94 research outputs found

    Temperature and Humidity Profiles of Broiler Houses with Experimental Conventional and Tunnel Ventilation Systems

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    This article describes the spatial and diurnal patterns of air temperature and relative humidity (RH) in commercial-scale broiler houses (12 ¥ 122 m, 40 ¥ 400 ft) using experimental conventional and tunnel heating, cooling, and ventilation systems. The experimental broiler houses used 76-cm (2.5-ft) side curtains and combined mechanical and natural ventilation. Heating was provided by propane brooders and space furnaces. Cooling was accomplished with side-mounted cooling fans and misting nozzles in the conventional houses, but with fans and evaporative cooling pads in the tunnel houses. Interior mixing fans, arranged to circulate air in a “racetrack” fashion, were used in the tunnel houses

    Weight goals, disordered eating behaviors, and BMI trajectories in US young adults

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    BACKGROUND: Community sample data indicate that weight control efforts in young adulthood may have associations with greater increases in body mass index (BMI) over time. OBJECTIVE: To determine the prospective associations between weight goals and behaviors in young adults and BMI trajectories over 15-year follow-up using a nationally representative sample. DESIGN: Longitudinal cohort data collected from 2001 to 2018 of the National Longitudinal Study of Adolescent to Adult Health. PARTICIPANTS: Young adults aged 18–26 years old at baseline stratified by gender and BMI category. MAIN MEASURES: Predictors: weight goals, any weight loss/maintenance behaviors, dieting, exercise, disordered eating behaviors. Outcomes: BMI at 7- and 15-year follow-up. KEY RESULTS: Of the 12,155 young adults in the sample (54% female, 32% non-White), 33.2% reported a goal to lose weight, 15.7% to gain weight, and 14.6% to maintain weight. In unadjusted models, all groups have higher mean BMI at 7- and 15-year follow-up. In mixed effect models, goals to lose weight in men with BMI < 18.5 (5.94 kg/m2 ; 95% CI 2.58, 9.30) and goals to maintain weight in men with BMI ≥ 25 (0.44; 95% CI 0.15, 0.72) were associated with greater BMI increase compared to no weight goal. Engaging in disordered eating behaviors was associated with greater BMI increase in men with BMI < 18.5 (5.91; 2.96, 8.86) and women with 18.5 ≤ BMI < 25 (0.40; 0.16, 0.63). Dieting (− 0.24; − 0.41, − 0.06) and exercise (− 0.31; − 0.45, − 0.17) were associated with lower BMI increase in women with 18.5 ≤ BMI < 25. In women with BMI < 18.5, dieting was associated with greater BMI increase (1.35; 0.33, 2.37). CONCLUSIONS: Weight control efforts may have variable effects on BMI over time by gender and BMI category. These findings underscore the need to counsel patients on the effectiveness of weight control efforts and long-term weight management

    Molecular and cellular mechanisms underlying the evolution of form and function in the amniote jaw.

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    The amniote jaw complex is a remarkable amalgamation of derivatives from distinct embryonic cell lineages. During development, the cells in these lineages experience concerted movements, migrations, and signaling interactions that take them from their initial origins to their final destinations and imbue their derivatives with aspects of form including their axial orientation, anatomical identity, size, and shape. Perturbations along the way can produce defects and disease, but also generate the variation necessary for jaw evolution and adaptation. We focus on molecular and cellular mechanisms that regulate form in the amniote jaw complex, and that enable structural and functional integration. Special emphasis is placed on the role of cranial neural crest mesenchyme (NCM) during the species-specific patterning of bone, cartilage, tendon, muscle, and other jaw tissues. We also address the effects of biomechanical forces during jaw development and discuss ways in which certain molecular and cellular responses add adaptive and evolutionary plasticity to jaw morphology. Overall, we highlight how variation in molecular and cellular programs can promote the phenomenal diversity and functional morphology achieved during amniote jaw evolution or lead to the range of jaw defects and disease that affect the human condition

    Insight on genes affecting tuber development in potato upon <i>Potato spindle tuber viroid</i> (PSTVd) infection

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    Potato (Solanum tuberosum L) is a natural host of Potato spindle tuber viroid (PSTVd) which can cause characteristic symptoms on developing plants including stunting phenotype and distortion of leaves and tubers. PSTVd is the type species of the family Pospiviroidae, and can replicate in the nucleus and move systemically throughout the plant. It is not well understood how the viroid can affect host genes for successful invasion and which genes show altered expression levels upon infection. Our primary focus in this study is the identification of genes which can affect tuber formation since viroid infection can strongly influence tuber development and especially tuber shape. In this study, we used a large-scale method to identify differentially expressed genes in potato. We have identified defence, stress and sugar metabolism related genes having altered expression levels upon infection. Additionally, hormone pathway related genes showed significant up- or down-regulation. DWARF1/DIMINUTO, Gibberellin 7-oxidase and BEL5 transcripts were identified and validated showing differential expression in viroid infected tissues. Our study suggests that gibberellin and brassinosteroid pathways have a possible role in tuber development upon PSTVd infection

    Transgenesis in Animal Agriculture: Addressing Animal Health and Welfare Concerns

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    The US Food and Drug Administration’s final Guidance for Industry on the regulation of transgenesis in animal agriculture has paved the way for the commercialization of genetically engineered (GE) farm animals. The production-related diseases associated with extant breeding technologies are reviewed, as well as the predictable welfare consequences of continued emphasis on prolificacy at the potential expense of physical fitness. Areas in which biotechnology could be used to improve the welfare of animals while maintaining profitability are explored along with regulatory schema to improve agency integration in GE animal oversight

    Accuracy of Broiler Activity Index as Affected by Sampling Time Interval

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    Different time intervals between consecutive images have been used to determine broiler activity index (AI). However, the accuracy of broiler AI as affected by sampling time interval remains to be explored. The objective of this study was to investigate the effect of the sampling time interval (0.04, 0.2, 1, 10, 60, and 300 s) on the accuracy of broiler AI at different bird ages (1&ndash;7 weeks), locations (feeder, drinker, and open areas) and times of day (06:00&ndash;07:00 h, 12:00&ndash;13:00 h, and 18:00&ndash;19:00 h). A ceiling-mounted camera was used to capture top-view videos for broiler AI calculations. The results show that the sampling time interval of 0.04 s yielded the highest broiler AI because more bird motion details were captured at this short time interval. The broiler AIs at longer time intervals were 1&ndash;99% of that determined at the 0.04-s interval. The broiler AI at 0.2-s interval showed an acceptable accuracy with 80% less computational resources. Broiler AI decreased as birds aged but increased after week 4 at the drinker area. Broiler AI was the highest at the open area for weeks 1&ndash;4 and at the feeder and drinker areas for weeks 5&ndash;7. It is concluded that the accuracy of broiler AI was significantly affected by sampling time intervals. Broiler AI in commercial housing showed both temporal and spatial variations

    Characterizing Sounds of Different Sources in a Commercial Broiler House

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    Audio data collected in commercial broiler houses are mixed sounds of different sources that contain useful information regarding bird health condition, bird behavior, and equipment operation. However, characterizations of the sounds of different sources in commercial broiler houses have not been well established. The objective of this study was, therefore, to determine the frequency ranges of six common sounds, including bird vocalization, fan, feed system, heater, wing flapping, and dustbathing, at bird ages of week 1 to 8 in a commercial Ross 708 broiler house. In addition, the frequencies of flapping (in wing flapping events, flaps/s) and scratching (during dustbathing, scratches/s) behaviors were examined through sound analysis. A microphone was installed in the middle of broiler house at the height of 40 cm above the back of birds to record audio data at a sampling frequency of 44,100 Hz. A top-view camera was installed to continuously monitor bird activities. Total of 85 min audio data were manually labeled and fed to MATLAB for analysis. The audio data were decomposed using Maximum Overlap Discrete Wavelet Transform (MODWT). Decompositions of the six concerned sound sources were then transformed with the Fast Fourier Transform (FFT) method to generate the single-sided amplitude spectrums. By fitting the amplitude spectrum of each sound source into a Gaussian regression model, its frequency range was determined as the span of the three standard deviations (99% CI) away from the mean. The behavioral frequencies were determined by examining the spectrograms of wing flapping and dustbathing sounds. They were calculated by dividing the number of movements by the time duration of complete behavioral events. The frequency ranges of bird vocalization changed from 2481 ± 191–4409 ± 136 Hz to 1058 ± 123–2501 ± 88 Hz as birds grew. For the sound of fan, the frequency range increased from 129 ± 36–1141 ± 50 Hz to 454 ± 86–1449 ± 75 Hz over the flock. The sound frequencies of feed system, heater, wing flapping and dustbathing varied from 0 Hz to over 18,000 Hz. The behavioral frequencies of wing flapping were continuously decreased from week 3 (17 ± 4 flaps/s) to week 8 (10 ± 1 flaps/s). For dustbathing, the behavioral frequencies decreased from 16 ± 2 scratches/s in week 3 to 11 ± 1 scratches/s in week 6. In conclusion, characterizing sounds of different sound sources in commercial broiler houses provides useful information for further advanced acoustic analysis that may assist farm management in continuous monitoring of animal health and behavior. It should be noted that this study was conducted with one flock in a commercial house. The generalization of the results remains to be explored

    Temperature and Humidity Profiles of Broiler Houses with Experimental Conventional and Tunnel Ventilation Systems

    No full text
    This article describes the spatial and diurnal patterns of air temperature and relative humidity (RH) in commercial-scale broiler houses (12 ¥ 122 m, 40 ¥ 400 ft) using experimental conventional and tunnel heating, cooling, and ventilation systems. The experimental broiler houses used 76-cm (2.5-ft) side curtains and combined mechanical and natural ventilation. Heating was provided by propane brooders and space furnaces. Cooling was accomplished with side-mounted cooling fans and misting nozzles in the conventional houses, but with fans and evaporative cooling pads in the tunnel houses. Interior mixing fans, arranged to circulate air in a “racetrack” fashion, were used in the tunnel houses.This article is from Applied Engineering in Agriculture 10, no. 4 (1994): 535–542.</p
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