Effects of sustained cold and heat stress on energy intake, growth and mitochondrial function of broiler chickens

To study the correlation of broiler chickens with energy intake, growth and mitochondrial function which exposed to sustained cold and heat stress and to find out the comfortable temperature, 288 broiler chickens（21-day with（748±26） g, 144 males and 144 females） were divided randomly into six temperature-controlled chambers. Each chamber contained six cages including eight AA broilers per cage, each cage as a repeat. After acclimation for one week（temperature, 21℃; relative humidity, 60%）, the temperature of each chamber was adjusted（finished within 1 h） respectively to 10, 14, 18, 22, 26, or 30℃（RH, 60%） for a 14-day experimental period. After treatment, gross energy intake（GEI）, metabolizable energy intake（MEI）, the ratio of MEI/BW, metabolizability, average daily gain（ADG）, the concentration of liver mitochondria protein and cytochrome c oxidase（CCO） were measured respectively. Our results confirmed that when the temperature over 26℃ for 14 days, GEI, MEI and CCO activities were decreased significantly（P〈0.05）, but the concentration of liver mitochondria protein was increased and metabolizability of broilers was not influenced（P〉0.05）. Compared with treatment for 14 days, the ratio of MEI/body weight（BW） were also decreased when the temperature over 26℃ after temperature stress for 7 days（P〈0.05）, meanwhile mitochondrial protein concentration was increased at 10℃ and CCO activity was not affected（P〉0.05）. Additionally at 22℃, the ADG reached the maximal value. When kept in uncomfortable temperatures for a long time, the ADG and CCO activities of broiler were reduced, which was accompanied by mitochondrial hyperplasia. In summary, our study focused on the performance of broilers during sustained cold and heat environmental temperatures ranging from 10 to 30℃. From the point of view of energy utilization, moreover, 22 to 26℃ is comfortable for 28–42 day s broilers. And these could provide the theoretical basis on the high efficient production.

A meta-analysis of the effects of energy intake on risk of digestive cancers

AIM:To quantitatively assess the relationship between energy intake and the incidence of digestive cancers in a meta-analysis of cohort studies.METHODS:We searched MEDLINE,EMBASE,Science Citation Index Expanded,and the bibliographies of retrieved articles.Studies were included if they reported relative risks(RRs) and corresponding 95% CIs of digestive cancers with respect to total energy intake.When RRs were not available in the published article,they were computed from the exposure distributions.Data were extracted independently by two investigators and discrepancies were resolved by discussion with a third investigator.We performed fixed-effects meta-analyses and meta-regressions to compute the summary RR for highest versus lowest category of energy intake and for per unit energy intake and digestive cancer incidence by giving each study-specific RR a weight that was proportional to its precision.RESULTS:Nineteen studies consisting of 13 independent cohorts met the inclusion criteria.The studiesincluded 995 577 participants and 5620 incident cases of digestive cancer with an average follow-up of 11.1 years.A significant inverse association was observed between energy intake and the incidence of digestive cancers.The RR of digestive cancers for the highest compared to the lowest caloric intake category was 0.90(95% CI 0.81-0.98,P < 0.05).The RR for an increment of 239 kcal/d energy intake was 0.97(95% CI 0.95-0.99,P < 0.05) in the fixed model.In subgroup analyses,we noted that energy intake was associated with a reduced risk of colorectal cancer(RR 0.90,95% CI 0.81-0.99,P < 0.05) and an increased risk of gastric cancer(RR 1.19,95% CI 1.08-1.31,P < 0.01).There appeared to be no association with esophageal(RR 0.96,95% CI 0.86-1.07,P > 0.05) or pancreatic(RR 0.79,95% CI 0.49-1.09,P > 0.05) cancer.Associations were also similar in studies from North America and Europe.The RR was 1.02(95% CI 0.79-1.25,P > 0.05) when considering the six studies conducted in North America and 0.87(95% CI 0.77-0.98,P < 0.05) for the five studies from Europe.CONCLUSION:Our findings suggest that high energy intake may reduce the total digestive cancer incidence and has a preventive effect on colorectal cancer.

Energy intake, oxidative stress and antioxidant in mice during lactation

Reproduction is the highest energy demand period for small mammals, during which both energy intake and expenditure are increased to cope with elevated energy requirements of offspring growth and somatic protection. Oxidative stress life history theory proposed that reactive oxygen species（ROS） were produced in direct proportion to metabolic rate, resulting in oxidative stress and damage to macromolecules. In the present study, several markers of oxidative stress and antioxidants activities were examined in brain, liver, kidneys, skeletal muscle and small intestine in non-lactating（Non-Lac） and lactating（Lac） KM mice. Uncoupling protein（ucps） gene expression was examined in brain, liver and muscle. During peak lactation, gross energy intake was 254% higher in Lac mice than in Non-Lac mice. Levels of H2O2 of Lac mice were 17.7% higher in brain（P〈0.05）, but 21.1%（P〈0.01） and 14.5%（P〈0.05） lower in liver and small intestine than that of Non-Lac mice. Malonadialdehyde（MDA） levels of Lac mice were significantly higher in brain, but lower in liver, kidneys, muscle and small intestine than that of Non-Lac mice. Activity of glutathione peroxidase（GSH-PX） was significantly decreased in brain and liver in the Lac group compared with that in the Non-Lac group. Total antioxidant capacity（TAOC） activity of Lac mice was significantly higher in muscle, but lower in kidneys than Non-Lac mice. Ucp4 and ucp5 gene expression of brain was 394% and 577% higher in Lac mice than in Non-Lac mice. These findings suggest that KM mice show tissuedependent changes in both oxidative stress and antioxidants. Activities of antioxidants may be regulated physiologically in response to the elevated ROS production in several tissues during peak lactation. Regulations of brain ucp4 and ucp5 gene expression may be involved in the prevention of oxidative damage to the tissue.

Influence of Familiarity on Energy Intake and Plasma Gut Hormone Concentration in Lean and Overweight Young Male Students

Objective This study is to examine the influence of familiarity on energy intake, eating behavior, and concentration of the plasma gut hormones in lean and overweight young male subjects. Methods Twenty-eight lean and twenty-eight overweight participants were recruited. Their food consumption was documented and analyzed when they had a test meal while they were paired with friends or strangers at the same weight stature. Their eating behavior was recorded with cameras hidden in the carton, and postprandial plasma gut hormone concentration were measured. Results Compared with overweight strangers（OS）, overweight friends（OF） had increased food consumption, prolonged and decreased number of chews per 10 g food. Compared with OS, postprandial plasma concentration of cholecystokinin-8 was significantly lower in OF group at 30, 60, and 90 min, whereas the concentration of glucagon-like peptide 1 was significantly lower at 60 and 90 min. Plasma ghrelin concentration was significantly higher in the OF group than that in the OS group at 90 and 120 min. No significant differences in gut hormone concentration were observed between lean strangers（LS） and lean friends（LF） groups at all time points. Conclusion Familiarity plays an important role in increasing energy intake and in changing of postprandial gut hormone concentration in overweight individuals.

Effect of Energy Intake during Dry Period on Production Performance of Postparturient Cows

healthy periparturient cows were randomly allocated into three groups and fed 100% energy diet (NRC standard diets), 120% energy diet and 80% energy diet, respectively, beginning at 28 days prior to anticipated parturition. After parturition, all the cows were provided with the lactation ration ad libitum until the day 56 postpartum. The objectives of the study were to investigate the effect of energy intake during the dry period on the production performance in the postpartum cows. The results indicated that the cows fed with high energy diet during the dry period had a lower dry material intake (DMI) and reduced milk production and a significant body weight (BW) loss compared with the cows fed with 80% energy diet and 100% energy diet. The results suggested that energy intake during the dry period was an important factor that influences and regulates DMI, milk production and energy equilibration of postparturient cows.

The Ability of Nile Tilapia to Regulate Protein and Energy Intake Evaluated by Carbon Relative Enrichment （δ^13C）

The aim of this study was to assess the ability of Nile tilapia to balance its own diet, when two ingredient mixes were offered, using carbon stable isotopes. In order to accomplish that, 225 Nile tilapia juveniles （average initial weight 5.0 g ± 0.5 g） were distributed in five tanks, each containing a group of 45 fish. One group of fish were fed exclusively with a high protein mix （HPM; δ^13C = -22.62‰）, the second one fed only with a low protein mix （LPM; δ^13C = -14.34‰）. The other groups had free access to both mixes （free choice system）. The fish from all tanks were fed four times a day. Muscle, liver and blood samples were collected at each five days （from 2 fish/tank/collection） for 86 days, except for the fish fed with LPM （fed for a 120 days period）. The samples were analyzed in a mass spectrometer and proportions of the mixes consumed were estimated through its carbon isotope enrichment （δ^13C）. Energy intake slightly decreased after the 50th day and protein consumption increased after the same period. However, consumption did not present a clear pattern in relation to the individual weight, i.e., protein consumption patterns are mainly related to the age of the individuals and it is not clear if it is also correlated to their weight. Additionally, this technique allowed the observation of differences regarding consumption among the individuals from the experimental group.

Effects of short photoperiod on energy intake,thermogenesis,and reproduction in desert hamsters(Phodopus roborovskii)

Desert hamsters(Phodopus roborovskii)are the least known species in the genus Phodopus with respect to ecology and physiology,and deserve scientific attention,particularly because of their small body size.Here,the responses of energy metabolism and reproductive function to short photoperiods in desert hamsters were investigated.Male and female desert hamsters were acclimated to either long day(LD)(L:D 16:8 h)or short day(SD)photoperiods(L:D 8:16 h)for three months,and then the females were transferred back to an LD photoperiod for a further five months,while at the end of the SD acclimation the males were killed and measurements were taken for serum leptin as well as molecular markers for thermogenesis.We found that like the other two species from the genus Phodopus,the desert hamsters under SD decreased body mass,increased adaptive thermogenesis as indicated by elevated mitochondrial protein content and uncoupling protein-1 content in brown adipose tissue,and suppressed reproduction compared to those under LD.However,different from the other two species,desert hamsters did not show any differences in energy intake or serum leptin concentration between LD and SD.These data suggest that different species from the same genus respond in different ways to the environmental signals,and the desert adapted species are not as sensitive to change in photoperiod as the other two species.

The use of animal sensor data for predicting sheep metabolisable energy intake using machine learning

The use of sensors for monitoring livestock has opened up new possibilities for the management of livestock in extensive grazing systems.The work presented in this paper aimed to develop a model for predicting the metabolisable energy intake(MEI)of sheep by using temperature,pitch angle,roll angle,distance,speed,and grazing time data obtained directly from wearable sensors on the sheep.A Deep Belief Network(DBN)algorithm was used to predict MEI,which to our knowledge,has not been attempted previously.The results demonstrated that the DBN method could predict the MEI for sheep using sensor data alone.The mean square error(MSE)values of 4.46 and 20.65 have been achieved using the DBN model for training and testing datasets,respectively.We also evaluated the influential sensor data variables,i.e.,distance and pitch angle,for predicting the MEI.Our study demonstrates that the application of machine learning techniques directly to on-animal sensor data presents a substantial opportunity to interpret biological interactions in grazing systems directly from sensor data.We expect that further development and refinement of this technology will catalyse a step-change in extensive livestock management,as wearable sensors become widely used by livestock producers.

Proteomic Analysis of the Small Intestine Reveals Adaptive Strategies for Energy Restriction of Phrynocephalus vlangalii at High Altitude

The environmental characteristics of hypothermia and hypoxia exert great selective pressure on the energy metabolism of high-altitude animals,especially the ectotherms.Current research on energy-limited adaptation of high-altitude ectotherms has focused on energy expenditures.However,the mechanisms of increasing energy intake in high-altitude ectotherms have been studied rarely.In order to investigate the adaptation mechanism of the small intestine,the key part of energy acquisition for animals,to energy limitation at high altitude in ectotherms,the gut proteins of Phrynocephalus vlangalii from high-and low-altitude populations were compared using label free proteomics.GO enrichment and KEGG pathway analysis showed that proteins associated with energy intake,such as those involved in oxidation-reduction processes,glutathione metabolism,oxidoreductase activity,cofactor binding,catalytic activity and metabolic pathways,were significantly up-regulated in high-altitude populations;while proteins associated with energy expenditure,such as immune responses and processes,membrane attack complexes,natural killer pathway and other immune-related processes,were significantly down-regulated in expression.

Using Sensewear armband and diet journal to promote adolescents' energy balance knowledge and motivation

Purpose： Educating adolescents about energy balance （EB） is essential for effective weight control. This study utilized the Sensewear （SWA） armband and a diet journal to promote adolescents＇ EB knowledge and motivation. Methods： Ninety sixth graders were randomly assigned into the experimental group （n = 46） who utilized SWA and diet journal for 7 consecutive days or the control group （n = 44） who did not. Both groups were pre- and post-measured on EB knowledge, situational interest, and weight. The experimental group was tracked on motivation effort, energy expenditure （EE）, and energy intake （EI）. Results： EB knowledge significantly increased and situational interest remained stable （except for total interest and enjoyment） over time, but these changes did not favor the experimental group. Situational interest and motivation effort were correlated with EE, EI, and/or EB. Conclusion： Tracking EB using the SWA and diet journal is motivating but has limited efficacy in promoting adolescents＇ EB knowledge. Using these two tools as educational technology in conjunction with a focused, systematic, and educational approach has the potential to leverage adolescents＇ EB knowledge, motivation, as well as behaviors for living an energy-balanced lifestyle.

Recovery of Hunger Sensations Associated with Low Preprandial Blood Glucose: An Easy Exit from Diabetes?

Background: Obesity, diabetes, asthma, autism, birth defects, dyslexia, attention deficit-hyperactivity disorder and schizophrenia have increased in children in the last half century. These increases may depend on the widespread, well known error in energy balance: the unremitting addition of fat at any will (decision) to eat. In most (60%) but not all people, the decision arises as conditioned before energy exhaustion of the energy available from previous meals. After meal suspension for few hours (up to 48 hours), healthy subjects identified the arousal of sensations of hunger that we named Initial Hunger (IH). After this identification, subjects distinguished IH from conditioned sensations before subsequent meals by mental comparison of the current arousal with the remembered IH. BG decreased to 76.6 ± 3.7 mg/dL and hunger sensations (Initial hunger, IH) arose spontaneously and corresponded to the complete exhaustion of the previous meals. Objective: Not Insulin Dependent (NID) diabetic people differ from fattening people in this: after meal suspension, they do not develop any hunger sensation nor the associated low blood glucose (BG). Methods: Meal suspension lets IH arise and after no arousal, reduction of energy intake. The two subjects consumed meals that provided at least 20 grams of animal protein and up to one kg of not-starchy vegetable (NSV) for 6 to 12 months. At reappearance of IH, we implemented an Initial Hunger Meal Pattern (IHMP). Results: We tried to implement IHMP training in two obese (BMI of 39 and 33) adults out of two consecutive recruitments of subjects who showed high fasting BG. We found an absence of BG decline to 76.6 ± 3.7 mg/dL and an absence of any hunger sensation after eating suspension. Both subjects lost 13% - 20% of their body weight and recovered 76.6 ± 3.7 mg/dL of BG and hunger sensations, i.e., went off diabetes. IHMP maintained the decreased body weight in the subsequent months. Conclusion: Diabetes develops for inveterate conditioned intake (when previous energy intake has not been fully exhausted before meals), excessive fattening (with presumed excessive post-absorption emission of fatty acids from fatty tissues), permanent loss of BG decline to 76.6 ± 3.7 mg/dL and permanent loss of physiological signals of hunger. A healthy, non-diabetic life may be recovered by painless loss of weight up to 20%. The body weight remained stable by implementing IHMP at reappearance of hunger sensations. This costs accurate energy intake planning instead of hunger endurance.