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81.
Rodenticides. 总被引:1,自引:0,他引:1
Michael J Murphy 《Veterinary Clinics of North America: Small Animal Practice》2002,32(2):469-84, viii
Rodenticides are second only to insecticides in the prevalence of pesticide exposure. Hundreds of rodenticide products currently exist, yet only a handful of them are involved in most toxicoses of companion animals. The most commonly reported toxicoses in the United States are those caused by anticoagulant rodenticides, bromethalin, cholecalciferol, strychnine, and zinc phosphide. The pathophysiologic findings, diagnosis, and treatment of each of these five rodenticides are discussed. 相似文献
82.
围产奶牛饲养要点 总被引:1,自引:0,他引:1
AndreaMurphy 《乳业科学与技术》2002,25(1):44-50
在有效的饲养操作下,奶牛的产奶量、健康状况及繁殖性能可达到良好平衡。获得高的经济回报的关键在于上述三方面性能都能保持良好。围产期是奶牛在泌乳周期中进行泌乳和确保良好的健康、繁殖状况的一个关键契机。围产期指产犊前60天至产犊后60天。而围产期中最为关键的时间是产犊前21天至产犊后21天。围产期的饲喂及管理操作的正确性对于奶牛的干物质 相似文献
83.
Sparkes A Wray J Leece E de Risio L Murphy S Furneaux R Sansom J Coatesworth J 《The Veterinary record》2007,161(24):826; discussion 826-826; discussion 827
84.
Walsh MC Sholly DM Hinson RB Saddoris KL Sutton AL Radcliffe JS Odgaard R Murphy J Richert BT 《Journal of animal science》2007,85(7):1799-1808
Two 5-wk experiments were conducted to determine the effects of water and diet acidification with and without antibiotics on weanling pig growth performance and microbial shedding. In Exp. 1, 204 pigs (19.2 d of age) were used in a 3 x 2 factorial, with 3 dietary treatments fed with or without water acidification (2.58 mL/L of a propionic acid blend; KEM SAN, Kemin Americas, Des Moines, IA). Dietary treatments were: 1) control, 2) control + 55 ppm of carbadox (CB), and 3) dietary acid [DA; control + 0.4% organic acid-based blend (fumaric, lactate, citric, propionic, and benzoic acids; Kemin Americas)] on d 0 to 7 followed by 0.2% inorganic acid-based blend (phosphoric, fumaric, lactic, and citric acids; Kemin Americas) on d 7 to 34. In Exp. 2, 210 pigs (average 18.3 d of age) were fed 1 of 3 dietary treatments: 1) control, 2) control + 55 ppm of CB, and 3) control + 38.6 ppm of tiamulin + 441 ppm of chlortetracycline on d 0 to 7 followed by 110 ppm of chlortetracycline on d 7 to 35 (TC) with or without dietary acidification (same as Exp. 1) in a 3 x 2 factorial arrangement of treatments. For both experiments, the pigs were allotted based on genetics, sex, and initial BW [5.5 kg (Exp. 1) or 5.6 kg (Exp. 2)]. Pigs were housed at 6 or 7 (Exp. 1) and 7 (Exp. 2) pigs/pen. Treatments were fed in 3 phases: d 0 to 7, 7 to 21, and 21 to 35 (34 d, Exp. 1). Fecal grab samples were collected from 3 pigs/pen on d 6, 20, and 33 for measurement of pH and Escherichia coli. During phase 3 and overall in Exp. 1, pigs fed CB had greater (P < 0.001) ADG (overall ADG, 389 vs. 348, and 348 g/d, respectively), ADFI (P < 0.007, 608 vs. 559, and 554 g/d, respectively), and d 34 BW (P < 0.001, 18.8 vs. 17.3, and 17.3 kg, respectively) than pigs fed NC and DA. Phase 3 ADG was improved (P < 0.01) by water acidification across all diets. In Exp. 2, pigs fed CB and TC had greater ADG (P < 0.004; 315 and 303 vs. 270 g/d, respectively), ADFI (P < 0.01), and d 35 BW (P < 0.002; 16.7 and 16.2 vs. 15.1 kg, respectively) than pigs fed NC. There was a tendency (P < 0.08) for an improvement in ADG when DA was added to the NC or TC, but decreased ADG when DA was added to CB. 相似文献
85.
86.
Transmission of resistance to common scab from the diploid to the tetraploid level via 4x-2x crosses in potatoes 总被引:1,自引:0,他引:1
Summary Diploid potato clones selected for their reaction to common scab and their ability to produce 2n male gametes were used in a series of crosses to a susceptible tetraploid female parent (cv. Shepody). In addition, two tetraploid clones were also selected for their reaction to common scab and crossed with Shepody as a female parent. Results indicated that resistance to common scab can be effectively transmitted from the diploid to the tetraploid level via 4x-2x crosses. Diploid parents producing 2n pollen via either first division or second division restitution can be used to transmit scab resistance. A relatively small proportion of resistant individuals could be recovered from susceptible x susceptible crosses in both 4x-2x and 4x-4x combinations. The data support a previously developed hypothesis that scab resistance is relatively simply inherited. 相似文献
87.
Summary Plants were grown from seed of two-rowed wild barley, Hordeum spontaneum, and six-rowed brittlerachised barley. H. agriocrithon, collected in Ladakh, north-western India. Whereas the H. spontaneum remained true to type, segregation for morphological characters was observed in progeny rows grown from heads of H. agriocrithon plants. The H. agriocrithon heads also showed segregation for a biochemical character, the polypeptide pattern of the endosperm storage protein fraction (hordein). The H. agriocrithon seed therefore originated from natural hybridization between cultivated H. vulgare and weedy H. spontaneum. Crosses of H. vulgare and H. spontaneum gave progeny which resembled H. agriocrithon and showed similar hordein polypeptide segregation patterns. The results indicate that six-rowed brittle-rach ised barleys from the Himalayas have a similar origin to forms found in the Middle East, and that H. agriocrithon does not play a direct role in the evolution of barley. 相似文献
88.
Eileen A. Murphy John Dooley Herbert L. Windom Ralph G. Smith Jr. 《Water, air, and soil pollution》1994,78(1-2):61-72
Water samples from 78 private potable wells in southern New Jersey were collected for mercury analysis in 1991–1992. Analyses were performed for the quantification of reactive, volatile and methyl mercury species. Relationships of mercury with other water quality parameters were evaluated also. Total mercury concentrations varied from <1 ng L?1 to over 36 Μg L?1. The dominant forms in which mercury occurred in the wells sampled were Hg? and HgCl2?, although methyl mercury was present in some wells and comprised up to 8% of the total mercury in the ground water samples. 相似文献
89.
90.
Simons AL Renouf M Hendrich S Murphy PA 《Journal of agricultural and food chemistry》2005,53(10):4258-4263
The relationship between chemical structure and gut microbial degradation rates of 14 flavonoids, flavone, apigenin, chrysin, naringenin, kaempferol, genistein, daidzein, daidzin, puerarin, 7,4'-dihydroxyflavone, 6,4'-dihydroxyflavone, 5,4'-dihydroxyflavone, 5,3'-dihydroxyflavone, and 4'-hydroxyflavone, was investigated by anaerobically fermenting the flavonoids with human gut microflora (n = 11 subjects). Degradation rates for the 5,7,4'-trihydroxyl flavonoids, apigenin, genistein, naringenin, and kaempferol, were significantly faster than the other structural motifs. Puerarin was resistant to degradation by the gut microflora. Extensive degradation of flavonoids by gut microflora may result in lower overall bioavailability than those flavonoids that are slowly degraded because rapidly degrading flavonoids are less likely to be absorbed intact. 相似文献