Eighty Holstein-Friesian cows were randomly assigned to four treatment groups of 20. The four groups of twenty cows were fed on diets that were designed to place cows at some degree of risk of ruminal and metabolic acidosis. The cows were fed either 10 kg of pellet and ate pasture, or a subgroup of six cows per group was fed 10 kg of pellet with ad lib forage in a Calan gate facility. Cows in G...

Antibiotics may enter the terrestrial environment when amending soils with manure. A Note of Guidance on ecological risk assessment of veterinary medicines was issued in January 1998. Hardly any information about ecotoxicological effects of already existing substances are available. This study has tested the effects of two widely used antibiotics, tylosin and oxytetracycline, on three species o...

With increasing pressures to reduce or eliminate the use of antimicrobials for growth promotion purposes in production animals, there is a growing need to better understand the effects elicited by these agents in order to identify alternative approaches that might be used to maintain animal health. Antibiotic usage at subtherapeutic levels is postulated to confer a number of modulations in the ...

Long-term feedlot studies have shown positive effects (i.e., improved ADG and reduced morbidity and mortality) of dietary supplementation with ethoxyquin (AGRADO). This may be due to improving the antioxidant capacity at the ruminal, postruminal, or postabsorption levels. This study was designed to investigate the role of ethoxyquin at the rumen level. A finishing diet (12.5% CP; DM basis) was ...

The antimicrobial susceptibility of clinical isolates of Brachyspira hyodysenteriae in Spain was monitored, and the underlying molecular mechanisms of resistance were investigated. MICs of tylosin, tiamulin, valnemulin, lincomycin, and tylvalosin were determined for 87 B. hyodysenteriae isolates recovered from 2008 to 2009 by broth dilution. Domain V of the 23S rRNA gene and the ribosomal prote...

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He,Yang. M.S.E., Purdue University, December, 2013. Photochemical reactions of Naproxen, Ibuprofen and Tylosin. Major Professor: Inez Hua. Pharmaceuticals and personal care products (PPCPs) include a wide range of compounds that are used extensively and sometimes daily by people. Some PPCPs have been detected in surface water (streams, rivers, lakes) due to incomplete removal in wastewater trea...

Abstract Carbon-based solid acids have been successfully employed as acidic catalysts for pollutant mitigation in wastewater. To fully tap the potentials of commercially viable carbons preparation and enhance their catalytic performances is a challenging problem. In this work, three commercialized including biochar, activated carbon graphite were preprocessed (ball-milling, Hummer exfoliation, ...