Effect of dietary canthaxanthin and iodine on the production performance and egg quality of laying hens.

In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline membrane, and on inhibiting Salmonella growth in eggs stored at 30°C. Three hundred hens were reared in cages. Birds were divided into six feeding groups (10 hens × 5 repetitions) that were administered 0, 3 or 6 ppm of CX and 1 or 10 ppm of I with their diets. Laying rate, egg weights, and feed conversion ratios were controlled. The quality of fresh eggs was assessed in wks 25-26, 48-50 and 62-63 of hens lives. An additional batch of eggs was incubated at the temperature of 30°C, and egg quality changes were monitored on days 3, 6 and 9 of storage. Additionally, eggs collected from four experimental groups of hens whose diets had been iodated with 1 or 10 ppm of I and supplemented with 0 or 6 ppm of CX were infected under laboratory conditions with Salmonella, and incubated for 5 and 10 d. The laying rate, egg weights, and feed conversion ratio were significantly improved. Dietary inclusion of CX contributed to a higher resistance of the vitelline membrane of egg yolks, but only for fresh eggs. Vitelline membrane degradation during egg storage at 30°C was significantly counteracted by dietary inclusion of I at a dose of 10 ppm. The same I dose resulted in the complete inhibition of Salmonella growth until day 10 of incubation, but exclusively for eggs collected from 40-week-old hens. Dietary supplementation with 10 ppm of I was found to impart high level of resistance to the vitelline membrane against the growth of Salmonella in case of eggs stored at 30°C; therefore, I was found to be more beneficial by ensuring longer preservation than that of CX. However, dietary supplementation with CX was found to increase the resistance of vitelline membrane in fresh eggs.

The effect of disease prevention and health promotion on workplace productivity: a literature review.

This report was prepared by the Center for Disease Prevention and Health Promotion in the Institute for Health and Productivity Management as part of an effort to improve understanding of the connection between employee health and performance and to begin to identify new strategies through which treating health as an investment in human capital can lead to greater business success. Computer database searches of peer-reviewed literature published between 1993 and 1998 and manual reviews of 20 journals were used to identify research on the link between employee health and performance. Data was extracted to summarize the overall findings on the magnitude of health problems addressed by health promotion and disease prevention programs, and the impact of interventions on improving health risk, reducing medical care cost, and improving worker performance. From this summary, major conclusions on early detection of disease, the impact of behavior change programs, and appropriate care-seeking were drawn. This systematic review is supplemented with summaries of 15 seminal articles and descriptions of five leading-practices programs. The influence of developments in work/family issues, complementary and alternative medicine, and quality of care and health outcomes research are briefly discussed. Finally, a conceptual framework for studying the impact of health and productivity is described.

The effect of stimulus significance on relatively sustained (tonic-like) and relatively transient (phasic-like) aspects of electrodermal, heart rate, and eyeblink response.

To examine the influence of stimulus significance on more sustained as well as transient aspects of electrodermal, cardiac (HR), and eyeblink response, a 21-sec tone was sounded in one ear or the other. A click occurred during many tones, and a light followed offset by 9 sec. Four groups were studied: one pressed a pedal immediately on hearing any click; another only on click during tone in a specified ear; a third also responded only to the specified ear, but withheld press until the light; a fourth listened without any response. Results confirmed the important role of stimulus significance in each system whether between- or within-subject comparisons were made. Sustained responses were seen only when a significant signal was sought, involving in each case sustained HR deceleration, slowed blink rate, and heightened electrodermal level. Transient response to click and light also appeared only when there were significant signals. Response to tone-onset gave more ambiguous results. ANOVAs of response magnitude suggested that onset of nonsignificant tones might have elicited ORs, while binomial tests indicated these were not elicited with better than random frequency anywhere but on those trials occurring more frequently at the experiment's onset. Interpretations consistent with both the significance hypothesis and with a distinction between automatic and voluntary ORs can be made only here. Motor response had no effect on electrodermal or eyeblink response, and on HR was associated only with increased acceleration 1-2 sec after pedal-press. Studies using small motor responses to establish stimulus significance are therefore not likely to be substantially biased by the response itself.