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AIM: Following previous research on improving the cleaning of crates used to transport broiler chickens from the farm to the abattoir, a demonstration project was undertaken to investigate improvements in crate washing on a commercial scale. METHODS AND RESULTS: The soak tank of a conventional crate washing system was replaced with a high-performance washer fitted with high-volume, high-pressure nozzles. The wash water could be heated, and a greatly improved filtration system ensured that the nozzles did not lose performance or become blocked. Visual cleanliness scores and microbial counts were determined for naturally contaminated crates which had been randomly assigned to different cleaning protocols. CONCLUSIONS: When a combination of mechanical energy, heat and chemicals (i.e. detergent and disinfectant) was used, the results showed significant improvements to crate cleaning. Reductions of up to 3·6 and 3·8 log10 CFU per crate base were achieved for Campylobacter and Enterobacteriaceae, respectively, along with a marked improvement in visual cleanliness. SIGNIFICANCE AND IMPACT OF THE STUDY: Broiler transport crates may become heavily contaminated with faeces and this may contribute to the spread of disease between farms. The results of this trial may be of use in reducing the spread of zoonotic pathogens in the poultry meat supply chain.

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Cardiorespiratory fitness is often assessed through measures of maximal oxygen uptake, sometimes referred to as aerobic capacity (26). The importance of adequate aerobic capacity for optimal health has been observed in numerous studies examining both adults (1,2,20) and children (17,24). An increased risk of overweight and metabolic syndrome in adults can result from a reduction in aerobic capacity from childhood to adolescence (4,11).

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The Toronto Charter for Physical Activity (2010) and several national physical activity plans advocate sports participation as an important part of population targeted physical activity for youth. Emerging research evidence also suggests that sports participation during adolescents is linked to significant positive correlations with academic and behavioral performance. The purpose of this study was to compare academic and behavioral performance between male and female public school athletes (Total N=11,139; 38% Female) and non-athletes (Total N=23,891; 52% Female) in a convenient, ethnicity diverse, sample (grades 7-12) from the state of Texas (USA). We examined the passing rates of individual athletes and non-athletes on standardized tests (Texas Assessment of Knowledge and Skills, TAKS) for math, language arts, reading, writing, science, and social studies. We also examined the percentage of athletes and non-athletes for being "at risk," for dropping out of school and for the total average number of disciplinary actions. Chi-Square statistical analyses comparing athletes to non-athletes showed that athletes scored significantly better (p<0.05) on all standardized tests compared to non-athletes (passing rate ranges ranged from 77.1% to 92.9% versus 27.7% to 66.5% respectively). Athletes were at lower risk for dropout compared to non-athletes (35.6% versus 49.24%; p<0.05), and they had fewer disciplinary actions (mean of 0.85 per athletes per year versus 1.23 for non-athletes; ANOVA, p<0.05). Our results support the research findings of others that participation in school sports is positively correlated to better academic and behavioral performances for athletes compared to non-athletes.

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Texas Senate Bill 530 (2007) mandated fitness assessment as part of the annual K-8 Physical Education (PE) curricula, yet no studies have reported interventions designed to improve and quantify individual student passing rates or individual school performance. Students (Total 2008-2010 N=1484; 729 females, 755 males; mean age = 11.85 y; mean BMI = 22.69 or > 90%-tile, overweight) were evaluated on individual FITNESSGRAM® performances in a cross-sectional analysis of 6th graders comparing baseline scores (year 1) with outcomes of a physical activity intervention in years 2 and 3. Students participated in regular PE classes (including campus wellness center activities) with a once a week focus (FITNESSGRAM® Friday) on improving mile run scores and other assessment scores. Students significantly improved FITNESSGRAM® scores following the PE intervention to levels similar to state reported averages. On average, boys improved their pushups by 32.7%, trunk lift by 17.4% and mile run times by 29.5%. Averages for girls improved by 15.4% for pushups, 6.7% for truck lift, and by 38.6% for the mile run. The percentage of boys in our study achieving all six FITNESSGRAM® tests in the HFZ was 3% at baseline and 22% following intervention. The percentage of girls meeting the criteria for the HFZ on all six FITNESSGRAM® tests was 4.5% at baseline and 20% following intervention. This study provides a potential model for fitness success in other middle school PE interventions, in Texas and the nation.

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1. Small sections cut from commercial crates used to transport live poultry to the processing plant were artificially contaminated with effluent taken from a commercial crate-cleaning system. 2. Laboratory trials, involving the immersion of these sections in an ultrasonic water bath (4 kW energy) showed that aerobic plate counts (APC) and counts of Enterobacteriaceae were progressively reduced as the immersion time was increased from 0 to 120 s and the water temperature raised from 35 to 58 degrees C. 3. In subsequent trials at a processing plant, using commercially cleaned crates, there was relatively little effect of ultrasound (or pressure washing) on the biofilm present. However, ultrasonic treatment in combination with an immersion temperature of 60 degrees C reduced counts of Enterobacteriaceae to below the detection limit (log(10) 2.3 cfu) within 1 to 3 min, while APC were reduced by >2 log(10) units after 3 min. 4. It was concluded that ultrasonic treatment has a possible role in the crate-cleaning process, when used in conjunction with higher immersion temperatures. In this way, it could contribute significantly to hygiene control.

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1. The present systems for cleaning the plastic crates (drawers) used to transport live poultry to the processing plant are known to be inadequate for removing microbial contamination. 2. To investigate possible improvements, a mobile experimental rig was constructed and operated in the lairage of a poultry processing plant. The cleaning rig could simulate the conditions of commercial cleaning systems and utilise freshly emptied crates from the processing plant. 3. The aim of the study was to improve cleaning by enhancing the removal of adherent organic material on the crates and by reducing microbial contamination by at least 4 log(10) units. 4. Trials showed that the most effective treatments against Campylobacter were either (a) the combination of soaking at 55 degrees C, brushing for 90 s, washing for 15 s at 60 degrees C, followed by the application of disinfectant (Virkon S in this study) or (b) the use of ultrasound (4 kW) at 65 degrees C for 3 to 6 min, with or without mechanical brushing of crates. 5. Both of these treatments also achieved a 4 log(10) reduction or more in the counts of Enterobacteriaceae but were less effective in reducing aerobic plate counts. 6. It was noted that there was little correlation between the visual assessment of crate cleanliness and microbiological counts. 7. It was concluded that the demonstrated enhanced cleaning could contribute significantly to overall hygiene control in poultry meat production.

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This paper describes a novel method of measuring the contamination of raw foods with airborne bacteria during primary processing. To demonstrate the approach, this study aimed to quantify the role of airborne bacteria in the contamination of broiler chicken carcasses undergoing processing in an evisceration room. Settle plates and broiler carcasses were exposed to the evisceration room air or to ultra-clean air provided by a high efficiency particulate air (HEPA) unit located within the room. The use of ultra-clean air reduced the total aerobic counts on horizontal settle plates by 68-fold, and on vertical settle plates by 14-fold. The use of ultra-clean air had no significant effect on the total aerobic counts on carcasses as measured by sponging (3.5 log(10) CFU cm(-2)) or skin excision (4.0 log(10) CFU cm(-2)). The novel approach was able to show that the carcasses entering the room were so heavily contaminated that the airborne bacteria in the evisceration room contributed less than 1% of the total numbers of bacteria on the carcasses.

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The study aimed to identify sources of campylobacter in 10 housed broiler flocks from three United Kingdom poultry companies. Samples from (i) the breeder flocks, which supplied the broilers, (ii) cleaned and disinfected houses prior to chick placement, (iii) the chickens, and (iv) the environments inside and outside the broiler houses during rearing were examined. Samples were collected at frequent intervals and examined for Campylobacter spp. Characterization of the isolates using multilocus sequence typing (MLST), serotyping, phage typing, and flaA restriction fragment length polymorphism typing was performed. Seven flocks became colonized during the growing period. Campylobacter spp. were detected in the environment surrounding the broiler house, prior to as well as during flock colonization, for six of these flocks. On two occasions, isolates detected in a puddle just prior to the birds being placed were indistinguishable from those colonizing the birds. Once flocks were colonized, indistinguishable strains of campylobacter were found in the feed and water and in the air of the broiler house. Campylobacter spp. were also detected in the air up to 30 m downstream of the broiler house, which raises the issue of the role of airborne transmission in the spread of campylobacter. At any time during rearing, broiler flocks were colonized by only one or two types determined by MLST but these changed, with some strains superseding others. In conclusion, the study provided strong evidence for the environment as a source of campylobacters colonizing housed broiler flocks. It also demonstrated colonization by successive campylobacter types determined by MLST during the life of a flock.

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1. A readily identifiable strain of Escherichia coli K12 was used as a 'marker' organism to determine the sources, routes and patterns of microbial cross-contamination during mechanical defeathering of broiler chicken carcases. 2. Inoculation of scald water with the marker organism led to a relatively even pattern of carcase contamination during subsequent defeathering. Microbial cross-contamination was greater by this route of inoculation than by either surface inoculation of a 'seeder' carcase or oral inoculation of a live bird one day before slaughter. 3. Dispersal of the marker organism was strongly influenced by the mechanical action of the defeathering machines. Forward transmission of the marker occurred by aerosol or large airborne droplets and particulates such as feathers. Moving carcases through the defeathering machines when these were non-operational clearly reduced backward transmission of the marker. 4. Although microbial dispersal was unaffected by increasing the spacing between individual carcases or installing a water curtain at the entry and exit of the defeathering machines, shielding of carcases with aluminium baffles reduced counts of the marker organism from contaminated carcases by > 90%. 5. The results imply that microbial cross-contamination of broiler chicken carcases during defeathering occurs mainly via the airborne route, which could be contained by physical means.

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1. The extent of cross contamination between carcases and the dispersal of micro-organisms to the environs during defeathering was measured in a commercial processing plant. 2. Defeathering reduced the numbers of a marker organism, a nalidixic acid-resistant strain of Escherichia coli K12, on inoculated carcases but dispersed the organism on to preceding and following carcases. 3. The pattern of microbial dispersal during defeathering was similar for naturally occurring bacteria on the carcase, for example, total aerobic counts and counts of presumptive coliforms, suggesting that the marker organism mimics the natural situation realistically. 4. The majority of feathers, together with micro-organisms, were removed during the first 10 s of the defeathering process, which was completed in 45 s, indicating that control measures to minimise cross contamination would be most effective if applied in the early stages of the process. 5. The method of defeathering used by the machine influenced the pattern of microbial dispersal and the extent of cross contamination to other carcases on the same processing line.

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To determine the metabolic and cardiovascular responses of aerobic dance bench stepping (ADBS) at commonly used cadences and bench heights, 30 women (19-47 years of age) performed a graded maximal treadmill test and four 8-minute submaximal ADBS routines. Subjects followed identical videotape sequences of basic ADBS movements at cadences of 125 and 130 beats.min(-1) at bench heights of 6 and 8 in. Physiological measurements were taken during each minute of each test. Mean values calculated from the last 3 minutes were used for data analysis. Although there were no physiological differences between ADBS at the 2 cadences, there were significant physiological differences between ADBS at the 2 bench heights. On average, a 2-in. increase in bench height, increased heart rate, VO2, and rating of perceived exertion by 10 beats.min(-1), 3.09 ml.kg(-1) min(-1), and 1.53, respectively. In conclusion, it appears that bench height is more of a factor than cadence in increasing metabolic cost of ADBS. Results from this study provide information about the energy cost of ADBS at the common bench heights and cadences used in this study and, therefore, may be used to help aerobic participants select the proper bench height and cadence combination to control body weight and develop cardiorespiratory fitness safely and effectively.

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Two series of experiments were carried out to investigate methods of reducing contamination of lamb carcasses in low-throughput abattoirs, where cradle dressing is normally employed. In the first series, cradle design and pelt removal procedure were investigated, and a method was developed for assessing gross visible contamination. Significant improvements in microbiological and gross visible contamination (P < 0.01) were achieved by procedural changes only; modifications to the cradle design had no effect. In the second series of experiments, two improved methods of pelt removal and the effect of hand washing prior to carcass contact during the pelt removal procedure were investigated. The improved methods comprised a Frame system, in which the pelt was removed in a manner similar to that in a high-throughput inverted line, and a Hybrid system, in which the pelt was removed from the forequarters on a conventional cradle before the carcass was suspended in an "inverted" vertical position for removal of the pelt from the abdomen and hindquarters. The results of microbiological and gross visible contamination from these methods, with and without hand washing, were compared with the conventional Cradle method of pelt removal. Both the Hybrid and Frame systems had significantly less microbiological and gross visible contamination (P < 0.01). However, hand washing had no significant effect on the level of carcass contamination for all three methods of pelt removal. Greatest reductions in microbiological and gross visible contamination were achieved using techniques that minimized hand contact with the carcass during pelt removal by adoption of inverted dressing procedures. Equipment redesign did not reduce carcass contamination.

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1. An experimental rig, designed and built to simulate conditions found in commercial poultry chilling systems, was used to investigate the effects of varying air temperature and chilling duration, and the effect of chlorinated water sprays, on the microbial load present on the skin and in the body cavity of freshly eviscerated poultry carcases; deep muscle and skin temperatures were monitored during chilling at three different temperatures. 2. During dry chilling for 2 h, total viable microbe counts (TVC) and counts of coliforms and pseudomonads from the body cavity fell by between half and one log unit; smaller reductions were observed in samples from the breast skin. 3. The situation changed when chlorinated water sprays (50, 100 or 250 ppm available chlorine) were applied for the first hour of chilling; spraying carcases enhanced the reduction in numbers on the skin; the effect was most pronounced with 250 ppm chlorine; conversely in the body cavity, the general effects of sprays was to increase contamination by up to one log unit. 4. There was no evidence that sprays increased the rate of chilling. 5. When carcases were held overnight in the rig at 11 degrees C after chilling, microbe counts on dry-chilled carcases remained stable, but increased on carcases that had been sprayed with chlorinated water.

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Studies of the metabolic and physiological changes that bears undergo during hibernation have, for the most part, supported the paradigm that bears use only fatty tissues as a metabolic substrate during hibernation. This study was performed to document the extent of protein loss and alteration of muscle-fiber characteristics of selected muscles in black bears during winter dormancy. Muscle biopsies were removed from the gastrocnemius and biceps femoris from seven free-ranging female black bears on the Uncompahgre Plateau in west-central Colorado. Six of the seven bears produced cubs during the hibernating season. Muscle samples were collected from the left hind limb shortly after bears entered their dens (fall), and additional samples were collected from the right hind limb just prior to bears leaving their dens (spring). Protein concentration, fast- and slow-twitch muscle-fiber ratios and muscle-fiber cross-sectional areas, and citrate synthase activity were measured in the laboratory. While protein concentration decreased in both muscles during the hibernation period, it was lower than predicted for lactating females. In addition, muscle-fiber number and cross-sectional area were unchanged in these muscles, suggesting only limited muscle atrophy. In support of these observations, there was a moderate but significant increase in the proportion of fast-twitch fibers only in the biceps femoris, with a concomitant decrease in citrate synthase activity, but no alteration of the fiber ratio in the gastrocnemius during hibernation. These findings suggest that hibernating bears, particularly lactating females, do use some protein, in concert with fat catabolism, as a metabolic substrate and as a source of water. However, the extent of this protein use is moderate and is associated with limited alteration of muscle structure, characteristic of disuse atrophy.

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Attention deficit disorder (ADHD) is a complex biobehavioral phenotype which affects up to 8% of the general population and often impairs social, academic, and job performance. Its origins are heterogeneous, but a significant genetic component is suggested by family and twin studies. The murine strain, coloboma, displays a spontaneously hyperactive phenotype that is responsive to dextroamphetamine and has been proposed as a genetic model for ADHD. Coloboma is a semi-dominant mutation that is caused by a hemizygous deletion of the SNAP-25 and other genes on mouse chromosome 2q. To test the possibility that the human homolog of the mouse coloboma gene(s) could be responsible for ADHD, we have carried out linkage studies with polymorphic markers in the region syntenic to coloboma (20p11-p12). Five families in which the pattern of inheritance of ADHD appears to be autosomal dominant were studied. Segregation analysis of the traits studied suggested that the best fitting model was a sex-influenced, single gene, Mendelian pattern. Several genetic models were evaluated based on estimates of penetrance, phenocopy rate, and allele frequency derived from our patient population and those of other investigators. No significant linkage was detected between the disease locus and markers spanning this chromosome 20 interval.

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Menkes syndrome in humans is an X-linked disorder characterized in part by abnormal copper transport, cellular copper sequestration, and defective crosslinking of collagen and elastin. A decrease in the functional activity of lysyl oxidase, a cuproenzyme, is thought in part to be responsible for the decreased crosslinking of collagen and elastin. It has also been suggested that low levels of lysyl oxidase activity may occur secondarily to disturbances in intracellular copper translocation and consequently impaired incorporation of copper into lysyl oxidase. Herein, we examine the expression and accumulation of selected extracellular matrix proteins in fibroblasts from a Menkes patient, as well as fibroblasts from the tortoiseshell (MoTo/y) mouse. The MoTo mutation is an allele of the mottled (Mo) locus, which is considered to be a murine analog of the human Menkes locus. In both Menkes and tortoiseshell fibroblasts, levels of lysyl oxidase mRNA transcripts were less than 15% of levels for corresponding controls. The level of elastin mRNA transcripts was also markedly lower in both cell lines in comparison to controls. In contrast, the levels of procollagen Type I mRNA were similar or enhanced in Menkes and MoTo/y fibroblasts compared to their respective controls. Consequently, we conclude that the connective tissue defects associated with Menkes syndrome and those occurring in mottled mouse mutants involve more than abnormal copper utilization in the formation of lysyl oxidase holoenzyme. Based on the present studies in cell culture, the production of essential enzymes and matrix proteins, such as lysyl oxidase and elastin, appear to be altered at the level of transcription or mRNA turnover.

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The possible utility of Wechsler's Deterioration Index (WDI) in analyzing children's Wechsler Intelligence Scale for Children-Revised (WISC-R) results was explored in this study. Clinical records of children with learning disabilities (LD) and children with attention deficit-hyperactivity disorder (ADHD) were reviewed to determine if the WDI predicted the presence or severity of the disorders. The ages of the children ranged from 6 to 14. In two independent samples of children with LD (n = 35 and n = 26), the WDI did not predict LD status or severity. The LD samples were mostly male--85% and 57%, respectively. However, the WDI scores did significantly distinguish children with ADHD (n = 10) from nondisabled children (n = 10). The results were cross-validated on an independent sample of children with ADHD (n = 17) when compared to non-ADHD children (n = 22) who experienced significant behavioral difficulties. The ADHD samples were also mostly male--90% and 89%, respectively. The WDI classified only 59% of the children with ADHD and 86% of the non-ADHD children correctly. It is recommended that the WDI be considered a developmental index rather than a deterioration index in children. It is also recommended that significant WDI elevation (greater than .20) be considered to raise the question of ADHD, rather than simply yielding a diagnosis of ADHD.

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