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Efficacy of tulathromycin injectable solution for the treatment of naturally occurring Swine respiratory disease 总被引:4,自引:0,他引:4
Nutsch RG Hart FJ Rooney KA Weigel DJ Kilgore WR Skogerboe TL 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):214-224
Tulathromycin, a novel triamilide antimicrobial, was evaluated for treatment of swine respiratory disease (SRD) in field efficacy studies involving 720 pigs in six North American swine herds. In each study, feeder pigs with clinical SRD were randomly assigned in equal numbers to a group treated with tulathromycin given as a single injection at 2.5 mg/kg of body weight or to a saline-treated control group. Four of the studies included a third group treated with ceftiofur sodium for 3 consecutive days at 3 mg/kg of body weight. Pigs were treated on day 0 and evaluated for treatment response on day 7. In each study, 10 or more nontreated pigs and saline-treated pigs that did not respond to treatment underwent necropsies to obtain lung samples that were evaluated for SRD pathogens. The overall cure rate was 46.4% for saline-treated pigs, 71.1% for tulathromycin-treated pigs, and 63.1% for ceftiofur-treated pigs. The cure rate for tulathromycin-treated pigs was significantly higher than for saline-treated pigs (P = .0116). Mortality from SRD occurred in 24 control pigs, seven tulathromycin-treated pigs, and one ceftiofur-treated pig. The mortality rate was significantly lower for both the tulathromycin- and ceftiofur-treated pigs compared with those treated with saline (P = .0148 and P = .0195, respectively). Actinobacillus pleuropneumoniae, Pasteurella multocida, Haemophilus parasuis, and Mycoplasma hyopneumoniae, bacteria commonly associated with SRD, were isolated from SRD-affected pigs. Under field conditions, tulathromycin injectable solution given as a single IM dose of 2.5 mg/kg of body weight was safe and effective in the treatment of SRD. 相似文献
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B L Hart 《Veterinary Clinics of North America: Small Animal Practice》1991,21(2):225-237
Dogs and cats that are ill with febrile diseases usually are depressed and anorexic. When viewed from the standpoint of the wild ancestors, it is apparent that the behavior of sick animals is adaptive and not necessarily a reflection of debilitation. A wild animal that is acutely ill with an infectious disease often is at a life-or-death juncture, and its behavioral mode may be seen as putting the animal's resources into facilitating the fever response in combating the pathogens. 相似文献
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利用20头8日龄黑白花公犊研究开食料中添加乙酸钠和瘤胃酶制剂对其生长发育的影响,持续60天。结果表明:开食料及添加剂对公犊生长有明显的促进作用。试验组总增重、胴体、腓肠肌重以及瘤网胃重量均显著高于对照组,分别为:31.3±1.33kg,37.2±1.16kg,0.624±0.02kg,1.30±0.07kg。而对照组相应为:26.70±0.95kg,33.3±1.16kg,0.555±0.01kg,1.06±0.04kg。肌肉组织代谢分析表明:开食料及添加剂具有加强组织代谢,促进肌肉蛋白合成之功效。试验组腓肠肌总RNA 和 RNA/干重比对照组分别提高20.89%(P<0.01)和10.83%(P<0.01),GPT/DNA 增加46.32%(P<0.05)。血清三碘甲腺原氨酸(T_3)浓度提高14.28%(P<0.05)。提示:开食料中添加乙酸钠和瘤胃酶制剂能促进瘤胃发育,改善代谢过程,提高生长速度。 相似文献
408.
Clifford A. Hart 《Pest management science》1979,10(4):341-357
The efficacy of a pesticidal formulation is in part affected by the surface to which it is applied. During the drying process, spray drops can interact with the complex microenvironment of trichomes, secretory glands, stomata, epicuticular wax and cuticle of the leaf epidermis. The subsequent uptake and persistence of the deposit can be further influenced by the action of the microclimate, including humidity, temperature, rain and dew. The scanning electron microscope (SEM), which is an instrument ideally suited for the study of the surface of bulk specimens, has been used to show the spreading and distribution of pesticides applied as sprays and individual drops to leaf surfaces. Particle size, crystal growth and co-precipitation of the active ingredient with surfactants and other adjuvants have also been investigated. The SEM can also show how some pesticides and their adjuvants continue to be taken up by the leaf long after the drops have visibly dried. Phytotoxicity, sometimes associated with the penetration of active ingredient or formulation adjuvant, can also be demonstrated using the microscope, especially if either specifically emits cathodoluminescence. These images can also supply complementary information concerning the persistence of deposits, provided that interpretation of the results is carried out with care and, if possible, in conjunction with residue and biological assays. 相似文献
409.
Critical anthelmintic tests and controlled trials were used to assess the efficiency of laevo -tetramisole hydrochloride against nematode infections in sheep and cattle.
In sheep, oral dose rates of 5 mg/kg and above were 94 to 100% effective against adult Haemonchus contortus , intestinal Trichostrongylus spp, Nematodirus spp, Oesophagostomum columbianum, O. venulosum and Chabertia ovina . A dose rate of 7.5 mg/kg was required for consistently high activity against Ostertagia spp, but activity against Trichostrongylus axei remained variable at this dose level. Efficiency against Trichuris ovis ranged from 76 to 100% at a dose rate of 10 mg/kg. The drug was 94 to 100% effective against 7-day old and 14-day old H. contortus , intestinal Trichostrongylus spp and O. colun bianum infections, and 83 to 89% effective against 14-day old Ostertagia spp and T. axei , at a dose rate of 5 mg/kg. Seven-day old Ostertagia spp larvae were highly resistant at a dose rate of 10 mg/kg, while activity against T. axei infections of the same age appeared variable at 5 and 10 mg/kg.
In cattle, subcutaneous treatment at dose rates of 1.5 mg/kg and above, and oral treatment at 7.5 mg/kg, were 93 to 100% effective against adult Haemonchus placei , intestinal Trichostrongylus spp, Nematodirus helvetianus, Cooperia spp and Oesophagostomum radiatum , and 84 to 98% effective against Ostertagia ostertagi . Against Trichostrongylus axei , a rate of 5 mg/kg subcutaneously was 83% effective, and a rate of 7.5 mg/kg orally 97% effective, while these dose rates gave 88 to 100% clearance of adult Dictyocaulus viviparous . 相似文献
In sheep, oral dose rates of 5 mg/kg and above were 94 to 100% effective against adult Haemonchus contortus , intestinal Trichostrongylus spp, Nematodirus spp, Oesophagostomum columbianum, O. venulosum and Chabertia ovina . A dose rate of 7.5 mg/kg was required for consistently high activity against Ostertagia spp, but activity against Trichostrongylus axei remained variable at this dose level. Efficiency against Trichuris ovis ranged from 76 to 100% at a dose rate of 10 mg/kg. The drug was 94 to 100% effective against 7-day old and 14-day old H. contortus , intestinal Trichostrongylus spp and O. colun bianum infections, and 83 to 89% effective against 14-day old Ostertagia spp and T. axei , at a dose rate of 5 mg/kg. Seven-day old Ostertagia spp larvae were highly resistant at a dose rate of 10 mg/kg, while activity against T. axei infections of the same age appeared variable at 5 and 10 mg/kg.
In cattle, subcutaneous treatment at dose rates of 1.5 mg/kg and above, and oral treatment at 7.5 mg/kg, were 93 to 100% effective against adult Haemonchus placei , intestinal Trichostrongylus spp, Nematodirus helvetianus, Cooperia spp and Oesophagostomum radiatum , and 84 to 98% effective against Ostertagia ostertagi . Against Trichostrongylus axei , a rate of 5 mg/kg subcutaneously was 83% effective, and a rate of 7.5 mg/kg orally 97% effective, while these dose rates gave 88 to 100% clearance of adult Dictyocaulus viviparous . 相似文献
410.
Ontogeny of gut-associated lymphoid tissue (GALT) in the dogfish Scyliorhinus canicula L 总被引:1,自引:0,他引:1
Cartilaginous fish occupy a fundamental position in vertebrate phylogeny and it is likely that this group has retained some of the ancestral immune mechanisms. The ontogeny of GALT has received little attention in elasmobranchs and this study correlates this development with morphological differentiation, development of other lymphoid organs, exposure to seawater and transition from yolk dependence to exogenous food as a source of nutrient. GALT was first represented by individual lymphocyte-like and macrophage-like cells in the lamina propria. In later stages accumulations and intraepithelial leucocytes were recorded prior to hatching. The size of accumulations and the number of lymphocyte and macrophage-like cells infiltrating the lamina propria and epithelium increased in fish as they became dependent upon an exogenous diet. Although GALT developed after the thymus and lymphoid-like tissue in the kidney and at approximately the same time as the epigonal, Leydig and spleen, the source of cells populating the gut is unknown. Plasma cells and granulocytes were not observed in the developing fish until 6 months post-hatch after which the fish had a similar GALT distribution and content to the adult fish. 相似文献