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81.
T. S. TAYLOR D.V.M. M.S. M. T. MARTIN D.V.M W. C. McMULLAN D.V.M. M.S. 《Veterinary surgery : VS》1981,10(3):136-138
The medical management of two horses with small intestine occluding abdominal abscesses was supported by surgical bypasses. In the first case the small intestine was transected proximal to the abscess and an end-to-side anastomosis performed distally; in the second case a side-to-side anastomosis was performed without bowel transection. The results suggest bowel transection with an end-to-side anastomosis to be the preferred procedure. 相似文献
82.
83.
Despite evidences that seminal leucocytes could affect semen quality, references for the frequency and concentration of these cells in bulls are not available. The aim of this study was to determine the normal concentration of leucocytes in beef bulls and to correlate this characteristic with semen quality. First, 57 bulls from artificial insemination centres were evaluated to obtain the normal leucocytary profile values. Next, 382 bulls were subjected to breeding soundness evaluation. The average concentration of leucocytes in bovine semen was 4.73 × 106/ml. Unsatisfactory bulls showed a higher number of leucocytes/field than that in the satisfactory ones. Logistic regression analysis revealed that the unsatisfactory bulls showed 6.5‐fold more chances of having higher leucocyte counts than satisfactory ones. Values of up to 1 leucocyte/field in the bull ejaculate are considered physiologically normal, whereas >5 leucocytes/field is associated with poor semen quality. 相似文献
84.
85.
OBJECTIVE: To describe a significant outbreak of foetal infection and subsequent losses due to bovine pestivirus on a 5200 ha beef breeding and fattening property in central Queensland. DESCRIPTION OF THE HERD: The affected herd consisted of 656 cows, including 269 recently purchased cows, and 221 heifers that were joined in December/January 1995/96. There were approximately 2500 cattle on the property. INVESTIGATION: Following the purchase of 269 cows in October 1995, which were mingled with the existing cow herd, losses were experienced due to foetal infection with bovine pestivirus. These losses were recorded between 1996 and 1999 as: reduced pregnancy rates, losses between pregnancy testing (midpregnancy) and branding (calves averaged 3 months-of-age), losses due to pneumonia and ill-thrift between branding and approximately 12 months-of-age, and losses due to ill-thrift and the chronic wasting form of mucosal disease thereafter. All surviving calves were tested for bovine pestivirus in 1997 at an average of 10 months. Fifty-three calves were identified as persistently infected with bovine pestivirus. A further 110 calf losses could reasonably be attributed to bovine pestivirus infection. Persistently infected cattle were always unthrifty compared to their virus negative counterparts. Only one persistently infected calf was identified, on the basis of severe ill thrift, in the 1997 birth cohort and none in 1998. CONCLUSIONS: This outbreak of foetal infection with bovine pestivirus resulted in significant production losses. These losses were recorded over the three years subsequent to the outbreak. Significant numbers of persistently infected calves were not evident among calves born in the two years after this outbreak. 相似文献
86.
Adsorption-desorption and isotopic-exchange isotherms for acids soils of known clay mineralogy indicated that when all the surfa? P accessible to the solution was considered, the bonding energy for phosphate decreased exponentially with site coverage. The soils differed markedly in the quantities of surface P held at sites of very high bonding energy, defined as those in equilibrium with a solution concentration < 1 μM; the values ranging from 9 μmol g?1 in a soil with 40 per cent gibbsite in the clay fraction, to 1 μmol g?1 in a soil with only 1 per cent gibbsite and no interlayered material. The reversibility of current P adsorption on soil surfaces depended on the immediate history of the soil sample. Complete reversibility occurred when soil, previously enriched with soluble P and stored for 4 to 5 months at constant temperature, was suspended in solutions of constant pH and ionic strength. It is suggested that irreversibility occurs due to incomplete attainment of equilibrium during the adsorption phase, a condition predisposed by high initial P concentrations (>1mM), and the use of soils that are naturally in dis-equilibrium because of recent fertilizer additions or severe depletion of P by plant uptake. 相似文献
87.
88.
S. M. TAYLOR T. R. MALLON J. BLANCHFLOWER D. G. KENNEDY S. A. HEWITT 《Journal of veterinary pharmacology and therapeutics》1993,16(1):48-54
Groups of parasite-free lambs which were either housed and fed hay arid concentrates or were grazing on pasture were dosed with the oral flukicides rafoxanide and triclabendazole and subsequent plasma Concentrations moni-tored. Peak plasma concentrations and areas under curves (AUC) of both chemicals were significantly reduced in the grazing compared with the housed lambs. In order to investigate the observation similar groups of lambs were dosed orally with chromium EDI'A and faecal throughput estimated. I t was observed that the rate of throughput was greater in the grazing lambs, leading to the conclusion that the differences in plasma concentrations of the flukicides was caused by a reduction in their absorption in the grazing lambs. The implications on flukicide efficacy and dose rates are discussed. 相似文献
89.
Seven races of Pseudomonas syringae pv. pisi were distinguished using eight differential cultivars of pea (Pisum sativum). Segregation among F2 populations of crosses between differential cultivars sequentially inoculated with races of P.s. pv. pisi provided evidence for four and possibly six putative resistance(R)/avirulence(A) gene pairs. R1, R2 and R3 are dominant resistance alleles at single loci, R4 is a dominant allele at a single locus which exhibits variable expression possibly dependent on genetic background. There is evidence that R3 and R4 are at linked loci. Homology tests provided proof of the occurrence of the alleles R2, R3 and R4 in more than one cultivar. Two other alleles, R5 and R6, were postulated to explain the observed segregation ratios in certain crosses.
It can be inferred that P.s. pv. pisi races 2, 3 and 4 each carry a different single a virulence gene, race 6 carries no apparent avirulence genes, and race 7 carries at least A2, A3 and A4. Race 1 carries Al, A3, A4 and possibly A6; race 5 carries A2, A4 and possibly A5 and A6. 相似文献
It can be inferred that P.s. pv. pisi races 2, 3 and 4 each carry a different single a virulence gene, race 6 carries no apparent avirulence genes, and race 7 carries at least A2, A3 and A4. Race 1 carries Al, A3, A4 and possibly A6; race 5 carries A2, A4 and possibly A5 and A6. 相似文献
90.
CS Wood SC Bennett D Cho BP Masterson JL Roberts CE Tanner CE Wieman 《Science (New York, N.Y.)》1997,275(5307):1759-1763
The amplitude of the parity-nonconserving transition between the 6S and 7S states of cesium was precisely measured with the use of a spin-polarized atomic beam. This measurement gives Im(E1pnc)/beta = -1.5935(56) millivolts per centimeter and provides an improved test of the standard model at low energy, including a value for the S parameter of -1.3(3)exp (11)theory. The nuclear spin-dependent contribution was 0.077(11) millivolts per centimeter; this contribution is a manifestation of parity violation in atomic nuclei and is a measurement of the long-sought anapole moment. 相似文献