Research Project: Improving Sustainability and Resiliency in Commercial Broiler Production

Location: Poultry Research

2023 Annual Report

Objectives
1. Develop advanced decision tools for environmental control and production management in commercial poultry environments. 1.A. Characterize control system error in modern poultry house integrated control systems. 1.B. Evaluate effects of varying thermal conditions on behavior of broilers during the heating period. 1.C. Establish baseline metabolic response data for enhanced environment rearing programs for input into advanced environmental control models. 2. Develop management and nutritional response strategies for supply chain disruption in commercial broiler production models. 2.A. Evaluate nutritional and lighting strategies to manage growth trajectory during market disruptions. 2.B. Evaluate extreme weather event frequency and impact on poultry operations and housing design requirements. 2.C. Evaluate extreme weather event frequency and impact on poultry operations and energy and water use projections.

Approach
Existing commercial broiler production systems provide limited decision support tools towards improved sustainability and resiliency. Precision animal management (PAM) methods and associated technologies seek to bridge the gap between animal response and environmental control to supplement conventional husbandry and housing management through data analytics and artificial intelligence. Recent advances in computing, data science, and cloud connectivity will ultimately offer the ability to optimize the production environment and revolutionize animal care. However, poor quality and availability of data, lack of sufficiently accurate mechanistic models, and antiquated design philosophy limit applications of these approaches. Data quality from on-farm automation systems will be used to assess variations from prescribed environmental setpoints and the impact those deviations have on the actual environmental conditions and the resulting animal responses and energy/water resource consumption. Updated estimates of metabolic response to modern production practices and diets will provide improved guidance on facility design and control strategies to reduce environmental stressors and ensure resiliency during adverse weather events. Management and nutritional strategies for growth trajectory control will be developed to assist producers in mitigating losses due to acute market contractions such as those experienced during pandemic conditions. Variability in weather patterns, particularly extreme temperature events and severe weather (thunderstorms, flooding, lightning) and subsequent impact on environmental conditions, energy and water use, and building environmental control capacity will be assessed to provide much needed guidance on facility design. The proposed project seeks to develop accurate and useful tools to enhance sustainability and resiliency in commercial broiler operations.

Progress Report
Research conducted to address Objective 1 is designed to develop advanced decision tools for environmental control and production management in commercial poultry environments. Under Subobjective 1A, instrumentation for Phase 1 experiments to assess control system error in broiler house environmental management systems has been developed and commissioned; field measurements will begin in early FY24. Optical sensing systems to address behavioral measurements in Objective 1B have also been developed and commissioned. Behavioral studies to characterize thermoregulatory behavior in broilers during the heating period will begin in early calendar year ’24. Research conducted to address Objective 2 is designed to develop management and nutritional response strategies for supply chain disruption in commercial broiler production. Objective 2.A.1 is delayed to FY24 due to the ongoing feed mill repair project at PRU. This experiment will be initiated upon completion of the feed mill project. Creation of a risk assessment database using historical weather events sourced from the National Oceanic and Atmospheric Administration (NOAA) and severe weather warnings are sourced from the Iowa Environmental Mesonet (IEM) has been completed. Data from NOAA and IEM has been extracted and organized into the database in a usable format. A spatial reporting tool (Tableau) for visual representation of the historical data with query functionality for easy retrieval and analysis of events is under development. Analysis of these data will be conducted in FY24. THI frequency analysis for poultry species (broilers, layers, turkeys) for Objective 2. Subobjective 2.C. has been completed using weather data from 3000+ locations in the continental U.S.; spatial analysis of these data are ongoing and will be completed mid FY24.

Accomplishments
1. Using spatial modeling to better understand light uniformity in commercial broiler houses with LED lighting. Commercial broiler companies set specific light intensities and photoperiods during different stages of live production to manage bird behavior and growth, and to support health and welfare. However, it is currently unknown how much of the floor area in commercial houses is within target levels set by companies. ARS researcher in Starkville, Mississippi, determined that during brooding and tunnel conditions, percent of floor area below target (< 43 lx and < 0.18, respectively) was higher for aged houses than new houses in the pad and mid sections. All floor area in the fan section was above target due to light intrusion from operating fans. During tunnel ventilation in the new houses, 4.5, 6.0, and 0.0% of the floor area at the pad, center, and fan sections, respectively, were within the 0.18 – 0.22 lx target. However, in the aged houses, only 0.6, 0.7, and 0.0% of the floor area at the pad, center, and fan sections, respectively, were within the target range. This research illustrates that the newer houses did a better job at meeting or exceeding target light intensities and that very little of the floor area in new and aged houses during tunnel ventilation was within target. Lack of light dimmer adjustment to account for lumen depreciation and accumulation of dust on the bulbs in the aged house most likely led to the lower overall light intensities. Therefore, periodic checking of light intensity is recommended, especially in older houses.

2. Spatial analysis of air velocity, temperature and humidity in incubators using simulated eggs. Understanding temperature variations during incubation have been a critical concern for the optimal development of egg embryos. Temperature variation can alter embryonic mortality, egg moisture loss, hatchability, and post-hatch growth. ARS researcher in Starkville, Mississippi, meansured air temperature and humidity using self-contained data loggers fitted to the top of 3D-printed eggs that allowed the measurement of air temperature at the surface of the simulated egg during the first stage of incubation. Each egg tray was fitted with eight iButton-eggs and 82 simulated eggs. Eight incubators were set to 37.5 °C with 60 % RH for three days. Comparisons were made horizontally (left trays vs. right trays) and vertically (levels 1 – 6). Preliminary findings show that without the heat generated from live eggs, the incubator can maintain a 0.2 °C from top to bottom. Results will be reported for air velocities that may affect temperature differences.

3. Effect of late-stage and early-stage incubation temperature variation on embryonic mortality, hatchability, growth performance, and carcass characteristics of broiler chickens. The effects of both early and late-stage incubation temperature variation on broiler chicken growth performance, carcass yield, and incidence and severity of the meat quality defects, Wooden Breast and White Striping have been assessed by ARS researcher in Starkville, Mississippi. Incubating broiler hatching eggs at temperatures either 2 degrees Fahrenheit above or below control temperatures during both early-stage incubation negatively impacted broiler growth as well as carcass meat, including yields but did not impact the incidence or severity of Wooden Breast or White Striping. Sub-optimal (too hot or too cold) incubation temperatures during late-stage incubation negatively impacted broiler body weight gain and breast muscle weights. Interestingly, broilers incubated 2 degrees Fahrenheit below the control temperature during late-stage incubation had the greatest incidence of severe Wooden Breast but did not alter White Striping. These results underscore the economic importance of careful incubator temperature management during broiler egg incubation.

4. Effect of photometric sensor orientation on the measurement of light intensity (illuminance) in commercial broiler houses during tunnel ventilation. The measurement and management of light intensity in commercial broiler houses has typically been performed with photometric sensors or meters placed on the floor or at bird level with the sensor facing the ceiling. This orientation was useful in adjusting light intensity from light bulbs but does not account for light intrusion through the tunnel fans. A commercial broiler farm with four 18.3 x 182.9 m modern broiler houses in south-eastern Alabama was used in this study by ARS researcher in Starkville, Mississippi. A set of light stands were constructed to measure light from five orientations; (front house (evaporative pads), back house (tunnel fans), left wall, right wall, upward (ceiling)) at each measurement location at bird height. Near the tunnel fans, light intensity was highest for the left and right sidewalls (71 and 269 lux max, respectively) and lowest at the ceiling (18 lux max) as light ingress entered the running tunnel fans. The fan facing sensors (Back) measured the highest light intensity up to 78.0 m (42.6% of house length) from the fan end-wall before light from light bulbs began to drive lighting levels. During tunnel ventilation, prescribed light control is being achieved in roughly 57.4% of the house length. This study illustrates that the standard light meter orientation isn’t telling the full story when it comes to what light the birds perceive in commercial houses due to light intrusion from the tunnel fans.

5. Development and validation of a protocol to determine feed spillage from commercial feed pans. Feed constitutes between 70-80% of total costs in commercial poultry production. Factors including feed form and quality, bird age, feeder height and design, can influence the amount of feed being spilled. Currently, there are no means to quantify the impact of feed spillage. Determining feed spillage at the different growth phases of broilers will provide means to increase efficiency, compare commercial feeding systems, and improve our understanding of broiler behavior, age, feeder design and feed form interactions. A protocol to capture feed spillage from commercial feeders was developed and validated by ARS researcher in Starkville, Mississippi. The catch system consisted of a spillage catch pan, a perforated floor, and a secondary screen. Titanium dioxide (TiO2) was included at 2.5% as a non-digestible tracer. Feed recovery from three treatments (no secondary screen (NS), 1/2-in secondary screen (SS), and 3/8-in SS, were within ±10% feed recovery. The NS approach will overestimate feed recovery in live trials because TiO2 will be found in feces. It was found that the ½-in SS treatment was the best approach to recover feed (96.6%) that was free of feces at 14 d.

6. Electrical system safety in broiler houses. Commercial broiler house construction, maintenance, and insurance costs continue to increase with the adoption of advanced housing control equipment that aid in flock management through automation of environmental control and data collection. Proper earth grounding is essential to protect these systems from lightning strikes or other dangerous electrical surges. However, the quality of grounding systems on broiler farms in Mississippi and Alabama is currently unknown. ARS researcher in Starkville, Mississippi, collaborated with researchers at Mississippi State University and Auburn University to conduct a field survey of electrical grounding systems on broiler farms in Mississippi and Alabama. Survey parameters included earth ground resistance (ohms), house age, and grounding system type (traditional grounding rod or Ufer supplemental ground). The group demonstrated that 64% of surveyed broiler houses were at or below the National Electrical Code (NFPA 70) recommendation of 25 ohms. This work supports the recommendation of annual inspections to mitigate both overvoltage and lightning-induced damage.

7. Design methodology for broiler house insulation needs. Thermal stress adversely affects poultry production efficiency, health, and welfare. Poultry house insulation requirements are typically specified based on engineering design air temperatures, which disregards ambient weather effects such as convective heating and cooling, and solar radiation. ARS researcher in Starkville, Mississippi, collaborated with researchers at Mississippi State University and Auburn University to monitor external temperatures of a commercial broiler house to verify the suitability of using sol-air temperature as a design parameter for broiler housing design. The team also used sol-air temperature to simulate the effects of solar radiation on conductive heat gain during warm weather for a modeled broiler house in varying climatic locations using historical meteorological data. Sol-air temperature yielded higher values of calculated heat gains than that of air temperature for both field evaluations and model simulations, and better accounts for diurnal temperature fluctuations and solar radiation than that of air temperature when estimating heat transfer for a broiler house during warm conditions. This work supports that Sol-air temperature can be predicted with historical meteorological data and used as a design parameter when designing heating and ventilation systems and thermal insulation estimates for warm weather. While traditional steady state estimations of heat transfer using ambient air temperature may be useful for winter conditions, insulation requirements derived from their use may not be adequate under summer conditions in modern broiler houses.

Review Publications
Magee, C.L., Olanrewaju, H.A., Campbell, J., Purswell, J.L. 2022. Effect of photoperiod on live performance in broiler chicks from placement to 14-days-of-age. Journal of Applied Poultry Research. 31:100295. https://doi.org/10.1016/j.japr.2022.100295.
Linhoss, J.E., Davis, J.D., Campbell, J.C., Purswell, J.L., Griggs, K.G., Edge, C.M. 2022. Comparison of commercial broiler house lighting programs using LED and natural light: Part 1 – spatial and temporal analysis of light intensity. Journal of Applied Poultry Research. 31:100272. https://doi.org/10.1016/j.japr.2022.100272.
Olanrewaju, H.A., Evans, J.D., Collier, S.D., Purswell, J.L., Branton, S.L. 2023. Age-related effect of high-frequency LED lighting in laying hens on biochemical, enzymatical, and electrolytes variables. Journal of Applied Poultry Research. 32:3. https://doi.org/10.1016/j.japr.2023.100351.
Rowland, M.R., Chesser, G.D., Linhoss, J.E., Davis, J.D., Campbell, J.C., Purswell, J.L. 2023. Field survey of electrical grounding systems on commercial broiler houses in Mississippi and Alabama. Applied Engineering in Agriculture. 39(2):245-249. https://doi.org/10.13031/aea.15501.
Davis, J.D., Arnold, B.D., Smith, C.R., Griggs, K.G., Rueda, M.S., Campbell, J.C., Edge, C.M., Purswell, J.L. 2023. Field survey of trunk line heating gas leaks in commercial broiler houses. Applied Engineering in Agriculture. 39(3):279-283. https://doi.org/10.13031/aea.15470.
Mousstaaid, A., Fatemi, S.A., Levy, A.W., Purswell, J.L., Olanrewaju, H.A., Baughman, B., Mcnulty, K., Gerard, P.D., Peebles, E.D. 2023. Effects of the in ovo administration of L-ascorbic acid on tissue L-ascorbic acid concentrations, systemic inflammation, and tracheal histomorphology of ross 708 broilers subjected to elevated levels of atmospheric ammonia. Poultry. 2:158-173. https://doi.org/10.3390/poultry2020014.
Olanrewaju, H.A., Purswell, J.L., Evans, J.D., Collier, S.D., Branton, S.L. 2023. Age-related effect of high frequency LED lighting in laying hens Part 1: Blood Physiological Variables. Canadian Journal of Animal Science. https://doi.org/10.1139/cjas-2022-0119.
Li, G., Chesser, Jr, G.D., Purswell, J.L., Magee, C.L., Gates, R.S., Xiong, Y. 2022. Design and development of a broiler mortality removal robot. Applied Engineering in Agriculture. 38(6):853-863. https://doi.org/10.13031/aea.15013.