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81.
The objective of this study was to design a protocol to separate spermatozoa from seminal plasma of raw llama semen without prior enzymatic treatment using a single-layer centrifugation with Androcoll-E (AE). Two experiments were performed: (a) samples were divided into three aliquots (1 ml) that were deposited on the top of 4, 5 or 6 ml of AE and were centrifuged at 800g for 20 min and (b) samples were divided into two aliquots (1 ml) that were deposited on the top of 4 ml of AE and were centrifuged at 600g or 1,000g for 20 min. Columns of 5 and 6 ml of AE showed a total sperm motility (TM) significantly lower, while in the 4 ml column, this parameter was not different from the TM of samples before the AE treatment. The percentage of spermatozoa with intact and functional membranes, normal morphology and intact acrosomes, as well as the percentages of sperm with highly condensed chromatin, was conserved (p ˃ .05) in the three column heights and in the two centrifugation speeds evaluated. In conclusion, the different column heights of AE (4, 5 and 6 ml) and the different centrifugation speeds used (600, 800 and 1,000g) allow separating spermatozoa of raw llama semen without enzymatic treatment, preserving the evaluated sperm characteristics. However, of all the studied treatments, centrifugation in the 4 ml column of AE at 800g would be the method of choice to process raw llama semen samples destined for reproductive biotechnologies.  相似文献   
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Reasons for performing study: No endoscopic examination of the nasolacrimal duct has been described before. In contrast with other imaging techniques, endoscopy provides a direct inspection of the intralumen and ductal mucosa in standing sedation. Objectives: To provide a reference against which the endoscopic and clinical features of obstructive nasolacrimal disease in the horse may be compared. Methods: Endoscopic examination of the nasolacrimal duct was performed in 10 French Thoroughbred bay mares with a 3 mm shaft diameter flexible fibrescope. The duct was divided into 3 zones (1, 2 and 3) from the nostril to the lacrimal sac. Results: Endoscopic examination of the nasolacrimal duct appeared to be quite easy to perform in Zones 1 and 2, while the ease or difficulty of examining Zone 3 depended on the weight and size of the horse for the position of the endoscope in the lacrimal canal. Conclusions: Endoscopic inspection has provided the possibility of a novel diagnostic approach to conditions of the nasolacrimal duct in horses. Potential relevance: Endoscopic examination of the nasolacrimal duct could help to diagnose and treat nasolacrimal diseases by performing sample withdrawal and duct irrigation.  相似文献   
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Objective To evaluate the safety and efficacy of mitomycin C (MMC) in prevention of canine corneal scarring. Methods With an in vitro approach using healthy canine corneas, cultures of primary canine corneal fibroblasts or myofibroblasts were generated. Primary canine corneal fibroblasts were obtained by growing corneal buttons in minimal essential medium supplemented with 10% fetal bovine serum. Canine corneal myofibroblasts were produced by growing cultures in serum‐free medium containing transforming growth factor β1 (1 ng/mL). Trypan blue assay and phase‐contrast microscopy were used to evaluate the toxicity of three doses of MMC (0.002%, 0.02% and 0.04%). Real‐time PCR, immunoblot, and immunocytochemistry techniques were used to determine MMC efficacy to inhibit markers of canine corneal scarring. Results A single 2‐min treatment of 0.02% or less MMC did not alter canine corneal fibroblast or keratocyte phenotype, viability, or growth. The 0.02% dose substantially reduced myofibroblast formation (up to 67%; P < 0.001), as measured by the change in RNA and protein expression of fibrosis biomarkers (α‐smooth muscle actin and F‐actin). Conclusion This in vitro study suggests that a single 2‐min 0.02% MMC treatment to the canine corneal keratocytes is safe and may be useful in decreasing canine corneal fibrous metaplasia. In vivo studies are warranted.  相似文献   
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Across the southeastern United States, changing disturbance regimes threaten the integrity of pine flatwoods, reducing their suitability as habitat for a variety of avian species, many of which are considered of conservation priority. Prescribed burning and roller chopping are management practices widely used in pine flatwoods to control shrubs and increase the growth of herbaceous vegetation. However, the impacts these treatments have on this system and its associated avian communities are largely unknown. We examined the effects of prescribed burning and roller chopping on pine flatwoods avian communities using a paired sample approach. Avian communities were compared between treated (e.g., burned) and untreated areas. We considered abundance and richness of all birds, but also groups of conservation concern, and those likely impacted by seasonal management practices (e.g., breeding and non-breeding categories, and woodland, successional-scrub, and grassland guilds). Dormant season burning resulted in decreases in avian species richness and abundance within the non-breeding, overwintering community. In situations where the maintenance or enhancement of this avian group is desired, growing season burning appears beneficial and should be used in preference to dormant season burning. Growing season burning benefited breeding avian communities, resulting in increases in species richness and abundance within this group. Dormant season roller chopping had no effect on species richness or abundance of any avian category or guild. Increases in abundance within breeding avian communities were observed following growing season roller chopping and a roller chopping/burning combination. Grazing, did not mediate the effects of prescribed burning or roller chopping on avian species richness or abundance. The use of dormant season burning is likely inappropriate in situations where conservation and management of non-breeding, overwintering species is a priority. The use of growing season roller chopping appears to provide a potential treatment alternative in situations where positive effects on breeding species are desired. Overall, maintenance of avian abundance and richness may be best achieved through the diverse application of prescribed burning and roller chopping based on season, frequency, and space.  相似文献   
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The destination of sewage sludge is a problem faced by sewage treatment plants (STPs). Many alternatives have been sought, such as the application of sewage sludge in degraded soils and in agriculture as fertilizer. However, due to the risk of contamination with pathogens and/or metals, the use of sludge should be done cautiously. By the habits that diplopods present, they have been considered good environmental indicators for soil analysis. In this study, animals from the Rhinocricus padbergi species were exposed to two sewage sludge samples from two STPs in the São Paulo State, for different periods. The midgut of the animals were removed and histologically processed and subjected to histochemical tests. It was detected the following tissular responses: clusters of haemocytes through the cells of the fat body layer, increase in the quantity of intracellular granules in the cells of the fat body layer, increase in the release of secretion vesicles of the intestinal epithelium, and intense vacuolization of the cytoplasm of epithelial cells. The results suggest the presence of toxic substances to the studied species in both sludge samples used.  相似文献   
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In human medicine, diagnosis of diabetic ketoacidosis (DKA) is usually based on measurement of capillary 3-β-hydroxybutyrate (3-HB) with a hand held ketone sensor. This study was conducted to determine if measurement of capillary 3-HB could be useful for the diagnosis and monitoring of canine DKA. Fifteen dogs with diabetic ketosis and 10 with DKA were evaluated. Paired measurements of 3-HB of capillary and venous blood samples were analysed by the electrochemical sensor and reference method. Use of capillary 3-HB measurement during DKA management was then evaluated through simultaneous measurements of capillary 3-HB, urinary AcAc and venous blood gas analysis. Good agreement between capillary and venous 3-HB measurement was detected by the electrochemical sensor and reference method. Monitoring treatment of DKA revealed a significant correlation between capillary 3-HB and acidosis markers, while no significant correlation was observed between AcAc and acidosis markers. A cut-off value of capillary blood 3-HB >3.8 mmol/L for diagnosis of DKA resulted in 70% and 92% sensitivity and specificity. The electrochemical sensor accurately measures 3-HB concentration in both capillary and venous blood samples, is accurate in diagnosing canine DKA, and appears to reflect the patient''s metabolic status during DKA treatment.  相似文献   
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A 27 kg, 6‐year‐old, male castrated German shorthaired pointer presented to the University of Missouri, Veterinary Teaching Hospital with the complaint of progressive exophthalmia of 2 years duration optical density (OD). Lack of retropulsion OD was noted on physical examination. Anterior segment examination OU and fundic examination OS did not reveal any abnormalities. Examination of the fundus OD revealed focal scleral indentation of the inferior nasal globe. The indentation changed location with globe movement OD. MRI and CT scan revealed a well‐circumscribed, approximately 2 cm in diameter mass located caudal and ventral to the affected globe that appeared to communicate with the nictitating membrane with absence of any bony involvement. A modified lateral orbitotomy was recommended and performed to remove the orbital mass and nictitating membrane en‐bloc. Histopathology and immunohistochemistry of the mass confirmed a diagnosis of nodular granulomatous episcleritis (NGE). Postoperatively, the dog developed absolute keratoconjunctivitis sicca (KCS). Examples of primary episcleral inflammation in the dog include diffuse episcleritis, NGE, nodular fasciitis, fibrous histiocytoma, proliferative conjunctivitis/keratoconjunctivitis, pseudotumor, and Collie granuloma. The etiology of these episcleral inflammations is presumed to be immune mediated. To our knowledge, this is the first report of NGE affecting the orbital region of a dog. Development of absolute KCS resulting from excision of the nictitating membrane is also supported by this case.  相似文献   
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