Dietary Energy Density Research Articles

Screening Dietary Fat Sources and Concentrations Included in Low- and High-Forage Diets Using an In Vitro Gas Production System

Including dietary fat can increase the energy density of diets fed to ruminants, reducing dry matter intake (DMI). Effects of different fat sources on nutrient digestion and fermentation can vary depending on dietary fat concentration and the forage-to-concentrate ratio (F:C). Therefore, this study’s objective was to screen the effects of fat sources supplemented at different concentrations to high- and low-forage diets on in vitro digestibility and fermentation. Treatments included either low forage (LF; 35%) or high forage (HF; 70%) with two fat levels (6 or 9% DM) using six different fat sources, plus control. The control diet (CON) had a basal level of fat in the diet (3% fat; 0% fat inclusion), and fat sources were added to attain 6% or 9% dietary fat and consisted of the following: Coconut oil, CO; Poultry fat, PF; Palm oil, PO; Palm kernel oil, PKO; Soybean oil, SOY; and Ca Salts, MEG. In vitro Gas Production (GP) modules were randomly assigned to treatments in a 2 × 2 × 7 factorial design and were incubated for four 24 h runs. The CO-fed module had the highest dry matter (DM) apparent digestibility (AD) (p < 0.01), followed by SOY and PF. The true DM digestibility (TDMD) and organic matter (OM) AD were the highest in CO (p < 0.01) than the other fat types. The AD for DM, OM, neutral detergent fiber (NDF), and acid detergent fiber (ADF) was higher in LF (p < 0.01). The 6% fat inclusion had a higher GP (109 vs. 103 mL ± 2.09; p < 0.03). Total volatile fatty acid (VFA) concentration was lower in different fat types than the CON and the acetate molar proportion (p > 0.01). The propionate was the lowest for the CON, which increased the acetate to propionate (A:P) ratio (p < 0.01). These results suggest that LF diets with high fat concentrations can be utilized, and different fat sources may improve DM and fiber digestibility.

Interactive effects of dietary energy levels with amino acid density on growth performance and optimal digestible Lys to energy ratio of male broiler chickens

A total of 2,400 day-old off-sex male Ross 308 chicks were used in a 4 × 3 factorial array (8 replicates with 25 birds per replicate) to determine the interactive effects of dietary metabolizable energy (ME) and amino acid (AA) densities on productive traits of broiler chickens reared to 42 d of age. The experimental factors were 4 ME levels (control, -50, -100, -150 kcal) and 3 digestible AA levels (control, +3.0 and +6.0%). Diets were fed for starter (0-10 d), grower (11-24 d), finisher (25-35 d), and withdrawal (36-42 d) phases, with consistent reduction of ME and increase in AA density for each phase. Overall, ME reduction did not compromise final body weight (BW; d 42). However, when ME was reduced by 50 kcal, only the diets with +6% AA density improved BW, resulting in an interaction between ME and AA levels (P < 0.05). Reducing ME and increasing AA densities independently increased total feed intake (P < 0.01). An interaction between ME and AA density on feed conversion ratio (FCR) was observed where increasing AA density at both +3.0 and +6.0% levels at control ME reduced FCR, but with reduced ME diets, FCR was reduced only at +6% AA density (P < 0.01). Quadratic broken line models estimated a digestible Lys to ME ratio (mg Lys/1,000 kcal ME) of 474 and 407 in starter and grower diets, respectively, to optimize both BW and FCR. However, in finisher phase a ratio of 363 could only be predicted for optimal FCR and in withdrawal a ratio of 349 to optimize BW. In summary, these results indicate that the interaction between ME and AA densities affects the productive traits of broiler chickens. Increasing AA density at control ME density improves FCR, while reduced ME diets require higher AA density to improve FCR. Quadratic broken line models suggest specific digestible Lys to ME ratios for optimizing BW and FCR across different phases of the production cycle.

IL-22 resolves MASLD via enterocyte STAT3 restoration of diet-perturbed intestinal homeostasis

The exponential rise in metabolic dysfunction-associated steatotic liver disease (MASLD) parallels the ever-increasing consumption of energy-dense diets, underscoring the need for effective MASLD-resolving drugs. MASLD pathogenesis is linked to obesity, diabetes, "gut-liver axis" alterations, and defective interleukin-22 (IL-22) signaling. Although barrier-protective IL-22 blunts diet-induced metabolic alterations, inhibits lipid intake, and reverses microbial dysbiosis, obesogenic diets rapidly suppress its production by small intestine-localized innate lymphocytes. This results in STAT3 inhibition in intestinal epithelial cells (IECs) and expansion of the absorptive enterocyte compartment. These MASLD-sustaining aberrations were reversed by administration of recombinant IL-22, which resolved hepatosteatosis, inflammation, fibrosis, and insulin resistance. Exogenous IL-22 exerted its therapeutic effects through its IEC receptor, rather than hepatocytes, activating STAT3 and inhibiting WNT-β-catenin signaling to shrink the absorptive enterocyte compartment. By reversing diet-reinforced macronutrient absorption, the main source of liver lipids, IL-22 signaling restoration represents a potentially effective interception of dietary obesity and MASLD.

Prospective associations between an empirically derived dietary pattern and life satisfaction in Malaysian adolescents

BackgroundLittle is known on the prospective associations between an empirically derived dietary pattern (DP) and life satisfaction among adolescents. This PUTRA-Adol follow-up study aimed to assess the prospective associations between the empirically derived DP and life satisfaction during adolescence.MethodsA total of 585 and 262 adolescents participated in the baseline PUTRA-Adol study in 2016 and PUTRA-Adol follow-up study in 2019–2020, respectively. These adolescents were recruited from three southern states in peninsular Malaysia, namely Negeri Sembilan, Melaka and Johor. Dietary assessments were estimated using a validated food frequency questionnaire (FFQ) while a Multidimensional Students’ Life Satisfaction Scale (MSLSS) was used to measure life satisfaction at baseline in 2016 as well as at follow-up in 2019–2020. A DP characterised by foods high in free sugar and energy dense was identified using reduced rank regression (RRR), cross-sectionally at baseline and was reported elsewhere. Similar RRR analysis was used to find a DP that best explained the variation in response variables linked to poorer life satisfaction, including dietary energy density (DED), fiber density, and percentage of energy from total fat and sugar at the PUTRA-Adol follow-up study. Prospective relationship between adherence to the identified DPs and overall life satisfaction scores as well as its domains between 2016 and 2019–2020 were evaluated using generalized estimating equation models (GEE).ResultsA DP characterized by high intakes of percentage energy from sugar, fibre and low in DED and percentage energy from total fat was identified at the 2019–2020 follow-up. The identified DP explained 11% of total variations in the response variables and was characterized by high intakes of sweets, sugar sweetened beverages (SSB) and fruits. Female adolescents [67.6(8.9)] had a mean (SD) of life satisfaction that was higher than male adolescents [67.5(10.8)] p < 0.05 in 2019–2020. Prospective analysis found a significant positive association between the identified DP and school domain, in male adolescents (β = 0.117; 95% CI 0.001, 0.234) and an inverse relationship between the DP z-score and self-domain in all adolescents (β = − 0.060; 95% CI − 0.115, − 0.005) from 2016 to 2019–2020.ConclusionsAn increasing score for the predominant ‘High sugar and High fibre’ DP was prospectively associated with increasing life satisfaction score for the school domain in male adolescents and decreasing score for self-domain in both male and females during adolescence. A lifestyle intervention targeting reduced dietary intakes, particularly sugar, may improve life satisfaction in adolescents and promote healthier future without compromising dietary intakes for chronic disease prevention later in life.

Effects of rumen-protected fat on performance, carcass and meat characteristics, and feeding behaviour of Nellore bulls finished in intensive grazing systems

Context Beef cattle production in the tropics is based on the grazing system. Concentrate supplementation has a significant influence on carcass gain and meat quality. Additionally, the inclusion of some lipid feedstuffs, such as rumen-protected fat (RPF), can increase the net energy for weight gain, and be an alternative to increase the productive performance and carcass traits of grazing beef cattle. Aims This study evaluated the effects of RPF on performance, carcass traits and feeding behaviour of Nellore bulls in an intensive grazing system during the rainy season. Methods Twenty-four Nellore bulls (initial bodyweight of 454.0 ± 46.1 kg) were used in a randomised completed block design, based on initial bodyweight. The animals were distributed in 12 paddocks (two bulls per paddock) in a continuous grazing system and randomly assigned to one of two treatments: control (n = 6), a concentrate without added protected fat provided ad libitum, and RPF (n = 6), a concentrate with the addition of 3% protected fat (Nutricorp, Araras, São Paulo, Brazil) provided ad libitum. Statistical analysis was performed using the MIXED procedure of SAS 9.4 with paddock as the experimental unit (12 paddocks). The principal model included fixed effect of treatment and block as a random effect. For forage characteristics, the experimental period was a considered fixed effect. The study lasted 105 days, and was divided into four periods. At the end of each period, forage collections were performed, bulls were weighed and feeding behaviour was recorded. After 105 days, the bulls were slaughtered in a commercial slaughterhouse, and three 2.54-cm Longissimus dorsi steaks of each animal were collected to evaluate the colour, the chemical and physical composition, and the sensory analysis of the meat. Keys results The inclusion of RPF in the concentrate did not affect (P &gt; 0.05) the final bodyweight, average daily gain, concentrate intake and feed efficiency, but there was a tendency (P &lt; 0.07) for higher carcass weight for the bulls that received RPF. Bulls supplemented with RPF had a greater (P &lt; 0.05) average carcass gain. For meat quality, an effect (P &lt; 0.01) was observed for hue (25.32 and 27.91 for control and RPF, respectively). Conclusions The addition of 3% RPF in the concentrate ration has the potential to improve carcass traits and meat quality of beef cattle in an intensive pasture finishing system. Implications The inclusion of RPF will increase dietary energy density of grazing beef cattle with a tendency to increase carcass gain. This can be an opportunity to increase the production per animal and income of farmers.

Social Support, Diet, and Physical Activity among Latina/Hispanic Women Breast Cancer Survivors.

Diet and physical activity guidelines for cancer survivorship are less likely to be followed by populations of minority cancer survivors, such as Latina/Hispanic women, compared to non-Hispanic White women. It is important to understand psychosocial mechanisms that may increase adherence to healthy lifestyle habits, especially in populations at risk for poorer cancer outcomes. This cross-sectional study examined the relationships between overall social support (SS) and SS from three sources (family, friends, and significant other) with diet (fruit and vegetables, fat, energy density, and diet quality), and moderate-to-vigorous physical activity (MVPA) behaviors in Latina/Hispanic women with a history of breast cancer (n = 85; M age = 55.2; SD = 9.2). Linear regression models and odds ratios were used to examine associations and adjusted for age, income, and acculturation. Family, significant other, and total SS were positively related to total fruit and vegetable intake but SS from friends was not. Higher levels of SS from all sources were each related to a low energy density diet. A higher quality diet was only related to SS from family. SS was not related to fat intake or MVPA. Higher SS from family and a significant other were associated with higher odds of meeting the fruit/vegetable guidelines; (family, OR = 3.72, 95% CI [1.21, 11.39]; significant other, OR = 3.32, 95% CI [1.08, 10.30]). Having more SS from family or a significant other may contribute to Latina/Hispanic women breast cancer survivors meeting national guidelines for a diet high in fruits and vegetables and low in energy density.

Independent effects of volume and energy density manipulation on energy intake and appetite in healthy adults: A randomized, controlled, crossover study

Consuming enough energy to meet high energy demands can be challenging for military personnel wherein logistical constraints limit food availability. Increasing dietary energy density (ED) and/or volume density (VD) of rations may be countermeasures, but whether positive linear associations between ED and energy intake (EI) hold at moderate-to-high ED and VD is unclear. This study examined the effects of covertly increasing the ED and VD of moderate ED (≥1.6 kcal/g) foods on appetite and energy intake. Twenty healthy men completed four 2-day treatments in random order by consuming a standardized diet containing three experimental food items (EXP) engineered using leavening, physical compression and fat manipulation to be isovolumetric but lower (L) or higher (H) in ED and VD creating four treatments: LED/LVD, LED/HVD, HED/LVD, HED/HVD. Consumption of EXP was compulsory during two meals and a snack, but remaining intake was self-selected (SSF). Results failed to show any ED-by-VD interactions. During LVD, EI was lower for EXP (−417 kcal [95%CI: 432, −402], p < 0.01) and TOTAL (SSF + EXP) (−276 kcal [95%CI: 470, −83], p = 0.01) compared to HVD, while SSF EI did not differ (140 kcal [-51, 332], p = 0.15). During LED, EI for EXP (−291 kcal [95%CI: 306, −276], p < 0.01) was lower than HED, while SSF EI was higher than HED (203 kcal 95%CI: [12, 394], p = 0.04) and TOTAL EI did not differ (−88 kcal [-282, 105], p = 0.36). Thus, when a small isovolumetric portion of the diet was manipulated, increasing the VD of moderate ED foods failed to elicit compensatory reductions in ad libitum EI while increasing the ED of moderate ED foods did. Findings may support VD manipulation of moderate ED foods as a strategy to promote increased short-term EI in environments wherein logistical burden may limit food volume.

Effect of energy level of pullet diet and age on laying performance and expression of hypothalamus-pituitary-gonadal related genes in laying hens

Dietary energy density influences feed intake (FI) and development of layer-type pullets. A total of 384 nine-wk-old Hy-Line Brown pullets were randomly assigned to one of 3 dietary treatments: fed a diet with 2,600, 2,750, and 2,900 Kcal metabolizable energy/kg (ME/kg) from 10 to 21 wk of age. The results showed that the 2,900 and 2,600 ME groups had lower feed and ME intake (P < 0.01) from 10 to 21 wk of age. The 2,600 ME pullets had heavier body weight (BW) and longer shank length (P < 0.05) at 21 wk of age than the 2,750 ME group. The eggshell percentage was increased by the 2,600 and 2,900 kcal/kg treatments (P = 0.002). Serum concentration of 17-β-estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) decreased at 70 wk of age (P < 0.05). Pullet diet and its interaction with age had a significant influence (P < 0.001) on the expression of gonadotropin-releasing hormone 1 (GnRH-1) and gonadotropin-inhibitory hormone (GnIH) in the hypothalamus and of gonadotropin releasing hormone 1 receptor (GnRH-1R) and gonadotropin-inhibitory hormone receptor (GnIHR) in the pituitary. In the hypothalamus, GnRH-1 expression increased from 9 to 40 wk of age and then decreased; however, GnIH expression was highest at 70 wk of age. Follicle-stimulating hormone receptor (FSHR) expression increased (P < 0.001) at wk 40 and decreased at wk 70 compared to wk 21 at various follicular stages. In conclusion, the energy level of pullet diet had no unfavorable influence on feed intake, laying rate, egg mass, and FCR, whereas change egg weight and mortality during the laying period from 21 to 70 wk of age. during the laying period. These results suggest that pullet dietary energy can activate the expression of genes related to reproduction in the hypothalamus, whereas it plays a minor role in the regulation of genes in the pituitary and ovary. Age-induced gene expression in the hypothalamus-pituitary-gonadal (HPG) axis is associated with laying performance in hens.

A pilot study of the contribution of energy-dense Caribbean diets to acrylamide exposure with associated health risks for a population of university students in Trinidad and Tobago

Previous studies on university students have indicated a significant decline in the consumption of fruits and vegetables complemented by an increase in energy-dense foods. The food toxicant, acrylamide, typically occurs in carbohydrate-rich, energy-dense foods that have been heated. Hence, this work presents an estimated dietary acrylamide exposure for university students in Trinidad and Tobago. A 2-day dietary recall method was used to obtain the food consumption information from 683 university students of differing sociodemographic backgrounds. The acrylamide exposure was estimated using a deterministic approach. The median acrylamide intake was estimated to be 1.39 µg/kg bw/day. The estimated mean acrylamide dietary intakes for the female and male population were 1.40 and 1.37 µg/kg bw/day, respectively. Coffee was determined to be the major dietary contributor to acrylamide exposure. However, bread was the food item that was most frequently consumed among the students. Using multiple linear regression, a possible correlation was detected between the acrylamide exposure and these variables: dietary habits (mostly eat out; p < 0.05), and Indian ethnicity (p < 0.10). Using the margin of exposure approach, dietary acrylamide exposure was found to be a health concern with regards to neurotoxicity and carcinogenicity. An evaluation of the procedures and results from this pilot study was carried out for the potential of conducting a full-scale research project.

Effects of Cattle Breeds and Dietary Energy Density on Intake, Growth, Carcass, and Meat Quality under Thai Feedlot Management System.

This study determines the effects of varying dietary metabolizable energy densities on Holstein Friesian and Charolais crossbred beef cattle in fattening phases. The research focuses on nutrient utilization, ruminal fermentation, growth performance, carcass traits, and meat quality. Thirty-six steers were used in the feeding trial that lasted for six months according to a 2 × 3 factorial arrangement in a randomized complete block design (Factor A, cattle breeds (Holstein Frisian, Charolais crossbred); B, metabolizable energy density (10.5, 11.1 and 11.8 MJ/kg DM)) with six replications. The dietary energy density had no interaction with the cattle breeds (p > 0.05). Despite fewer carcass yields, Holstein Friesian crossbreds indicate superior eating quality to Charolais crossbreds on drip loss, meat iron content, and Warner-Bratzler shear force due to increased intramuscular fat content (p < 0.05) with similar meat color (p > 0.05). Increased dietary energy density positively impacts nutrient and energy intake and rumen fermentation (p < 0.05) but did not affect growth and carcass traits (p > 0.05). This research suggests the potential of Holstein Friesian crossbreds for intensive beef production, providing valuable insights into optimal feeding strategies for achieving quality meat outcomes. On-farm feeding trials are needed to develop a practical and economical Thai beef feedlot management system.

Evaluate Cardiopulmonary markers, oxidative stress and inflammatory markers among healthy people with and without a history of type 2 diabetes

Introduction: Type 2 diabetes mellitus (T2DM) accounts for around 90% of all cases of diabetes. In T2DM, the response to insulin is diminished, and this is defined as insulin resistance. During this state, insulin is ineffective and is initially countered by an increase in insulin production to maintain glucose homeostasis, but over time, insulin production decreases, resulting in T2DM. T2DM is most commonly seen in persons older than 45 years. Still, it is increasingly seen in children, adolescents, and younger adults due to rising levels of obesity, physical inactivity, and energy-dense diets. This is a Prospective, Cross sectional, Randomization, Observational study was conducted in the Department of Biochemistry and Medicine, Index Medical College. Inclusion Criteria: Controls without family history of type 2 diabetes: Healthy subjects in the age group of 18 - 30 years of either Gender. Cases with family history of type 2 diabetes either gender age group of 18 - 30 years of Age. Individuals who are using any medicines for any health condition to restrict in performing submaximal exercise. Total cholesterol (TC) in 18-21 years in Case Group showed an increase in Mean 209.34 + 14.85 mg/dl then control group 163.26 + 23.81 mg/dl (p=0.001), also Total cholesterol (TC) in 22-25 years in Case Group showed an increase in Mean 211.29 + 16.61 mg/dl then control group 177.42 + 27.98 mg/dl (p=0.001). HDL in 18-21 years in Case Group showed a decrease in Mean 39.35 +5.56 mg/dl then control group 40.87 + 6.20 mg/dl (p=0.167), too HDL in 22-25 years in Case Group showed a decrease in Mean 40.87 +6.22 mg/dl then control group 43.97 + 6.93 mg/dl (p=0.173). Triglycerides (TGL) in 18-21 years in Case Group showed an increase in Mean 144.07 + 9.96 mg/dl then control group 123.44 + 18.87 mg/dl (p&lt;0.0001), in addition Triglycerides (TGL) in 22-25 years in Case Group showed an increase in Mean 147.48 + 16.70 mg/dl then control group 130.08 + 20.03 mg/dl (p=0.0147). LDL in 18-21 years in Case Group showed an increase in Mean 141.60 + 16.24 mg/dl then control group 97.71 + 16.87 mg/dl (p=0.650), similar LDL in 22-25 years in Case Group showed an increase in Mean 140.92 + 18.80 mg/dl then control group 107.43 + 19.54 mg/dl (p=0.841). VLDL in 1-21 years in Case Group showed an increase in Mean 28.74 + 2.02 mg/dl then control group 24.68 + 3.77 mg/dl (p&lt;0.0001), moreover VLDL in 22-25 years in Case Group showed an increase in Mean 29.49 + 3.34 mg/dl then control group 26.02 + 4.01 mg/dl.

Effect of supplementation of bioactive rich tree leaves on nutrient utilization, growth performance, methane emission and fatty acid profile in finisher lambs fed energy dense diet

To study the effect of supplementing bioactive rich tree foliages in energy dense diet on lamb production and tissue fatty acid profile, 24 weaner male lambs (∼90days old) were divided equally into 2 groups and fed complete feed blocks without (C) and with 6% Hardwickia binata (anjan tree) leaves (T). Feed blocks in both the groups consisted of 3.25% rumen bypass fat. Dry matter intake and plane of nutrition were comparable among the groups but digestibility of neutral and acid detergent fibre were lower (P<0.05) in T than C. Rumen fermentation attributes revealed higher (P<0.05) concentration and proportion of propionic acid and total volatile fatty acids in T compared to C. The metagenomic equivalent values of total methanogens and protozoa were lower (P<0.05) while, population of Butyrivibrio fibrisolvens was higher in T compared to C. Loss of metabolizable energy through methane was reduced by 4.6 percentage points in T than C which resulted in higher microbial nitrogen synthesis in T from methane mitigation. Subsequently, the average daily gain in lambs was improved by 5.9% in T compared to C. The fatty acid profile of Longissimus thoracis muscle revealed higher (P<0.05) C18:2c9t11 content in lambs of T group than C. Hence, from the present findings it can be concluded that inclusion of Hardwickia binata leaves at 6% level increased condensed and hydrolysable tannin content of the diet which modestly affected rumen fermentation resulting in reduced methane production and enhanced conjugated linoleic acid content in muscle tissue.

Abstract 760: Alteration to transcriptional rhythmicity in mammary glands from pubertal MMTV-PyMT mice fed a high-fat diet

Abstract Biological clocks, existing in all human organ systems, cycle every 24 hours in a diurnal pattern and control the daily rhythms of human life (e.g., eating vs. fasting, sleep vs. wakefulness), which is essential for health and wellbeing. Disruption of the biological clocks, either by genetic or environmental alteration, disturbs circadian rhythms, which may lead to chronic diseases. Childhood obesity is a risk factor for breast cancer in adult women. Lifestyle changes in the modern world (e.g., energy-dense diets) serve as environmental factors that contribute to alterations in biological clocks and obesity. The present study examined transcriptional rhythmic changes in mammary glands from pubertal MMTV-PyMT mice fed a high-fat diet (HFD). Three-week-old female mice (FVB background) were randomly assigned into three groups - wild-type (WT) mice fed the AIN93G diet and MMTV-PyMT mice fed the AIN93G diet or an HFD for three weeks. At the end of the study, mammary glands were collected every 4 hours over a period of 24 hours (Zeitgeber time 0-24 hours) for RNA-sequencing analysis. The mammary weight was 0.45±0.02, 0.59±0.02, and 0.67±0.02 g for WT mice fed the AIN93G diet and MMTV-PyMT mice fed the AIN93G and HFD, respectively (means ± SEM, all p&amp;lt;0.05 when three groups were compared each other). The rhythmicity analysis using R showed that greater than 1,000 transcripts were classified as “loss of rhythm” when MMTV-PyMT mice (both AIN93G-fed and HFD-fed groups) were compared to WT mice fed the AIN93G diet. Eighteen transcripts were classified as “loss of rhythm” in MMTV-PyMT mice when the HFD was compared to AIN93G diet. Hierarchical clustering analysis showed differentially expressed genes that were significantly altered and KEGG enrichment analysis showed the most upregulated and downregulated metabolic pathways in treatment groups than in the control group at each time point over the 24-hour period. These findings indicates that genetic alterations may have a greater effect than dietary effects on transcriptional rhythmicity in mammary glands from pubertal mice. Citation Format: Lin Yan, Daniel G. Palmer, Huawei Zeng. Alteration to transcriptional rhythmicity in mammary glands from pubertal MMTV-PyMT mice fed a high-fat diet [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 760.

Relationship between intake of energy-dense diets and nutritional status of adolescents in primary schools in Nairobi City County, Kenya

Background: Energy-dense diets are of low nutrient quality but high energy content and this may have adverse health outcomes, especially in adolescence where the body is transforming from childhood to adulthood. Intake of energy-dense diets is associated with various forms of malnutrition including obesity, overweight, underweight and other micronutrient deficiencies. There is however scanty information about the relationship between the intake of energy-dense foods and adolescents' nutritional status. Aims: This study aimed to establish the relationship between intake of energy-dense diets and the nutritional status of adolescents in Nairobi County. Subjects and Methods: The study was a cross-sectional descriptive research design involving quantitative techniques of data collection. A total of 161 adolescents, 87 females and 74 male aged 10-14 years participated in the study. Cluster sampling was used to select schools in Embakasi South Sub- County. Simple random sampling was used to select adolescents in classes 5, 6 and 7. Data were collected using structured questionnaires, 7-day food frequency questionnaires, and anthropometric measurements. Data analysis was done using; SPSS version 23.0 (quantitative data), ENA for SMART (anthropometric data), Nutrisurvey software (Dietary data) and hypothesis testing (Pearson correlation). Results: The study established a burden of malnutrition among adolescents in Nairobi County (13%) underweight, (5.7%) overweight, (4.3%) severely underweight, and (2.5%) obese. The energy-dense foods which were found to have significant relationship with the nutritional status of the adolescents were: potato chips (r = 0.044, p = 0.045), doughnuts (r = -0.02, p = &lt;0.001), pancakes (r = -0.001, p = 0.762), bhajia (r = -0.014, p = 0.897), cheese (r = -0.107, p-value = 0.660), and Regular soft drink (r = -0.147, p= 0.101. Conclusion: The nutritional status of the adolescents was influenced by the intake of some energy-dense diets and sociodemographic characteristics. Keywords: Food energy-density; dietary intake; undernutrition; overweight; obese; fatty foods.

3 Measuring feed intake in cows

Abstract In recent years, substantial progress has been made in understanding the sources of biological variation and genetic components of feed efficiency in growing animals consuming energy-dense mixed diets during the post-weaning phase. Much less is known about within-animal variation of feed efficiency for beef cows consuming moderate to low-quality forage diets common to most cow/calf production systems. Considerable evidence indicates the existence of a genetic by environment interaction for feed efficiency. Phenotype for feed intake and feed efficiency are most practically and cost effectively determined during the post-weaning growing stage. However, due to the additional nutrient sinks associated with gestation and lactation, and the cost, labor and technology required to measure economically relevant traits in mature cows, little is known about forage utilization efficiency in beef cows. The beef cow/calf segment of the industry represents, by far, the greatest opportunity to reduce beef production input costs and reduce the industry’s carbon footprint. We reason that selection tools for feed intake and feed efficiency developed over the last 20 years are effective for the post-weaning growing and finishing phases, although only marginally effective for beef cows consuming unprocessed, moderate to low-quality forage. In this session, we will discuss challenges, opportunities, and experiences associated with measuring forage intake and recovered energy in beef cows.

The hedonic overdrive model best explains high-fat diet-induced obesity in C57BL/6 mice.

High-fat diets cause obesity in male mice; however, the underlying mechanisms remain controversial. Here, three contrasting ideas were assessed: hedonic overdrive, reverse causality, and passive overconsumption models. A total of 12 groups of 20 individually housed 12-week-old C57BL/6 male mice were exposed to 12 high-fat diets with varying fat content from 40% to 80% (by calories), protein content from 5% to 30%, and carbohydrate content from 8.4% to 40%. Body weight and food intake were monitored for 30 days after 7 days at baseline on a standard low-fat diet. After exposure to the diets, energy intake increased first, and body weight followed later. Intake then declined. The peak energy intake was dependent on both dietary protein and carbohydrate, but not the dietary fat and energy density, whereas the rate of decrease in intake was only related to dietary protein. On high-fat diets, the weight of food intake declined, but despite this average reduction of 14.4 g in food intake, they consumed, on average, 357 kJ more energy than at baseline. The hedonic overdrive model fit the data best. The other two models were not supported.

Dietary fat and high energy density diet: Influence on intestinal health, oxidative stressand performance of weaned piglets.

The utilization of dietary components to support gut function and the health of young animals is an important factor for improved performance. The influence of high dietary fat levels in a lowor high energy density diet on the performance of weaned piglets in relation to intestinal absorptive function, amino acid utilization, oxidative stress, and microbial metabolites was assessed in this study. The study examined the effect of two different diets containing either a low energy density/high-fat level or a high energy density/high-fat level. A total of 16 healthy weaners (9.60 ± 0.13 kg) were allocated to one of the two dietary treatments. There were eight weaners per treatment. Results showed that feed intake and body weight gain of weaners were increased by the diet of high energy density/high-fat level (p < 0.05), but the feed efficiency showed an increased tendency of significance (p = 0.05). In the duodenum, the villus height(VH) and VH/crypt depth (CD) ratio (VH:CD) were increased by dietary high energy density/high fat. In the jejunum and ileum, the CD was increased by low energy density/high-fat diet, while the goblet cell count and VH:CD were increased by dietary high energy density/high-fat level. Methionine, lysineand phenylalanine concentrations were increased by high energy density/high-fat diet while low energy density/high-fat diet showed an increased tendency to increase citrulline and ornithine concentrations in the piglet. Oxidative stress marker, lactase enzyme activity and serum calcium concentration were increased by a high energy density/high-fat diet. Increased dietary fat in all diets induced diarrhoea in the weaners (p < 0.01). It was concluded that a dietary high energy density/high-fat diet seems to positively modulate gut absorptive function, serum amino acid (methionine and lysine), calcium levels and increased oxidative stress markers in the weaned piglets.

Dietary Energy Density Is Associated with Biomarkers of Chronic Diseases—A Cross-Sectional Study of School-Aged Children in Rural Mexico

BackgroundDietary energy density (DED) is associated with chronic disease markers in adults. However, results in children are still controversial. ObjectiveTo evaluate the DED of children and its association with obesity and biomarkers of chronic disease. MethodsIn this cross-sectional study, we recruited 284 children (6–10 y) from rural Mexico. Dietary intake was assessed using three 24-h recalls. DED was calculated for “foods only” (DEDfo) and for “foods and beverages” (DEDfb). Weight, height, and body fat percent (dual-energy X-ray absorptiometry) were measured. Inflammatory cytokines, lipid profile, leptin, and insulin resistance were determined from a fasting blood sample. ResultsDEDfo was 1.91 ± 0.36 kcal/g and DEDfb was 1.36 ± 0.31 kcal/g. Higher DEDfo and DEDfb were associated with higher risk to have insulin resistance [odds ratio (OR) = 3.92, 95% confidence interval (CI): 1.66, 9.22, P < 0.01; OR = 3.51, 95% CI: 1.25, 9.87, P = 0.02, respectively]. Higher DEDfo was associated with higher risk of higher leptin levels (OR = 3.17, 95% CI: 1.01, 10.23). Also, DEDfo and DEDfb were associated with higher concentrations of cholesterol (β = 11.67, 95% CI: 1.81, 19.53, P = 0.03; and β = 11.74, 95% CI: 2.69, 20.74 P = 0.01, respectively) and higher odds of having high insulin concentrations (OR = 2.52, 95% CI: 1.26, 5.06, P = 0.01; and OR = 2.95, 95% CI: 1.30, 6.70, P = 0.01). DEDfo and DEDfb were not associated with any measure of obesity and inflammatory cytokines in the adjusted models. ConclusionsDED was associated with higher leptin and cholesterol concentrations, and having insulin resistance, but not with any measure of obesity or inflammation. Reducing DED may reduce risk of cardiovascular disease and improve insulin sensitivity in school-aged children.

Time-restricted feeding restores metabolic flexibility in adult mice with excess adiposity.

Obesity is prevalent with the adult population in the United States. Energy-dense diets and erratic eating behavior contribute to obesity. Time-restricted eating is a dietary strategy in humans that has been advanced to reduce the propensity for obesity. We hypothesized that time-restricted feeding (TRF) would improve metabolic flexibility and normalize metabolic function in adult mice with established excess adiposity. Male C57BL/6NHsd mice were initially fed a high-fat diet (HFD) for 12 weeks to establish excess body adiposity, while control mice were fed a normal diet. Then, the HFD-fed mice were assigned to two groups, either ad libitum HFD or TRF of the HFD in the dark phase (12 h) for another 12 weeks. Energy intake and body fat mass were similar in TRF and HFD-fed mice. TRF restored rhythmic oscillations of respiratory exchange ratio (RER), which had been flattened by the HFD, with greater RER amplitude in the dark phase. Insulin sensitivity was improved and plasma cholesterol and hepatic triacylglycerol were decreased by TRF. When compared to HFD, TRF decreased transcription of circadian genes Per1 and Per2 and genes encoding lipid metabolism (Acaca, Fads1, Fads2, Fasn, Scd1, and Srebf1) in liver. Metabolomic analysis showed that TRF created a profile that was distinct from those of mice fed the control diet or HFD, particularly in altered amino acid profiles. These included aminoacyl-tRNA-biosynthesis, glutathione metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis pathways. In conclusion, TRF improved metabolic function in adult mice with excess adiposity. This improvement was not through a reduction in body fat mass but through the restoration of metabolic flexibility.

The effect of reducing dietary energy on performance, intestinal morphology and intestinal peptide and amino acid transporters in broiler chicks

AbstractBackgroundPrevious research has investigated the impact of different factors such as gender and age of birds, protein and amino acid levels, protein origin and the physical form of the diet, on the mRNA expression of intestinal peptides and amino acid transporters. Nevertheless, there have been no attempts to examine the impact of dietary energy density on the mRNA abundance of intestinal amino acid and peptide transporters in humans or animals. This is the first reported case in both humans and animals.ObjectivesThis experiment aimed to evaluate the influence of two levels of metabolizable energy ([ME]; 2950 and 2850 kcal ME/kg diet) on performance and jejunal morphology and mRNA expression of amino acid (B0AT, b0,+AT, CAT1 and y+LAT1) and peptide (PepT1) transporters in broiler chickens during the starter period (0–10 days of age).MethodsTwo hundred and seventy day‐old male Ross 308 broiler chickens were randomly assigned to two dietary treatments with nine replicates and fifteen birds in each replicate. At 10 days of age, the outcome variables were measured, which included the assessment of the mRNA abundance of PepT1, b0,+AT, B0AT, y+LAT1 and CAT1 in the jejunal section using real‐time PCR.ResultsThe findings of this study revealed no significant impact of the dietary treatments on feed intake, body weight gain, feed conversion ratio and the jejunal mRNA abundance of PepT1, CAT1 and y+LAT1 (p &gt; 0.05). However, a reduction in dietary ME level from 2950 to 2850 kcal ME/kg diet resulted in a decrease in the mRNA level of B0AT and b0,+AT (p ≤ 0.05). The reduction in dietary energy level did not lead to any significant changes in villus width, villus height, crypt depth, villus surface area and villus height to crypt depth ratio (p &gt; 0.05).ConclusionThe results demonstrated that decreasing dietary energy density may alter the expression of amino acid transporters in the intestine while having no impact on the growth performance and morphometric structure of the intestine.