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1.
The temporary dentitions of 18 to 39-week-old lambs with a very light or a very heavy parasite burden are compared. The heavily parasitised lambs developed longer temporary incisors which tended to protrude further forward in relation to the upper dental pad. They showed absolute hypocalcaemia and hypoalbuminaemia and relative hypophosphataemia and hypoproteinaemia and in the alveolar bone of the mandible there was a reduction in ash and matrix densities and matrix mineralisation. The incisor protrusion and lengthening may have been a consequence of the loss of supporting bone, but inappetance was likely to have been a factor contributing to the lengthening.  相似文献   
2.
Objective To compare cortisol responses to three corticotrophic preparations in normal dogs.
Animals Eight clinically normal dogs (four intact males, four intact females) of medium size.
Procedures Each dog received four treatments on four separate occasions in a duplicated Latin square pattern. Treatments were two adrenocorticotrophin (ACTH) preparations given intramuscularly at 2.2 U/kg, one of the ACTH preparations given intramuscularly at 1 U/kg and a synthetic polypeptide with ACTH-like activity (tetracosactrin, cosyntropin) given intravenously at 5 μg/kg. Plasma samples were taken for cortisol assay before and at 0.5, 1, 2 and 4 h after treatment.
Results Plasma cortisol concentrations were similar with the two ACTH preparations and at both dose rates. Tetracosactrin produced smaller mean peak cortisol concentrations, which tended to occur earlier than with ACTH, and smaller values for the area under the curve of plasma cortisol concentration from zero time to 4 h.
Conclusion The findings suggest that canine adrenal function can be tested adequately by giving ACTH intramuscularly at 1 U/kg and measuring plasma cortisol in samples taken at 0 and 2 h, or by giving tetracosactrin intravenously at 5 μg/kg and determining cortisol concentration at 0 and 1 h.  相似文献   
3.
Barramundi, Lates calcarifer (Bloch), were immunized with an experimental Vibrio harveyi bacterin via intraperitoneal injection, immersion and anal intubation. Both specific and non-specific immune parameters were measured to compare responses to bacterin after delivery by various methods. Elevated antibody activities in sera were found in all treatment groups with barramundi injected intraperitoneally displaying significantly higher antibody activity than the other groups. In addition, there was evidence of memory induction with a heightened antibody response in the intraperitoneally injected group only. Bacteriostatic assays indicated activity against V. harveyi in the sera of all bacterin-treated groups; again this activity was significantly higher in the intraperitoneally injected groups. There was no enhancement noted in head kidney macrophage phagocytic activity or in serum lysozyme levels.  相似文献   
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5.
Abstract

CASE HISTORY: A 15-mm diameter mass developed in the S/C tissue overlying the right lateral gluteal muscle of a 6½-year-old female Flat-coated Retriever.

PATHOLOGICAL FINDINGS: Cytological preparations following aspiration of the mass were highly cellular and consisted of a population of large polygonal cells containing single to multiple nuclei, large prominent nucleoli, and intracytoplasmic vacuoles. Histologically, the neoplasm consisted of similar large cells surrounded by thick fibrous connective tissue trabeculae. The large polygonal cells reacted positively with antibodies against vimentin, low- and high-molecular-weight variants of cytokeratin (AE1/AE3), but not with antibodies to desmin or glial fibrillary acidic protein (GFAP).

DIAGNOSIS: The clinical, gross, histological and immunohistochemical findings are similar to those reported for parachordomas in humans. Neither recurrence nor metastases were noted 18 months after surgical excision of the mass.

CLINICAL RELEVANCE: This is the first reported case of a possible parachordoma in a dog, a benign tumour with cytological features of malignancy.  相似文献   
6.
Extract

Pseudogout is a common condition in elderly people in which sudden onset of intense joint pain and synovitis develop. Peri-synovial calcium crystal deposition is the cause of the synovitis rather than the uric acid deposition in common gout. It is a rare condition in dogs, having only been reported twice before. Two dogs presenting with acute lameness and pyrexia showed many macrophages and occasional neutrophils containing intracellular crystals on cytological examination of synovial fluid. The crystals were single or multiple, small to large, clear, square or rhomboid-shaped, weakly birefringent and resembled those described for pseudogout. Occasional crystals were also present free in the matrix. Non-steroidal anti-inflammatory drugs that are effective in reducing pain in people with pseudogout provided no relief to either patient, but twice daily oral prednisolone therapy was successful. Dosage was gradually tapered as clinical signs improved over a period of 6 weeks.  相似文献   
7.
Numerical modeling of the orbital evolution of interplanetary dust particles revealed that, over the past 1.2 million years, the rate of accretion of dust by Earth has varied by a factor of 2 to 3. These variations display a 100,000-year periodicity and are anticorrelated with Earth's changing orbital eccentricity. Extraterrestrial helium-3 concentrations in a deep-sea sediment core display a similar periodicity but are 50,000 years out of phase with the predicted variations. Also, because collisions between large bodies in the asteroid belt are inevitable, it is expected that large-amplitude stochastic variations on 10(7)- to 10(8)-year time scales would be superimposed on the 10(5)-year periodic variations.  相似文献   
8.
9.
Freshwater bathing is one of the main treatment options available against amoebic gill disease (AGD) affecting multiple fish hosts in mariculture systems. Prevailing freshwater treatments are designed to be long enough to kill Neoparamoeba perurans, the ectoparasite causing AGD, which may select for freshwater tolerance. Here, we tested whether using shorter, sublethal freshwater treatment durations are a viable alternative to lethal ones for N. perurans (2–4 hr). Under in vitro conditions, gill‐isolated N. perurans attached to plastic substrate in sea water lifted off after ≥2 min in freshwater, but survival was not impacted until 60 min. In an in vivo experiment, AGD‐affected Atlantic salmon Salmo salar subjected daily to 30 min (sublethal to N. perurans) and 120 min (lethal to N. perurans) freshwater treatments for 6 days consistently reduced N. perurans cell numbers on gills (based on qPCR analysis) compared to daily 3 min freshwater or seawater treatments for 6 days. Our results suggest that targeting cell detachment rather than cell death with repeated freshwater treatments of shorter duration than typical baths could be used in AGD management. However, the consequences of modifying the intensity of freshwater treatment regimes on freshwater tolerance evolution in N. perurans populations require careful consideration.  相似文献   
10.
Finfish with asymptomatic Yersinia ruckeri infections pose a major risk as they can transmit the pathogen and cause clinical outbreaks in stock populations. Current tools have insufficient quantitative ability for accurately detecting the trace levels of Y. ruckeri typically associated with asymptomatic infection, necessitate invasive or lethal sampling, or require long processing times. This study presents a highly sensitive qPCR‐based method, targeting part of the Y. ruckeri 16S rRNA sequence, that is capable of detecting extremely low levels of Y. ruckeri in noninvasively collected faecal samples. Quantitative precision and accuracy of faecal sample analysis was consistent, despite the complexity of the faecal matrix. The assay demonstrated linearity over a six log‐wide dynamic range. Its limit of detection (LOD) and limit of quantification (LOQ) were 4 and 10 copies of the target sequence, respectively. Sensitivity of the assay was comparable to other qPCR‐based methods without requiring invasive or lethal sampling. Applicability as a screening strategy was tested using passively collected faecal samples. Asymptomatic Y. ruckeri infection was detected in all samples, although none of the fish exhibited overt infection. This method will be beneficial for finfish disease management if developed further as a noninvasive, screening tool against asymptomatic Y. ruckeri infection.  相似文献   
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