Food Utilization Rate Research Articles

Gut fungi of black-necked cranes (Grus nigricollis) respond to dietary changes during wintering

BackgroundMigratory birds exhibit heterogeneity in foraging strategies during wintering to cope with environmental and migratory pressures, and gut bacteria respond to changes in host diet. However, less is known about the dynamics of diet and gut fungi during the wintering period in black-necked cranes (Grus nigricollis).ResultsIn this work, we performed amplicon sequencing of the trnL-P6 loop and ITS1 regions to characterize the dietary composition and gut fungal composition of black-necked cranes during wintering. Results indicated that during the wintering period, the plant-based diet of black-necked cranes mainly consisted of families Poaceae, Solanaceae, and Polygonaceae. Among them, the abundance of Solanaceae, Polygonaceae, Fabaceae, and Caryophyllaceae was significantly higher in the late wintering period, which also led to a more even consumption of various food types by black-necked cranes during this period. The diversity of gut fungal communities and the abundance of core fungi were more conserved during the wintering period, primarily dominated by Ascomycota and Basidiomycota. LEfSe analysis (P < 0.05, LDA > 2) found that Pyxidiophora, Pseudopeziza, Sporormiella, Geotrichum, and Papiliotrema were significantly enriched in early winter, Ramularia and Dendryphion were significantly enriched in mid-winter, Barnettozyma was significantly abundant in late winter, and Pleuroascus was significantly abundant in late winter. Finally, mantel test revealed a significant correlation between winter diet and gut fungal.ConclusionsThis study revealed the dynamic changes in the food composition and gut fungal community of black-necked cranes during wintering in Dashanbao. In the late wintering period, their response to environmental and migratory pressures was to broaden their diet, increase the intake of non-preferred foods, and promote a more balanced consumption ratio of various foods. Balanced food composition played an important role in stabilizing the structure of the gut fungal community. While gut fungal effectively enhanced the host’s food utilization rate, they may also faced potential risks of introducing pathogenic fungi. Additionally, we recongnized the limitations of fecal testing in studying the composition of animal gut fungal, as it cannot effectively distinguished between fungal taxa from food or soil inadvertently ingested and intestines. Future research on functions such as cultivation and metagenomics may further elucidate the role of fungi in the gut ecosystem.

Anti-Obesity Effect of Combining White Kidney Bean Extract, Propolis Ethanolic Extract and CrPi3 on Sprague-Dawley Rats Fed a High-Fat Diet.

Obesity has been associated with the occurrence and prevalence of various chronic metabolic diseases. The management of obesity has evolved to focus not only on reducing weight, but also on preventing obesity-related complications. Studies have shown that bioactive components in natural products like white kidney bean extract (WKBE), propolis ethanolic extract (PEE), and chromium picolinate (CrPi3) showed anti-obesity properties. However, no studies have examined the outcomes of combining any of these nutraceutical supplements. We compared the effects of HFD supplemented with WKBE, WKBE+PEE, or WKBE+PEE+CrPi3 against control and obese groups using Sprague-Dawley rats fed a 45% high-fat diet as an in vivo model. Nutritional parameters, biochemical parameters, and biomarkers of cardiovascular disease, liver function, kidney function, and gut health were among the comparable effects. Our findings showed that combining the three nutraceutical supplements had a synergetic effect on reducing weight gain, food utilization rate, abdominal fat, serum lipids, arterial and hepatic lipids, risk of cardiovascular disease, and blood glucose level, in addition to improving renal function and gut microbiota. We attributed these effects to the α-amylase inhibitor action of WKBE, flavonoids, and polyphenol content of PEE, which were potentiated with CrPi3 resulting in a further reduction or normalization of certain parameters.

Protein efficiency ratio of genetically modified pork powder with fat-1 gene

To evaluate the protein efficiency ratio(PER) of genetically modified pork powder with fat-1 gene(GM group), and thus evaluate whether the nutritional evaluation value of fat-1 gene pork powder has changed. Sixty weaned SD rats(60-80 g) were randomly divided into casein group, parental control group and GM group according to sex and weight, 20 rats in each group, half of each sex. The rats in the three groups were fed with corresponding formulated feed containing 10% protein for 28 days. The body weight and food intake of each group were recorded weekly. Blood was collected at the end of the experiment to determine hematology and blood biochemical indexes. The food utilization rate, organ/body weigh indexes, PER and corrected PER were calculated. The weight of rats in all groups increased steadily during the experimental period. Statistically significant differences were found in some hematology and blood biochemical indexes and organ/body weigh indexes. No biologically significant changes were found. The food utilization rate of GM group was higher than that of casein group(P&lt;0.05), which was equivalent to that in the parental control group. The PER of both genetically modified pork powder with fat-1 gene and parental white pork powder were higher than that of casein(P&lt;0.05). The PER of genetically modified pork powder with fat-1 gene was equal to that of its parental white pork powder.

Digestive Characteristics of Hyphantria cunea Larvae on Different Host Plants

Digestive physiology mediates the adaptation of phytophagous insects to host plants. In this study, the digestive characteristics of Hyphantria cunea larvae feeding preferences on different host plants were investigated. The results showed that the body weight, food utilization, and nutrient contents of H. cunea larvae feeding on the high-preference host plants were significantly higher than those feeding on the low-preference host plants. However, the activity of larval digestive enzymes in different host plants presented an opposite trend, as higher α-amylase or trypsin activity was observed in the group feeding on the low-preference host plants than that feeding on the high-preference host plants. Upon treatment of leaves with α-amylase and trypsin inhibitors, the body weight, food intake, food utilization rate, and food conversion rate of H. cunea larvae significantly decreased in all host plant groups. Furthermore, the H. cunea comprised highly adaptable compensatory mechanisms of digestion involving digestive enzymes and nutrient metabolism in response to digestive enzyme inhibitors. Taken together, digestive physiology mediates the adaptation of H. cunea to multiple host plants, and the compensatory effect of digestive physiology is an important counter-defense strategy implemented by H. cunea to resist plant defense factors, especially the insect digestive enzyme inhibitors.

Survival Rate and Food Utilization Rate of the Red Nila Fish (Oreochromis sp) Utilizing synthetic feed additives Seaweed (Gracilaria sp)

In the fish farming business, feed is the highest operational cost, which reaches more than 60% of the total production cost. Therefore, the fish feed can be processed independently to reduce production costs in aquaculture businesses. This study aimed to determine the survival rate and feed efficiency of red tilapia (Oreochromis sp) fed artificial feed with the addition of seaweed (Gracilaria sp). This research was carried out from June to September 2021 at the Integrated Laboratory of Khairun University. This study used four treatments, and each treatment was repeated three times. The treatment tried is A (Artificial feed with the addition of Gracilaria sp 10 gr); B (Artificial feed with the addition of Gracilaria sp 20 gr; C (Artificial feed with the addition of Gracilaria sp 30 gr); and D (Artificial feed without the addition of Gracilaria sp.). The research variables included calculating the survival rate (SR), Feed Conversion Ratio (FCR), and observing water quality during the study. The highest survival value was in treatment B at 97.78%, while the lowest was in treatment A at 73.33%. The highest feed conversion ratio was in treatment D, 1.97, followed by treatments A and B, 1.48, and the lowest in treatment C, 0.64. The results of water quality measurements during the study, namely DO, range from 6-6.8 in all treatments, pH ranged from 7-7.6, and temperature ranged from 28-290C. The best survival rate (SR) of red tilapia-fed artificial feed with the addition of Gracilaria sp seaweed was best in treatment B, 97.78%, and the best feed conversion ratio (FCR) was in treatment C, which was 0.64 g.

Subchronic Toxicity of GmDREB3 Gene Modified Wheat in the Third Generation Wistar Rats.

The aim of the current study was to evaluate the subchronic toxicity of GmDREB3 gene modified wheat in the third generation rats. SPF Wistar rats were fed with transgenic wheat diet (Gm), parental wheat diet (Jimai22) and AIN-93 rodent diet (Control), respectively, for two generations, to produce the third generation rats which were used for this study. The selected fresh weaned offspring rats (20/sex/group) were given the same diet as their parents for 13 weeks. No toxicity-related changes were observed in rats fed with Gm diet in the following respects: clinical signs, body weights, body weight gains, food consumption, food utilization rate, urinalysis, hematology, serum biochemistry and histopathology. The results from the present study demonstrated that 13 weeks consumption of Gm wheat did not cause any adverse effects in the third generation rats when compared with the corresponding Jimai22 wheat.

Subchronic Oral Toxicity Evaluation of Sodium Dehydroacetate: A 90-day Repeated Dose Study in Rats

ObjectiveThe present study was undertaken to evaluate the subchronic oral toxicity of sodium dehydroacetate (DHA-Na) and to determine the point of departure (POD), which is a critical factor in the establishment of an acceptable dietary intake. MethodsDHA-Na was administered once daily by gavage to Sprague-Dawley rats at dose levels of 0.0, 31.0, 62.0, and 124.0 mg/kg BW per day for 90 days, followed by a recovery period of 4 weeks in the control and 124.0 mg/kg BW per day groups. The outcome parameters were mortality, clinical observations, body weights, food consumption, hematology and clinical biochemistry, endocrine hormone levels, and ophthalmic, urinary, and histopathologic indicators. The benchmark dose (BMD) approach was applied to estimate the POD. ResultsSignificant decreases were found in the 62.0 and 124.0 mg/kg BW groups in terms of the body weight and food utilization rate, whereas a significant increase was found in the thyroid stimulating hormone levels of the 124.0 mg/kg BW group. Importantly, the 95% lower confidence limit on the BMD of 51.7 mg/kg BW was modeled for a reduction in body weight. ConclusionThe repeated-dose study indicated the slight systemic toxicity of DHA-Na at certain levels (62.0 and 124.0 mg/kg BW) after a 90-day oral exposure.

Evaluation of the prevention of fat accumulation efficacy of sweet potato fermented products in vivo

Over-nutrition rather than under-nutrition is an important public health challenge in some developed countries. However, the under-nutrition is a major problem according to the global perspective. Therefore, the research and development (R&amp;D) of agricultural functional materials or products for the prevention of fat accumulation is urgently needed. In this experiment, Sprague Dawley (SD) rats in the normal control group were fed with the normal composition for 8 weeks during the experiment. SD rats in the negative control group and three sweet potato fermented products (SPFP) groups were fed a high fat diet for 8 weeks during the experiment. According to the experimental design, three doses SPFP [250, 500, and 1,000 mg/kg body weight (BW)] will be administered after 4 weeks of feeding the high fat diet. During the experiment, BW of the SD rats was recorded every week and blood, liver, and body fat were collected for analysis of body fat rate, blood lipid content, blood glucose content, liver lipid content, and liver and renal functions. Based on the results, the consumption of SPFP does not affect liver and kidney functions, indicating that SPFP is a safe and edible agricultural material. BW change of the normal control group was significantly lower than that of the negative control group and three SPFP groups (p &lt; 0.05). In addition, there was no significant difference in the BW change rate among the groups eat the high fat feed (p &gt; 0.05), but the trend of BW change rate in the low and middle doses of SPFP groups was lower than that in the other high fat feed groups. The food utilization rate of the high fat diet group was significantly higher than that of the normal diet group (p &lt; 0.05). The body fat rate of the normal control group was significantly lower than that of the high fat feed groups (p &lt; 0.05). There was no significant difference between the high fat feed groups (p &gt; 0.05). However, the trend showed that the body fat rate of the low and middle doses of SPFP groups were lower than that of the negative control group and the high dose of SPFP group. In addition, the results of other measurement indicators such as blood lipid content, blood glucose content, and liver lipid content did not show any negative effects of SPFP. Based on the above results, although SPFP on the prevention of body fat accumulation was not significantly exhibited, however, the trend shows that the low and middle doses of SPFP can decrease body fat production. Taken these results together, SPFP may has the potential for the prevention of fat accumulation.

Biosafety evaluation of Li2Si2O5 whisker-reinforced glass-ceramics

Lithium disilicate (Li2Si2O5) glass-ceramic is a commonly used dental ceramic material. In this study, Li2Si2O5 whiskers were prepared by the hydrothermal method, mixed with Li2Si2O5 glass powders, and Li2Si2O5 whisker-reinforced glass-ceramics were prepared by reaction sintering. The biosafety of the new Li2Si2O5 glass-ceramics were evaluated by in vitro cytotoxicity, hemolysis, oral mucosal irritation, acute systemic toxicity, and subacute systemic toxicity (oral route) tests according to ISO 7405/ISO 10993 standards. The cytotoxicity test results showed that the cell growth of the experimental group was good, and the cell number and morphology were not significantly different from those of the blank group (P> 0.05). The toxicity grading for both experimental and blank control groups were 0. The hemolysis rate of the material was 1.25%, which indicated that it did not cause hemolytic reaction. The material was non-irritating to the oral mucosa. In acute systemic toxicity test, animals in the experimental group showed increased body weight, moved freely, with no signs of poisoning. The food utilization rate and relative growth rate (change of the weight) of rats in the subacute systemic toxicity test were not statistically different from those of the control group (P > 0.05). Preliminary evaluation of the biosafety of the Li2Si2O5 whisker-reinforced glass-ceramics showed that it met the existing regulatory standards, and further biosafety experiments can be conducted, following which the material may be expected to be applied in clinical practice.

Effects of dietary Lactobacillus acidophilus and tussah immunoreactive substances supplementation on physiological and immune characteristics of sea cucumber (Apostichopus japonicus)

To investigate the effects of Lactobacillus acidophilus and tussah immunoreactive substances (TIS) supplementation alone or together on the growth performance, digestive and immune-related enzyme activities, and intestinal microbiota of the sea cucumber Apostichopus japonicus, a feeding experiment was conducted. The supplementation of L. acidophilus and TIS together produced the maximum digestive and immune activities, while the minimum values occurred in the control group. No remarkable differences in enzyme activities were observed when supplemented individually. Dietary L. acidophilus and TIS in combination might be more capable of improving digestive capacity, food utilization rate, phosphatase-responsiveness and antioxidants. Furthermore, the supplementation of L. acidophilus and TIS in combination demonstrated a greater ability to optimize the intestinal microbiota of A. japonicus by increasing the potentially beneficial bacteria involved in energy production and biosynthesis, and suppressing the opportunistic pathogens. These results collectively indicated that the combined supplementation of L. acidophilus and TIS has a synergistic effect on enhancing immunity and digestibility, and could improve the intestinal microbiota structure of A. japonicus, suggesting potential for industrial feeding applications.

Effect of dietary protein level on growth, food utilization, food conversion and survival rate of giant trevally (Caranx ignobilis)

Background: Proper feed formulation is required for successful fish farming activities. Therefore, it is necessary for fish feed to provide optimal growth so that the cultivation business generates profits. Currently, there is very limited information about the appropriate feed for Caranx ignobilis, causing problems with its development. This study aims to provide feed with different protein levels to C. ignobilis. Methods: We will examine the protein levels’ effects on the daily growth rate (DGR), specific growth rate (SGR), absolute growth rate (AGR), feed conversion ratio (FCR), feed efficiency (FE), and survival rate (SR). This research was conducted for 35 days, from June to October 2017, at the Center Brackiswater Aquaculture Development (BPBAP) Ujung Batee, Ministry of Marine Affairs and Fisheries, Aceh Besar, Indonesia. This study used a completely randomized design method, with five treatment levels (30%, 40%, 50%, 60%, and 70% protein feed) and four replications. Results: The results showed that feeding with different proteins on C. ignobilis had a significant effect on the mean values ​​of DGR, SGR, AGR, FCR, FE, and SR. The 50% protein feed gave the best results for C. ignobilis, with a mean DGR value of 0.267 ± 0.005 g / day, a mean SGR of 1.722 ± 0.030% / day, a mean AGR of 0.081 ± 0.003 cm/day, a mean FCR of 1.290, a mean FE 77.755% and a mean SR was 86.667%. Conclusions: Furthermore, feed treatment with increased protein content between 30%–50% has a positive correlation with the growth of C. ignobilis. However, the ability to grow fish will decrease if the feed protein content is &gt;50%.

Therapeutic effects of chitin from Pleurotus eryngii on high-fat diet induced obesity in rats.

Recent shifts in lifestyles and diets have caused the incidence of obesity to increase rapidly, resulting in a serious threat to modern human health. There is a growing interest the use of plant or fungi derived supplements as a safe and effective means to treat obesity. In recent times, edible-medicinal fungi have garnered attention as therapeutics owing to their biocompatibility and effectiveness. Attempts to determine the therapeutic effects of these fungi have become a prime focus in drug discovery programs. Therefore, this study aimed to determine the anti-obesity effects of P. eryngii chitin in rats with obesity induced by administration of a high fat diet. To investigate the therapeutic effects of chitin from Pleurotus eryngii on high fat diet-induce obesity, we treated obese rats with different concentrations of chitin from P. eryngii for 4 weeks, using Lipitor as positive control. The living condition, food intake, body weight, perirenal adipose tissue, periepididymal adipose tissue, adipose tissue coefficient, serum lipid levels, including total cholesterol (TC), total glyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), were measured, and levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), themalonaldehyde (MDA), and superoxide dismutase (SOD) activity in liver were determined. The rats were also monitored for pathological changes in the liver and aorta. These studies indicated that administration of chitin from P. eryngii could significantly decrease obese rat food utilization rates and accumulation of adipose tissue in the body, thus preventing development of increased body weight. The treatment also significantly reduced serum lipid levels, including levels of TC, TG and LDL-C. Treatment with P. eryngii-derived chitin also enhanced ALT and AST enzymatic activity, enhanced SOD enzymatic activity, and reduced the MDA content of the liver, as well as significantly reducing the liver index and alleviating liver steatosis and aortic atherosclerosis resulting from obesity. In conclusion, chitin from P. eryngii had therapeutic effects on hyperlipidemia, fatty liver, and aortic atherosclerosis resulting from obesity in rats.

Effect of Tannic Acid on Nutrition and Activities of Detoxification Enzymes and Acetylcholinesterase of the Fall Webworm (Lepidoptera: Arctiidae).

Plant tannins, polyphenolic plant secondary metabolites are involved in important chemical defense processes in plants. In this study, tannic acid was used as the standard of plant tannins to determine the effects on nutritional indices and activities of glutathione S-transferases (GSTs), cytochrome P450 monooxygenase (CYP450), carboxylesterase (CarE), and acetylcholinesterase (AChE) in fourth-instar larvae of Hyphantria cunea (Drury) by feeding on an artificial diet containing tannic acid under different treatments. We found that tannic acid significantly affected the digestive capacity and food utilization rate of H. cunea larvae. A tannic acid concentration of less than 2.0% promoted feeding and the utilization of undesirable food by H. cunea larvae, while inhibitory effects were observed at high concentrations (>2.5%). Tannic acid had a significant effect on the activity of detoxification enzymes and AChE in H. cunea larvae in concentration-dependent and time-dependent manners (P < 0.05). These results provide new insights into the potential mechanisms underlying detoxification in H. cunea larvae against tannic acid in host plants.

Subchronic toxicity of huanghuali tea in rats

Objective To assess subchronic toxicity of huanghuali ( Dalbergia odorifera T. Chen ) tea in rats. Methods A ninety-day feeding experiment was performed in 140 specific pathogen free Sprague-Dawley (SD) rats according to the Food Safety Toxicology Evaluation Procedures and Methods – 2015 Edition. Results During the experiment, all the rats were generally in good condition and no death was observed. Compared with those of the control rats, there was no significant difference in weekly body weight, food intake and food utilization rate of final phase, hematology and serum biochemical indexes, organ weight and organ/body weight ratio in rats of all the dose groups ( P > 0.05). No remarkable changes were observed in urinary routine indicators, eye examination and gross anatomy, and histopathological examinations. Conclusion Huanghuali tea shows no obvious toxicity, with a no observed adverse effect level (NOAEL) of 22.22 g/kg·bw, in rats. 【摘 要】 目的 探讨黄花梨茶对大鼠的亚慢性毒性作用。 方法 参照 2015 版《食品安全性毒理学评价程序和方法》中的 90 d 喂养试验方法对黄花梨茶的亚慢性毒性进行分析。 结果 试验观察期间大鼠一般状态良好，无死亡；与对照组比较，各剂量黄花梨茶组大鼠体重、进食量和食物利用率、动物血液学和血清生化指标以及脏器重量及脏器/体重比值无明显变化，差异均无统计学意义（ P > 0.05）；尿常规指标、眼部检查及大体解剖和组织病理检查未见明显与受试物有关的异常改变。 结论 黄花梨茶对大鼠无明显亚慢性毒性作用，最大未观察到有害作用剂量（NOAEL）为 22.22 g/kg。

Food Policy and Household Food Waste

AbstractReducing household food waste is an important policy objective. In this paper we examine how equilibrium food waste among households is influenced by food policies designed to increase household food utilization and to alter household food purchasing behavior by adjusting market prices. We demonstrate that policies that reduce the marginal cost of household food utilization and that raise fresh food prices result in greater food waste for households with sufficiently price‐elastic demand for fresh food. Policies that raise the processed food prices increase fresh food consumption, but nevertheless reduce food waste, provided that fresh and processed foods are substitutes in utility and the equilibrium food utilization rate in a household is sufficiently high.

Food utilization and excretion mechanism of Cd in gypsy moth larvae fed on Cd-enriched Populus albaXP. berolinensis leaves

To investigate the eco-physiological responses of phytophagous insects to host plants exposed to heavy metal stress, the gypsy moth (Lymantria dispar) larvae were reared with leaves of Populus albaXP. berolinensis grown in Cd-contaminated soil to analyze their food utilization and mechanisms underlying Cd excretion. Our results showed that after feeding on Cd-stressed poplar leaves, Cd concentrations and contents in the 3rd-6th instar larvae were significantly higher than those in control. The Cd concentrations significantly decreased with the larval age, whereas it was reverse for Cd contents. Cd concentrations in the larval faces and exuvia were significantly higher than those in control. Food digestion/consumption rate and conversion rate of the 3rd-5th instar larvae in the Cd-treatment group were significantly higher and lower than those in the control, respectively. Food utilization rate of the Cd-stressed 3rd-4th instar larvae were not significantly different from that of the control larvae with the same age. In contrast, the Cd-stressed 5th instar larvae showed a significantly lower food utilization rate than the control. These results indicated that gypsy moth larvae could remove some Cd from their bodies through effective excretion (e.g. feces and exuvia), with the mature larvae being more effective than the juveniles. The increases of larval body mass seemed to have a "dilution effect" on its Cd concentration. Under Cd stress, the gypsy moth larvae might maintain a certain level of food utilization rate for growth and development via a modulation of food consumption/conversion rates, but Cd-stress would still reduce the larval food utilization rate when it was beyond a certain threshold.

Intervention effect of gamma aminobutyric acid on anxiety behavior induced by phthalate (2-ethylhexyl ester) in rats

ABSTRACTBackground: Di(2-ethylhexyl) phthalate (DEHP) is one of the most widely used phthalate esters. The application of DEHP has caused serious environmental pollution and posed a threat to human health.Methods: A total of 30 male Sprague-Dawley rats were randomly divided into control group, DEHP group (500 mg/kg DEHP), low GABA (Gama-aminobutyric acid) group (500 mg/kg DEHP and 1 mg/kg GABA), medium GABA group (500 mg/kg DEHP and 2 mg/kg GABA) and high GABA group (500 mg/kg DEHP and 4 mg/kg GABA). The interventions continued for 30 consecutive days. Open-field test and elevated plus-maze test were used to detect behavioral changes of rats before and after interventions.Results: The levels of nitric oxide and nitric oxide synthase in prefrontal cortex of rats were measured using enzyme-linked immunosorbent assay. DEHP and GABA treatment had no significant effects on the body weight of rats. GABA restored food utilization rate of rats impaired by DEHP to the level of healthy rats. According to open-field test and elevated plus-maze test, GABA alleviated the effects of DEHP on rat behaviors. Enzyme-linked immunosorbent assay showed that GABA was effective in reducing the levels of nitric oxide and nitric oxide synthase in rats treated with DEHP.Conclusion: DEHP exposure induced anxiety in rats, which may be achieved through elevating nitric oxide and nitric oxide synthase levels in prefrontal cortex of rats. However, the effects caused by DEHP could be alleviated by GABA.

Cow Urine Distillate as an Ecosafe and Economical Feed Additive for Enhancing Growth, Food Utilization and Survival Rate in Rohu, Labeo rohita (Hamilton)

Cow Urine Distillate as an Ecosafe and Economical Feed Additive for Enhancing Growth, Food Utilization and Survival Rate in Rohu, Labeo rohita (Hamilton)

Long-term effect of iodine deficiency on growth and food utilization rate in second filial generation rats

Objective: To study the effect of iodine deficiency on body weight, food consumption, and food utilization rate of second filial generation Wistar rats. Methods: According to the food pattern of a high-iodine deficient population, two types of low-iodine food have been produced using the main crops grown in this area (iodine levels of 50 and 20 μg/kg, respectively). Wistar rats were randomly divided into three groups, normal iodine group (NI group), low-iodine group one (LI group) and low-iodine group two (LII group), using the random number table method and fed diets containing 300, 50, and 20 μg/kg of iodine, respectively. Parental generation rats were fed until they reached reproductive age; first filial generation rats were allocated to the same diet as their mothers. After 3 months of feeding, first filial generation rats gave birth to second filial generation rats; second filial generation rats were allocated to the same diet as their mothers. After feeding for 90, 180, and 270 days, rats were sacrificed. One-way analysis of variance was used to analyze body weight, food intake, and food utilization rate data collected during the time of feeding and blood iodine hormone level, which was determined after sacrifice. Results: The LI and LII groups generally demonstrated decreased activity, slow reaction, and growth retardation compared with the NI group. After 270 days, the urine iodine levels of the LI and LII groups were 1.7 and 0.2 μg/L, respectively, which were significantly lower than the NI group (255.2 μg/L) (P<0.001). Additionally, the weight of female rats in the LI and LII groups were (288.1±10.5) and (275.7±2.7) g, respectively, which was significantly lower than that of the NI group ((311.0±2.3) g) (P<0.001). The weight of male rats were (446.0±4.6) and (451.8±19.1) g, respectively, which were significantly lower than that of the NI group ((517.2±7.8) g) (P<0.001). In the LI and LII groups, food intake of female and male rats after 270 days were (465.0±27.7), (658.4±28.6) and (423.0±13.2), (548.0±18.8) g, respectively, which were significantly lower than that of the NI group ((499.5±21.8), (760.8±33.0) g) (P<0.001). Moreover, the food utilization rate of female rats in the LI and LII groups was (8.7±0.4)% and (6.0±0.58)%, which was lower than that of the NI group ((11.7±3.5)%) (P<0.001); similarly, male rats showed rates of (8.9±1.5)% and (6.9±1.31)%, respectively, which were lower than that of the NI group ((13.7±3.0)%) (P<0.001). After 270 days, the level of T3 in the LI and LII groups were (0.45±0.10) and (0.34±0.15) ng/ml, respectively, which was significantly lower than that of the NI group ((0.91±0.49) ng/ml) (P<0.01). Moreover, the level of T4 were (69.02±27.87) , (53.18±13.53) ng/ml in LI and LII groups, respectively, which was lower than that of the NI group ((76.69±29.42) ng/ml) (P<0.05). Conclusion: This study indicated that iodine deficiency induced by a long-term low-iodine diet can cause changes in weight, food intake, and food utilization rate among second filial iodine deficiency rats. More importantly, the iodine content in low-iodine food impacts these parameters.

Intermittent exercise improves the vasoreactivity of the thoracic aorta in rats.

Vasoreactivity is the most basic and direct indicator to reflect the artery vascular functional state in the body. The majority of previous studies have shown that a high-fat diet (HD) is often associated with a variety of cardiovascular diseases. However, the type of exercise that improves vasoreactivity, as is induced by a HD, remains to be elucidated. In the present study, the effects of aerobic moderate-intensity intermittent exercise through swimming were investigated on thoracic aorta vascular ring contraction and free radical metabolism using Sprague-Dawley rat models of common diet (CD; 23 g protein, 49 g carbohydrate, 4 g fat, 5 g fiber, 7 g bone meal and 6 g vitamins per 100 g), HD (peanuts, milk chocolate and sweet biscuits, in a weight ratio of 3:2:2:1), CD with intermittent exercise (CIE) and HD with intermittent exercise (HIE). The food utilization rate in the swimming group (CIE) decreased in comparison with the CD group. Lee's index in the CIE group decreased in comparison to that of CD after 8 weeks (P<0.05) and also HIE decreased compared to HD (P<0.05) after 8 weeks. Compared with the HD group, contractile response of the thoracic aortic rings to NA decreased in the HIE group, while high-density lipoprotein cholesterol content increased, total cholesterol, triglycerides and low-density lipoprotein cholesterol decreased (P<0.05); the malondialdehyde (MDA) concentration reduced in the myocardium, but the superoxide dismutase (SOD) level improved (P<0.05). In the HIE group, nitric oxide level was similar to the CD group. Compared with CD, contractile response of the thoracic aortic rings to NA increased in the CIE (P<0.05), the MDA concentration reduced in the myocardium, but the SOD level improved (P<0.05). Tunica media smooth muscle of the thoracic aortic rings in the CIE group arranged more regularly in comparison with the CD group (without swimming training). In conclusion, intermittent exercise improves the thoracic aorta vasoreactivity and function by enhanced antioxidant enzyme activity and reduced free radical generating.