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101.
Exogenous eFSH, follicle coasting, and hCG as a novel superovulation regimen in mares 总被引:3,自引:0,他引:3
S.A. Welch MS D.J. Denniston PhD J.J. Hudson DVM MS J.E. Bruemmer PhD P.M. McCue DVM PhD E.L. Squires PhD 《Journal of Equine Veterinary Science》2006,26(6):262-270
The objective of this study was to evaluate various equine follicle-stimulating hormone (eFSH) treatment protocols and the effect of “follicle coasting” on ovulation and embryo recovery rates in mares. Cycling mares (n = 40) were randomly assigned to one of four groups 7 days after ovulation: (1) 12.5 mg eFSH twice daily until follicles were 35 mm or larger; (2) 12.5 mg eFSH twice daily until follicles were 32 mm or larger; (3) 12.5 mg eFSH twice daily for 3.5 days followed by 12.5 mg eFSH enriched with luteinizing hormone (LH) twice daily until follicles were 35 mm or larger; and (4) 25 mg eFSH once daily until follicles were 32 mm or larger. Mares in groups 1 and 3 were injected with human chorionic gonadotropin (hCG) (2500 IU intravenously) at the end of eFSH treatment, whereas mares in groups 2 and 4 were given hCG approximately 42 and 54 hours, respectively, after the last eFSH treatment (“follicle coasting”). Nonsurgical embryo collection was performed 6.5 to 7.5 days after ovulation. Each mare experienced a nontreated estrous cycle before being reassigned to a second treatment. Ovulation rates for mares in treatment groups 1 to 4 were 3.3 ± 0.4, 4.1 ± 0.4, 3.5 ± 0.4, and 2.8 ± 0.4 (mean ± SEM; P < .05), respectively. One or more embryos were recovered from more than 80% of mares in each treatment group, and embryo recovery rate per flush was similar among treatment groups (1.9 ± 0.3, 2.6 ± 0.3, 1.9 ± 0.3 and 1.9 ± 0.3, respectively; P > .05). The overall embryo recovery rate was 2.1 ± 1.5 embryos per flush. In summary, ovulation rate was higher for mares treated with eFSH (3.4 ± 0.4) compared with non-treated controls (1.1 ± 0.2). Ovulation rate in mares in which hCG was delayed (follicle coasting) was higher (P < .05) when treatments were given twice per day versus once per day. Administration of equine luteinizing hormone (eLH) in conjunction with eFSH did not have an advantage over mares treated only with eFSH. 相似文献
102.
Noah D. Cohen VMD MPH PhD DACVIM G. Kent Carter DVM MS DACVIM Jeffrey P. Watkins DVM MS DACVS Michael S. O'Conor BS MS 《Journal of Equine Veterinary Science》2006,26(10):462-474
The objective of this prospective study was to determine the association between presence of abnormal radiographic findings attributed to orthopedic disorders of development (ARF) with subsequent performance among yearlings in Texas. The study population was 348 yearlings offered for sale at the Texas Summer Yearling Sale during 2002 and 2003 for which presale radiographs of limbs were available for review. Radiographs of yearlings were reviewed and presence of ARF were recorded. Additionally, the following data were recorded for each horse: identifiers [name of dam, name of sire, hip number, and name (when available)], year of sale, state of birth, and sales price. Subsequent performance data were obtained for each horse at the conclusion of their 2nd and 3rd years of life. Results indicated that no ARF was significantly associated with performance outcomes. Lesions of the proximal dorsal aspect of the sagittal ridge of the 3rd metacarpus/metatarsus resulted in significantly lower sales prices than either horses without this ARF or horses without any ARF. In conclusion, multiple radiographic abnormalities of Thoroughbred yearlings were not associated with reduced performance during the first 2 years of the racing careers of horses studied. Presence of some abnormalities, however, may be associated with reduced sales price. 相似文献
103.
B.P.A. Fonseca MS A.L.G. Alves PhD J.L.M. Nicoletti PhD A. Thomassian PhD C.A. Hussni PhD S. Mikail DVM 《Journal of Equine Veterinary Science》2006,26(11):507-516
The object of the current study was to evaluate the efficacy of thermography and ultrasonography in the diagnosis of thoracolumbar lesions in Quarter Horse athletes and associate the different types of lesions found with the athletic modality practiced. Twenty-four horses were admitted to the Surgery Service for Large Animals of the Veterinary and Animal Science Faculty, UNESP, Botucatu, Brazil, with complaints of back problems. All the horses were submitted for physical examinations to confirm the existence of thoracolumbar alterations and then for thermography and ultrasonography. Thermography was used to map the lesioned areas of this region and ultrasonography for lesion characterization. The lesions found were supraspinous desmitis, interspinous desmitis, dorsal intervertebral osteoarthritis, and impingement of the spinous processes or kissing spines. The existence of a relation between the type of event practiced by the horse and the type of lesion found was determined. In horses that competed in the barrel race, a predominance of lesions in the thoracic caudal, thoracolumbar, and cranial lumbar regions occurred, with intervertebral osteoarthritis and interspinous desmitis being the most common. In cutting horses, most of the lesions were observed in the caudal lumbar region, whereas horses competing in reining showed a preferential location for lesions in the middle lumbar, with a predominance of supraspinous desmitis and myositis. Thermography associated with ultrasonography was shown to be efficient in the diagnosis of the thoracolumbar lesions of these horses. 相似文献
104.
105.
Catriona M. MacPhail DVM DACVS Eric Monnet DVM PhD DACVS DECVS Davyd H. Pelsue DVM DACVS James S. Gaynor DVM MS DACVA 《Journal of Veterinary Emergency and Critical Care》2006,16(3):192-198
Objective: To determine changes in hemodynamic and cardiac energetic parameters in dogs after induction of portal hypertension and gastric ischemia. These blood flow alterations are similar to changes seen in splanchnic blood flow in dogs with gastric dilatation volvulus syndrome (GDV). Design: Original experimental study. Setting: Veterinary teaching hospital. Animals: Seven purpose‐bred, intact male dogs. Interventions: Standard midline laparotomy and median sternotomy were performed under general anesthesia. Dogs were instrumented to obtain arterial blood pressure, aortic flow, cardiac chamber pressures, central venous pressure, portal flow, and portal pressure. Colored microsphere technology was used for the determination of myocardial blood flow. Measurements and samples were obtained at baseline, following induction of portal hypertension, and after induction of portal hypertension and gastric ischemia. Measurements and main results: Left ventricular myocardial blood flow was increased from 81.8±20.1 mL/100 g/min at baseline to 127.7±57.2 mL/100 g/min (P=0.02) after induction of portal hypertension and gastric ischemia. Myocardial oxygen consumption increased from 142.2±27.4 J/min/100 g at baseline to 219.1±33.4 J/min/100 g (P=0.003) after induction of portal hypertension and gastric ischemia, but cardiac external work remained unchanged (13.67±6.2 to 13.27±9.6 J/min; P=0.78; power=0.79). Cardiac efficiency decreased from 11.6±6.1% at baseline to 7.6±5.1% (P=0.017) after induction of portal hypertension and gastric ischemia. Conclusions: Transfer of energy within the myocardium was less efficient after induction of portal hypertension and ischemia of the stomach wall. On the basis of these results, alterations in cardiac function associated with GDV may result from deterioration of cardiac efficiency. 相似文献
106.
John H. Rossmeisl Jr. DVM MS DACVIM Michael A. Higgins DVM Dennis J. Blodgett DVM PhD DABVT Matthew Ellis DVM Delbert E. Jones MS 《Journal of Veterinary Emergency and Critical Care》2006,16(3):208-214
Objective: To report the manifestations, history, and pathophysiologic basis of disease in 2 dogs with Amanita muscaria toxicosis. Case summaries: Two dogs were evaluated for an acute onset of gastroenteritis and seizures. A. muscaria toxicosis was suspected in each dog after confirmation of environmental exposure and visualization of ingested mushrooms in vomitus. The diagnosis was confirmed following identification of toxic Amanita metabolites in the urine and serum of each dog. Administration of supportive and symptomatic therapies resulted in the complete recovery of each animal. Unique information provided: Ingestion of the mushroom, A. muscaria, by dogs can result in acute gastrointestinal distress that precedes a potentially life‐threatening central neurologic syndrome characterized by seizures, tremors, and somnolence. Central nervous system dysfunction results primarily from the actions of ibotenic acid and its decarboxylation product, muscimol, which are analogues of the neurotransmitters glutamate and γ‐aminobutyric acid (GABA), respectively. Identification of these toxins in the urine and serum of affected dogs using high‐performance liquid chromatography (HPLC) provides a definitive diagnosis. 相似文献
107.
108.
GWENDOLYN L. CARROLL MS DVM Diplomate ACVA R. NEIL HOOPER DVM Diplomate ACVS MARGARET R. SLATER DVM PhD SANDEE M. HARTSFIELD DVM MS Diplomate ACVA NORA S. MATTHEWS DVM Diplomate ACVA 《Veterinary surgery : VS》1998,27(1):75-82
Objective—To determine the safety and efficacy of propofol, after detomidine-butorphanol premedication, for induction and anesthetic maintenance for carotid artery translocation and castration or ovariectomy in goats. Study Design—Case series. Animals—Nine 4-month-old Spanish goats (17.1 ± 2.6 kg) were used to evaluate propofol anesthesia for carotid artery translocation and castration or ovariectomy. Methods—Goats were premedicated with detomidine (10 μg/kg intramuscularly [IM]) and butorphanol (0.1 mg/kg IM) and induced with an initial bolus of propofol (3 to 4 mg/kg intravenously [IV]). If necessary for intubation, additional propofol was given in 5-mg (IV) increments. Propofol infusion (0.3 mg/kg/min IV) was used to maintain anesthesia, and oxygen was insufflated (5 L/min). The infusion rate was adjusted to maintain an acceptable anesthetic plane as determined by movement, muscle relaxation, ocular signs, response to surgery, and cardiopulmonary responses. Systolic (SAP), mean (MAP) and diastolic (DAP) arterial pressures, heart rate (HR), ECG, respiratory rate (RR), Spo2, and rectal temperature (T) were recorded every 5 minutes postinduction; arterial blood gas samples were collected every 15 minutes. Normally distributed data are represented as mean ± SD; other data are medians (range). Results—Propofol (4.3 ± 0.9 mg/kg IV) produced smooth, rapid (15.2 ± 6 sec) sternal recumbency. Propofol infusion (0.52 ± 0.11 mg/kg/min IV) maintained anesthesia. Mean anesthesia time was 83 ± 15 minutes. Muscle relaxation was good; eye signs indicated surgical anesthesia; two goats moved before surgery began; one goat moved twice during laparotomy. Means are reported over the course of the data collection period. Means during the anesthesia for pHa (arterial PH), Paco2, Pao2, HCO3, and BE (base excess) ranged from 7.233 ± 0.067 to 7.319 ± 0.026, 54.1 ± 4.6 to 65.3 ± 12.0 mm Hg, 133.1 ± 45.4 to 183.8 ± 75.1 mm Hg, 26.9 ± 2.6 to 28.2 ± 2.1 mEq/L, and -0.8 ± 2.9 to 1.4 ± 2.2 mEq/L. Means over time for MAP were 53 ± 12 to 85 ± 21 mm Hg. Mean HR varied over time from 81 ± 6 to 91 ± 11 beats/minute; mean RR, from 9 ± 8 to 15 ± 5 breaths/minute; Spo2, from 97 ± 3% to 98 ± 3%; mean T, from 36.0 ± 0.6±C to 39.1 ± 0.7±C. Over time, Spo2 and Sao2 did not change significantly; HR, RR, T, and Paco2 decreased significantly; SAP, DAP, MAP, pHa, Pao2, and BE increased significantly. HCO3 concentrations increased significantly, peaking at 45 minutes. Recoveries were smooth and rapid; the time from the end of propofol infusion to extubation was 7.3 ± 3 minutes, to sternal was 9.2 ± 5 minutes, and to standing was 17.7 ± 4 minutes. Median number of attempts to stand was two (range of one to four). Postoperative pain was mild to moderate. Conclusions—Detomidine-butorphanol-propofol provided good anesthesia for carotid artery translocation and neutering in goats. Clinical Relevance—Detomidine-butorphanol-propofol anesthesia with oxygen insufflation may be safely used for surgical intervention in healthy goats. 相似文献
109.
ELIZABETH A. MARTINEZ DVM Diplomate ACVA ANNE A. WOOLDRIDGE DVM SANDEE M. HARTSFIELD DVM MS Diplomate ACVA KATRINA L. MEALEY DVM Dipiomate ACVCP 《Veterinary surgery : VS》1998,27(3):279-283
Objective—To determine the neuromuscular effects of doxacurium chloride and to construct a dose-response curve for the drug in isoflurane-anesthetized dogs. Design—Randomized, controlled trial. Animals—Six healthy, adult, mixed-breed dogs (five female, one male) weighing 24.8 ° 2.8 kg. Methods—Anesthesia was induced with isoflurane in oxygen and maintained with 1.9% to 2.3% end-tidal isoflurane concentration. Paco2 was maintained between 35 and 45 mm Hg with mechanical ventilation. Mechanomyography was used to quantitate the evoked twitch response of the paw after supramaximal train-of-four stimulation of the superficial peroneal nerve. After baseline values were recorded, the dogs received one of three doses of doxacurium (2.0, 3.5, 4.5 μg/kg of body weight) or a saline placebo intravenously in random order. All dogs received all treatments with at least 7 days between studies. After drug administration, the degree of maximal first twitch depression compared with baseline (T,%) was recorded. Dose-response relations of doxacurium were plotted in log dose-probit format and analyzed by linear regression to determine effective dose (ED50 and ED90) values for doxacurium. Results—The median log dose-probit response curve showed good data correlation (r= .999) with estimates of the ED50 (2.1 μg/kg) and ED90 (3.5 μg/kg) for doxacurium in isoflurane-anesthetized dogs. Mean ± SD values for T1% (first twitch tension compared with baseline) at maximal depression after drug administration, onset (time from drug administration to maximal depression of T1%), duration (time from maximal depression of T1% to 25% recovery of T1%), and recovery (time from 25% to 75% recovery of T1%) times were 92%± 4%, 40 ± 5 minutes, 108 ± 31 minutes, and 42 ± 11 minutes for dogs treated with 3.5 μg/kg of doxacurium and 94%± 7%, 41 ± 8 minutes, 111 ± 33 minutes, and 37 ± 10 minutes for dogs treated with 4.5 μg/kg of doxacurium. Conclusion and Clinical Relevance—We conclude that doxacurium is a long-acting neuromuscular blocking agent with a slow onset of action. Doxacurium can be used to provide muscle relaxation for long surgical procedures in isoflurane-anesthetized dogs. Interpatient variability, particularly of duration of drug action, may exist in the neuromuscular response to the administration of doxacurium in dogs. 相似文献
110.