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Short-chain fructooligosaccharides (FOS) were supplemented to the diets of nine quarter horses ranging in age from 489 to 539 d with initial BW averaging 400.6 [+ or -] 21.2 kg. The objectives of this study were to determine the effects of dietary FOS on the fecal responses in terms of pH, the microbial population, and VFA concentrations. The horses were used in a 3 x 3 replicated Latin square design, fed according to NRC requirements, and their individual diets were supplemented with no FOS (CON), 8 g of FOS/d (LOW), or 24 g of FOS/d (HIGH) over three 10-d feeding periods. On the last 3 d of each 10-d feeding period, a single fecal sample was collected between 0730 and 0930. Fecal pH decreased linearly (P = 0.01) from 6.48 with the CON diet to 6.38 with the HIGH diet, but there was no change (P = 0.19 for linear effect) in fecal consistency among treatments. A quadratic effect (P < 0.01) was observed for fecal Escherichia coli population, but no difference (P = 0.88 for linear effect) was found in fecal Lactobacilli enumeration among treatments. The presence of fecal Bifidobacteria was unable to be confirmed and was therefore not reported. Fecal acetate concentrations increased linearly (P = 0.03), with means of 2.13, 2.18, and 2.52 mg/g of wet feces for CON, LOW, and HIGH treatments, respectively. Similarly, fecal propionate concentrations increased linearly (P = 0.01), with means of 0.58, 0.64, and 0.73 mg/g for CON, LOW, and HIGH treatments, respectively. Fecal butyrate concentrations also increased linearly (P = 0.02), with means of 0.40, 0.46, and 0.54 mg/g for CON, LOW, and HIGH treatments, respectively. Total VFA (P = 0.01) and lactate (P = 0.02) concentrations increased linearly, with total VFA means of 3.47, 3.69, and 4.25 mg/g for CON, LOW, and HIGH treatments, respectively, and lactate means of 0.36, 0.41, and 0.47 mg/g for CON, LOW, and HIGH treatments, respectively. Supplementing FOS in diets fed to yearling horses altered fecal microbial populations, fecal VFA concentrations, and pH. Key Words: Fecal, Fructooligosaccharide, Horse, Microbiology, Volatile Fatty Acids

The effects of pH, acetate, propionate, or butyrate concentration, and diet on acid resistance of fecal Escherichia coli and E. coli O157:H7 were determined by in vitro and in vivo experiments. The pH tested was from 4.0 to 8.0, and the VFA concentrations tested were 0 to 100 mM. The E. coli O157:H7 used was strain 505B. In an in vivo study, cattle were fed a grain-based diet, then either not switched or switched to a grain-based diet with 3% added calcium carbonate or two fiber-based diets (soybean hulls or hay). Acid resistance was expressed as viability after acid-shock at pH 2.0 for 1 h and 4 h for fecal E. coli and E. coli O157:H7, respectively. Enumeration methods used were multitube fermentation, agar plate, and petri-film methods. The E. coli O157:H7 was not found in continuous culture inocula or in vivo samples. The viability of fecal E. coli decreased linearly (P < 0.01) as the culture pH increased, and viability ofE. coli O157:H7 was highest (P < 0.01) when cultivated at pH 6.0. The viability of fecal E. coli and E. coli O157:H7 showed quadratic responses (P < 0.05) as acetate and butyrate concentrations increased at pH 7.2, with maximal acid resistance at 20 and 12 mM, respectively. As propionate concentration increased, the acid resistance was not different (P > 0.05) for fecal E. coli. Acid resistance of E. coli was induced by acetate and butyrate, even though the environmental pH was near neutral. Similar results were measured in the in vivo study, where viability after acid shock was more dependent on VFA concentration than on pH. Increasing the dietary calcium carbonate concentration also increased (P < 0.05) acid resistance of fecal E. coli. Results from these studies demonstrated that culture pH and VFA affect acid resistance of E. coli. Key Words: Diet, Escherichia coli, pH, Resistance, Volatile Fatty Acids

At base this is a textbook which will be of considerable use to undergraduates who wish to have a quick, concise guide to a particular area under question. It is [...]

The traditional route to skill was via apprenticeship but that word could mean many things, from exploitive apprenticeship to learning by regular service or learning from the master. During the second half of the nineteenth century learning by means of regular service was the most important form of apprenticeship in industry, especially in engineering, shipbuilding, printing and building. An apprentice who had served his time had a definite status but many industrial skills were learnt without the definite promise of reward, by migrating from machine to machine or shop to shop,and semi-skilled work was learnt by "following up," doing a full-time job while learning from the man above. In such cases the workers' control over the labor supply depended on the enforcement of seniority rules; classic cases being in cotton spinning and on the railways. The level of skill of course varied and is often hard to define. While Charles More has looked at skill in terms of earnings for the men and usefulness to the employer, Richard Price sees skill as one aspect, albeit a most important one, of the struggle between the men and the employer over the exercise of control at the workplace.

Discusses the abstract of the study 'Digestibility of sunflower screenings by beef cows,' presented at the American Society of Animal Science's Midwestern Branch conference on March 17-19, 2003, in Des Moines, Iowa.

Discusses the abstract of the study 'The effects of diet on the acid-resistance of Escherichia coli in feedlot steers,' presented at the American Society of Animal Science's Midwestern Branch conference on March 17-19, 2003, in Des Moines, Iowa.