Nutrition Decisions Research Articles

Estimation of voluntary intake and digestibility of grass by outdoor sows using the n-alkanes technique

In recent years there has been a notable increase in outdoor pig production systems; however, the nutritional requirements of these animals have not been well established. To make nutritional decisions relating to the needs of grazing animals, accurate estimations of the herbage intake and value have to be made. N-alkanes found in the wax cuticle of plants have been used as markers to measure the intake of grass by grazing ruminants (Dove and Mayes, 1991). This experiment studied the use of the methodology in grazing pigs.The intake and the digestibility of grass, and the effect of level of supplementary concentrate feed, were measured in late spring and late summer in two studies each with eight multiparous, pregnant sows. In the Spring study sows were nose rung to prevent rooting, but only unrung sows were available for the Summer study.

Serum Leptin Does Not Predict Body Fat Mass in the Very Low Birthweight Infant 1546

Leptin is a hormone produced by adipocytes that regulates body weight and has been found to correlate with the percentage of body fat in children and adults. In addition, leptin is also produced by the placenta and a positive correlation between cord blood leptin levels and birthweight suggests a role for leptin as a fetal growth factor. In the premature infant several studies have demonstrated a higher accretion of body fat when compared to fetuses of the same post-conceptual age and accurate measures of body fat might be useful in guiding nutritional decisions in this population. In this initial study we therefore set out to examine leptin levels in the very low birthweight infant and correlate with other measures of body fat including skinfold measurements and dual energy x-ray absorptiometry (DEXA). Four infants with a mean birthweight of 890 grams and gestational age of 27.7 weeks were studied. Infants were greater than 1 week of age and initiating feeds at enrollment and underwent weekly anthropometric measurements in addition to serum leptin levels until discharge or back transport. All infants manifested adequate weight gain and linear growth as well as increases in skinfold thickness suggesting deposition of subcutaneous fat. In addition, one infant underwent DEXA evaluation revealing 7.3% body fat at one month of age which increased to 9.3% at seven weeks of age. However, no serum leptin was detected in this infant at the time of the DEXA measurements. Suprisingly only one of the four infants had detectable serum leptin with a mean level of.19 ng/ml utilizing an ultrasensitive RIA. We conclude that serum leptin as it is currently measured is not useful to predict body fat mass in the very low birthweight infant. We further speculate that the lack of detectable leptin may be important in altering the extrauterine accretion of body fat in the prematurely born infant.

Computerized Patient Record: Are we Prepared for our Future Practice?

Objective To survey members of The American Dietetic Association (ADA) regarding care documentation systems, computerization of patient care records, and factors to be considered in developing a documentation system compatible with a computer-based patient record. Design The survey instrument was developed in conjunction with a survey consultant/statistician, then mailed to the study sample. Subjects/setting The sample of 500 was drawn from three ADA dietetic practice groups expected to include a high percentage of clinical practitioners. Statistical analysis performed Basic frequency displays were used on all questionnaire items. Pearson correlation coefficients were used among numeric variables, and one-way analysis of variance was used for categoric variables with quantitative variables. Results A total of 171 usable surveys were returned (34%), primarily from dietitians working in an acute-care inpatient environment. The SOAP format (subjective, objective, assessment, and plan) was used by 60% of respondents to document nutrition assessments, although a number of other documentation formats were reported. Most commonly used data in nutrition decision making were medical diagnosis, diet order, anthropometric data, and laboratory values. Most commonly used outcomes measures included laboratory values, tolerance of the nutrition regimen, weight changes, and intake changes. Only 15% of respondents reported that they currently used a computerized patient record. Ninety-three percent of respondents favored standardized nutrition diagnoses, and 95% believed standardized nutrition interventions would prove useful. Applications/conclusions We recommend that dietitians evaluate, standardize, and streamline their documentation to prepare for implementation of computerized systems. The diagnoses and interventions presented in this study could be a starting point. J Am DietAssoc. 1997;97:1099–1104.

A multi-level analysis of feeding behaviour: the geometry of nutritional decisions

We have presented and tested in experiments with insects a new framework which integrates functional, mechanistic, ontogenetic and comparative aspects of nutrition. The framework firstly identifies local optim a (nutritional, intake and growth ‘targets’) within a multi-dimensional nutritional space, where each functionally relevant nutrient forms a single dimension. The positions of these targets are located experimentally through studies of feeding behaviour and physiology and their functional significance is tested using independent performance criteria. Functional rules employed by animals to either reach these targets or, if that is not possible, find a point of best compromise, are then investigated by reference to the geometry of arrays of intake and growth across a range of foods. Changes in the position of the targets with ontogeny are considered, as are the nature of underlying homeostatic mechanisms. We also show how comparative analyses of a range of species can be used to investigate the influence of non-nutritional, ecological factors on the location of the targets.

Pediatricians Do Matter

To the Editor.— The American Academy of Pediatrics expressed concern when the Mead Johnson Division of Bristol-Myers began a direct advertising campaign to sell their Gerber brand infant formula. The Academy believed that pediatricians should counsel parents about infant nutrition and choice of formula, and these important nutritional decisions should not be made in response to advertising on television or in the print media. Marketing surveys validate the concerns of the Academy. The most recent A.C. Nielsen survey (October 22, 1991) indicates that only 56% of the Gerber infant formula that currently is purchased by customers is iron-fortified, as contrasted with 88.2% for SMA, 82% for Similac, and 81.6% for Enfamil.

Aiding Consumer Nutrition Decisions with the Simple Graphic Label Format

This article reports results of research replicating and extending Mohr, Wyse, and Hansen (1980). Mohr et al. found that the quality of consumer nutrition decisions was significantly higher with the graphic nutrient density label format than with the current label format. The present study replicates this finding and, more im portant, demonstrates that the same effect can be produced merely by present ing consumers with a simple graphic label format. Policymakers may wish to con sider the simple graphic label format as a substitute for the graphic nutrient den sity format recently proposed as a replacement for the current label format.

Aiding Consumer Nutrition Decisions: Comparison of a Graphical Nutrient Density Labeling Format with the Current Food Labeling System

Providing consumers with usable nutrition information requires an effective labeling for mat. This study involved consumers in a supermarket setting. Our objective was to determine whether they could, without previous instruction, make as effective nutrition decisions when using a graphic format based on nutrient density as when using the current labeling format.The questionnaire completed by each participating consumer included items regarding demographic data and shopping preferences, and questions evaluating nutrition knowledge and the ability of the shopper to utilize two nutrition labeling formats in making nutrition decisions. Six supermarkets were selected from one large Utah chain as sites for the survey.The nutrient density format produced the greatest percentage of correct responses. The dif ference was particularly evident when our data were analyzed for overall correct responses. Participants who were high school graduates or had family incomes between $4,000–$7,999 made more correct responses when utilizing the nutrient density format than when confronted with the other format. The nutrient density presentation also took less time for participants to complete. The graphical nutrient density format evaluated in our study is more effective than the current labeling format in assisting consumers to make valid nutritional decisions.

On the Fitness of Behavior Sequences

Our aim is to demonstrate a method of determining the extent to which behavior maximizes fitness. We believe the temporal organization of behavior to be in part dependent on the animal's genetic makeup and subject to natural selection and that behavioral strategies may be as adaptive as structural characters. The question of the adaptiveness of behavior has been found hard to study in the past (Tinbergen 1963) because of the difficulty of quantitative verification of hypotheses. The method presented here tests specifically whether deployment of behavioral options is optimally related to environmental conditions.