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National Institutes of Health Consensus Development Conference Statement: breast cancer screening for women ages 40-49, January 21-23, 1997. National Institutes of Health Consensus Developmental Panel.

OBJECTIVE: To provide heatlh care providers, patients, and the general public with a responsible assessment of currently available data regarding the effectiveness of mammography screening for women ages 40-49. PARTICIPANTS: A non-Federal, nonadvocate, 12-member panel representing the fields of oncology, radiology, obstetrics and gynecology, geriatrics, public health, and epidemiology and including patient representatives. In addition, 32 experts in oncology, surgical oncology, radiology, public health, and epidemiology, presented data to the panel and to a conference audience of 1,100. EVIDENCE: The literature was searched through Medline and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed its conclusions based on the scientific evidence presented in open forum and the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised draft statement at the end of the conference. The final statement with a minority report was completed within several weeks after the conference. CONCLUSIONS: The Panel concludes that the data currently available do not warrant a universal recommendation for mammography for all women in their forties. Each woman should decide for herself whether to undergo mammography. Her decision may be based not only on an objective analysis of the scientific evidence and consideration of her individual medical history, but also on how she perceives and weighs each potential risk and benefit, the values she places on each, and how she deals with uncertainty. However, it is not sufficient just to advise a woman to make her own decision about mammograms. Given both the importance and the complexity of the issues involved in assessing the evidence, a woman should have access to the best possible relevant information regarding both benefits and risks, presented in an understandable and usable form. Information should be developed for women in their forties regarding potential benefits and risks to be provided to enable each woman to make the most appropriate decision. In addition, educational material to accompany this information should be prepared that will lead women step by step through the process of using such information in the best possible way for reaching a decision. For women in their forties who choose to have mammography performed, the costs of the mammograms should be reimbursed by third-party payors or covered by health maintenance organizations so that financial impediments will not influence a woman's decision. Additionally, a woman's health care provider must be equipped with sufficient information to facilitate her decisionmaking process. Therefore, educational material for physicians should be developed to assist them in providing the guidance and support needed by the women in their care who are making difficult decisions regarding mammography. The two panel members writing a minority report believed the risks of mammography to be overemphasized by the majority and concluded that the data did support a recommendation for mammography screening for all women in this age group and that the survival benefit and diagnosis at an earlier stage outweigh the potential risks.

Adult↗

ICSH recommendations for the analysis of red cell, white cell and platelet size distribution curves. Methods for fitting a single reference distribution and assessing its goodness of fit. International Committee for Standardization in Haematology. ICSH Expert Panel on Cytometry.

The algorithm in Figure 7 summarizes the overall approach to fitting a single reference distribution. If no statistically significant difference is found, the investigation should assess whether the power of the chi-squared test was insufficient to detect differences of practical significance. If a statistical difference is found, Appendices B and C and Figure 6 may be used to determine whether the sample size and the power have led to the detection of an effect size too small to be of importance.

Algorithms↗

Phenylketonuria (PKU): screening and management.

OBJECTIVE: To provide health care providers, patients, and the general public with a responsible assessment of currently available data regarding screening for, and management of. phenylketonuria (PKU). PARTICIPANTS: A non-Federal, non-advocate, 14-member panel representing the fields of pediatrics, genetics, human development, public policy, nursing, molecular physiology, and including patient representatives. In addition, 19 experts in pediatrics, medical genetics, psychology, pediatric neurology, biochemical and molecular genetics, and gene therapy presented data to the panel and to a conference audience of more than 300. EVIDENCE: The literature was searched using MEDLINE and an extensive bibliography of references was provided to the panel. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. The draft statement was made available on the World Wide Web immediately following its release at the conference and was updated with the panel's final revisions. CONCLUSIONS: Genetic testing for PKU has been in place for almost 40 years and has been very successful in the prevention of severe mental retardation in thousands of children and adults. Metabolic control is necessary across the lifespan of individuals with PKU. A comprehensive, multidisciplinary, integrated system is required for the delivery of care to individuals with PKU. Greatly needed are consistency and coordination among screening, treatment, data collection, and patient support programs. There should be equal access to culturally sensitive, age-appropriate treatment programs. Ethically sound, specific policies for storage, ownership, and use in future studies of archived samples remaining from PKU testing should be established. Research into the pathophysiology of PKU and relationship to genetic, neural, and behavioral variation is strongly encouraged. Uniform policies need to be established to remove from the individual and the family financial barriers to the acquisition of medical foods and modified low-protein foods, as well as to provide access to support services required to maintain metabolic control in individuals with PKU. Research on nondietary alternatives to treatment of PKU is strongly encouraged. To achieve optimal statistical power, as well as cross-cultural applicability, it will be beneficial to use data acquired via national and international collaboration.

Cost-Benefit Analysis↗

Effect of corticosteroids for fetal maturation on perinatal outcomes. NIH Consensus Development Panel on the Effect of Corticosteroids for Fetal Maturation on Perinatal Outcomes.

OBJECTIVE: To develop a consensus on the use of antenatal corticosteroids for fetal maturation in preterm infants. PARTICIPANTS: A nonfederal, nonadvocate, 16-member consensus panel including representatives from neonatology, obstetrics, family medicine, behavioral medicine, psychology, biostatistics, and the public; 19 experts in neonatology, obstetrics, and pharmacology presented data to the consensus panel and a conference audience of approximately 500. EVIDENCE: An extensive bibliography of references was produced for the consensus panel and the conference audience using a variety of on-line databases including MEDLINE. The consensus panel met several times prior to the conference to review the literature. It also commissioned an updated meta-analysis, a neonatal registry review, and an economic analysis that were presented at the conference. The experts prepared abstracts for distribution at the conference, presented data, and answered questions from the panel and audience. The panel evaluated the strength of the scientific evidence using the grading system developed by the Canadian Task Force on the Periodic Health Examination and adapted by the US Preventive Services Task Force. CONSENSUS: The consensus panel, answering predefined consensus questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. CONSENSUS STATEMENT: The consensus panel composed a draft statement that was read in its entirety at the conference for comment. The panel released a revised statement at the end of the conference and finalized the revisions a few weeks after the conference. CONCLUSIONS: Antenatal corticosteroid therapy is indicated for women at risk of premature delivery with few exceptions and will result in a substantial decrease in neonatal morbidity and mortality, as well as substantial savings in health care costs. The use of antenatal corticosteroids for fetal maturation is a rare example of a technology that yields substantial cost savings in addition to improving health.

Betamethasone↗

Benzaldehyde, citral, and d-limonene flavor perception in the presence of casein and whey proteins.

The effect of sodium caseinate and whey protein concentrate on benzaldehyde, d-limonene, and citral flavor intensity was determined by quantitative descriptive analysis deviation from reference using a 12-member trained panel. The concentrations for the benzaldehyde, d-limonene, and citral flavor intensity references were 17.8, 53.0, and 19.8 ppm, respectively. The concentration for both protein references was .25%. Flavored protein solutions were held for 17 h at 6 degrees C and contained benzaldehyde (17.8 ppm), d-limonene (53 ppm), or citral (19.8 ppm) and 2.5% sucrose with 0, .125, .25, or .5% protein. Benzaldehyde flavor intensity declined as the whey protein concentrate concentration increased from 0 to .5%. There was no significant difference in benzaldehyde flavor intensity with casein compared with the reference. The d-limonene flavor intensity declined as the protein concentration increased. Panelists found no significant drop in citral flavor intensity with casein or whey protein. Decreased benzaldehyde and d-limonene flavor intensity in the presence of whey protein concentrate or casein may be due to nonpolar interactions (casein), interaction with nonpolar binding sites, cysteine-aldehyde condensation, or Schiff base formation (whey protein concentrate).

Acyclic Monoterpenes↗

Use of human data for the derivation of a reference dose for chlorpyrifos.

In 1998 a panel of experts met to discuss the data available on chlorpyrifos, both human and animal, and to determine the most appropriate endpoints to be used for the derivation of the reference dose (RfD). Since that time, additional data have become available on chlorpyrifos from an experimental study involving humans. Moreover, Food Quality Protection Act (FQPA) considerations need to be addressed, and the appropriate cholinesterase endpoint, whether plasma, red blood cell, peripheral nerve, or brain, has become highly debated. Therefore, Dow AgroSciences, one of the manufacturers of chlorpyrifos, convened a second panel of toxicology and medical experts on June 21, 1999, to consider the presently available scientific literature both published and unpublished on chlorpyrifos and to determine the acute and chronic toxicological RfDs for chlorpyrifos. Four questions were posed to this second panel of experts concerning the available data on chlorpyrifos. (1) Should the RfD for chlorpyrifos be based on acetylcholinesterase (AChE) inhibition or butyrylcholinesterase (BuChE) inhibition as an endpoint for adverse effect? (2) Should the RfDs for chlorpyrifos be based on the data set from three human studies, which are supported by animal data? (3) Should the FQPA safety factor be reduced to 1xbased on animal studies of pre- or postnatal toxicity? (4) If an RfD for chlorpyrifos were to be based on animal data, then is a 10-fold interspecies uncertainty factor necessary? The panel of experts concluded that: (1) inhibition of BuChE is not an adverse effect, and the RfD for chlorpyrifos should be based on AChE inhibition; (2) the RfD for chlorpyrifos should be based on the three available human studies, which are also supported by animal data; (3) the extra FQPA safety factor should be reduced to 1x, because chlorpyrifos shows no pre- or postnatal toxicity of concern at relevant human exposure conditions; and (4) the extra 10-fold safety factor for interspecies variation appears overly conservative because no differences in species sensitivity to chlorpyrifos is evident.

Acetylcholinesterase↗

[Evaluation of the system for controlling the quality of the HBsAg detection in the system of screening laboratories].

The two-stage control system, ensuring the high quality of serological investigations in the network of screening laboratories in Moscow was developed and introduced into practice. At the first stage the entry control of the quality of the test system for the detection of HbsAg, coming to the screening laboratories, is made in the reference laboratory with the use of specially developed "representative" panels, as well as the test systems for comparison ("reference" test systems). Then "minipanels" are formed from specimens included into the "representative" panels, which are used for the evaluation of the quality of laboratory investigations made in the screening laboratories. The high quality of such system for controlling the quality of the detection of HBsAg in the screening laboratories of Moscow is shown.

Evaluation Studies as Topic↗

Case triage model for the practice of telepathology.

OBJECTIVE: To implement and evaluate a practice model for telepathology. METHODS: A case triage practice model was devised in which general pathologists review all cases and refer them to subspecialists only when necessary. In 1993, the Arizona-International Telemedicine Network (AITN), a high-resolution static imaging telepathology diagnostic network, linking six sites to the University of Arizona in Tucson, began testing the model. Work flow through the network was analyzed, and diagnostic concordance was assessed in 150 surgical cases by comparing the diagnoses of the referring (transmitting) pathologists with diagnoses of the consulting (receiving) telepathologists as well as by comparing the referring pathologists' diagnoses with the consensus diagnoses reached by an independent review panel. Data analysis was controlled for subspecialty case type. Telepathologists had access to the referring pathologists' preliminary diagnoses, and the review panel had access to the original glass slides and the surgical pathology reports prior to rendering their respective diagnoses. RESULTS: The triage pathologist completed the telepathology consultation without the assistance of a subspecialty pathologist in 66% of the cases. The review panel examined the original glass slides from 134 cases by light microscopy. Concordance rates of the telepathologists' or review panel's diagnoses with the referring pathologists' diagnoses were not statistically different (93.1% v 83.6%, respectively; P > 0.05). CONCLUSION: The case triage model is suitable for the practice of telepathology. It significantly reduces the need for subspecialty pathologists. Static imaging telepathology is useful and reasonably efficient for rendering diagnostic opinions in the majority of referred cases. Tissue sampling limitations imposed by static imaging occasionally resulted in diagnostic errors.

Adult↗

A comprehensive league table of cost-utility ratios and a sub-table of "panel-worthy" studies.

OBJECTIVES: The authors compiled a comprehensive league table of cost/QALY ratios, and a standardized table of analyses satisfying selected Reference Case criteria from the USPHS Panel on Cost-Effectiveness in Health and Medicine. METHODS: They identified 228 cost-utility analyses (CUAs) through literature searches, and abstracted data on methods and cost-utility ratios. The subset of "Panel-worthy" analyses used: a societal or broad health-care perspective, community or patient preference weights, net costs, incremental comparisons, and discounting of costs and QALYs. RESULTS: The 228 CUAs included ratios for 647 interventions, ranging from cost-saving to $52,000,000/QALY (median = $12,000/QALY). The standardized table presents 112 ratios that met the "Panel-worthy" criteria, with articles published in recent years more likely to meet all of the criteria. CONCLUSIONS: The comprehensive league table (available on the Web) provides a useful reference, but ratios may not be comparable because of methodologic variations. The standardized table focuses on studies meeting basic methodologic criteria, potentially allowing for better comparison with future Reference Case analyses. Future studies should investigate the quality of analyses' underlying assumptions in addition to whether certain key procedural protocols were met.

Adolescent↗

A measuring system for facial aesthetics in Caucasian adolescents: reproducibility and validity.

A new measuring system to judge facial aesthetics in young Caucasians is presented. The system uses sets of three photographs (one frontal, one three-quarter smiling, and one lateral) as a stimulus. Scores are performed on a visual analogue scale (VAS) with separate sets of reference photographs for girls and boys. The choice of the reference photographs was based on a panel evaluation of facial aesthetics of 40 boys and 40 girls from the archive of the orthodontic department. Reproducibility of the new measuring system was tested on a series of photographic sets (one frontal, one three-quarter smiling, and one lateral view) of 64 patients, using a panel of 78 adult laymen and 89 professionals. The panel members assessed these sets of photographs on a VAS, in relation to the reference sets. The system was shown to be reproducible. Although the intra-observer reproducibility was low, the reliability coefficient was excellent (Cronbach's alpha > or = 0.98). Validity was tested by comparing the scores on the new scales with those of the three-quarter smiling photographic views on an earlier published scale. The correlation between the ratings on the new measuring system and the earlier published scale was 0.82 for laymen and 0.77 for professionals. The new system is simple and flexible in its use, and reproducible and valid for assessing facial aesthetics in young Caucasians. The system can be used in further investigations on the evaluation of facial aesthetics.

Adolescent↗

Guidelines on selection of laboratory tests for monitoring the acute phase response. International Committee for Standardization in Haematology (expert panel on blood rheology).

These guidelines refer to laboratory tests for monitoring changes in acute phase proteins in patients with an inflammatory response to tissue damage. Quantitative measurements of acute phase proteins are a valuable indicator of the presence, extent, and response of inflammation to treatment. When short term (less than 24 hours) changes in the inflammatory response are expected, quantitative assay of C reactive protein is the test of choice. The hyperproteinaemia that develops in response to a longer term (more than 24 hours) inflammatory response is complex and may vary from one disease to another. A test that is sensitive to the combined effect of several plasma proteins is therefore indicated, and appropriate tests include the erythrocyte sedimentation rate and plasma viscosity--the latter having several advantages. Tests for monitoring short term and long term changes in acute phase proteins are complementary and should be used for different clinical purposes; no one test is ideal for all clinical situations. A quality control programme is an essential component of laboratory tests for monitoring the acute phase response.

Acute-Phase Proteins↗

National Institutes of Health Consensus Development Conference Statement: phenylketonuria: screening and management, October 16-18, 2000.

OBJECTIVE: To provide health care providers, patients, and the general public with a responsible assessment of currently available data regarding screening for and management of phenylketonuria (PKU). PARTICIPANTS: A nonfederal, nonadvocate, 14-member panel representing the fields of pediatrics, genetics, human development, public policy, nursing, and molecular physiology and including patient representatives. In addition, 19 experts in pediatrics, medical genetics, psychology, pediatric neurology, biochemical and molecular genetics, and gene therapy presented data to the panel and to a conference audience of 312. EVIDENCE: The literature was searched using Medline for January 1980 through July 2000, and an extensive bibliography of 3394 references was provided to the panel. Experts prepared abstracts for their conference presentations with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed its conclusions based on the scientific evidence presented in open forum and the scientific literature. The panel composed a draft statement, which was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. The draft statement was made available on the World Wide Web immediately after its release at the conference and was updated with the panel's final revisions. The statement is available at http://consensus.nih.gov. CONCLUSIONS: Genetic testing for PKU has been in place for almost 40 years and has been very successful in preventing severe mental retardation in thousands of children and adults. Metabolic control is necessary across the lifespan of individuals with PKU. A comprehensive, multidisciplinary, integrated system is needed to delivery of care to individuals with PKU. Greatly needed are consistency and coordination between screening, treatment, data collection, and patient support programs. There should be equal access to culturally sensitive, age-appropriate treatment programs. Ethically sound, specific policies for storage, ownership, and use in future studies of archived samples remaining from PKU testing should be established. Research into the pathophysiology of PKU and relationship to genetic, neural, and behavioral variation is strongly encouraged. Uniform policies must be established to remove financial barriers to the acquisition of medical foods and modified low-protein foods and to provide access to support services needed to maintain metabolic control in individuals with PKU. Research on nondietary alternative treatments for PKU is strongly encouraged. To achieve optimal statistical power and cross-cultural applicability, it will be beneficial to use data acquired via national and international collaboration.phenylketonuria, hyperphenylalanimea, phenylketonuria screening, phenylalanine-restricted diet, maternal phenylketonuria, newborn screening, phenylalanine monitoring, phenylketonuria outcomes.

Adult↗

Gaucher disease. Current issues in diagnosis and treatment. NIH Technology Assessment Panel on Gaucher Disease.

OBJECTIVE: To provide physicians with a responsible assessment of the diagnosis and treatment of Gaucher disease. PARTICIPANTS: A nonfederal, nonadvocate, 14-member panel representing the fields of pediatrics, obstetrics and gynecology, genetics, endocrinology, molecular biology, internal medicine, and biostatistics. In addition, 30 experts in genetics, pediatrics, neurology, obstetrics and gynecology, orthopedics, hematology, genetic counseling, clinical pathology, and epidemiology presented data to the panel and a conference audience of 230 during a 1 1/2 public session. Questions and statements from conference attendees were considered during the open session. Closed deliberations by the panel occurred during the remainder of the second day and the morning of the third. EVIDENCE: The literature was searched through MEDLINE, and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and on the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. CONCLUSIONS: Despite the success of enzyme therapy, treatment is limited by the cost of the agent. This makes it imperative to determine the lowest effective initial and maintenance doses, to define the appropriate clinical indications for treatment, and to establish uniform methods for optimize outcome assessment. The value of treatment for asymptomatic individuals has not been determined. General population screening for affected individuals and for carriers is not appropriate at this time. As a prototype for all rare diseases, the plight of patients with Gaucher disease raises difficult financial and ethical issues, which we as a society must address.

Clinical Enzyme Tests↗

Integration of behavioral and relaxation approaches into the treatment of chronic pain and insomnia. NIH Technology Assessment Panel on Integration of Behavioral and Relaxation Approaches into the Treatment of Chronic Pain and Insomnia.

OBJECTIVE: To provide physicians with a responsible assessment of the integration of behavioral and relaxation approaches into the treatment of chronic pain and insomnia. PARTICIPANTS: A nonfederal, nonadvocate, 12-member panel representing the fields of family medicine, social medicine, psychiatry, psychology, public health, nursing, and epidemiology. In addition, 23 experts in behavioral medicine, pain medicine, sleep medicine, psychiatry, nursing, psychology, neurology, and behavioral and neurosciences presented data to the panel and a conference audience of 528 during a 1 1/2-day public session. Questions and statements from conference attendees were considered during the open session. Closed deliberations by the panel occurred during the remainder of the second day and the morning of the third day. EVIDENCE: The literature was searched through MEDLINE, and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. ASSESSMENT PROCESS: The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. CONCLUSIONS: A number of well-defined behavioral and relaxation interventions now exist and are effective in the treatment of chronic pain and insomnia. The panel found strong evidence for the use of relaxation techniques in reducing chronic pain in a variety of medical conditions as well as strong evidence for the use of hypnosis in alleviating pain associated with cancer. The evidence was moderate for the effectiveness of cognitive-behavioral techniques and biofeedback in relieving chronic pain. Regarding insomnia, behavioral techniques, particularly relaxation and biofeedback, produce improvements in some aspects of sleep, but it is questionable whether the magnitude of the improvement in sleep onset and total sleep time are clinically significant.

Behavior Therapy↗

Physical activity and cardiovascular health. NIH Consensus Development Panel on Physical Activity and Cardiovascular Health.

OBJECTIVE: To provide physicians and the general public with a responsible assessment of the relationship between physical activity and cardiovascular health. PARTICIPANTS: A nonfederal, nonadvocate, 13-member panel representing the fields of cardiology, psychology, exercise physiology, nutrition, pediatrics, public health, and epidemiology. In addition, 27 experts in cardiology, psychology, epidemiology, exercise physiology, geriatrics, nutrition, pediatrics, public health, and sports medicine presented data to the panel and a conference audience of 600 during a 2-day public session. Questions and statements from conference attendees were considered during the open session. Closed deliberations by the panel occurred during the remainder of the second day and the morning of the third day. EVIDENCE: The literature was searched through MEDLINE and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. CONSENSUS STATEMENT: The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. There-after, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. CONCLUSIONS: All Americans should engage in regular physical activity at a level appropriate to their capacity, needs, and interest. Children and adults alike should set a goal of accumulating at least 30 minutes of moderate-intensity physical activity on most, and preferably all, days of the week. Most Americans have little or no physical activity in their daily lives, and accumulating evidence indicates that physical inactivity is a major risk factor for cardiovascular disease. However, moderate levels of physical activity confer significant health benefits. Even those who currently meet these daily standards may derive additional health and fitness benefits by becoming more physically active or including more vigorous activity. For those with known cardiovascular disease, cardiac rehabilitation programs that combine physical activity with reduction in other risk factors should be more widely used.

Adult↗

Electronic noses in food analysis.

Gas sensor array technology combined with multivariate data processing methods as artificial neural network has been demonstrated to have a promising potential for rapid non-destructive analysis of food quality. It may be applicable in quality control of raw material, food processing or products. This technique cannot completely replace reference methods like the use of sensory panels as the technique requires a frequent calibration against some valid reference method. As with all new techniques there remain some basic problems to be solved concerning sample handling and instrumental performance. The emerging research activity in the development of chemical sensors including hardware and software combined with applied research makes it realistic to expect applications with this technique implemented on-line in the food industry in near future. In particular, promising applications on meat seem to be within the field of spoilage, off-flavor, sensory analysis and fermentation processes.

Animals↗

The influence of diet crude protein level on odour and ammonia emissions from finishing pig houses.

Feed trials were carried out to assess the influence of crude protein content in finishing pig diets on odour and ammonia emissions. Eight pigs (4 boars and 4 gilts), average initial weight 70.8 kg (s.e. 3.167) were housed in two pens that were isolated from the rest of a pig house at University College Dublin Research Farm, Newcastle, Dublin, Ireland. Four diets containing 130, 160, 190 and 220 g x kg(-1) crude protein were fed during six four-week feeding periods (one treatment per room). The first week of the feeding periods served to allow odour build up in the pens and as a dietary adjustment period. The pens had partially slatted floors that were cleaned and had all the manure removed after each four-week period. Odour and ammonia concentrations were measured on days 9, 14, 16, 21 and 23 of each trial period. Odour samples were collected in Nalophan bags and analysed for odour concentration using an ECOMA Yes/No olfactometer. The odour threshold concentration was calculated according to the response of the olfactometry panel members and was displayed in Ou(E)m(-3), which referred to the physiological response from the panel equivalent to that elicited by 40 ppbv(-1) n-butanol evaporated in 1 m(3) of neutral gas. Ammonia concentrations in the ventilation air were measured using Dräger tubes. The odour emission rates per animal for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 12.1, 13.2, 19.6 and 17.6 Ou(E)s(-1)animal(-1), respectively (P<0.01). The odour emission rate per livestock unit (500 kg) for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 77.6, 80.0, 115.8 and 102.9 Ou(E)s(-1)LU(-1), respectively (P<0.01). The ammonia emission rates per animal for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 3.11, 3.89, 5.89 and 8.27 g x d(-1)animal(-1), respectively (P 0.05). Manipulation of dietary crude protein levels would appear to offer a low cost alternative, in relation to end-of-pipe treatments, for the abatement of odour and ammonia emissions from finishing pig houses.

Air Pollutants↗