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991.
BACKGROUND: Pimobendan (PIMO) is an inodilator that may have some beneficial effects in canine degenerative mitral valve disease (MVD). However, little information is available about its cardiac effects in dogs without systolic myocardial dysfunction. HYPOTHESIS: Compared to benazepril (BNZ), an angiotensin-converting enzyme inhibitor, PIMO may worsen valve regurgitation in early canine MVD. ANIMALS: Twelve Beagles with asymptomatic MVD were randomized into 2 groups (n = 6) receiving BNZ or PIMO at dosages of 0.25 mg/kg PO q24h and q12h respectively, for 512 days. METHODS: The study followed a blinded, randomized, prospective, and parallel group design. After day 512, the dogs were necropsied, and cardiac histopathology was performed in a blinded manner. RESULTS: A significant treatment effect was observed as soon as day 15 with increased systolic function in the PIMO group by comparison to baseline value as assessed by fractional shortening (P < .0001) and tissue Doppler variables (P = .001). Concurrently, the maximum area and peak velocity of the regurgitant jet signal increased (P < .001), whereas these variables remained stable in the BNZ group. Histologic grades of mitral valve lesions were more severe in the PIMO group than in the BNZ group. Moreover, acute focal hemorrhages, endothelial papillary hyperplasia, and infiltration of chordae tendinae with glycosaminoglycans were observed in the mitral valves of dogs from the PIMO group but not in those of the BNZ group. CONCLUSIONS AND CLINICAL IMPORTANCE: PIMO has adverse cardiac functional and morphologic effects in dogs with asymptomatic MVD. Additional investigation in dogs with symptomatic MVD is now warranted.  相似文献   
992.
The acute phase protein (APP) response was evaluated after prolonged transportation of pigs under commercial conditions. Elevated serum APP concentrations were observed in two groups of boars immediately after their arrival at a destination farm compared with within-animal control samples obtained one month later. The effect was more pronounced in the first group of pigs conveyed under average transport conditions (Transport 1, 24 h), although the second group was transported for a longer time period (Transport 2, 48 h) but in superior transport conditions. In a second trial, pigs were sampled before transport, on arrival at an abattoir (following 12 h transport), and at the slaughter-line (after 6 h lairage). Significant increases in major acute phase protein (Pig-MAP), haptoglobin, serum amyloid A, C-reactive protein, and a decrease in apolipoprotein A-I, were observed at slaughter. The results demonstrate that shipment of pigs by road can result in an APP response that is probably related to the stress of transport.  相似文献   
993.
The nervous form of Maedi-Visna (MV) infection was diagnosed in four lambs aged 4 and 6 months, belonging to three different Assaf flocks that were managed intensively for milk and meat production. The animals presented with hindleg ataxia that rapidly progressed to complete recumbency. Lesions consisted of a moderate to severe non-purulent encephalitis affecting mainly the cerebellar peduncles. MV virus was demonstrated in the damaged tissues by immunohistochemistry and polymerase chain reaction. The investigation demonstrated that the clinical presentation of the nervous form of MV which is reported to occur in adult sheep can also be observed in young animals.  相似文献   
994.
The purpose of this study was to determine whether intracameral commercial lidocaine 2% induces alterations on the rabbit corneal endothelium. Forty white rabbits received different substances inside the anterior chamber: group (G)1, no substance; G2 and G3 received lidocaine 2% with preservative in aqueous solution; G4 and G5, lidocaine 2% with preservative in gel solution; G6 and G7, the anesthetic preservative (metilparahydroxybenzoate 0.1%); and G8 and G9, lidocaine 2% without preservative in aqueous solution. The animals from G2, 4, 6 and 8 were sacrificed after 1 h, and from G3, 5, 7 and 9 after 24 h after injection of the substance inside the anterior chamber. The corneas were clinically evaluated and assessed by transmission and scanning electron microscopy. G1, 2, 6, 7, 8 and 9 animals had very similar characteristics in clinical, ultrastructural and morphometric evaluations; the G3 and G4 animals showed discrete edema and one animal in G5 had intense corneal edema. We conclude that lidocaine 2% with preservative induces few ultrastructural alterations in the corneal endothelial cells.  相似文献   
995.
A 6-year-old male, Belgian shepherd dog was presented with lethargy, oliguria, hematuria, and reluctance to move. The dog developed hypertrophic osteopathy secondary to renal pelvis transitional cell carcinoma. A nephrectomy was performed and after a year, the dog was completely asymptomatic, and no evidence of metastatic disease was present.  相似文献   
996.
An Arabian mare was referred for right granulosa-theca cell tumor (GTCT) evaluation. The mare was presented 4.5 years later for a left GTCT, after successfully conceiving and delivering a normal foal in the interim. The concurrent or nonconcurrent occurrence of bilateral GTCT in mares appears to be rare.  相似文献   
997.
A 6-year-old Labrador retriever-cross was evaluated for an abnormal gait and head carriage 6 weeks after suffering trauma. The dog was presented with an ambulatory tetraparesis and was reluctant to move his head. Myelography and computed tomography demonstrated a subluxation of the atlanto-occipital joint with compression of the spinomedullary junction and the brain stem by the occipital bone. Removal of the compressive part of the occipital bone resulted in improvement of the clinical signs within 6 weeks, and resolution of clinical signs occurred 8 months after surgery.  相似文献   
998.
The aims of this study were 1) to determine whether dairy cows can be induced to ovulate by the treatment with gonadotropin releasing hormone (GnRH) followed by prostaglandin F(2 alpha) (PGF(2 alpha)) during the early postpartum period and 2) to describe their ovarian and hormonal responses according to ovarian status. Cows were divided in two groups and received 10 microg of buserelin followed by 500 microg of cloprostenol 7 days apart starting from 21 (GnRH21, n=7) or around 37 days postpartum (GnRH37, n=7). The groups were further classified according to presence (-CL) or absence (-NCL) of functional corpora lutea (CL) on the day of GnRH treatment (d 0): GnRH21-NCL (n=4), GnRH21-CL (n=3) and GnRH37-CL (n=7). Ovarian morphology was monitored and the concentrations of P(4), E(2), FSH and insulin-like growth factor 1 (IGF-1) were measured. All cows ovulated after administration of GnRH. The P(4) levels of the GnRH21-NCL group from d 0 to d 5 were lower than those of the GnRH21-CL (P<0.05) and GnRH37-CL groups (P<0.01). In contrast, the E(2) levels of the GnRH21-NCL group within d 2 to d 6 were higher (P<0.05) than those of the other groups. Compared with the GnRH37-CL group, the GnRH21-NCL group had more small follicles on d 2 (P<0.05), d 3 (P<0.01) and d 4 (P<0.01) and more large follicles on d 5 (P<0.05). The induced CL and new ovulatory follicles were larger in the GnRH21-NCL group compared with the GnRH21-CL (P<0.001 and P<0.01) and GnRH37-CL groups (P<0.001 and P<0.05). IGF-1 did not differ among the groups. The GnRH21-NCL group had higher FSH levels than the GnRH21-CL (P<0.01) and GnRH37-CL groups (P<0.001) on d 0. Low P(4) and high FSH levels may suggest higher gonadotropin support on the enhanced ovarian morphology of the GnRH21-NCL group. PGF(2 alpha) treatment induced CL regression and subsequent ovulation in 3/4 (75%), 3/3 (100%) and 7/7 (100%) cows in the GnRH21-NCL, GnRH21-CL and GnRH37-CL groups, respectively. In conclusion, a 7-day GnRH-PGF(2 alpha) synchronization protocol can effectively induce dairy cows to ovulate as early as 21 days postpartum, regardless of ovarian status.  相似文献   
999.
OBJECTIVE: To determine effects of vaccination protocols with modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine on persistence and transmission of virus in pigs infected with a homologous isolate and determine clinical and virologic responses following heterologous viral challenge. ANIMALS: Four hundred forty 6- to 8-week-old PRRSV-na?ve pigs. PROCEDURES: Pigs were allocated into 5 groups. Groups A to D were inoculated with wild-type PRRSV VR2332. Group A (positive control pigs) received PRRSV only. Groups B, C, and D received modified-live PRRSV vaccine (1, 2, or 3 doses). Group E served as a negative control group. To evaluate viral transmission, sentinel pigs were introduced into each group at intervals from 37 to 67, 67 to 97, and 97 to 127 days postinoculation (DPI). To evaluate persistence, pigs were euthanized at 37, 67, 97, or 127 DPI. To assess clinical and virologic response after challenge, selected pigs from each group were inoculated at 98 DPI with a heterologous isolate (PRRSV MN-184). RESULTS: Mass vaccination significantly reduced the number of persistently infected pigs at 127 DPI. Vaccination did not eliminate wild-type PRRSV; administration of 2 or 3 doses of modified-live virus vaccine reduced viral shedding after 97 DPI. Previous exposure to wild-type and vaccine virus reduced clinical signs and enhanced growth following heterologous challenge but did not prevent infection. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggest that therapeutic vaccination may help to reduce economic losses of PRRSV caused by infection; further studies to define the role of modified-live virus vaccines in control-eradication programs are needed.  相似文献   
1000.
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