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OBJECTIVE: To evaluate the potential of an implant of a GnRH-agonist (deslorelin) to create a progesterone free animal suitable for studying progesterone (P4) metabolism in intact cows by measuring blood P4 and faecal P4 metabolites. METHODS: Experiment 1: Eighteen non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to one of three groups to study plasma P4 concentrations preceding an intravaginal insert. These groups comprised: i) a deslorelin group (GnRH-agonist implanted); ii) a PGF group receiving two injections of prostaglandin (PGF2alpha) 12 days apart; and, iii) an ovariectomised (OVX) group. An intravaginal device (CIDR) was inserted into the vagina of each animal and left in place for 11 days. Plasma P4 concentrations were measured during the study period. Experiment 2: Twelve non-lactating cycling Holstein-Friesian cows, 4 to 7 years old, were allocated to two groups: i) a deslorelin group (GnRH-agonist implanted); and ii) an ovariectomised group. Plasma P4 and faecal P4 metabolites (20-oxo-pregnanes, 20alpha-OH and 20beta-OH) were monitored for a period of 5 weeks. RESULTS: Experiment 1: Average plasma P4 concentration did not differ between the three groups (1.28, 1.43 and 1.55 ng/mL for deslorelin, OVX and PGF cows, respectively, P = 0.8) during the period of supplementation. Experiment 2: There was no difference in plasma P4 (mean plasma P4 < 0.02 ng/mL, P = 0.9) and faecal P4 metabolites between deslorelin and OVX cows 2 weeks after the implantation (P = 0.7). CONCLUSIONS: These data showed that a GnRH-agonist (deslorelin) implant may be used as an alternative to ovariectomy to create a progesterone free animal suitable for studying the metabolism of administered P4.  相似文献   
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Crystalluria results from oversaturation of urine with crystallogenic substance. However, oversaturation may occur as a result of in vitro as well as in vivo events. The microscopic appearance of crystals only represents a tentative identification of their composition because variable conditions associated with their formation, growth, and dissolution may alter their appearance. Definitive identification is dependent on physical methods such as optical crystallography, x-ray diffraction, and electron microscopic analysis.  相似文献   
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The medical records from 44 dogs with traumatic luxation of the cubital joint were reviewed. Closed reduction was performed in 35 dogs, and open reduction in 9 dogs. Excellent or good results were achieved in 31 of 35 dogs (88.6%) treated by closed reduction and in 5 of 9 dogs (55.6%) treated by open reduction. Collateral ligament repair, performed in 5 dogs, did not appear to affect the prognosis. Factors such as body weight and type and duration of external coaptation also did not appear to influence the outcome. Increased dysfunction associated with open reduction most likely was caused by the chronic nature of the dislocation, iatrogenic damage to the articular cartilage during reduction, or both. A good prognosis for return to normal function with minimal gait abnormality can be expected in most cases of traumatic luxation of the cubital joint treated by early closed reduction.  相似文献   
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Onion breeding lines known to be resistant to Pyrenochaeta terrestris showed, in several locations, root-pruning symptoms that have been usually associated with only the action of P. terrestris. Fusarium oxysporum f. sp. cepae was invariably isolated from affected roots and the stem-plate area of these pink-root-resistant lines. Symptoms not commonly associated with the action of Fusarium, including darkening of dry scales of yellow bulbs and a reddening of scales of white bulbs, were noted. Controlled tests were conducted to establish (a) the pathogenicity of four isolates of F. oxysporum f. sp. cepae, (b) the reaction of onion breeding lines to inoculation at various temperatures with both the pink root and the Fusarium bulb rot organism, and (c) the pathogenic interaction of F. oxysporum f. sp. cepae with P. terrestris. The Fusarium isolates were pathogenic over a wide range of temperatures (20 to 38°C.). Host reaction to the organisms in combination depended on the level of susceptibility that was the greater to one or the other organism. Resistance to one did not markedly modify susceptibility to the other when both were present. Resistance to F. oxysporum f. sp. cepae was found in several onion lines.Horticulturist, Pathologist, and Horticulturist, respectively, United States Department of Agriculture, Beltsville, Maryland, U.S.A.  相似文献   
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Rotaviruses (RV) have a high prevalence in piggeries worldwide and are one of the major pathogens causing severe diarrhoea in young pigs. RV species A, B, and C have been linked to piglet diarrhoea in Australian pig herds, but their genetic diversity has not been studied in detail. Based on sequencing of the structural viral protein 7 (VP7) RVA G genotypes G3, G4 and G5, and RVC types G1, G3, G5, and G6 have been identified in Australian piggeries in previous studies. Although occurrence of RVB was reported in Australia in 1988, no further genetic analysis has been conducted. To improve health management decisions in Australian pig herds, more information on RV prevalence and genetic diversity is needed. Here, 243 enteric samples collected from 20 pig farms within Eastern Australia were analysed for the presence of RV in different age groups using a novel PCR-based multiplex assay (Pork MultiPath™ enteric panel). RVA, RVB, and RVC were detected in 10, 14, and 14 farms, respectively. Further sequencing of VP7 in selected RV-positive samples revealed G genotypes G2, G5, G9 (RVA), G6, G8, G14, G16, G20 (RVB), and G1, G3, G5, G6 (RVC) present. RVA was only detected in young (<10 weeks old) pigs whereas RVB and RVC were also detected in older animals (>11 weeks old). Interestingly, RVB and RVC G-type occurrence differed between age groups. In conclusion, this study provides new insights on the prevalence and diversity of different RV species in pig herds of Eastern Australia whilst demonstrating the ability of the Pork MultiPath™ technology to accurately differentiate between these RV species.  相似文献   
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