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Voluntary Food Intake (voluntary + food_intake)
Selected AbstractsDo endogenous seasonal cycles of food intake influence foraging behaviour and intake by grazing sheep?FUNCTIONAL ECOLOGY, Issue 5 2000G. R. Iason Abstract 1.,Large herbivores living in temperate regions show different degrees of seasonal biological variation, including voluntary food intake (VFI). The decline of VFI in winter has been hypothesized to be an evolved response to lower food availability or quality, which can act as an internal constraint on food intake. 2.,The hypotheses were tested that (i) animals that have a greater inherent seasonal variation of VFI, measured indoors under ad libitum conditions, would also have a greater seasonal variation in intake and grazing behaviour under field conditions, and (ii) greater seasonal variation in intake and grazing behaviour under field conditions would be expressed at a higher level of food availability. 3.,The intake and grazing behaviour in summer and winter, of three breeds of sheep, were compared at two levels of food availability (at pasture heights of 3ˇ7 and 5ˇ4 cm). The breeds were known to have contrasting degrees of seasonal variation in food intake when fed ad libitum; the VFI of the Shetland (SH) and Scottish Blackface (BF) sheep varies greatly between seasons whereas that of the Dorset Horn (DH) is less seasonally variable. 4.,All three breeds consistently increased their rates of biting and duration of grazing activity in the winter, taking many more smaller bites each day than in the summer, and both digestibility and intake were lower in winter than in summer. 5.,Contrary to expectation, the DH ewes had the highest seasonal difference of dry matter intake at pasture, whereas the SH breed had the lowest variation of intake between seasons. 6.,This experiment provides no evidence that differences between seasons in intake and foraging behaviour in the field vary with the animals' degree of endogenous seasonal variation in VFI. Variation between seasons was consistent at both levels of resource availability, suggesting that it resulted from seasonal changes in food quality (digestibility) rather than biomass availability. It is not easy to extrapolate from laboratory feeding studies, where animals' own physiological constraints apply, to foraging ecology in the field, where constraints imposed by the environment may be more important. [source] A randomised, controlled trial of the effects of an energy-dense supplement on energy intake, appetite and blood lipids in malnourished community-based elderly patientsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2008G.P. Hubbard Background:, Disease-related malnutrition is common in the elderly and if left untreated may have severe consequences (Stratton & Elia, 2003). One of the strategies used to combat malnutrition is the use of high-energy, low-volume [18.8 kJ mL,1 (4.5 kcal ml,1)] nutritional supplements. This study aimed to investigate the effects of an energy dense supplement on energy intake, appetite and blood lipids in elderly patients at risk of malnutrition. Methods:, In this randomised, controlled, parallel study, 42 community-based patients (mean (SD) age: 84 (7.0) years, mean body mass index (BMI): 20.9 (3.5) kg m,2), identified as being at medium or high risk of malnutrition [Malnutrition Universal Screening Tool (MUST) (Elia, 2003)] were randomised (using standard randomisation methods) to receive either; (i) 1674 kJ day,1 (400 kcal day,1) (in 3 × 30 mL doses) of an energy-dense supplement (Calogen, NutriciaŽ) (n = 19) or (ii) dietary advice in the form of a standardised dietary advice sheet (n = 23), for 4 weeks. Energy intake, appetite, blood lipids [i.e. total cholesterol, low density lipoprotein (LDL) cholesterol (subset analysis only)], body weight, gastro-intestinal tolerance, product compliance and product acceptability were assessed during the 4 week study. Results are presented as mean (SD). Paired t -test and one way anova statistical analyses were undertaken using SPSS v15. Ethical approval for this study was obtained from the appropriate committee. Results:, Supplementation with the energy dense supplement significantly increased mean total daily energy intake by +1736 kJ (+415 kcal, P = 0.009) from 6456 (2330) kJ [1543 (557) kcal] to 8192 (1477) kJ [1958 (353) kcal], with no significant effect on voluntary food intake or appetite scores (for hunger, fullness and desire to eat). In the dietary advice group, although mean total daily energy intake was also significantly increased by +1105 kJ (+264 kcal, P = 0.026) from 5623 (2107) kJ [1344 (503) kcal] to 6728 (2029) kJ [1608 (485) kcal], it was significantly lower than in the energy dense group [-1464 kJ (-350 kcal), P = 0.012] at week 4. Both energy-dense and dietary advice groups maintained weight during the study. No significant adverse effects on blood lipid concentrations were observed in either group, with a significant decrease in total cholesterol concentrations [from 4.26 (1.0) mM to 3.96 (0.8) mM, P = 0.03] and LDL cholesterol concentrations [from 2.32 (0.6) mM to 2.06 (0.5) mM, P = 0.03] in the energy dense group (subset analysis, n = 9). Both supplementation with energy dense supplement and dietary advice were well tolerated with no gastro-intestinal side effects. The energy dense supplement was well accepted with >80% of patients rating it as pleasant and convenient, with an enjoyable taste. Compliance with the energy dense supplement was high, with 95% of patients consuming the recommended dose of 3 × 30 mL throughout the study. Discussion:, This study in elderly patients with or at risk of malnutrition suggests that the energy dense supplement is effective in significantly improving total intakes of energy with no suppression of appetite or voluntary dietary intake, enabling patients to maintain weight and that the energy dense supplement is well tolerated and accepted, with excellent compliance and no adverse effects on blood lipids. Conclusions:, This randomised controlled trial suggests that an energy-dense supplement is an effective, well tolerated and safe method of providing energy supplementation for the management of elderly patients with or at risk of malnutrition in clinical practice. References, Elia, M. (2003) The "MUST" report. Nutritional screening for adults: a multidisciplinary responsibility. Redditch, UK: BAPEN. Available at http://www.bapen.org.uk (accessed on 15 March 2008). Stratton, R.J., Green, C.J. & Elia, M. (2003) Disease-related malnutrition: an evidence-based approach. Oxford: CABI publishing. [source] The relationship between forage cell wall content and voluntary food intake in mammalian herbivoresMAMMAL REVIEW, Issue 3 2010Kerstin MEYER ABSTRACT 1It is generally assumed that animals compensate for a declining diet quality with increasing food intake. Differences in the response to decreasing forage quality in herbivores have been postulated particularly between cattle (ruminants) and horses (hindgut fermenters). However, empirical tests for both assumptions in herbivorous mammals are rare. 2We collected data on voluntary food intake in mammals on forage-only diets and related this to dietary neutral detergent fibre (NDF) content, assuming a nonlinear correlation between these measurements. Generally, the paucity of corresponding data is striking. 3Elephants and pandas showed very high food intakes that appeared unrelated to dietary fibre content. Only in small rodents, and possibly in rabbits, was an increase in food intake on forages of higher NDF content evident. In particular, other large herbivores, including horses, followed patterns of decreasing intake with increasing forage NDF, also observed in domestic cattle or sheep. 4For large herbivores, empirical data therefore do not , so far , support the notion that intake is increased in response to declining diet quality. However, data are in accord with the assumption that most large herbivores have an anticipatory strategy of acquiring body reserves when high-quality forage is available, and reducing food intake (and potentially metabolic losses) when only low-quality forage is available. 5Intake studies in which the influence of digestive strategy on food intake capacity is tested should be designed as long-term studies that outlast an anticipatory strategy and force animals to ingest as much as possible. 6We suggest that a colonic separation mechanism coupled with coprophagy, in order to minimize metabolic faecal losses, is necessary below a body size threshold where an anticipatory strategy (living off body reserves, migration) is not feasible. Future studies aimed at investigating fine-scale differences, for example between equids and bovids, should focus on non-domesticated species. [source] | ||||||||||