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71.
Embryo transfers from mares in athletic competition 总被引:1,自引:0,他引:1
The objective of this project was to produce multiple pregnant recipient mares during one year from each of four mares which were in athletic training and competition. Twenty-six embryos were recovered from the four mares in 38 collection attempts. Each embryo was surgically transferred to one of 20 recipient mares. Nine of 10 recipient mares which were transferred to on one occasion were detected pregnant at the one week post transfer pregnancy examination and six of eight mares which were transferred to on two occasions were detected pregnant at one of the one-week post transfer pregnancy examinations. Three of the 15 pregnant recipient mares lost their pregnancies by day 150. The 12 resulting pregnant recipient mares from the four competing donor mares demonstrated that donor mares can remain in athletic competition and at the same time provide viable embryos for embryo transfer. 相似文献
72.
Adrian Steiner 《Veterinary Clinics of North America: Food Animal Practice》2003,19(3):647-660
Little clinically relevant, evidence-based data about the effect of motility modifiers on the GI tract of cattle are currently available. Additionally, some of the published results seem to be contradictory. Three main facts explain this apparent discrepancy: (1) Results may not be transferred from one species to another, because presence, concentration, location, distribution, and function of specific receptors may differ significantly among species. (2) The lack of a significant effect on smooth muscle preparations in vitro does not necessarily exclude a certain drug's motility-modifying property on affected animals in vivo. Certain drugs bind to receptors outside the myenteric plexus. Others, such as lidocaine and adrenergic-, dopaminergic-, and opioid-antagonists increase only GI motility, if inhibitory reflexes or a hyperactive state of the inhibitory sympathetic nervous system preexists. (3) Effects of motility modifiers as found in healthy experimental animals in vivo may not be similar to those found in spontaneously diseased animals. Accurate and reliable data on the effect of modifiers of GI motility of cattle will be obtained only from double-blinded, evidence-based, in vivo studies on spontaneously affected animals. Because well-documented results from such studies are extremely rare, intensive research in this field is warranted in the future. 相似文献
73.
74.
Following the hypothesis that metabolic screens may be useful tools in the diagnosis of canine aggression we have investigated the blood plasma amino acid levels of dogs which have been found aggressive (N = 10) against dogs or men in comparison to non-aggressive dogs (N = 10). In summary, the aggressive dogs showed elevated plasma concentrations of the neurophysiological active aromatic amino acids tryptophan (46/171 micromol/l, p < 0,001), tyrosine (38/67 micromol/l, p < 0.01) and histidine (74/91 micromol/l, p < 0.01) and lower lysine concentrations (175/151 micromol/l, p < 0.05), which seems to point to a stress situation of these dogs. The nitrogen metabolism is impaired in the urea-cycle in the conversion of ornithine (17/34 micromol/l, p < 0.01) to citrulline (64/47 micromol/l). Higher levels of branched chain amino acids, especially leucine (122/150 micromol/l, p < 0.01), mainly metabolized in muscles, and isoleucin (60/71 micromol/l, p < 0.05) show a high energy potential.The acidose-stimulator methionine (48/78 micromol/l, p < 0.01) proved elevated. The results show that the changed behavior in the aggressive dogs is also reflected in their free amino acid plasma concentrations, independent of the question whether these data are the cause or the result of the aggressivity. 相似文献
75.
Judith Hübschen Lilo Kling Ulrike Ipach Volker Zinkernagel Derek Brown Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(9):883-891
The nematode species Longidorus attenuatus, L. elongatus, L. macrosoma and Paralongidorus maximusare economically important pests to the viticulture industry due to their ability to vector two nepoviruses (Raspberry Ringspot Virus and Tomato Black Ring Virus) to grapevines. In Germany, these species occur in vineyard soil with other non-vector but morphologically similar longidorid species, L. helveticus, L.profundorum and L. sturhani. Species-specific primers were designed from ribosomal DNA for all seven species to facilitate taxonomic identification for non-specialists. Primers were assessed for their reliability by screening, where possible, a number of populations of each species. Furthermore, their selectivity and sensitivity were determined when challenged with closely related longidorid species and general nematode communities typical of vineyard soil. A multiplex approach using a common forward primer combined with species-specific reverse primers enabled three target nematode species to be detected in the same PCR reaction. All primers were highly specific, detecting all nematode developmental forms from disparate populations and were sufficiently sensitive to detect a single target nematode within a whole nematode community typical of a vineyard soil comprising of a range of non-target species. Given their specificity, sensitivity and reliability, these diagnostic primers should be of great benefit to both phytosanitary/quarantine services related to the viticulture industry and also as a decision management tool for growers. 相似文献
76.
Tumulty JW Broussard JD Steiner JM Peterson ME Williams DA 《Journal of the American Animal Hospital Association》2004,40(2):120-123
Six dogs were entered into a 30-day, prospective, nonrandomized, uncontrolled clinical trial evaluating the effects of an oral preparation of budesonide on the hypothalamic-pituitary-adrenal (HPA) axis during therapeutic management of active inflammatory bowel disease. Oral budesonide, at a dose of 3 mg/m(2), was administered once daily. Upon entry and completion of the trial, serum basal cortisol, adrenocorticotropic (ACTH)-stimulated cortisol, endogenous ACTH concentration, serum alkaline phosphatase (SAP) activity, and urine specific gravity were evaluated, as well as owner assessment of glucocorticoid-associated side effects. Significant suppression of the HPA axis occurred. No significant differences in SAP activity, urine specific gravity, or owner-subjective assessments were detected. 相似文献
77.
Forman MA Marks SL De Cock HE Hergesell EJ Wisner ER Baker TW Kass PH Steiner JM Williams DA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(6):807-815
Serum feline trypsinogen-like immunoreactivity (fTLI) concentrations and abdominal ultrasound have facilitated the noninvasive diagnosis of pancreatitis in cats, but low sensitivities (33% and 20–35%, respectively) have been reported. A radioimmunoassay has been validated to measure feline pancreatic lipase immunoreactivity (fPLI), but the assay's sensitivity and specificity have not been established. In human beings, the sensitivity of computed tomography (CT) is high (75–90%), but in a study of 10 cats, only 2 had CT changes suggestive of pancreatitis. We prospectively evaluated these diagnostic tests in cats with and without pancreatitis. In all cats, serum was obtained for fTLI and fPLI concentrations, and pancreatic ultrasound images and biopsies were acquired. Serum fPLI concentrations ( P <.0001) and ultrasound findings ( P = .0073) were significantly different between healthy cats and cats with pancreatitis. Serum fTLI concentrations ( P = .15) and CT measurements ( P = .18) were not significantly different between the groups. The sensitivity of fTLI in cats with moderate to severe pancreatitis was 80%, and the specificity in healthy cats was 75%. Feline PLI concentrations were both sensitive in cats with moderate to severe pancreatitis (100%) and specific in the healthy cats (100%). Abdominal ultrasound was both sensitive in cats with moderate to severe pancreatitis (80%) and specific in healthy cats (88%). The high sensitivities of fPLI and abdominal ultrasound suggest that these tests should play an important role in the noninvasive diagnosis of feline pancreatitis. As suggested by a previous study, pancreatic CT is not a useful diagnostic test for feline pancreatitis. 相似文献
78.
Zanolari P Steiner A Meylan M 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2004,51(9-10):456-461
The effects of erythromycin on myoelectric activity of the spiral colon of dairy cows were investigated in a prospective study. Four Simmental x Red-Holstein crossbred cows of similar body weight and condition with seven pairs of bipolar electrodes implanted in the intestine (one each in the distal ileum, caecum and proximal colon, and four in the spiral colon) were included. Erythromycin lactobionate (1 mg kg(-1)) and 0.9% sodium chloride solution (NaCl) were administered to each cow in a random order. Erythromycin was diluted with NaCl and both treatments were administered slowly intravenously over a period of 5 min 1 h after onset of a phase III of the bovine colonic migrating myoelectric complex (bcMMC). A 3-6-day washout period was scheduled between trials. Significant differences between the results of the treatments were observed for spike duration in phase I as well as for spike duration and duration of spiking activity during phase II of the second bcMMC, which were significantly higher after erythromycin treatment than after NaCl. These findings suggest an indirect effect of erythromycin on colonic motility in cattle. 相似文献
79.
In fall 2004, a survey of a representative sample of 1185 Swiss suckler beef farmers was carried out by questionnaire (return rate 51.9%). 32.7% of the respondents castrated their calves without the help of a veterinarian, 37.8% mandated a veterinarian to carry out the castrations and 29.4% did not castrate their bull calves at all. On average, 8 calves were castrated per farm and year at an average age of 7 days when the castration was carried out by a farmer or 34 days when the castration was carried out by a veterinarian. Almost all farmers castrated their calves with the rubber ring, and a majority considered no other method as feasible. 73.9% of the veterinarians used the Burdizzo technique, 14.9% applied rubber rings, and 11.2% performed a surgical procedure. 22.6% of the farmers and 85.4% of the veterinarians used sedation; local anaesthesia was performed in 32.1% of the castrations carried out by farmers and in 84.5% of the castrations carried out by veterinarians. 65.7% of the farmers were concerned by the change of the Swiss Animal Protection Ordinance (2001), when pain relief became mandatory. 47.6% of these farmers changed their castration routine: 53.1% now mandated a veterinarian, 33.0% used sedation or local anaesthesia and 8.9% abandoned castration of their calves. 59.8% of the farmers intended to participate in a future course for laymen, to study and train the technique of local anaesthesia for castration. Castration of their calves is for many suckler beef farmers an inevitable husbandry procedure. The political goal, that all calves shall be castrated with local anaesthesia can only be reached when livestock owners are informed about the distress caused by the castration and convinced of the benefit of the local anaesthesia.Veterinarians are important information carriers in this process. The implementation also produces work, be it the more complex castration procedure or the education of the farmers who want to carry out the local anaesthesia themselves. 相似文献
80.
The preparation of nonaqueous microemulsions using food-acceptable components is reported. The effect of oil on the formation of microemulsions stabilized by lecithin (Epikuron 200) and containing propylene glycol as immiscible solvent was investigated. When the triglycerides were used as oil, three types of phase behavior were noted, namely, a two-phase cloudy region (occurring at low lecithin concentrations), a liquid crystalline (LC) phase (occurring at high surfactant and low oil concentrations), and a clear monophasic microemulsion region. The extent of this clear one-phase region was found to be dependent upon the molecular volume of the oil being solubilized. Large molecular volume oils, such as soybean and sunflower oils, produced a small microemulsion region, whereas the smallest molecular volume triglyceride, tributyrin, produced a large, clear monophasic region. Use of the ethyl ester, ethyl oleate, as oil produced a clear, monophasic region of a size comparable to that seen with tributyrin. Substitution of some of the propylene glycol with water greatly reduced the extent of the clear one-phase region and increased the extent of the liquid crystalline region. In contrast, ethanol enhanced the clear, monophasic region by decreasing the LC phase. Replacement of some of the lecithin with the micelle-forming nonionic surfactant Tween 80 to produce mixed lecithin/Tween 80 mixtures of weight ratios (Km) 1:2 and 1:3 did not significantly alter the phase behavior, although there was a marginal increase in the area of the two-phase, cloudy region of the phase diagram. The use of the lower phosphatidylcholine content lecithin, Epikuron 170, in place of Epikuron 200 resulted in a reduction in the LC region for all of the systems investigated. In conclusion, these studies show that it is possible to prepare one-phase, clear lecithin-based microemulsions over a wide range of compositions using components that are food-acceptable. 相似文献