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PubMed2004

[Patterns of service use for mental health disorders in Belgium. Results of the European Study on Epidemiology of Mental Disorders (ESEMeD)].

OBJECTIVE: To describe patterns of service use for emotional reasons or mental health in adult, non-institutionalised Belgians. METHOD: A representative random sample of non-institutionalised inhabitants from Belgium aged 18 or older (N = 2419) were interviewed between April 2001 and June 2002. The interview was performed by lay interviewers using the most recent version of the Composite International Diagnostic Interview (CIDI-2000). Apart from assessing mental disorders, the participants were asked to report their formal health services utilization due to their emotions or mental health in the past 12 months. RESULTS: About 11% reported the presence of a mental disorder in the past 12 months, of which one in three consulted a formal health service. Persons with a mood disorder were most likely to seek help (43%), followed by those with anxiety (38%) or an alcohol disorder (17%). General practitioners were consulted most often, sometimes combined with a psychiatrist. Among those who sought help, the majority received pharmacological treatment (sometimes combined with psychological treatment), and up to 25% did not receive any treatment. CONCLUSION: The utilization of formal health services for emotional raisons or mental health is very limited in Belgium. Moreover, a considerable proportion of those who sought help, did not get an appropriate treatment.

Adolescent↗
PubMed1994

Lay perspectives on oral hygiene performance: their use in hypothesis development.

This paper examines issues related to oral hygiene performance. Results from interviews with 113 adults who had received oral hygiene instruction in eight general dental practices are presented with an emphasis on three issues--the respondents' tooth cleaning pattern (the location within other routines of tooth cleaning), the respondents' tooth cleaning structure (the range of items used in tooth cleaning) and the reported content of the oral hygiene instruction given. Respondents reported that the oral hygiene instruction concentrated upon issues of tooth cleaning structure and did not consider issues of tooth cleaning pattern. The two variables (structure and pattern) were cross-tabulated to create an hypothesis to explain individual variation in tooth cleaning performance. The implications of this hypothesis for understanding patient compliance and developing further quantitative investigations are described.

Adolescent↗
PubMed1985

Evaluation of lay skills in cardiopulmonary resuscitation.

The theoretical knowledge and practical performance of 166 lay people attending a short cardiopulmonary resuscitation course were evaluated according to the American Heart Association standards. Before tt course no participant was able to perform even a bad attempt at cardiopulmonary resuscitation. Theoretical knowledge was good at the end of the course and at the refresher course six months later. At the end of the initial course 65% (57/88) of the participants examined could adequately compress and ventilate the manikin. After six months 44% (30/68) could perform resuscitation adequately. Women were as proficient as men, and elderly people in general were as proficient as the younger ones. The skill of carotid artery palpation was surprisingly well retained after six months. Data on pulmonary ventilation and cardiac massage were recorded simultaneously on a recording resuscitation manikin. When these objective data were compared with the American Heart Association standards only a few participants were able to perform correct cardiopulmonary resuscitation. The number of compressions and ventilations per minute were often insufficient. A large discrepancy between self, subjective, and objective assessment of cardiopulmonary resuscitation knowledge and performance was found. The importance of a rapid diagnosis, an immediate call for help, an adequate rate of cardiac massage, and a reduction in the time needed for ventilation should be emphasised at these courses. Refresher courses should be provided at least twice a year.

Adolescent↗
PubMed2004

Estimation of genetic parameters based on individual and group mean records in laying hens.

(1) The study was conducted to estimate the heritability, genetic correlations and breeding values of laying hens based on individual records and group mean records. (2) Records of two pure lines from a commercial breeding programme of White Leghorns from three generations housed in single cages and in group cages were used. A total of 8483 and 8817 individual records of lines A and D, respectively, and a total of 1358 (line A) and 1161 (line D) group mean records were analysed. (3) An animal model using Restricted Maximum Likelihood (REML) was used to estimate variance components of individual records. Group mean records were analysed using the sire model, taking heterogeneity of error variance and correlated residual effects into account. Breeding values of sires were estimated based on the BLUP method using a multivariate sire model. Spearman Rank correlations were used to compare sire breeding values estimated from individual records and from group mean records. The traits studied were monthly egg production, cumulative production and egg weight. (4) Heritability estimates based on individual records were higher than from group mean records. Heritabilities for cumulative production records were higher than for monthly production, based on individual as well as group mean records. The estimates of genetic correlations between monthly egg production and cumulative production were moderate to high. Egg production and egg weight recorded individually were highly genetically correlated with those recorded on group means. Sire breeding values estimated from individual records showed high correlations with those from group mean records. (5) Differences in the ranking of sire breeding values estimated from individual vs group mean records were negligible, indicating that no genotype x environment interaction exists. Selection based on individual performance records of laying hens housed in single cages could give a good response on performance of laying hens housed in group cages. Cumulative egg production over periods 1 to 6 is the best trait for the selection programme.

Animals↗
PubMed2005

Effects of qualitative feed restriction during rearing on the performance of broiler breeders during rearing and lay.

To prevent health and fertility problems associated with excessive weight gain, broiler breeders are severely feed restricted during rearing, which may affect welfare. We compared the effects of an experimental ad libitum feeding regimen based on qualitative restriction of food intake with conventional quantitative food restriction on the performance of female broiler breeders during rearing and lay. During rearing up to 20 wk of age, control birds were fed restricted amounts of standard broiler breeder mash once daily. Experimental birds had ad libitum access to the same standard mash mixed with 400 g of oat hulls/kg of feed and increasing concentrations of Ca propionate, an appetite suppressant. Mean total mash intake during rearing was 8.12 kg and did not differ between treatments. Both control and experimental birds showed an almost linear growth curve, treatment mean body weights were always within 100 g of the target weight line, and treatments did not differ for body weight uniformity. Groups were subjected to the same quantitative feed restriction from during lay. Feeding regimen during rearing did not affect number of eggs produced, egg weight, or egg quality up to 46 wk of age. We concluded that it may not be necessary to subject chicks to severe quantitative feed restriction to achieve desirable growth curves and body weight uniformity during rearing. Qualitative restriction of feed intake can achieve desirable growth curves in ad libitum fed chicks during rearing, and such a feeding regimen does not have negative effects on hen performance during lay.

Aging↗
PubMed1993

Research note: effect of tu-chung leaf (Eucommia ulmoides) on egg production performance, egg quality, and fat metabolism in laying hens at a late production stage.

The effects of tu-chung leaf (Eucommia ulmoides) supplementation on egg production performance, egg quality, and fat metabolism were investigated in laying hens at a late production stage. White Leghorn laying hens at 20 mo of age were provided ad libitum access to a practical diet with or without tu-chung leaf supplement for 3 mo. During the experimental period, egg production rate, egg weight, and feed intake were recorded every day. Egg samples from the last 3 days were collected to measure Haugh units and cholesterol concentration in the egg yolk. Plasma cholesterol concentration and abdominal fat weight were also determined. The results showed that no significant improvement in egg production was observed with tu-chung leaf addition. No significant effect of tu-chung was observed on Haugh units, plasma cholesterol, or egg yolk cholesterol, whereas abdominal fat weight was greater in hens fed the tu-chung diet than in those given the unsupplemented control diet. It was concluded that the beneficial effects of tu-chung leaf supplementation on egg production performance and egg quality were ambiguous and of little practical significance.

Animals↗
PubMed2005

Study on the transmission of deoxynivalenol and de-epoxy-deoxynivalenol into eggs of laying hens using a high-performance liquid chromatography-ultraviolet method with clean-up by immunoaffinity columns.

The transmission of deoxynivalenol (DON) and of its metabolite de-epoxy-DON into eggs has not been sufficiently elucidated until now. This question was addressed within the scope of a 16-week experiment with laying hens which were fed a maize-based diet with a DON concentration of 11.9 mg x kg(-1 )dry matter. Eggs were collected during weeks 2, 4, 8, and 16 of the experiment, and DON and its metabolite de-epoxy-DON were analyzed in freeze-dried yolk and albumen. In order to cover possible conjugates, all samples were incubated with beta-glucuronidase prior to extraction. Yolk and albumen were extracted with acetonitrile-water, and the extracts were purified with immunoaffinity columns (IACs) after a precleaning step. The toxins were determined by high-performance liquid chromatography (HPLC) with UV detection. The detection limits of both toxins were 5 and 8 microg x kg(-1) in freeze-dried yolk and albumen, respectively, corresponding to approximately 2.5 and 1 microg x kg(-1) in fresh samples. The recovery of DON and de-epoxy-DON in yolk was 80% and 78%, respectively, and in albumen 77 and 72%. Neither DON nor de-epoxy-DON or glucuronide conjugates of both substances could be detected in any of the samples. These results indicate that eggs do not contribute significantly to the dietary DON intake of humans.

Animals↗
PubMed2005

Modeling instructor preferences for CPR and AED competence estimation.

INTRODUCTION: Cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) skills competency can be tested using a checklist of component skills, individually graded "pass" or "fail." Scores are typically calculated as the percentage of skills passed, but may differ from an instructor's overall subjective assessment of simulated CPR or AED adequacy. OBJECTIVE: To identify and evaluate composite measures (methods for scoring checklists) that reflect instructors' subjective assessments of CPR or AED skills performance best. METHODS: Associations between instructor assessment and lay-volunteer skill performance were made using 6380 CPR and 3313 AED skill retention tests collected in the Public Access Defibrillation Trial. Checklists included CPR skills (e.g., calling 911, administering compressions) and AED skills (e.g., positioning electrodes, shocking within 90 s of AED arrival). The instructor's subjective overall assessment (adequate/inadequate) of CPR performance (perfusion) or AED competence (effective shock) was compared to composite measures. We evaluated the traditional composite measure (assigning equal weights to individual skills) and several nontraditional composite measures (assigning variable weights). Skills performed out of sequence were further weighted from 0% (no credit) to 100% (full credit). RESULTS: Composite measures providing full credit for skills performed out of sequence and down-weighting process skills (e.g., calling 911, clearing oneself from the AED) had the strongest association with the instructor's subjective assessment; the traditional CPR composite measure had the weakest association. CONCLUSION: Our findings suggest that instructors in public CPR and AED classes may tend to down-weight process skills and to excuse step sequencing errors when evaluating CPR and AED skills subjectively for overall proficiency. Testing methods that relate classroom performance to actual performance in the field and to clinical outcomes require further research.

Cardiopulmonary Resuscitation↗
PubMed1999

Comparing expert systems for identifying chest x-ray reports that support pneumonia.

We compare the performance of four computerized methods in identifying chest x-ray reports that support acute bacterial pneumonia. Two of the computerized techniques are constructed from expert knowledge, and two learn rules and structure from data. The two machine learning systems perform as well as the expert constructed systems. All of the computerized techniques perform better than a baseline keyword search and a lay person, and perform as well as a physician. We conclude that machine learning can be used to identify chest x-ray reports that support pneumonia.

Algorithms↗
PubMed1976

[Substitution of protein animal feed through lysine-supplemented high-protein wheat during the breeding and laying periods of hens. 5. Influence of graded lysine supplements fed during the laying period on the production characteristics of hens].

A large-scale trial was performed with 1500 laying hens which were kept under conditions of industrial egg production. The trial was carried out to investigate whether supplements of L-lysine would increase the food value of high-protein wheat and in which way a proportional decrease of dietary protein by 50% would affect the egg production of the hens. Additionally, studies were made to investigate whether the egg production of the hens was influenced by changes in the plane of feeding of the young hens during their rearing period. Both the young hens and the laying hens received isonitrogenous and isocaloric rations containing 4 graded levels of lysine. All of the 16 groups of the hens received a different diet. This was achieved by suitable combinations within the feeding regime. The control animals received, at all periods of age, food prepared on the basis of government-controlled standard rations. No significant differences in the level of food consumption were observed between the experimental groups whereas the control birds consumed more food (124 g per bird/day) than the experimental hens (120 g per bird/day; alpha less than 0.05). The levels of production were in all groups associated with the lysine content of the ration. The lysine-deficient birds produced the smallest eggs, layed the smallest number of eggs and consumed the largest quantity of food per 100 g of egg weight. The egg production of the hens in groups 11 and 12 (receiving a fish meal ration during the rearing period and a fish meal or wheat ration + 0.15% L-lysine during the laying period) was 70% of that of the birds in the control groups. The results of the present trial suggest that lysine-supplemented high-protein wheat rations for laying hens could be used but care should be taken that the plane of feeding for the young hens will not be too much restricted.

Animal Feed↗
PubMed2006

Habitat difference in abundance of willow leaf beetle Phratora vulgatissima (Coleoptera: Chrysomelidae): plant quality or natural enemies?

Herbivorous insects are influenced by both 'bottom-up' forces mediated through host plants and 'top-down' forces from natural enemies. Few studies have tried to evaluate the relative importance of the two forces in determining the abundance of insects. The leaf beetle Phratora vulgatissima Linnaeus sometimes occurs at high densities and severely damages the willow Salix cinerea in forest habitats. For willows growing in open agricultural landscapes (farmland S. cinerea), the leaf beetle generally occurs at low densities and plants receive little damage. The purpose of the present study was to evaluate the relative importance of host plant quality and natural enemies behind the observed difference in P. vulgatissima abundance. Female egg-laying and larval performance (growth and survival) were studied on caged willow branches in the field to investigate if plant quality differs between S. cinerea trees growing in forest and farmland habitats. The survival of eggs exposed to natural enemies was examined to see if predation could explain the low abundance of leaf beetles on farmland willows. The results indicated no difference in plant quality; female egg laying and larval performance did not differ between the forest and the farmland. However, heteropteran predators (true bugs) were more abundant, and the survival of eggs was lower, on plants in the farmland habitat than in the forest habitat. The data suggest that the low abundance of P. vulgatissima on farmland willows could not be explained by a poor quality of plants, but more likely by high predation from heteropterans.

Animals↗
PubMed1995

Effect of feeding raw and treated common vetch seed (Vicia sativa) on the performance and egg quality parameters of laying hens.

Two experiments were conducted to study the effect of feeding raw or treated common vetch seeds (V) on BW, feed intake (FI), egg production (EP), feed conversion (FC), egg weight (EW), shell thickness (ST), yolk color score (YC), and Haugh unit score (HU) of Single Comb White Leghorn hens for 56 d. In Experiment 1, diets contained 0, 7.5, 15, and 22.5% raw V. Compared with the control, the 22.5% V diet decreased (P < .05) BW, FI, and EP. In Experiment 2, intact or ground (G) V were either soaked (S) in water (1:5) for 24 h or autoclaved (A) at 103.5 x 10(3) Pa for 8 h, and then dried (D) at 55 C for 24 h. Eight diets were used, a corn soybean (control) and seven others, each containing 25% V, previously subjected to the forementioned treatments as follows: untreated V (UV), SDV, GSDV, ADV, GADV, SADV, and GSADV. Compared with the control, the UV diet decreased (P < .05) FI (75 vs 98 g) and EP (47.3 vs 88.7%), increased FC (1.99 vs 1.4 kg feed per dozen eggs), and induced BW loss (-63 vs 49 g). Soaking intact V improved (P < .05) FI (85 g) and EP (69%). Remaining treatments resulted in further improvement. Hens fed all V diets produced eggs with HU score 13 points better than that of the control (P < .05). In both experiments, EW, YC, and ST were not different among treatments. Results indicated that autoclaved V at 25% level was not detrimental to layers' performance.

Animal Feed↗
PubMed1990

Some observations on the influence of vitamin D metabolites when added to the diet of commercial laying hens.

Three experiments were conducted to study the influence of two vitamin D3 metabolites on the performance of commercial laying hens. In Experiment 1, adding of .75, 1.50, 3.00, and 4.50 micrograms of 1 alpha-hydroxycholecalciferol (1 alpha-OHD3) or of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] per kg to the diet containing 2,200 ICU of vitamin D3 from 55 micrograms of cholecalciferol per kg of diet resulted in increased plasma calcium (Ca) and phosphorus (P). The response was greater from the 1,25-(OH)2D3 metabolite than from the 1 alpha-OHD3 metabolite. Neither metabolite affected tibia breaking strength (TBS), egg production (EP), egg weight (EW), feed consumption (FC), feed conversion, eggshell quality (ESQ), fertility, or the hatchability of eggs or the tibia ash (TA) of the day-old chick. In Experiment 2, the EP, EW, FC, ESQ and TA of the hens were not affected when 1.5 micrograms of 1,25-(OH)2D3 were added to each kilogram of a corn-soybean meal diet containing either .38 or .43% P with adequate vitamin D3. Adding the 1,25(OH)2D3 metabolite to the low-P diet reduced plasma Ca and increased TBS. However, adding 1,25-(OH)2D3 to the high-P diet increased plasma Ca and P. In Experiment 3, the EP, ESQ, FC, and TA of the hens were significantly lower when the diet contained 2.04% Ca rather than 3.04% Ca. Plasma Ca and P, EW, or TBS were not affected by the dietary Ca. Neither the plasma Ca and P, EP, EW, ESQ nor the TBS and TA were influenced by adding the 1,25-(OH)2D3 metabolite to either diet.

Animal Feed↗
PubMed1984

A comparison of the effect of two force molting methods on performance of two commercial strains of laying hens.

A low-sodium diet (.08% Na) was used to force molt 409 hens. Another 421 hens were force molted by conventional water and feed restrictions. Birds were 68 weeks of age at that time, and two strains were about equally represented in each treatment group. These strains were: A, DeKalb; and B, Hisex. The low-sodium diet and water were provided ad libitum to the first group for the entire period of molt (42 days). The second group received no water for 3 days, and no feed for 4 days, after which incremental amounts of whole oats were provided as the only feed until Day 18. After Day 18, incremental amounts of a regular laying mash and decremental amounts of whole oats were provided through Day 26, when laying mash only was given ad libitum. Both treatment groups were in the same building and received the same lighting program during the force-molt period. This program consisted of: Days 1 to 3, no light; Days 4 to 18, 8 hr/day; Days 19 to 25, 9 hr/day; Day 26, 10 hr; then, light was increased 30 min weekly until 14 hr daily was attained. The low-sodium group ceased laying after 28 to 31 days, lost 8.7% of their premolt body weight, reduced feed consumption by 35%, and decreased egg production from 62.3% (in the 28 days preceding the molt) to 19% in the 42 days of molt; their mortality rate was 3.4%.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed2005

Effects of an experimental phytase on performance, egg quality, tibia ash content and phosphorus bioavailability in laying hens fed on maize- or barley-based diets.

A 24-week performance trial was conducted to evaluate the efficacy of an experimental phytase on performance, egg quality, tibia ash content and phosphorus excretion in laying hens fed on either a maize- or a barley-based diet. At the end of the trial, an ileal absorption assay was conducted in order to determine the influence of phytase supplementation on the apparent absorption of calcium and total phosphorus (P). Each experimental diet was formulated either as a positive control containing 3.2 g/kg non-phytate phosphorus (NPP), with the addition of dicalcium phosphate (DCP), or as a low P one, without DCP addition. Both low P diets (containing 1.3 or 1.1 g/kg NPP) were supplemented with microbial phytase at 0, 150, 300 and 450 U/kg. The birds were housed in cages, allocating two hens per cage as the experimental unit. Each of 10 dietary treatments was assigned to 16 replicates. Low dietary NPP (below 1.3 g/kg) was not able to support optimum performance of hens during the laying cycle (from 22 to 46 weeks of age), either in maize or barley diets. Rate of lay, daily egg mass output, feed consumption, tibia ash percentage and weight gain were reduced in hens fed low NPP diets. The adverse effects of a low P diet were more severe in hens on a maize diet than in those on a barley diet. Low dietary NPP reduced egg production, weight gain, feed consumption and tibia ash content and microbial phytase supplementation improved these parameters. Hens given low NPP diets supplemented with phytase performed as well as the hens on positive control diets containing 3.2 g/kg of NPP. A 49% reduction of excreta P content was achieved by feeding hens on low NPP diets supplemented with phytase, without compromising performance. Phytase addition to low NPP diets increased total phosphorus absorption at the ileal level, from 0.25 to 0.51 in the maize diet and from 0.34 to 0.58 in the barley diet. Phosphorus absorption increased linearly with increasing levels of dietary phytase. Mean phosphorus absorption was higher in barley diets than in maize diets (0.49 vs 0.39).

6-Phytase↗
PubMed2001

Effects of dietary chromium picolinate supplementation on performance and plasma concentrations of insulin and corticosterone in laying hens under low ambient temperature.

This experiment was conducted to evaluate the effects of chromium (chromium picolinate) on performance and plasma concentrations of insulin and corticosterone of laying hens (Ross Brown) under a low ambient temperature (6.9 degrees C). One hundred and twenty laying hens (46 weeks old) were divided into four groups, 30 hens per group. The laying hens were fed either a control diet containing 710.3 p.p.b. chromium or the control diet supplemented with 100, 200 or 400 microg chromium/kg diet. Increasing supplemental chromium increased live weight change (p < or = 0.001, linear) and egg production (p < or = 0.001, linear) and also improved feed efficiency linearly (p < or = 0.001). Live weight change and egg production also had quadratic responses (p < or = 0.001) to increasing chromium supplementation. Plasma insulin concentration increased linearly (p < or = 0.001), whereas corticosterone concentration decreased linearly (p < or = 0.001) as dietary chromium supplementation increased. The results of this study indicate that supplemental dietary chromium, 200 p.p.b. in particular, had a positive effect on performance and increased the plasma insulin concentration of laying hens under cold stress.

Animals↗
PubMed2002

Effects of F-strain Mycoplasma gallisepticum inoculation at twelve weeks of age on performance and egg characteristics of commercial egg-laying hens.

The effects of F-strain Mycoplasma gallisepticum (FMG) inoculation during the pullet period on the subsequent performance and egg characteristics of commercial Single Combed White Leghorn hens were evaluated. In two trials, BW, feed consumption, egg production (EP), egg weight, egg size class, relative eggshell water vapor conductance, and relative percentages of eggshell, yolk and albumen weights were determined through approximately 60 wk of age. In each trial, pullets at 12 wk of age were randomly assigned to negative pressure biological isolation units. Birds in one-half of the total units were inoculated with FMG, and the other half were sham-inoculated with sterile media. In both trials, onset of lay was delayed approximately 1 wk in layers inoculated with FMG. Control birds that had not been previously inoculated with FMG laid their first egg at 18 wk of age, while birds that had been previously inoculated with FMG laid their first egg at 19 wk of age. In Trial 1, FMG-inoculated hens laid significantly fewer total eggs, which became apparent at each week after Week 42. In Trial 2, a numerical decrease in total EP occurred, and the percentage of undersized eggs laid by FMG-inoculated birds was significantly lower at 19 wk of age but was higher at 20 and 21 wk when compared to controls. Mortality was not significantly different between the treatments in either trial. These data demonstrate that when birds are housed in isolation facilities and inoculated with FMG at 12 wk of age, onset of lay is delayed. These data also suggest that FMG may lead to delays in undersize EP and decreases in total EP. However, because significant FMG effects on these parameters were observed in only one trial, additional studies may be necessary to verify these effects.

Aging↗