One-electron reduction potentials of dietary carotenoid radical cations in aqueous micellar environments

The one-electron reduction potentials of the radical cations of five dietary carotenoids (β-carotene, canthaxanthin, zeaxanthin, astaxanthin and lycopene) in aqueous micellar environments have been obtained from a pulse radiolysis study of electron transfer between the carotenoids and tryptophan radical cations as a function of pH, and lie in the range of 980–1060 mV. These values are consistent with our observation that the carotenoid radical cations oxidise tyrosine and cysteine. The decays of the carotenoid radical cations in the absence of added reactants suggest a distribution of exponential lifetimes. The radicals persist for up to about 1 s, depending on the medium.     

Effects of providing dietary wood (oak) charcoal to broiler chicks and laying hens

Three experiments were carried out to determine whether dietary wood (oak) charcoal applied during entire or phase feeding period would affect growth performance, abdominal fat weight, carcass weight, carcass yield, carcass composition and nutrient excretion of broilers and to determine whether dietary wood charcoal supplementation would affect laying performance and egg quality of laying hens. In the first experiment, different inclusion levels (0, 25, 50 and 100 g/kg feed) of wood charcoal in the diet were examined for a 6-week-period using broiler chicks of initial age 1 week. Dietary wood charcoal significantly increased feed intake (P<0.001), body weight gain (P<0.001) and improved feed conversion ratio (P<0.05) up to 28 days of age. However, at 49 days of age, charcoal inclusion did not significantly (P>0.05) affect body weight gain, feed intake, carcass weight and carcass yield, but increased (P<0.05) feed conversion ratio, carcass ash content, fat excretion, while reducing (P<0.05) mineral excretion in a dose dependent manner. In the second experiment, a phase application of dietary wood charcoal for a 6-week-period broiler chicks of initial age 1 week was assessed. During the first 28 days of age wood charcoal improved feed conversion ratio significantly (P<0.05). At 49 days of age, the groups receiving charcoal in the starter and/or finisher diets showed significantly (P<0.05) higher body weight gain and carcass weight than the control group receiving no charcoal. In the third experiment, different levels (0, 10, 20 and 40 g/kg feed) of wood charcoal supplementation to a layer diet were examined for a 7-week-period using laying hens of initial age 34 weeks. Dietary charcoal supplementation did not have a significant effect on any parameters related to performance and egg quality, but significantly reduced number of cracked eggs and the reduction was dose dependent (P<0.01). These data demonstrate that wood charcoal inclusion to the diet could be of value in improving broiler performance during the first 28 days of fattening period. In later ages, the positive effects of wood charcoal are limited. However, in laying hens dietary supplementation of wood charcoal reduces number of cracked eggs.     

Observations of Size-related Asymmetries in Diet and Energy Intake of Rainbow Trout in a Regulated River

We examined diet and diel energy intake of rainbow trout, Oncorhynchus mykiss, of different lengths captured by electrofishing between 1991 and 1997 in the Lee's Ferry tailwater, Colorado River, below Glen Canyon Dam, Arizona. Trout diets reflected a depauperate food base and indicated limited potential of different fish size-groups to partition food resources. As evidenced by relative stomach volumes of ingested matter, mid-sized and large trout tended to consume more algae than did small fish, suggesting that they consumed diets of lower nutritional quality. An energy intake model indicated that median consumers among mid-sized and large fish generally failed annually to surpass estimated maintenance energy requirements and that median consumers among mid-sized trout failed to meet or exceed maintenance requirements during all seasons. In contrast, median consumers among small trout met or surpassed maintenance energy requirements during most years and in summer. Results support a hypothesis that larger rainbow trout in lotic systems are food-limited more often than smaller fish.     

内蒙古库布齐沙地黑线仓鼠食物构成的季节变化

黑线仓鼠 (Ｃｒｉｃｅｔｕｌｕｓｂａｒａｂｅｎｓｉｓ)是广泛分布于我国华北和中原地区草原、农田的一种农牧业害鼠[8] ,在这些生境中 ,其食物以各种农作物和牧草种子为主 ,并取食大量昆虫[1,3 ,5,6 ] 。在鄂尔多斯高原库布齐沙地环境中 ,由于该种耐受高温环境的能力相对较低 ,仅分布在郁蔽程度较高的固定沙地和农田。研究表明 ,本地区该种的数量近年呈上升趋势[2 ] 。结合研究其数量变动规律 ,我们于 1996年 4～ 10月对其食物构成的季节变化进行了研究 ,以分析其生态适应对策。1　研究方法研究点设在库布齐沙地东段的中国农业科学院草原研…     

Diet composition and feeding ecology of the naked goby Gobiosoma bosc (Gobiidae) from four western Atlantic estuaries

The feeding ecology of the small‐bodied benthic naked goby Gobiosoma bosc, a western Atlantic species that occurs in estuaries and other inshore habitats from Connecticut to Texas U.S.A., was investigated in a total of four estuaries spanning South Carolina, North Carolina, Maryland and New Jersey. Gut content analysis of 391 individuals revealed that G. bosc is a benthic microcarnivore that feeds primarily on polychaetes, gammarid amphipods and harpacticoid copepods. Diet composition varied with body size, tidal creek within an estuary and geographic region. Analyses of gut fullness suggest that G. bosc is a daytime visual predator and that nest and egg guarding during the reproductive season reduce foraging activity in mature males. Additionally, G. bosc infected with adult digenean parasites of the gut foraged more intensely than uninfected individuals, a relationship that was strongest for reproductively mature males. Regionally, significant variation in dietary breadth was documented and may reflect a foraging response to a decrease in prey diversity moving from estuaries of higher salinity and lower latitude to estuaries of lower salinity and higher latitude. These results contribute to an understanding of the life history of G. bosc and the role played by this common species in estuarine food webs.     

Long-term feeding on powdered food causes hyperglycemia and signs of systemic illness in mice

Aims

Dietary habits are crucial factors affecting metabolic homeostasis. However, few animal experiments have addressed the effects of long-term feeding with soft food on parameters reflecting systemic health.

Main methods

Using mice, we compared the effects of short (3 days) and long (17 weeks from weaning) feeding periods between powdered food and normal pellet food on the levels of blood glucose, serum levels of insulin, catecholamines, and corticosterone, blood pressure, and/or social interaction behaviors. In addition, the effects of a human glucagon-like peptide-1 analog, liraglutide (a new drug with protective effects against neuronal and cardiovascular diseases), were compared between the powder and pellet groups.

Key finding

(i) Powdered food, even for such a short period, resulted in a greater glycemic response than pellet food, consistent with powdered food being more easily digested and absorbed. (ii) Long-term feeding on powdered food induced hyperglycemia and related systemic signs of illness, including increases in serum adrenaline, noradrenaline, and corticosterone, higher blood pressures (especially diastolic), and increased social interaction behaviors. (iii) Liraglutide, when administered subcutaneously for the last 2 weeks of the 17-week period of feeding, improved these changes (including those in social interaction behaviors).

Significance

The hyperglycemia associated with long-term powdered-food feeding may lead to certain systemic illness signs, such as elevations of blood glucose, hypertension, and abnormal behaviors in mice. Mastication of food of adequate hardness may be very important for the maintenance of systemic (physical and mental) health, possibly via reduction in the levels of blood glucose and/or adrenal stress hormones (catecholamines and glucocorticoids).     

Dietary zinc intake,supplemental zinc intake and serum zinc levels and the prevalence of kidney stones in adults

ObjectiveThe association between zinc intake and the risk of kidney stones remains controversial. We examined the associations between dietary zinc intake, supplemental zinc intake and serum zinc levels and the prevalence of kidney stones in adults.MethodsAdult participants from the 2007–2016 NHANES were included. Restricted cubic splines were adopted to assess the dose-response relationships.ResultsDietary zinc intake was linearly associated with the prevalence of kidney stones (P_{for non-linearity} = 0.50), and the odds ratios (95% confidence intervals) of kidney stones were 0.75 (0.51–1.04) for 10 mg/day, 0.65 (0.39-0.97) for 20 mg/day, 0.53 (0.30-0.94) for 30 mg/day and 0.45 (0.22-0.95) for 40 mg/day. The linear relationship was also observed among women and overweight/obese individuals. No association was found between supplemental zinc intake and the prevalence of kidney stones. A non-linear relationship was found between serum zinc levels and the prevalence of kidney stones (P_{for non-linearity} = 0.02), and the odds ratios (95% confidence intervals) of kidney stones were 0.52 (0.33-0.82) for 70 ug/dL, 0.43 (0.24-0.77) for 90 ug/dL, 0.56 (0.32-0.98) for 110 ug/dL and 0.77 (0.37–1.62) for 130 ug/dL. The non-linear relationship was also observed among men and overweight/obese individuals.ConclusionsDietary zinc intake and serum zinc levels were inversely associated with the prevalence of kidney stones in adults, and there may be effect modification by participant sex and body mass index. The present analysis is limited in its ability to establish causality.     

高血压患者饮食习惯、传统制剂服用现状调查及其影响因素分析

目的:调查高血压患者饮食习惯以及传统制剂服用现状,并分析饮食习惯与高血压患病的关系以及传统制剂服用的影响因素。方法:按照简单随机抽样法,采用自制调查问卷对呼和浩特市3个镇共8个行政村成年常住农村村民进行问卷调查,调查内容包括人口学特征、饮食习惯等内容,并采用多因素logistic回归分析饮食习惯与高血压患病的关系以及高血压患者传统制剂服用的影响因素。结果:呼和浩特市高血压患病率为22.68%。多因素logistic回归结果显示,较高的BMI、高血压家族史、饮酒史、泡菜咸菜、油炸食品、红肉(猪/牛/羊肉)/动物内脏、海产品是高血压独立危险因素(OR=1.257、1.451、1.358、1.317、1.108、1.146、1.373,P<0.05),奶制品、豆制品、新鲜果蔬是高血压保护因素(OR=0.797、0.868、0.903,P<0.05)。高血压患者传统制剂服用率为16.90%。多因素logistic回归结果显示,年龄≥60岁、文化程度高中以下、不了解高血压知识是高血压患者传统制剂服用的危险因素(OR=1.342、1.545、1.142,P<0.05)。结论:呼和浩特市农村成年村民高血压患病率较高,不良饮食习惯(饮食偏咸、油腻等)是高血压独立危险因素,高龄、文化程度低、不了解高血压知识的高血压患者传统制剂服用率较高,应加强农村居民合理膳食、保持均衡饮食习惯的宣传教育以及农村高血压患者用药规范。     

Shifts of food habit and jaw position of white-spotted charr after damming

Stomach fullness of white-spotted charr, Salvelinus leucomaenis did not differ significantly between above-dam (allopatric with masu salmon) and below-dam (sympatric with masu salmon) areas, but stomach contents did. Juveniles (1+) below the dam consumed relatively more aquatic insects (benthic prey), and those above the dam consumed relatively more terrestrial insects (drifting prey), but there was no difference in the diet of >2+ fish between areas. The mouths of juveniles above the dam were more terminal than those of fish below the dam. The adaptive significance of these differences is discussed in relation to differences in fish assemblages. 1999 The Fisheries Society of the British Isles     

Summer feeding habits of the Pacific pomfret Brama japonica in the transitional and subarctic waters of the central North Pacific

Feeding habits of the Pacific pomfret Brama japonica , ranging from 30 to 40 cm in standard length, were quantitatively evaluated using the index of relative importance and were compared between the transitional domain and subarctic region in the central North Pacific. In the transitional domain (between the subarctic boundary and the subarctic front), this species fed mainly on subarctic and transitional‐water gonatid squids such as Berryteuthis anonychus , Gonatus middendorffi and Gonatopsis borealis , the transitional‐water squid Onychoteuthis borealijaponica , and a subtropical and transitional‐water amphipod, Phronima sedentaria . These prey items accounted for 52·8% by wet mass of total stomach contents. In the subarctic region (north of the subarctic front), Pacific pomfrets preyed primarily on subarctic and transitional‐water squids, such as B. anonychus and G. middendorffi , and secondarily on subarctic amphipods such as Hyperia medusarum and Hyperia glaba . These four prey items comprised 71·6% by mass of total stomach contents. Major transitional domain prey items, such as G. borealis, O. borealijaponica and P. sedentaria , were almost non‐existent in stomachs of fish from the subarctic region. The mean wet stomach content mass expressed as a percentage of body mass was significantly higher in the subarctic region (2·35%) than in the transitional domain (0·75%), suggesting that, for this fish, prey items are more readily available in the subarctic region during summer and their northward migration is a feeding migration. Feeding strategy of the Pacific pomfret was discussed in relation to their seasonal south‐north migration.