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  • Nigel A Evans
  • 2005
Tulathromycin is a novel triamilide antimicrobial that has been approved for use in the treatment and prevention of bovine respiratory disease and the treatment of swine respiratory disease in the European Union and the United States. The agent penetrates gram-negative bacteria well, and it exhibits mixed bacteriostatic and bactericidal activity.(More)
Doramectin, 25-cyclohexyl-5-O-demethyl-25-de(l-methylpropyl)avermectin A1a, was selected as the best of a series of novel avermectins prepared by mutational biosynthesis. The primary evaluation of its in vivo antiparasitic activity was carried out using a rat Trichostrongylus colubriformis model and a rabbit Psoroptes cuniculi model. In each case the new(More)
Selamectin, 25-cyclohexyl-25-de(1-methylpropyl)-5-deoxy-22, 23-dihydro-5-(hydroxyimino)-avermectin B1 monosaccharide, is a novel endectocide with a unique combination of efficacy and safety in dogs and cats following both oral and topical administration. The compound is active against fleas and ticks, intestinal hookworms and ascarids, and immature(More)
Among flatworms with parasitic and commensal modes of existence, parthenogenesis and asexual multiplication appear to be largely confined to the Digenea and Cestoda, the only parasitic platyhelminths that routinely utilize indirect life-cycles. Parthenogenesis is apparently restricted to a minority of adult digeneans and cestodes inhabiting their final(More)
Immunization of chickens by in ovo injection of Eimeria tenella parasite stages was investigated. Fertile Hubbard x Petersen broiler chicken eggs were injected through the air cell on d 18 of incubation with sporozoites, sporocysts, or oocysts of E. tenella. Injected doses were in the range of 1 x 10(2) to 1 x 10(6) sporozoites, 2 x 10(5) to 2 x 10(7)(More)
Immunization of chickens by in ovo injection of infective stages of 5 species of Eimeria was investigated. Fertile Hubbard x Petersen broiler chicken eggs were injected through the air cell on d 18 of incubation with oocysts of E. acervulina, E. maxima, E. mitis, E. praecox, or E. brunetti. Injected doses of all species ranged from 1 x 10(2) to 1 x 10(6)(More)
Evaluation of a wide range of avermectin derivatives for flea activity in an in vitro feeding screen using the cat flea, Ctenocephalides felis, revealed a narrow structure-activity relationship (SAR) with activity surprisingly associated with monosaccharides and especially their C-5-oximes. We discovered commercially exploitable flea activity in a single(More)
Seeds of the leguminous plant Millettia thonningii were shown to possess promising molluscicidal activity against Bulinus trunctatus. The size of the snails was an important determinant of their susceptibility to the molluscicide; specimens with shell lengths of 2 to 3 mm being more susceptible than snails 5 to 6 mm long.
Several novel 15-membered-ring macrolide agents (azalide 1, triamilides 2 and 3, and the azalide 3,6-ketal 4) were identified as potential antibacterial agents against Mannheimia (formerly named as Pasteurella) haemolytica, Pasteurella multocida, Haemophilus somnus and Actinobacillus pleuropneumoniae, important etiological agents of bovine and porcine(More)
The efficacy of tulathromycin in the treatment (phase 1) and prevention (phase 2) of bovine respiratory disease (BRD) was evaluated on commercial farms in France, Germany, Italy, and Spain. In phase 1, commingled cattle with clinical BRD were treated with tulathromycin (n = 128) or florfenicol (n = 125) on day 0. Similar percentages of animals showed(More)