Effect of fat type and lysophosphatidylcholine addition to broiler diets on performance,apparent digestibility of fatty acids,and apparent metabolizable energy content

A completely randomized design study with a 3 × 2 factorial arrangement was conducted to evaluate the effects of three different fat sources (soybean oil, tallow, and poultry fat) with or without emulsifier supplementation on performance, coefficient of total tract apparent digestibility (CTTAD) of fatty acids, and apparent metabolizable energy (AME) content in broiler chickens. Two hundred and fifty-two one-day-old male Arbor Acres broiler chickens were randomly divided into 6 different treatments: (T1) basal diet containing soybean oil without lysophosphatidylcholine (LPC) supplementation, (T2) basal diet containing soybean oil with LPC supplementation, (T3) basal diet containing tallow without LPC supplementation, (T4) basal diet containing tallow with LPC supplementation, (T5) basal diet containing poultry fat without LPC supplementation, and (T6) basal diet containing poultry fat with LPC supplementation. Body weight gains from broiler chicks fed diets containing tallow were lower (P<0.05) than the body weight gains from chicks that were fed diets containing soybean oil or poultry fat in both the starter and grower periods. Birds fed diets containing tallow had the highest FCR (P<0.05), followed by the birds that were fed diets containing poultry fat, and soybean oil. The CTTAD of C16:0, C18:2, and C18:3n3 was greater (P<0.05) for broilers fed diets containing soybean oil than for those fed diets containing tallow or poultry fat in the starter period. The addition of LPC increased (P<0.05) body weight gain of broiler chickens in the starter period and the AME of the diets in the grower period, and tended to reduce FCR (P=0.072) in the starter period. LPC supplementation increased (P<0.05) the CTTAD of C16:0, C18:1n7 and C18:1n9 in the starter period, and of C18:2, and C18:3n3 in the grower period (P<0.05). There were no significant interactions between fat sources and the addition of LPC. These data indicated that LPC supplementation can improve body weight gain of broiler chickens in the starter period. This effect may be associated with an increase of CTTAD of FA due to LPC activity.     

Effects of dietary carbohydrates and temperatures on slow growing juvenile eels Anguilla anguilla

Synopsis The influence of the level of carbohydrate in a purified diet on the growth of slow-growing Anguilla anguilla maintained at different temperatures was examined. The average weight increase of eels maintained at temperatures of 25° or 27° C and fed a diet containing 20% or 30% glucose, was significantly higher than the mean weight increase of eels maintained at the same temperature but fed a diet containing soluble corn starch, at the same percentages. There was no significant difference in the mean weight of slow growing eels fed 10%, 20% and 30% soluble corn starch or 10% glucose. There was no significant difference in protein content (wet weight) among the experimental groups. However, elvers that were fed a high percentage of carbohydrates (glucose or starch) and maintained at 27° C had a higher percentage of lipids in body weight compared with the other experimental groups.     

Effects of chlordecone and malnutrition on immune response in rats

Effect of Chlordecone (Cd) and malnutrition on total body and spleen weights, and plaque forming cells (PFC) were studied. Rats were fed on normal, calcium (CaD), protein (PD) or Ca+P-deficient diets containing 0, 10 or 100 ppm of Cd for 2 or 4 weeks. High (95−100%) mortality was observed in malnourished rats treated with 100 ppm of Cd for 4 weeks. A slight decrease in body weight and an increase in spleen weight was observed in normal but not malnourished rats treated with 10 ppm of Cd for 4 weeks. PFC were significantly increased in both malnourished and Cd-treated rats. Similar increase in PFC was observed in rats fed on CaD but not PD diet containing 10 or 100 ppm of Cd. Whereas, rats fed on Ca+P-D diet containing 100 ppm of Cd exhibited a significant decrease in PFC.     

The control of lipogenesis by dietary linoleic acid and its influence on the deposition of fat.

The replacement of dietary starch by sucrose results in an increase in hepatic lipogenesis in the rat. When corn oil (4% by weight or 9% of the energy content of the diet) was included with the sucrose (20% by weight, 20% of the energy content) the lipogenic effect of the sucrose was completely suppressed. In contrast, when beef tallow replaced the corn oil, the induced activity caused by the sucrose was reduced by only approximately 20%. No significant differences were observed between males and females. These diets containing sucrose supplemented with either 4% (w/w) corn oil or 4% (w/w) beef tallow, were then used to ascertain whether or not the effects on hepatic lipogenesis were reflected in changes in the amount of fat deposited during growth from 4--24 weeks of age. It was shown that the percentage body fat was only statistically different (P less than 0.05) when animals fed sucrose-supplemented diets were compared with animals fed diets supplemented with sucrose and beef tallow. However, there were no significant differences in total carcass weight of these rats. The results are discussed in terms of the relative contribution of liver and adipose tissue to total lipogenesis and the factors which control the lipogenic activity in the two tissues.     

Body Fat Accumulation in Zebrafish Is Induced by a Diet Rich in Fat and Reduced by Supplementation with Green Tea Extract

Fat-rich diets not only induce obesity in humans but also make animals obese. Therefore, animals that accumulate body fat in response to a high-fat diet (especially rodents) are commonly used in obesity research. The effect of dietary fat on body fat accumulation is not fully understood in zebrafish, an excellent model of vertebrate lipid metabolism. Here, we explored the effects of dietary fat and green tea extract, which has anti-obesity properties, on body fat accumulation in zebrafish. Adult zebrafish were allocated to four diet groups and over 6 weeks were fed a high-fat diet containing basal diet plus two types of fat or a low-fat diet containing basal diet plus carbohydrate or protein. Another group of adult zebrafish was fed a high-fat diet with or without 5% green tea extract supplementation. Zebrafish fed the high-fat diets had nearly twice the body fat (visceral, subcutaneous, and total fat) volume and body fat volume ratio (body fat volume/body weight) of those fed low-fat diets. There were no differences in body fat accumulation between the two high-fat groups, nor were there any differences between the two low-fat groups. Adding green tea extract to the high-fat diet significantly suppressed body weight, body fat volume, and body fat volume ratio compared with the same diet lacking green tea extract. 3-Hydroxyacyl-coenzyme A dehydrogenase and citrate synthase activity in the liver and skeletal muscle were significantly higher in fish fed the diet supplemented with green tea extract than in those fed the unsupplemented diet. Our results suggest that a diet rich in fat, instead of protein or carbohydrate, induced body fat accumulation in zebrafish with mechanisms that might be similar to those in mammals. Consequently, zebrafish might serve as a good animal model for research into obesity induced by high-fat diets.     

Effects of dietary fish oil on thyroid hormone signaling in the liver

n?3 polyunsaturated fatty acids (PUFAs) present in fish oil (FO) potently decrease serum lipids, which is also an effect of thyroid hormones. Both PUFAs and thyroid hormones affect hepatic lipid metabolism, and here we hypothesized that a long-term diet rich in n?3 PUFAs would enhance thyroid hormone action in the liver. Female rats received isocaloric and normolipid diets containing either soybean oil (SO) or FO during lactation. Male offspring received the same diet as their dams since weaning until sacrifice when they were 11 weeks old. FO group, as compared to SO group, exhibited lower body weight since 5 weeks of age until sacrifice, with no alterations in food ingestion, lower retroperitoneal white fat mass and elevated inguinal fat mass relative to body weight, with unchanged water and lipid but reduced protein percentage in their carcasses. FO diet resulted in lower serum triglycerides and cholesterol. Serum total triiodothyronine, total thyroxine and thyrotropin were similar between groups. However, liver thyroid hormone receptor (TR) β1 protein expression was higher in the FO group and correlated negatively with serum lipids. Liver 5′-deiodinase activity, which converts thyroxine into triiodothyronine, was similar between groups. However, the activity of hepatic mitochondrial glycerophosphate dehydrogenase, the enzyme involved in thermogenesis and a well-characterized target stimulated by T3 via TRβ1, was higher in the FO group, suggesting enhancement of thyroid hormone action. These findings suggest that the increase in thyroid hormone signaling pathways in the liver may be one of the mechanisms by which n?3 PUFAs exert part of their effects on lipid metabolism.     

Influence of steam pelleting on the feeding value of Tower and Candle rapeseed products for broiler chickens

Male broiler chickens were offered diets containing up to 30% Tower rapeseed meal, with these diets being prepared in mash or steam pelleted (crumble) form. In 4 experiments, birds receiving a maize and soya bean meal control diet showed a significant improvement in weight gain when crumbles, rather than mash diets, were used. With isocaloric, isonitrogenous diets containing rapeseed meal, no such improvement in growth rate was observed. Steam pelleting exerted no consistent effect on feed conversion. There was no significant difference in the growth rate of birds receiving mash diets irrespective of composition, while for crumbled diets, birds consuming the maize and soya bean control diet were heavier than comparable rapeseed-fed birds, with this difference being significant in 2 experiments. By adding fat, necessary to maintain rapeseed diets isocaloric, after the pelleting process, it was shown that fat per se was not responsible for failure to elicit a growth response with pelleted rapeseed meal diets. The response to pelleting was similar with diets prepared in an experimental pelleting machine at the university or by a commercial feed mill. Reduction in amino acid availability, in particular of arginine, is tentatively discussed in relation to the non-improved growth rate observed with pelleted diets containing rapeseed meal. Improvement in growth rate with pelleted vs. mash diets containing whole, raw rapeseeds is interpreted as a response to the heat treatment involved with the pelleting process.     

Failure to induce weight gain with palatable diets in monkeys (Macaca mulatta)

Three diets popularly used to produce obesity in rodents were offered to male rhesus monkeys. A high fat diet (fat: 50% of calories) enhanced the daily caloric intake of the monkeys, but only slight and non-significant increases in body weight were observed over a period of six weeks. However, an increase in feeding efficiency was observed. Providing monkeys with an assorted, palatable supermarket diet failed to induce them to overeat. There were no changes in total caloric intake or in body weight. When the monkeys were supplemented with a bottle of 32% sucrose solution, in addition to a commercial monkey biscuit and tap water, a significant increase in caloric intake was observed, but no change in body weight occurred. Thus, palatable and calorically dense diets failed to induce sufficient increases in intake to produce change in body weight in non-human primates. Based on these results, only the high fat diet has greatest potential to produce obesity, and such obesity, if it occurs, will likely require long term experiments.     

Dietary <Emphasis Type="SmallCaps">l</Emphasis>-leucine and <Emphasis Type="SmallCaps">l</Emphasis>-alanine supplementation have similar acute effects in the prevention of high-fat diet-induced obesity

High-protein diets have been shown to alleviate detrimental effects of high-fat diets and this effect can be partially mimicked by dietary l-leucine supplementation. Here, we aimed to elucidate the early mechanisms and the specificity of leucine effects. We performed a 1-week trial with male C57BL/6 mice fed ad libitum with semisynthetic high-fat diets containing an adequate (10 % w/w, AP) or high (50 % w/w, HP) amount of whey protein, or supplemented with l-leucine corresponding to the leucine content within the HP diet (Leu) or supplemented with equimolar l-alanine (Ala). Food and water intake were monitored continuously using a computer-controlled monitor system and body composition changes were assessed using quantitative NMR. HP completely prevented the AP-induced accumulation of body fat. Leu and Ala resulted in a similar reduction of body fat accumulation which was intermediate between AP and HP. There were no significant effects on plasma glucose or insulin. Triacylglycerol content and gene expression of lipogenesis enzymes in liver as well as plasma cholesterol were reduced by HP compared to AP with Leu and Ala again showing intermediate effects. Body fat gain and liver triacylglycerols were strongly correlated with total energy intake. Water intake was rapidly increased by HP feeding and total water intake correlated strongly with total amino nitrogen intake. We concluded that the positive effects of high-protein diets on metabolic syndrome associated traits are acutely due to effects on satiety possibly linked to amino nitrogen intake and on the subsequent suppression of liver lipogenesis without evidence for a specific leucine effect.     

Growth increments and some flesh and gonad characteristics of juvenile coho salmon receiving diets supplemented with 17α-methyltestosterone

Juvenile coho salmon Oncorhynchus kisutch (Walbaum) received a diet of Oregon Moist Pellets supplemented with either 10, 1, 0.2 or 0 ppm of 17α-methyltestosterone for 72 weeks. The fish were held in fresh water during the first 57 weeks and in salt water during the remaining time of the study. At the end of the fresh water residency, the fish receiving 10 and 1 ppm of steroid showed a net increase in weight of 125 and 71 % respectively over the controls. Both test groups also gained in length, but the 10 ppm group gained proportionately less, which resulted in a thicker body. After transfer to salt water at the normal time of smolting, there was a decrease in the rate of growth in weight and length of the two groups receiving the high doses of steroid. The decrease was most noticeable in the 10 ppm group and a number of mortalities occurred in this group.
Testes of fish receiving 10 ppm of the steroid became hypertrophied and later degenerated with loss of spertnatogonia; the ovaries were not affected. 17α-methyltestosterone fed at 10 ppm for 49 weeks increased the lipid content of the flesh from 2.4 to 3.5 % and decreased the amount of flesh from 35.0 to 28.5 % of body weight. No change in the moisture content was found. External changes noted in the 10 ppm group included loss of silvering, deepening of the body, particularly in the region of the anal fin, and widening of the lower jaw.     

Oilcakes as protein sources in supplementary diets for the growth of Cirrhinus mrigala (Ham.) fingerlings: laboratory and field studies

Five isonitrogenous diets (1-5) with 40% protein using oilcakes as protein sources were formulated and fed to Cirrhinus mrigala fingerlings maintained both under laboratory and field conditions. Water soaking of oilcakes for 24 h before incorporation in the diets helped in the reduction of antinutrient factors (phytase and tannins). Live weight gain in fish fingerlings fed on a diet containing groundnut oilcake (GNOC) was significantly (P < 0.05) enhanced in comparison to the other dietary treatments when examined at the end of a feeding schedule. Laboratory studies have further revealed that APD, PER, GPR and GER values were significantly (P < 0.05) enhanced, while those of feed conversion ratio were significantly (P < 0.05) reduced in fish fed on diet 1 containing GNOC. An analysis of water samples collected at two hourly interval from the aquaria revealed low levels of total ammonia (N-NH4+) excretion and reactive phosphate (O-PO4) production in fish fed on diet 1. Proximate carcass composition also revealed high accumulation of protein, fat, energy and phosphorus in fingerlings fed on a diet containing GNOC. Even in field studies a significant (P < 0.05) increase in mean fish weight gain and specific growth rate (SGR% d(-1)) was observed in fingerlings fed on diet 1, followed by canola (2), sunflower (3), mustard oilcake (4) and sesame (5). Water and sediment quality characteristics also correlated well with fish growth.     

Changes in body composition and efficiency of food utilization for growth in young adult female rats before, during and after a period of food restriction.

Changes in body composition were studied in three groups of young adult female rats; the treatments were (1) ad libitum food intake to obtain normal growth, (2) restricted food intake to cause body weight loss, and (3) restricted followed by ad libitum food intake to obtain recovery of lost body weight. In each of the three groups of rats the percentage body water was linearly and negatively correlated with the percentage body fat, the weight of body water was linearly and positively correlated with the weight of body protein, and the ratio of the weight of body protein to water was relatively constant at 1:3.20 +/- 0.02 (mean +/- standard error). The percentage body water in the fat-free body was linearly and negatively correlated with fat-free body weight during normal growth between 109 and 334 g body weight but positively correlated during body weight loss and recovery. During recovery of body weight rats laid down more fat and less protein than during normal growth through the same body weight range and the percentage of digestible energy retained as body tissue was increased.     

Comparison of high-protein diets and leucine supplementation in the prevention of metabolic syndrome and related disorders in mice

High-protein diets have been shown to promote weight loss, to improve glucose homeostasis and to increase energy expenditure and fat oxidation. We aimed to study whether leucine supplementation is able to mimic the alleviating effects of high-protein diets on metabolic syndrome parameters in mice fed high-fat diet.Male C57BL/6 mice were fed for 20 weeks with semisynthetic high-fat diets (20% w/w of fat) containing either an adequate (10% protein, AP) or high (50% protein, HP) amount of whey protein, or an AP diet supplemented with l-leucine corresponding to the leucine content of the HP diet (6% leucine, AP+L). Body weight and composition, energy expenditure, glucose tolerance, hepatic triacylglycerols (TG), plasma parameters as well as expression levels of mRNA and proteins in different tissues were measured. HP feeding resulted in decreased body weight, body fat and hepatic TG accumulation, as well as increased insulin sensitivity compared to AP. This was linked to an increased total and resting energy expenditure (REE), decreased feed energy efficiency, increased skeletal muscle (SM) protein synthesis, reduced hepatic lipogenesis and increased white fat lipolysis. Leucine supplementation had effects that were intermediate between HP and AP with regard to body composition, liver TG content, insulin sensitivity, REE and feed energy efficiency, and similar effects as HP on SM protein synthesis. However, neither HP nor AP+L showed an activation of the mammalian target of rapamycin pathway in SM. Leucine supplementation had no effect on liver lipogenesis and white fat lipolysis compared to AP. It is concluded that the essential amino acid leucine is able to mimic part but not all beneficial metabolic effects of HP diets.     

Multi-Functional Roles of Chitosan as a Potential Protective Agent against Obesity

Chitosan, a natural polysaccharide comprising copolymers of glucosamine and N-acetylglucosamine, has been shown to have anti-obesity properties. Two experiments (Exp. 1 and Exp. 2) were performed to determine the role of chitosan on dietary intake, body weight gain, and fat deposition in a pig model, as well as identifying potential mechanisms underlying the anti-obesity effect of chitosan. In Exp. 1, the nutrient digestibility experiment, 16 pigs (n = 4/treatment) were randomly allocated to one of four dietary treatments as follows: 1) basal diet; 2) basal diet plus 300 ppm chitosan; 3) basal diet plus 600 ppm chitosan; 4) basal diet plus 1200 ppm chitosan. The main observation was that crude fat digestibility was lower in the 1200 ppm chitosan group when compared with the control group (P<0.05). In Exp. 2, a total of 80 pigs (n = 20/treatment) were offered identical dietary treatments to that offered to animals in Exp. 1. Blood samples were collected on day 0, day 35 and at the end of the experiment (day 57). Animals offered diets containing 1200 ppm chitosan had a lower daily dietary intake (P<0.001) and body weight gain (P<0.001) from day 35 to 57 when compared with all the other treatment groups. Animals offered diets containing 1200 ppm chitosan had a significantly lower final body weight (P<0.01) when compared with all the other treatment groups. The decreased dietary intake observed in the 1200 ppm chitosan group was associated with increased serum leptin concentrations (P<0.001) and a decrease in serum C-reactive protein (CRP) concentrations (P<0.05). In conclusion, the results of this study highlight novel endocrine mechanisms involving the modulation of serum leptin and CRP concentrations by which chitosan exhibits anti-obesity properties in vivo.     

Combined effects of dietary protein type and fat level on the body fat-reducing activity of conjugated linoleic acid (CLA) in rats

The interaction of dietary protein type and fat level on the body fat-reducing activity of conjugated linoleic acid (CLA) was studied in male rats fed diets containing casein (CAS) or soy protein (SOY) as a protein source with low fat (LF, 6.0% soybean oil) or high fat (HF, 13.0% soybean oil) combinations for 4 weeks. CLA was added at the 1.0% level to all diets. The weight of perirenal adipose tissue tended to be lower in the SOY groups than in the corresponding CAS groups, and the difference between the LF diets was significant. The weight of epididymal adipose tissue showed a similar but insignificant trend. The weight of brown adipose tissue was heaviest on the SOY-HF diet and lowest on two CAS diets, the SOY-LF diet being intermediate. The concentration of serum leptin was lowest on the SOY-LF diet and was significantly lower than that of the corresponding CAS group, but this difference disappeared when the dietary fat level increased. The serum cholesterol-lowering activity of SOY in relation to CAS was reproduced even when CLA was given. Thus the body fat-reducing activity of CLA was most marked when rats were fed the SOY-LF diet. Although the CAS-HF diet increased body fat deposition, the magnitude of the reduction by lowering dietary fat level was more marked than in the case of SOY. These results indicate a complicated interaction of dietary manipulations with the body fat-reducing effect of CLA, but the combination of CLA with the SOY-LF diet appears to be an appropriate approach.     

Combined Effects of Dietary Protein Type and Fat Level on the Body Fat-Reducing Activity of Conjugated Linoleic Acid (CLA) in Rats

The interaction of dietary protein type and fat level on the body fat-reducing activity of conjugated linoleic acid (CLA) was studied in male rats fed diets containing casein (CAS) or soy protein (SOY) as a protein source with low fat (LF, 6.0% soybean oil) or high fat (HF, 13.0% soybean oil) combinations for 4 weeks. CLA was added at the 1.0% level to all diets. The weight of perirenal adipose tissue tended to be lower in the SOY groups than in the corresponding CAS groups, and the difference between the LF diets was significant. The weight of epididymal adipose tissue showed a similar but insignificant trend. The weight of brown adipose tissue was heaviest on the SOY-HF diet and lowest on two CAS diets, the SOY-LF diet being intermediate. The concentration of serum leptin was lowest on the SOY-LF diet and was significantly lower than that of the corresponding CAS group, but this difference disappeared when the dietary fat level increased. The serum cholesterol-lowering activity of SOY in relation to CAS was reproduced even when CLA was given. Thus the body fat-reducing activity of CLA was most marked when rats were fed the SOY-LF diet. Although the CAS-HF diet increased body fat deposition, the magnitude of the reduction by lowering dietary fat level was more marked than in the case of SOY. These results indicate a complicated interaction of dietary manipulations with the body fat-reducing effect of CLA, but the combination of CLA with the SOY-LF diet appears to be an appropriate approach.     

Effect of soy and milk whey protein isolates and their hydrolysates on weight reduction in genetically obese mice

The effect on genetically obese mice of a milk whey protein isolate (WPI) and soy protein isolate (SPI) and their hydrolysates (WPI-H, SPI-H) on the rate of body fat disappearance was investigated. Male yellow KK mice were made obese by feeding with a high-fat diet containing 30% fat from 6 to 10 weeks of age. They were then fed with an energy-restricted low fat (5.0%) and high protein (35% WPI, WPI-H, SPI or SPI-H) diet for 2 weeks at the 60% level of energy intake by mice on laboratory feed. During the weight reduction period, the body weight of the WPI, WPI-H, SPI and SPI-H groups changed by -9.1, -9.1, -10.0 and -11.1 g/14 days, respectively, the reduction being significantly lower in the SPI-H group than in the WPI and WPI-H groups. The plasma total cholesterol level was significantly lower with the SPI diet, and the plasma glucose level was lower with the SPI and SPI-H diets than with the WPI and WPI-H diets. Although the body protein content was comparable in all the groups, the body fat content was significantly lower with the SPI diet than with the WPI diet, and was also significantly lower with the SPI-H diet than with the WPI and WPI-H diets. The weight of the perirenal fat pads was significantly lower with the SPI-H diet than with the WPI and WPI-H diets. These results indicate that SPI and SPI-H are suitable protein sources in an energy-restricted diet for treating obesity.     

Effect of Soy and Milk Whey Protein Isolates and Their Hydrolysates on Weight Reduction in Genetically Obese Mice

The effect on genetically obese mice of a milk whey protein isolate (WPI) and soy protein isolate (SPI) and their hydrolysates (WPI-H, SPI-H) on the rate of body fat disappearance was investigated. Male yellow KK mice were made obese by feeding with a high-fat diet containing 30% fat from 6 to 10 weeks of age. They were then fed with an energy-restricted low fat (5.0%) and high protein (35% WPI, WPI-H, SPI or SPI-H) diet for 2 weeks at the 60% level of energy intake by mice on laboratory feed. During the weight reduction period, the body weight of the WPI, WPI-H, SPI and SPI-H groups changed by -9.1, -9.1, -10.0 and -11.1 g/14 days, respectively, the reduction being significantly lower in the SPI-H group than in the WPI and WPI-H groups. The plasma total cholesterol level was significantly lower with the SPI diet, and the plasma glucose level was lower with the SPI and SPI-H diets than with the WPI and WPI-H diets. Although the body protein content was comparable in all the groups, the body fat content was significantly lower with the SPI diet than with the WPI diet, and was also significantly lower with the SPI-H diet than with the WPI and WPI-H diets. The weight of the perirenal fat pads was significantly lower with the SPI-H diet than with the WPI and WPI-H diets. These results indicate that SPI and SPI-H are suitable protein sources in an energy-restricted diet for treating obesity.     

DO‐SRS imaging of diet regulated metabolic activities in Drosophila during aging processes

Lipid metabolism plays crucial roles during aging processes, but how it is regulated by diets and how it interplays with aging still remain unclear. We proposed a new optical imaging platform by integrating heavy water (D₂O) probing with stimulated Raman scattering (DO‐SRS) microscopy, for the first time, to directly visualize and quantify lipid metabolism regulated by different diets and insulin signaling pathway in Drosophila fat body during aging. We found that calorie restriction, low protein diet, and (moderately) high protein and high sucrose diets enhanced lipid turnover in flies at all ages, while (moderately) high fructose and glucose diets only promoted lipid turnover in aged flies. The measured lipid turnover enhancements under diverse diets were due to different mechanisms. High protein diet shortened the lifespan while all other diets extended the lifespan. Downregulating the insulin signaling pathway enhanced lipid turnover, which is likely related to lifespan increase, while upregulating insulin signaling pathway decreased lipid turnover that would shorten the lifespan. Our study offers the first approach to directly visualize spatiotemporal alterations of lipid turnover in aging Drosophila in situ, for a better understanding of the interconnections between lipid metabolism, diets, and aging.     

Energieumsatz wachsender Broilerküken bei Gruppenhaltung in Abhängigkeit von der Umgebungstemperatur

Feeding 2‐weeks old broiler chicks on gibberellic acid (GA₃)‐containing diets (0, 1, 5, 25 and 125 ppm) for 3‐weeks led, generally, to nonsignificant increase of body weight, decreased feed consumption and better feed conversion (on 25–125 ppm). Yet, the percentages of the carcass and the other organs (liver, gizzard, heart) and glands (adrenal, thyroid and pituitary) weights were lower comparing with the control (0 level). Blood protein and magnesium concentrations raised significantly. Blood glucose increased but not significantly. There was remarkable decrease (P≤.01) in transaminases activity. The muscular protein decreased, whereas the fat percentage significantly increased. The bone reflected lower density and mineral (calcium, magnesium and phosphorus) contents. GA₃ led to numerous histological lesions in different organs. Two‐weeks withdrawal period did not ameliorate the negative effects of GA₃‐inclusion whether on the dressing percentages, blood picture, or on the muscles and bone constituents.