Optimal nutritional management of growing pigs is constrained by lack of quantitative information on the response of animals between 30 and 110 kg live weight to dietary energy content. Under 'ideal' conditions modern genotypes appear to adjust feed intake to maintain a constant DE intake over a much wider range of dietary energy concentrations than previously thought (Mullan et al, 1998). However, under commercial pen conditions, voluntary feed intake is lower, pigs respond in terms of both growth rate and feed conversion to dietary DE density considerably above the levels currently thought to maximise biological and economic responses. The present study was designed to provide information on the response of growing pigs to dietary energy content under ideal and commercial housing conditions for two growth periods 30-60kg liveweight and 60-100kg liveweight. The results of the pigs kept under individual (ideal) housed conditions were consistent with the literature in that they adjusted their voluntary feed intake with digestible energy density to maintain a constant energy intake. The results of the pigs kept in groups (commercial) housing conditions tended to increase their daily energy intake as the energy density of the feed increased. This increase in energy intake improved the growth rate of the pigs and increased the fat deposition of those pigs. Economic analysis of the experiments involving pigs in groups indicates that formulating diets to a least cost per megajoule of digestible energy is not the most profitable point to set the digestible energy density. Modelling programs need to be used to determine where the least cost per unit of growth of the pig occurs. This is the most economical digestible energy density to formulate too. This will have major impact on the cost of production of piggery operations as the cost of energy is the single most important parameter in the cost of producing a pig.

Optimal nutritional management of growing pigs is constrained by lack of quantitative information on the response of animals between 30 and 110 kg live weight to dietary energy content. Under 'ideal' conditions modern genotypes appear to adjust feed intake to maintain a constant DE intake over a much wider range of dietary energy concentrations than previously thought (Mullan et al, 1998). However, under commercial pen conditions, voluntary feed intake is lower, pigs respond in terms of both growth rate and feed conversion to dietary DE density considerably above the levels currently thought to maximise biological and economic responses. The present study was designed to provide information on the response of growing pigs to dietary energy content under ideal and commercial housing conditions for two growth periods 30-60kg liveweight and 60-100kg liveweight. The results of the pigs kept under individual (ideal) housed conditions were consistent with the literature in that they adjusted their voluntary feed intake with digestible energy density to maintain a constant energy intake. The results of the pigs kept in groups (commercial) housing conditions tended to increase their daily energy intake as the energy density of the feed increased. This increase in energy intake improved the growth rate of the pigs and increased the fat deposition of those pigs. Economic analysis of the experiments involving pigs in groups indicates that formulating diets to a least cost per megajoule of digestible energy is not the most profitable point to set the digestible energy density. Modelling programs need to be used to determine where the least cost per unit of growth of the pig occurs. This is the most economical digestible energy density to formulate too. This will have major impact on the cost of production of piggery operations as the cost of energy is the single most important parameter in the cost of producing a pig.

Behavioral weight loss programs have been shown to be effective for short-term weight loss, however the impact of these programs on dietary changes is unclear. This study examined the changes in participant’s diet and physical activity over the course of a 16-week Internet behavioral weight-loss program. A single-center randomized controlled trial was conducted from August 2008 to December 2008 in Lexington, KY, and sixty-six women whose mean (SD) age was 48.6 (10.8) years and body mass index was 31.8 (3.7) kg/m2 completed all dietary and physical measures. Participants received two face-to-face group sessions with a dietitian, at baseline and 4-weeks, in addition to 16 weekly behavioral weight loss lessons delivered via an Internet website. Participants showed a significant reduction in energy intake (1879.2±771.7 vs. 1372.9±423.7; p<0.001), dietary energy density (2.1±0.5 vs. 1.9±0.5; p=0.002) and a significant increase in diet quality score as measured by the HEI-2005 (53.9±9.9 vs. 57.4±10.6; p =0.002). Participants did not show significant differences in physical activity intensity, duration or energy expenditure. However, post hoc analysis revealed that those who adopted a healthy life style, such as eating more fruits and vegetables and being physically active, achieved greater weight loss than those who did not adopt a healthy lifestyle. Participation in this Internet behavioral weight loss program significantly improved dietary intake in adult women and did not significantly improve daily physical activity levels.