be considered when lameness is localized to this joint.  相似文献   
30.
Deep digital flexor tendon transection at the mid-metacarpus was performed in 20 horses with severe acute or chronic laminitis that was not responsive to conventional treatment. Sixteen horses improved within 72 hours, one horse worsened, and two horses were unaffected by the surgery. Eleven horses survived less than 1 month after surgery and six horses survived longer than 6 months. Three horses surviving longer than 6 months have remained lame and no horse has returned to athletic performance. Transection of the deep digital flexor tendon at the mid-metacarpus may decrease the pain associated with the acute refractory stage of laminitis and may be useful as an immediate salvage procedure; however, despite the early clinical improvement observed after tenotomy, the survival rate of affected horses may not be altered.  相似文献   
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