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At least 217 records · Page 12Linked to original sources
PubMed2006

Quality of lay person CPR performance with compression: ventilation ratios 15:2, 30:2 or continuous chest compressions without ventilations on manikins.

The new CPR guidelines emphasise chest compression depth and have increased the compression:ventilation ratio to cause less time intervals without chest compressions. How this change may influence the quality of chest compressions is not documented. Sixty-eight volunteers among travellers at Oslo international airport and a senior citizen centre performed 5 min of CPR on a manikin with compression:ventilation ratios 15:2, 30:2 or continuous chest compressions. Median age was 37.5 years (range 15-87), 59% were men, and 71% reported CPR training median 8 years (3-15) previously. Three of 22, 4 of 23 and 3 of 23 subjects in the 15:2, 30:2 and continuous compressions groups respectively stopped before 5 min had passed. Mean compression depth was 41 +/- 11, 45 +/- 8 and 30 +/- 8 mm, respectively. Depth was reduced as a function of time in the continuous compression group. Number of compressions per minute was 40 +/- 9, 43 +/- 14 and 73 +/- 24 and percent no flow time 49 +/- 13%, 38 +/- 20% and 1 +/- 2%, respectively. In conclusion, continuous chest compressions without ventilations gave significantly more chest compressions per minute, but with decreased compression quality. No flow time for 30:2 was significantly less than for 15:2.

Adolescent↗
PubMed1988

Influence of dietary energy, nutrient density and environmental temperature on pullet performance in early lay.

1. Alterations in dietary metabolisable energy (ME) concentration had a limited influence on food and nutrient intakes and egg mass output of hens in early lay kept at the prevailing air (10 degrees to 24 degrees C), cold (6 degrees to 16 degrees C) or hot (25 degrees to 35 degrees C) temperatures. 2. Energy intakes were not improved by increasing the dietary concentrations of nutrients other than energy. 3. At prevailing air and cold temperatures all dietary ME-nutrient density combinations allowed hens to meet the recommended daily protein intake but only hens fed the most concentrated diets were able to meet this recommendation at hot temperatures. 4. Even the highest intakes of ME and protein achieved at hot temperatures failed to increase egg mass output to the values attained on any diet at cold temperatures.

Animals↗
PubMed1988

Influence of 1,25-dihydroxyvitamin D3 on the performance of commercial laying hens.

An experiment was conducted to determine the influence of adding 4 micrograms/kg of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] to the diet of 68-wk-old commercial egg production-type hens. The addition of the 1,25(OH)2D3 to the diet for 21 days resulted in significantly decreased egg production, egg weight, and feed consumption, and significantly increased plasma P, and bone-breaking load. Specific gravity of eggs, plasma Ca, tibia ash, and fertility and hatchability of eggs were not significantly affected by the addition of 1,25(OH)2D3 to the diet.

Animals↗
PubMed1990

[The vitamin A supply of laying hens including during rearing. 2. Effect of varied vitamin A supplementation of mixed feed in rearing on production in the laying period].

In six experiments with laying hybrids the influence of a varied nutritive beta-carotene and vitamin A supply during rearing on the performance in the laying period was tested. Basal rations poor in carotene without vitamin A supplementation in the rearing period diminished feed intake and laying performance in the laying period, retarded the beginning of intensive laying and increased feed expenditure per 100 g egg if the feed for laying hens contained less than 5000 IU vitamin A per kg. Relations between varied vitamin A supply and the performance parameters of the laying performance could not be proved if chick and young hen feed with maize even without vitamin A supplement or if rearing feed with approximately 2500 IU vitamin A or laying hen feed greater than 5000 IU vitamin A supply were used.

Analysis of Variance↗
PubMed1991

Influence of orotic acid on performance, liver lipid content, and egg cholesterol level of laying hens.

Three experiments were conducted to determine the effects of dietary orotic acid (OA) on laying hen performance, liver lipid content, and plasma and egg cholesterol levels. Laying hens were fed a basal diet supplemented with 0, .5, 1.0, and 2.0% OA for 8 wk. Performance of the hens and cholesterol levels were measured at biweekly intervals. In all three experiments, OA decreased (P less than .05) BW in a linear manner. In two experiments, OA caused a linear decrease in total liver lipid (P less than .05), and in a third experiment OA resulted in a quadratic effect (P less than .01) on liver lipid content. There were no effects observed by OA supplementation on egg weight, yolk weight, percentage yolk, or egg production. Orotic acid failed to influence egg cholesterol content in any of the biweekly measurements of the three experiments. In two experiments, total plasma cholesterol content was not influenced by OA supplementation. Orotic acid significantly reduced (P less than .05) free and total plasma cholesterol in a third experiment when measured at Weeks 4, 6, and 8 of the experiment. The data indicate that OA is an ineffective dietary supplement for reducing egg cholesterol levels in laying hens.

Animals↗
PubMed2003

Influences of supplemental dietary poultry fat and F-strain Mycoplasma gallisepticum infection on the early performance of commercial egg laying hens.

F-strain Mycoplasma gallisepticum (FMG) may alter reproductive performance in layers through its effects on lipid metabolism. Therefore, the influences of 1.5% supplemental dietary poultry fat (PF) and FMG infection on the early performance of commercial egg-laying hens were determined. Birds were either sham- or FMG-inoculated at 12 wk, and experimental diets were initiated at 20 wk of age. Body weight at 12, 20, and 24 wk, total daily egg mass, feed consumption and feed conversion at 20 and 24 wk, weekly egg weight between 19 and 26 wk, weekly egg production (EP) between 18 and 26 wk, and weekly mortality between 12 and 26 wk of age were determined. Inoculation with FMG reduced EP at 18 and 19 wk of age. Between 20 and 26 wk, FMG reduced EP in birds fed control diets, conversely, PF eliminated differences in EP between sham- and FMG-inoculated birds. Furthermore, at wk 20 and 24, birds consumed less feed when fed PF-supplemented diets than when fed control diets if they were sham-inoculated, but the difference in feed consumption between diets was ameliorated if birds were previously inoculated with FMG. These data demonstrate that the effects of a 12-wk inoculation of FMG on EP and feed consumption through 26 wk of age in commercial egg-laying chickens can be modified by 1.5% supplemental dietary P F. More specifically, PF may alleviate reductions in early EP due to FMG.

Aging↗
PubMed1982

Effect of dietary vicine and vitamin E supplementation on the productive performance of growing and laying chickens.

1. Experiments were conducted to study the effects of dietary vicine (2, 6-diamino-4, 5 dihydroxy pyrimidine-5 (beta-D-glucopyranoside)) and supplemental vitamin E on the performance of laying hens and growing chicks, haemolysis of erythrocytes than birds fed on a control diet. 3. Vicine when fed to laying hens had a very dramatic effect. It depressed food consumption, egg weight, fertility and hatchability of eggs. Packed cell volume and erythrocyte haemoglobin levels and led to increased liver weights, liver glutathione levels, liver and plasma lipid levels, plasma lipid peroxide levels and erythrocyte haemolysis in vitro. Liver protein and plasma vitamin E:lipid levels were not altered. Vitamin E supplementation slightly increased egg weights, markedly improved fertility and hatchability of eggs and lowered liver weights and lipid levels but did not affect the other factors examined. 4. It is concluded that vicine which was isolated from faba beans (Vicia faba L.) has a marked influence on the metabolism of the laying hen and only a slight effect on growing chick. Vicine or its metabolites or both cause peroxidation of cellular components which result in abnormal lipid transport of synthesis or both, increased fragility of erythrocytes, and reduced fertility. These effects are overcome to varying extents by supplemental vitamin E.

Animals↗
PubMed1976

[The substitution of lysine supplemented high protein wheat for protein feeds during the rearing and laying periods of hens. 8. Nitrogen excretion and true amino acid digestibility as an effect of various lysine levels and successive laying periods].

Digestibility trials were performed with laying hens receiving 3 types of rations containing equal proportions of the same dietary components. The percentage of high-protein wheat in these rations was 74%. Ration I was supplemented with 0.12% lysine while 0.06% lysine was added to ration II; ration III remained unsupplemented. The crude protein content of rations 1 to 3 was 16.1%, 16.5% and 16.6%, respectively. The corresponding lysine percentages were 0.66, 0.62 and 0.56. Studies were made to investigate the influence of different lysine levels on the rate of N excretion and various amino acid data. These studies were carried out during two successive laying periods. Only random differences between the data for urinary N excretion and N balances per kg liveweight were obtained in the two laying periods and for the different lysine levels. The true lysine digestibility was significantly lower in the poor-lysine ration as compared with the ration with 0.66% lysine. Moreover, the absorptive capacity for thio-amino acids is influenced by the lysine level of the ration. The proportion of lysine contained in faecal crude protein increased with the decreasing lysine content of the ration. Similarly, the total number of amino acids present in faecal crude protein increased with the declining supply of lysine. These findings suggest that relatively more NPN compounds are excreted in the faeces if adequate amounts of amino acids are supplied rather than when one amino acid is deficient.

Amino Acids↗
PubMed1975

[Substitution of protein feed through lysine-supplemented high-protein wheat during the rearing and laying period of hens. 4. Effect of graded lysine doses during the rearing of young hens on the performance characteristics during the laying period].

1530 laying hybrid hens kept under conditions of large-scale production were used to test whether varying lysine levels given to young hens would later on influence the production of the birds during their laying period. Thus, young hens received isonitrogenous and isocaloric diets with varying lysine content (group 1-4: 0.59%, 0.61%, 0.54%, 0.46%) and varying sources of lysine (group 1: wheat/fish meal; group 2--4: wheat/synthetic L-lysine). The ration used for the controls was prepared on the basis of nationally prescribed formulas.

Animal Feed↗
PubMed1982

Effects of restricted feeding in the growing and laying periods on the performance of White Leghorn by Australorp crossbred and White Leghorn strain cross chickens.

1. The effects of restricted feeding in the rearing and laying periods on the performance of three White Leghorn cockerel by Australorp pullet crossbred strains and one White Leghorn strain cross were studied in two experiments. 2. After feeding ad libitum in the rearing period, mean body weights of the three crossbred strains at 20 weeks of age were 1.75, 1.66 and 1.55 kg and that of the White Leghorn strain cross was 1.40 kg. The differing restrictions during rearing reduced mean body weight at 20 weeks by 14 to 33% and increased the time to sexual maturity by 8 to 23 d. 3. All restriction regimes during rearing increased mean egg weight and tended to reduce mortality in the laying period. Optimum hen-day egg number over 64 weeks of lay was obtained following mild restriction (14% body weight reduction) of the two heavier strains or ad libitum feeding of the lighter strains. Over 48 or 64 weeks of lay, egg number per hen housed (at 18 to 20 weeks of age) was optimised after moderately restricting (14 to 21% body weight reduction) the crossbred strains or feeding the White Leghorn strain cross ad libitum. 4. Over 64 weeks of lay, mortality was reduced from 19.3% to 10.5% in the lightest crossbred strains, in which a high proportion of deaths were associated with Marek's disease and lymphoid leucosis, by restriction during rearing. 5. Restricting food intake by 7 or 8% throughout the laying period reduced hen-housed egg number and mean egg weight of all four strains. The reduction in hen-day egg number associated with food restriction during lay was less for the heavier strains that had also been restricted during rearing. 6. Metabolisable energy intakes required to support maximum production over 64 weeks of lay were 1.23 to 1.36 MJ/d.

Animals↗
PubMed2001

Variation in the ovarian and plasma progesterone and estradiol levels of the domestic hen during a pause in laying.

Little is known about the physiological events occurring in the chicken ovary during a pause in laying, therefore the aim of the present study was to examine changes in sex steroid concentration in the follicle wall and blood plasma during cessation of egg laying. The experiment was performed on laying Isa Brown hens. Control hens were fed ad libitum whereas the experimental ones were subjected to a pause in laying by complete food deprivation for 5 days and water deprivation on 3 day followed by feeding every second day up to 9 day and then ad libitum. Blood samples were taken from the wing vein each day. The hens were decapitated on day 3, 6, 9, and 16. The ovary was isolated and the following follicles were dissected: white (1-2; 2-4; 4-6; 6-8 mm) and yellow preovulatory ones (F1-F3). Progesterone and estradiol were measured in the follicle wall and blood plasma by RIA methods. The hens stopped egg laying on day 4 and began egg restoration on day 14 of the experiment. Cessation of egg laying was preceded by a decrease in estradiol and progesterone levels in the ovary as well as in the blood plasma. The plasma level of these steroids began to increase 7 days before the start of egg restoration. Autopsy of the ovary showed that the atrophy of the chicken yellow preovulatory follicles during the pause in laying was accompanied by a significant increase in the total number of white follicles.

Animals↗
PubMed2001

Use of modified OSCEs to verify technical skill performance and competency of lay caregivers.

BACKGROUND: The demands on lay caregivers of blood and marrow stem-cell transplant recipients are complex. Effective caregiver education that clearly delineates and demonstrates what needs to be learned is needed, as well as a method to evaluate caregiver's skill-based competencies. METHOD: A pilot study was conducted to determine the feasibility of adapting objective structured clinical examinations (OSCEs) for teaching and evaluation in lay caregiver educational programs. A modified OSCE, a performance-based assessment process, with seven practice stations for the care of tunneled central lines was developed and tested with 13 laypersons. Inter-rater techniques were used to establish accuracy and reproducibility of the examination. RESULTS: Reproducibility of station scenarios and accuracy in performance evaluation were supported by an overall kappa coefficient of 0.94, indicating excellent agreement. Participants' overall mean performance scores were 80% for knowledge and 94% for skills. CONCLUSION: The use of modified OSCEs for teaching and evaluating lay caregivers' competencies for complex care demands is feasible, accurate, and warrants further investigation.

Adult↗
PubMed2004

Teaching public access defibrillation to lay volunteers--a professional health care provider is not a more effective instructor than a trained lay person.

BACKGROUND: Survival improves in witnessed out-of-hospital cardiac arrest if the victim receives bystander-initiated cardiopulmonary resuscitation and rapid defibrillation (BLS/AED). The European Resuscitation Council has a simple programme to teach these life-saving skills that require no previous experience of automated external defibrillators (AEDs). To be able to implement the use of AEDs widely, many instructors are needed, and therefore, lay persons may also be used as trainers. The purpose of this randomized study was to compare lay volunteers trained by a lay person with those trained by a health care professional using the Objective Structured Clinical Examination (OSCE). METHODS: Eight instructors, including four lay persons and four health care professionals, were given a basic course and an instructor course in CPR-D by the same instructor. All newly trained instructors trained 38 lay volunteers (19 pairs) who had no previous training in the use of a defibrillator. The lay volunteers performed the OSCE 2-3 weeks after the course. The OSCE comprised two scenarios with a manikin: the first, a patient in cardiac arrest with ventricular fibrillation, and the second, an imminent cardiac arrest with asystole as the initial rhythm. The same OSCE was performed by a group of lay first aiders practicing every 2 weeks who served as the control group. RESULTS: No statistical difference was present between the two groups of lay volunteers in the OSCE. All were able to use the AED and follow instructions. They identified patients with ventricular fibrillation and cardiac arrest, but had difficulties identifying cases with imminent cardiac arrest. The control group of trained first aiders performed significantly more effectively than the newly trained lay persons. CONCLUSIONS: No significant benefit exists in the trainer being a health care professional, but thorough training and subsequent rehearsing of the skills learned are crucial.

Cardiopulmonary Resuscitation↗
PubMed1984

Relationship of dietary calcium level during the prelay phase of an induced molt to postmolt performance.

Leghorn laying hens were induced to molt by a combination of photoperiod reduction and fasting for 14 days, during which time the hens lost 31.5% of their initial body weight. The hens were then assigned to one of four diets containing 1.0, 1.75, 2.5, or 3.5% calcium until egg production resumed. The 3.5% calcium diet was fed to all treatments from the resumption of 5% egg production. Postmolt egg production and feed conversion were not affected significantly. Egg weight, shell weight, and egg specific gravity were not affected consistently. It was concluded that high dietary calcium levels immediately postfast have no adverse effect on postmolt performance.

Animals↗
PubMed2004

Effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on performance and metabolism of laying hens.

An experiment was conducted to evaluate the effects of feeding laying hens grains naturally contaminated with a combination of Fusarium mycotoxins. Parameters measured included performance, organ weights, and plasma chemistry. One hundred and forty-four, 45-wk-old laying hens were fed diets including: (1) control, (2) contaminated grains, and (3) contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA) for a 12-wk period. The feeding of contaminated grains decreased feed consumption compared with controls in the first 4 wk. Feed consumption increased, however, from 4 to 8 wk and from 8 to 12 wk. The efficiency of feed utilization (feed consumption/egg mass) decreased compared with controls in the periods from 4 to 8 and from 8 to 12 wk when birds were fed contaminated grains. Supplementation with GMA decreased feed consumption and increased the efficiency of feed utilization in the period from 8 to 12 wk. Egg production and egg mass decreased in wk 4 and 8 compared with controls when contaminated grains were fed, whereas egg and eggshell weights decreased in the fourth wk. Plasma uric acid concentrations increased throughout the experiment and relative kidney weights increased at the end of the experiment compared with controls when birds were fed contaminated grains. The feeding of GMA prevented the elevation in uric acid concentrations and relative kidney weights. It was concluded that layer performance and metabolism were adversely affected by chronic feeding of a combination of Fusarium mycotoxins, and that GMA prevented many of these effects.

Adsorption↗
PubMed1983

Performance of dwarf and normal laying hens as influenced by protein level and cage density.

The performance of dwarf and normal White Leghorn laying hens with similar genotypes other than for the dwarf gene (dw) was observed over thirteen 28-day periods in a factorial arrangement involving four protein levels (20.0, 18.1, 16.4 or 14.3% protein plus supplemental methionine) and two densities (two or three birds per standard 10 X 16 in cage). The normal birds had significantly higher overall hen-day egg production, egg weight, and body weight, but the dwarf birds excelled for feed efficiency and adult viability. Significant genotype X ration interactions were observed for egg lay, egg weight, body weight, and feed efficiency, primarily due to the relatively poor performance of the dwarf birds on the 14% protein. A significant genotype X density interaction resulted for feed efficiency, due to a higher efficiency in 3-bird than in 2-bird cages for dwarf birds, while the reverse was true for normal birds. These results suggest that the potential of the dwarf gene for increasing the efficiency of commercial egg layers can be enhanced by further study as to optimal nutrition and management regimens.

Animals↗