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1.
1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 or 0.4 g/kg or beta-aminopropionitrile fumarate at 0.5 or 0.6 g/kg diet to examine their effects on eggshell quality. 2. Shell quality characteristics considered for evaluation were shell surface area, shell thickness, shell weight, percentage shell, shape index and the specific gravity of eggs. Measurement of shell quality traits revealed that the hens fed osteolathyrogens laid eggs with significantly lower specific gravities and proportion of shell by weight. These differences were not explained by differences in shell thickness or weight or the shape index of eggs. 3. It was concluded that osteolathyrogens cause hens to lay eggs with poor shell quality and such eggs are weak and fragile.  相似文献   

2.
The influence of some frequent dietary constituents on gastrointestinal absorption of aluminum from drinking water and diet was investigated in mice. Eight groups of male mice received lactic (57.6 mg/kg/day), tartaric (96 mg/kg/day), gluconic (125.4 mg/kg/day), malic (85.8 mg/kg/day), succinic (75.6 mg/kg/day), ascorbic (112.6 mg/kg/day), citric (124 mg/kg/day), and oxalic (80.6 mg/kg/day) acids in the drinking water for one month. At the end of this period, animals were killed and aluminum concentrations in liver, spleen, kidney, brain, and bone were determined. All the dietary constituents significantly increased the aluminum levels in bone, whereas brain aluminum concentrations were also raised by the intake of lactic, gluconic, malic, citric, and oxalic acids. The levels of aluminum found in spleen were significantly increased by gluconic and ascorbic acids, whereas gluconic and oxalic acids also raised the concentrations of aluminum found in kidneys. Because of the wide presence and consumption of the above dietary constituents, in order to prevent aluminum accumulation and toxicity we suggest a drastic limitation of human exposure to aluminum.  相似文献   

3.
Twenty-one samples of water were collected from commercial egg production farms in Georgial with or without a history of fatty liver syndrome. These samples plus a sample of water from the University of Georgia Poultry Farm were analyzed for various mineral elements by atomic absorption, direct reading emission spectroscopy and by neutron activation. Water samples from farms with a history of fatty liver syndrome had signficantly more calcium, magnesium, strontium, sodium, iron and barium than water samples from farms reporting no significant problem with fatty liver syndrome. Levels of manganese, boron, copper zinic and aluminum were not significantly different. Although the results do not prove that water quality is the cause of the disease, they do demonstrate an association of hardness of water with fatty liver syndrome that should be further investigated.  相似文献   

4.
Solutions of neurotensin (NT) at 0, 12, 60, 120, and 600 nM were infused i.v. into anesthetized, 16- to 34-wk-old hens at 60 microL/kg per minute for 30 min. These infusates increased plasma NT concentrations to steady state values of about .1, .2, 1, 2, and 10 times the postprandial concentrations of NT in hepatic portal blood, respectively. None of these concentrations significantly affected heart rate or arterial (carotid) or central venous (jugular) blood pressure.  相似文献   

5.
The effects of L-carnitine supplementation (50-500 mg/kg diet) of a practical layer diet, based on maize, soyabean and wheat, on the performance of laying hens and some indices of egg quality were studied for 8 weeks, using 65-week-old hens kept in cages. Albumen quality (albumen height and Haugh (1937) unit score) was improved, while yolk index and yolk colour score were not affected by dietary L-carnitine. The percentage of egg-white increased and that of egg yolk decreased in response to dietary supplementation of L-carnitine. Dietary L-carnitine did not influence laying performance (egg production rate, mean egg weight, daily feed intake, daily egg mas and feed conversion) or external egg quality measured by egg weight, egg-shape index or by eggshell quality, either measured directly as shell breaking strength or indirectly as shell weight, shell thickness or shell weight per unit surface area. Based on the results of the present study, L-carnitine had a beneficial effect on albumen quality and could modify the components of the edible part of the egg, during the late laying period.  相似文献   

6.
The importance of the length of the rest period and of photoperiod as components of the forced molt procedures was evaluated in 650- and 560-d-old Lohman hens. The procedure included an 8-d feed withdrawal phase and rest periods varying from 0 to 35 d, during which the birds were fed for maintenance only. In the first trial, forced molt was applied with or without omission of artificial illumination. The rest period varied between 2 and 20 d. In the second trial, all treatments included omission of artificial illumination, and a variable rest period between 0 and 35 d. Egg production ceased, after 4 to 5 d of feed withdrawal and resumed 8 to 15 d after the end of the rest period, without any consistent response to its length. Forced molt stimulated egg production rate and diminished its age-dependent rate of decline, reduced the proportion of broken and shell-less eggs, and improved shell quality. Following wide oscillations proportional to the length of the rest period, egg weight stabilized at levels similar to that of the unmolted controls. Feed intake was stimulated by forced molt to levels exceeding those of the control hens. Body weight increased during the postmolt period to levels slightly exceeding those of unmolted controls. Results of one trial show that omission of artificial illumination was essential for the full expression of the molt responses. In the other trial, production rate and shell quality were improved and the percentage of broken eggs was reduced when the length of the rest period was increased. Maximal improvements appears to have been reached with rests period of 14 to 21 d.  相似文献   

7.
High field intensity magnetic resonance imaging (HF-MRI) has been applied to the in vivo study of age-related processes of organs located in the cervical-thoracic region in mice and to describe the effects of oral zinc supplementation on these processes. Spin-echo (SE) pulse sequence and chemical shift imaging (CSI) techniques have been used. Aging produced a progressive reduction of muscular masses and of thymic area, whereas the HF-MRI appearances of spinal cord and of salivary glands were unchanged. In some aged animals, subcutaneous fat was reduced while visceral fat was well developed. In the group of old animals supplemented with zinc sulphate, muscular masses were more developed than that of the group of untreated old animals. Oral zinc supplementation also produced an enlargement of the adipose tissue and the thymic area showed an increase of about 65% compared with thymic area measured in the group of old animals used as controls. The present study confirms previous data about the effects of Zn supplementation on aging processes and demonstrates that HF-MRI is a powerful technique to study processes of aging, providing information about the effects of drug treatments on these processes.  相似文献   

8.
Previous studies show that desalivate (DS) rats drink more water than controls when maintained on a diet of dry food, but drink less than controls after a period of water deprivation. In the present series of studies, a total of 14 male and 2 female naive hooded rats served as Ss. Results show that DSs ate less food than sham operates (SHs), indicating that DSs' body fluids probably do not become as hyperosmotic as those of the SHs. When Ss were maintained on a moist mash during water deprivation, subsequent water intake and air licking were about the same for DSs and SHs. After combined food and water deprivation, both groups air-licked at greatly reduced rates. After subcutaneous injections of hypertonic saline, DSs air-licked just as much as SHs. It is concluded that DSs drink less after water deprivation because they eat less dry food than SHs during deprivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Energy requirements of grazing livestock seem to be poorly defined. Requirements generated from measurements in pen-fed animals present both theoretical and practical concerns when they are applied to grazing situations. In mature ruminants a majority of energy used for maintenance seems to be consumed by visceral tissues. Moreover, factors that affect visceral energy use are poorly understood. Energy supplementation to meet requirements and production demands is often practiced during periods of summer dormancy and in winter months. Source of supplemental energy varies widely and includes grains, readily digestible fiber sources, and high-quality forages. Intake and digestibility can be reduced or unaffected by energy supplementation. In some cases, lower levels of energy supplementation have been shown to increase utilization of grazed forage. Reductions in ruminal pH, often cited as the major cause of reduced fiber digestion, may not always explain reductions in intake and digestibility associated with energy supplementation. Livestock production is usually either enhanced or unaffected by energy supplementation. Additional research regarding energy requirements of grazing ruminants, visceral energy use, and mechanisms associated with reductions in intake and digestibility of grazed forage resulting from energy supplementation is warranted.  相似文献   

10.
Nine resistance-trained men consumed either a protein-carbohydrate supplement or placebo for 1 wk in a crossover design separated by 7 days. The last 3 days of each treatment, subjects performed resistance exercise. The supplement was consumed 2 h before and immediately after the workout, and blood was obtained before and after exercise (0, 15, 30, 45, and 60 min postexercise). Lactate, growth hormone, and testosterone were significantly (P 相似文献   

11.
1. Three sequential experiments, each lasting 8 weeks, were carried out on 576 singly-caged light hybrids. 2. In experiment 1 egg production was 84% using a conventional control diet, 61% with a basal low-protein diet, and 79% with the basal diet supplemented with 10 essential amino acids+L-glutamic acid (GA). 3. In experiment 2 supplementation with lysine and methionine (L+M) alone increased egg production significantly from 54 to 72%, compared with 83% with the conventional diet. 4. In experiment 3 egg production was 55% with the basal diet, 71% with the basal diet+L+M, 75% with a diet containing 141 g protein/kg+L+M, and 73% with the conventional diet. 5. In all three experiments supplementation with GA alone either gave no significant response or a depression in production. 6. Daily intakes of 1-24 g nitrogen as non-essential amino acids and 13 to 14 g total crude protein per bird resulted in good egg production. Supplementation of the basal diet with L+M resulted in a daily intake of 413 mg methionine/bird day which was considered adequate, and a daily intake of 710 mg lysine which was considered slightly inadequate.  相似文献   

12.
The ethyl esters of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were added to a broiler starter diet singly or in combination [as bulk purified ethyl ester concentrate from menhaden oil (n3FAC)] in quantities similar to those found in a diet supplemented with 5% menhaden oil (MO). Diets were fed to chickens from 1 d of age through 3 wk of age. At 2 wk of age, the chickens were infected with Eimeria tenella, Eimeria acervulina, or Eimeria maxima. At 6 d postinfection (PI), the effects of the diets were assessed on weight gains, plasma carotenoids, gross lesion scores, and histological parasite scores in gut cross sections, or oocyst output. Significant ameliorating effects of diet on lesion scores and parasite scores were only seen in E. tenella infections and were only produced by the n3FAC and MO supplements. These two supplements, which contained higher molar concentrations of double bonds than the other supplements, also significantly reduced plasma carotenoids in uninfected chickens, indicating that they promoted a state of oxidative stress. These results are consistent with previous reports on the interaction of coccidiosis with dietary n-3 fatty acids and strengthen the hypotheses that dietary-induced oxidative stress is an effective deterrent against cecal coccidiosis in chickens.  相似文献   

13.
BACKGROUND: It has been theorized that fetal myelomeningocele repair may reduce ongoing intrauterine injury and perhaps allow healing and regeneration of dysplastic neural tissue. We report on the postnatal imaging studies of the first 4 patients to have undergone intrauterine myelomeningocele repair at our institution. METHODS: Each of the 4 patients underwent postnatal sonographic and MRI. In addition, the postnatal ultrasounds of these 4 were compared to a group of retrospective controls. RESULTS: MRI scans of the 4 experimental subjects revealed no evidence of hindbrain herniation while other stigmata of the Chiari-II malformation persisted. In comparison to the retrospective controls this absence of herniation was distinctly unusual. CONCLUSION: Intrauterine myelomeningocele repair may reduce the degree of hindbrain herniation normally seen in patients with myelomeningocele. This raises the possibility that intrauterine repair may decrease the morbidity associated with the Chiari type-II malformation including brainstem dysfunction, hydrocephalus and syringomyelia.  相似文献   

14.
Two experiments were conducted to determine the effect of dietary linoleic to linolenic acid (LO:LN) ratio and dl-alpha-tocopheryl acetate (TA) supplementation on selected characteristics of the liver and cerebellum and on vitamin E status of turkey poults from hatch through 22 d of age. In Experiment 1, 1-d-old poults were fed diets containing no supplemental TA (0E) or 150 IU TA/kg diet (150E). Poults fed the 150E diet had greater (P < 0.001) concentrations of alpha-tocopherol (TOC) in the liver and plasma than those fed the 0E diet from 7 to 22 d of age. The 150E diet, however, did not completely overcome the decrease in liver and plasma TOC concentrations observed at these ages. The 150E diet had no effect on poult BW, feed efficiency, or on the weight, protein, lipid, or fatty acid concentrations of the liver. Thiobarbituric acid reactive substances assay of liver and hemolysis assay of red blood cells (RBC) showed that the 150E diet decreased the susceptibility of liver and RBC to in vitro peroxidation at 13 and 22 d of age. In Experiment 2, 1-d-old poults were fed the 0E and 150E diets in a complete factorial arrangement with decreasing ratios of LO:LN (10, 5, and 1). Dietary LO:LN ratio had no effect on RBC hemolysis or cerebellum TOC concentration. As the ratio of LO:LN decreased, the arachidonic acid content of liver and cerebellum lipids decreased. Ratios of n-6 to n-3 fatty acids in liver and cerebellum were directly related to dietary LO:LN at 13 and 22 d of age.  相似文献   

15.
Nine M. bovis-infected cattle on a diet deficient in both protein and energy for 133 days lost approximately 17% of their original body weight. However, dietary restriction did not result in any significant reduction in skin sensitivity to PPD, in vitro production of IFN-gamma or lymphocyte blastogenesis. The number of circulating BoCD4+ cells and B cells were similar in both the malnourished and the control cattle. However, significantly lower numbers (P < 0.01) of circulating BoCD2+ cells, BoCD8+ cells, WC1+ gamma delta T cells and ACT2+ cells were found in the malnourished cattle. With the exception of inorganic phosphate, the changes in plasma biochemical parameters were unremarkable.  相似文献   

16.
A new classification has been proposed for prophylactic antiradiation drugs, which are divided into three groups: radioprotectors, stimulators of radioresistance and the means of protection from internal irradiation. Depending on organs (systems) for the protection of which they are designed, radioprotectors in their turn are subdivided into myelo-, entero- and cerebroprotectors; stimulators of radioresistance (depending on the optimal regimens of their use to develop a higher resistance of the organism) are subdivided into drugs that are effective in single and repeated (course) use; the means of protection from internal irradiation are subdivided into the drugs that prevent incorporation of radioiodine by the thyroid gland, and into the drugs preventing absorption of radionuclides in the digestive tract. The main features that distinguish radioprotectors from stimulators of radioresistance are presented. The former are characterized by such properties as exhibiting the effect exquisitely when prophylactically administered in doses close to those of maximal tolerance, greatest effect against shortterm (pulse) irradiation, rapid development and short duration of the radioprotective action period, reduction in the effect in repeated use, etc. Stimulators of radioresistance rank below radioprotectors in their effect against short-term irradiation, however, unlike the latter, they exhibit their protective effect against a long-term (low dose rate) exposure as well under the conditions of both prophylactic and therapeutic use; their radioprotective action is more prolonged, they are distinguished for their low toxicity and lower the risk of delayed sequelae of irradiation, etc. Examples of the most typical members of each group of prophylactic antiradiation drugs are cited, data are presented which characterize their radioprotective activity, the role and place in the system of antiradiation protection of troops and population.  相似文献   

17.
Target 17 of the Health Policy for Europe calls for the health-damaging consumption of dependence-producing substances such as alcohol, tobacco and psychoactive substances to be significantly reduced in all Member States between the year 1980 and the year 2000. With regard to alcohol, it is suggested that alcohol consumption be reduced by 25%, with particular attention to reducing harmful use. A question posed by a number of Member States is what is the level of per capita alcohol consumption of lowest risk to physical, psychological and social harm. A working group was convened to consider population levels of alcohol consumption with particular reference to the Member States of the European Region of WHO. A basis for understanding population problem experience can be established through the interaction between individual risk and distribution of consumption levels within the population. The working group concluded that public health policy within the European Region should continue to advise decreases of per capita consumption. Even when taking into account coronary heart disease, it can be concluded at the population level, across all ranges of alcohol consumption found in almost all countries of Europe, that a reduction in consumption is linked to better health. However, public health policy concerning alcohol should not be based solely on mortality. All outcomes of drinking, that is mortality, morbidity, social and criminal consequences, as well as quality of life, should be considered. The existing data relating alcohol consumption to health originates from countries primarily with a cultural experience of consuming alcohol. In those countries, where there is a cultural or religious tradition of not consuming alcohol, there can be no public health grounds for recommending alcohol consumption.  相似文献   

18.
Previous research has indicated that residential washing machines are potential sources of pollution due to the associated use of chemicals found in consumer products, for example, ethanol in laundry detergent and chlorine in bleach. Washing machines may also emit hazardous air pollutants found in contaminated drinking water. To better understand the extent and impact of chemical emissions from tap water, 26 experiments were completed using a residential washing machine and a cocktail of chemical tracers representing a wide range of physicochemical properties. Variable operating conditions for these experiments included water temperature, amount of clothes present in the machine, water volume, and level of washwater agitation. Chemical stripping efficiencies and mass transfer coefficients were determined during each cycle (fill, wash, and rinse) of a normal washing machine event. Headspace ventilation rates were determined using an isobutylene tracer gas. Mass transfer rates were significantly influenced by operating parameters as exhibited by a wide range of chemical stripping efficiencies. Stripping efficiencies ranged from 0.74 to 36% for acetone, 8.2 to 99% for toluene, 10 to 99% for ethylbenzene, and 6.9 to 100% for cyclohexane.  相似文献   

19.
Our objectives were to determine effects of head-out immersion (HOI), scuba breathing, and water temperature on cardiorespiratory responses to maximal aerobic work. Measurements of VO2, VE, and heart rate (HR) were obtained on seven men (27 yr, 177 cm, 67 kg) as they performed the same upright bicycling exercise to exhaustion (4-5 min) in 23 degrees C air and 30 degrees C water. Maximal oxygen uptake (VO2 max) during HOI was 3.18 liters - min-1, which was not statistically different from the mean of 3.29 liters- min-1 in air. When compressed air was breathed via scuba during HOI, VO2 max was 3.12 liters- min-1 and not significantly different from that when room air was breathed and a low-resistance valve in water was used. HOI decreased VE by 15.7 liters - min-1 and HR by 10 beats (b) - min-1. Scuba breathing further reduced VE by 22.0 liters - min-1. Similar measurements were made on four of the subjects after 18 min of HOI in water temperatures of 35,30, and 25 degrees C. Water temperature had no significant affect on VO2 max, although HR was 8 b- min-1 lower in 30 degrees C and 15 b - min-1 lower in 25 degrees C as compared to 35 degrees C water. The results show that VO2 max was not significantly changed by HOI, scuba breathing, or brief exposures to 25, 30, and 35 degrees C water, despite significant reductions that occurred for VE and HR.  相似文献   

20.
We used 216 Holstein steers (151 kg) in a 262-d trial to evaluate the influence of dietary magnesium level (.19, .25, and .32%) and laidlomycin propionate (LP; 0 vs 11 ppm, air-dry basis) on growth performance and NE value of the diet. During the initial 112 d of the trial, LP increased (P < .01) ADG (6.3%) and feed efficiency (4.2%). From d 112 until slaughter, LP increased (P < .05) ADG (9.7%) and feed efficiency (4.5%). Across the 262-d feeding period, LP supplementation enhanced (P < .01) ADG (8.9%) and feed efficiency (6.3%). There was an interaction (P < .05) between dietary Mg and LP on NE value of the diet. The enhancement in NE value of the diets owing to LP with .19, .25, and .32% dietary Mg were .5, 3.0, and 5.9%, respectively. Six Holstein steers (302 kg) were used in a 6 x 6 Latin square experiment to evaluate treatment effects on characteristics of ruminal and total tract digestion. There were no treatment interactions (P > .10) on site and extent of digestion of OM, starch, and N. Supplemental Mg increased (quadratic effect, P < .10) ruminal OM digestion. Neither LP nor dietary Mg level affected (P > .10) ruminal digestion of starch and feed N. Supplemental LP decreased (15%, P < .05) ruminal microbial efficiency. Total tract digestion of OM and N increased (linear effect, P < .01) with increasing dietary Mg level. There were interactions between LP and dietary Mg level on ruminal soluble-Mg concentration (linear effect, P < .01) and Mg absorption (quadratic effect, P < .05). Apparent total tract Mg digestion increased owing to LP (P < .01) and dietary Mg level (linear effect, P < .01). There were no treatment effects (P > .10) on ruminal pH. Dietary Mg level did not influence (P > .10) ruminal VFA concentrations or molar proportions. Supplemental LP increased (14%; P < .10) total ruminal VFA concentration but did not affect (P > .10) VFA molar proportions. We conclude that LP will increase daily weight gain and feed efficiency of calf-fed Holstein steers and that this response may be enhanced by increasing dietary Mg level.  相似文献   

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