@article{leonard_2024, title={Development of an interdisciplinary undergraduate and graduate course in precision livestock farming systems}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae102.404}, abstractNote={Abstract The modern livestock industry is increasingly adopting data, technologies, and automation into daily husbandry and management routines and decisions. These advances in precision livestock farming (PLF) enable improved financial margins, sustainability, efficiency, and animal productivity and welfare. However, there is currently a gap between the engineers and data scientists designing the technologies and the animal scientists and caretakers using them. At North Carolina State University a novel course on PLF Systems for undergraduate and graduate students was developed in the Department of Animal Science. Through lecture delivery, livestock production scenarios, scientific literature, and data-based homework assignments students explored data collection, management, analysis, and data-based decision making. Students gained hands-on experience with a variety of sensor types and signal processing through lab-based activities. Basic hardware and software development concepts were explored during an Arduino-based microcontroller activity. The course was developed and refined using student feedback to include additional sensor and lab-based days and additional in-class supported activities utilizing Excel for data manipulation, processing, and presentation. Self-reported student learning results were collected across two semesters (19 students; 18 Animal Science, 1 Biological Engineering) with84% of students indicated the course was effective in increasing their ability to evaluate and implement technology in livestock production systems and 74% of students reported increased knowledge of coding and software, as well as their ability to clean, analyze, and make sense of raw data. The topics and delivery methods implemented in this course could inform the basis for development of similar interdisciplinary PLF courses at other academic institutions.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Leonard, Suzanne M.}, year={2024}, month={May} }
@article{bery_brown-brandl_rohrer_sharma_leonard_2024, title={Impacts of crate design, number of heat lamps and lying posture on the occurrence of shoulder lesions in sows}, volume={247}, ISSN={["1537-5129"]}, url={https://doi.org/10.1016/j.biosystemseng.2024.09.017}, DOI={10.1016/j.biosystemseng.2024.09.017}, journal={BIOSYSTEMS ENGINEERING}, author={Bery, Shubham and Brown-Brandl, Tami M. and Rohrer, Gary A. and Sharma, Sudhendu Raj and Leonard, Suzanne M.}, year={2024}, month={Nov}, pages={249–256} }
@article{kittle_leonard_knauer_almond_2024, title={Water quality analysis and flow rate comparison between wean-finish swine barns}, volume={102}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skae102.033}, abstractNote={Abstract Water is an essential nutrient to sustain life and a vital component of biological functioning, impacting regulation of pig body temperature along with transporting nutrients to the body. Drinker availability, position, design, water flow rate and pressure, and water quality are major components of pig water intake. The ideal water flow rate for wean-to-finish pigs is 1 L m-1. Excessive flow rates could limit pig water intake and increase humidity in the barn, while too little water flow can lead to a decrease in water intake and biological functioning of the pig. Water should not contain harmful substances and should be readily accessible to pigs. Compounds in water are highly variable depending on region, water source, and pH. Quality of water influences feed consumption along with pig health. Water can contain a variety of microorganisms such as bacteria, viruses, algae, and protozoa; while not all microorganisms are harmful a highly contaminated water analysis is an index of poor water quality. In this study water quality and water flow rates were analyzed across five wean-finish sites comprising 16 barns for three turns of finishing pigs. Water flow rates were measured twice per turn, wk 1 and wk 17. Each barn contained 36 pens and flow rate measurements were collected in 8 pens evenly distributed within the barn. One suspended water source was available per pen, with two nipple drinkers per water source. Water flow rates were averaged over each turn within barns. Average water flow rates were 1.42 L m-1 with standard deviation of 0.44 L m-1. Overall barn water flow rates ranged from 0.78 to 2.19 L m-1. Barn flow rates were compared over time to evaluate performance and maintenance of facilities. Water quality samples were also collected and submitted for standard water analysis. Results will provide information on management strategies to assess water quality and water flow rates in wean-finish facilities.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Kittle, Olivia C. S. and Leonard, Suzanne M. and Knauer, Mark and Almond, Glen}, year={2024}, month={May}, pages={27–27} }
@article{kittle_leonard_knauer_almond_2023, title={Comparison of Ammonia Concentrations Between Flush and Pull-Plug Waste Management Systems in Wean-Finish Swine Barns.}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad068.139}, abstractNote={Abstract
Pig manure contains a wide variety of corrosion-inducing chemicals such as ammonia. Ammonia production and its release are influenced by temperature and moisture in the barn environment. Increased concentrations of ammonia can negatively affect pig health and growth, as well as pose a risk to human health. Additionally, even at decreased concentrations, ammonia reacts with humidity and causes premature corrosion of barn equipment and is a threat to the structural integrity of livestock buildings. In this study, ammonia concentrations were monitored and compared between two 880 head wean-finish swine facilities with different types of waste management systems. Both facilities had shallow manure pits, one containing a flush system and one containing a pull plug system to remove manure from the barns into the lagoon. Ammonia, dry-bulb air temperature, and relative humidity levels were measured every0 min for an entire wean-finish cycle (approximately 20 weeks). Data will be compared between the facilities to evaluate the impact of the waste management systems on indoor air quality conditions. Potential implications for pig health and growth and facility maintenance will be explored. Results will provide information on best management strategies for swine facilities.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Kittle, J. and Leonard, Suzanne M. and Knauer, Mark and Almond, Glen}, year={2023}, month={May} }
@article{peppmeier_leonard_knauer_2023, title={Effect of Temperature and Humidity on Daily Feeding Behavior in Swine}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad068.010}, abstractNote={Abstract
Heat stress has negative impacts on pork production, particularly during the grow-finish phase. During heat stress events, swine alter feeding behavior to reduce heat production, which can negatively affect performance. Recent technology advancements in feed management systems allow for individualized data recording of feeding behavior for group housed pigs during the finishing phase. The objective of this study was to utilize an RFID-based feed management system to determine feeding behavior patterns of finishing pigs during heat stress conditions and identify changes in behavior due to heat stress events. Data included one pen of 29 Duroc boars reared in a mechanically ventilated facility in north central North Carolina. Feed Intake Recording Equipment (FIRE) pig feeders (n = 3; Osborne Technologies) fed individual pigs in the group housed setting using RFID technology and recorded the number of visits, feed intake of each visit, visit duration, and body weight of each pig during each visit. Feeders were calibrated once per week to ensure accuracy of feed intake and body weight measurements. On day 1 of the study, pigs were placed in the experimental pen and body weights were recorded (37.4 kg ± 4.9 kg) using the FIRE feeders. Air temperature, humidity, and dew point data were collected continuously every 5 minutes from day 13 until the end of the finishing period. Pigs exited finishing (134.5 ± 8.6 kg) on day 83. Feeding behavior traits (number of visits and feed intake) were summarized by day. Temperature, humidity, and heat index were summarized by a maximum, minimum, and mean value for each day. Average temperature, humidity, feeder visits a day, and average daily feed intake across the trial was 26.3 ± 1.6 º C, 75.8 ± 6.7%, 6.1 ± 1.0 visits, 2.66 ± 0.39 kg. Models were used to associate feeding behavior traits with the quadratic effects of day and the linear effects of average temperature and humidity and the interaction of temperature and humidity. Temperature and humidity were associated (P < 0.01) number of feeder visits and average daily intake per day. Further, there was an interaction (P < 0.01) between temperature and humidity in relation to number of feeder visits and average daily feed intake. Results suggest substantial variation in feeding behaviors can be explained by temperature and humidity.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Peppmeier, Zack and Leonard, Suzanne M. and Knauer, Mark}, year={2023}, month={May} }
@article{peppmeier_howard_knauer_leonard_2023, title={Estimating backfat depth, loin depth, and intramuscular fat percentage from ultrasound images in swine}, volume={17}, ISSN={["1751-732X"]}, url={https://doi.org/10.1016/j.animal.2023.100969}, DOI={10.1016/j.animal.2023.100969}, abstractNote={Fast, accurate, and reliable estimates of backfat depth, loin depth, and intramuscular fat percentage in swine breeding stock are used to increase genetic improvement and farm profitability. The objective of this study was to develop an equation-based model for the estimation of swine backfat depth, loin depth, and intramuscular fat percentage estimates obtained from longitudinal ultrasound images. Images were collected from purebred Duroc (n = 230), purebred Large White (n = 154), and commercial (n = 190) pigs born in January 2021 at three farms located in North Carolina. An Exapad ultrasound machine captured longitudinal images across the 10th to 13th ribs at 182 (±12.8 SD) days of pig age. The total number of images processed for Duroc, Large White, and commercial pigs was 1 385, 928, and 1 168 images, respectively. To establish a standard measurement for model comparison, trained personnel following standard company procedures using the BioSoft Toolbox (v4.0.1.2; Biotronics Inc., Ames, IA) obtained backfat and loin depth measurements from the images. Longissimus muscle intramuscular fat percentage was predicted using near-infrared spectroscopy at approximately 22 h postmortem. Backfat and loin depth estimation were conducted only for commercial pigs (n = 190) while intramuscular fat estimation was conducted on all pigs (n = 574). Average backfat depth, loin depth, and intramuscular fat percentage were 14.6 (±2.6 SD) mm, 63.7 (±5.5 SD) mm, and 2.21 (±0.82 SD) %. Image analysis and estimation model development were conducted in MATLAB R2021a. Edge detection via the image gradient was applied to segment ultrasound images into backfat, loin, and rib regions. Segmented images were used to estimate backfat depth, loin depth, and loin intramuscular fat percentage. After image quality control and filtering, the image inclusion rate for each breed-trait combination ranged from 76 to 97%. All Duroc and commercial pigs and 97% of Large White pigs were represented by at least one image for trait estimation. Coefficient of determination of models for the estimation of backfat depth, loin depth, and intramuscular fat percentage were 0.58, 0.57, and 0.56, respectively. Root mean square error of backfat depth, loin depth, and intramuscular fat estimation were 1.65 mm, 3.58 mm, and 0.54%, respectively. Results demonstrate the feasibility of using ultrasound image gradient and an equation-based approach to estimate swine backfat and loin depth, and intramuscular fat percentage. This equation-based approach to estimate carcass traits in live swine can enhance genetic improvement.}, number={10}, journal={ANIMAL}, author={Peppmeier, Z. C. and Howard, J. T. and Knauer, M. T. and Leonard, S. M.}, year={2023}, month={Oct} }
@article{martinez_leonard_heugten_wilcock_rosero_2023, title={Impact of Amount and Solubility of Dietary Fiber Fed During Late Gestation and During the Pre-Farrowing Period on Sow Serum Chemistry and Piglet Vitality Index}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad341.356}, abstractNote={Abstract
This study evaluated the impact of level and solubility of total dietary fiber (TDF) when fed to sows during late gestation and early pre-farrowing on serum chemistry, glucose status and farrowing characteristics. Sows were assigned to a control with no supplement, or a supplement provided once per day at either 0.45 or 0.90 kg. The fiber supplement consisted of either a high soluble dietary fiber (SDF) formulation [9.63% SDF, and 25.25% of insoluble dietary fiber (IDF)] or a high IDF formulation (30.73% IDF and 4.18% SDF). Fiber supplements were formulated using sugar beet pulp and soybean hulls and were provided in addition to a common gestation (12.0% TDF) and lactation diet (11.30% TDF) from day 99 (±1 d) of gestation until parturition. Blood samples were collected from sows on day 110 of gestation immediately before the morning feeding, and 2 and 4 hours after feeding for the analysis of serum chemistry and glucose status, comparing the control and the 0.90 kg SDF and IDF treatments (n = 15 sows). Serological results were within expected ranges. Supplementation with SDF, but not IDF, decreased concentrations of γ-glutamyl transferase (P = 0.003) compared with the control (32.20 vs 39.20 and 44.02 IU/L, respectively) and magnesium tended (P = 0.09) to increase with fiber supplementation. Glucose concentrations measured with a hand-held glucose meter were not affected by time relative to feeding, fiber supplementation, or their interaction (P = 0.94). A pilot study evaluated the impact of the amount of fiber supplemented and the composition of fiber on total duration of fetal expulsion and piglet vitality index (PVI) using video equipment. The PVI scale ranged from 0-3 where 0 = no movement, no breathing; and 3 = good movement, breathing, and able to stand within 1 minute or less. Cameras (n = 12) were placed in the farrowing room the day sows were transferred from gestation (112 ± 1 d). Duration of fetal expulsion ranged from 2.36 to 11.0 hours but was not influenced by fiber supplementation. Partial correlation analysis revealed a negative relationship between the birth interval and PVI (r = -0.24; P = 0.003) and total duration of fetal expulsion and PVI (r = -0.53; P < 0.001), irrespective of treatments. Results suggest that fiber supplementation did not affect serum chemistry and glucose status of sows during late gestation. The pilot study suggested a negative association of duration of fetal expulsion with PVI, but these were not affected by dietary fiber.}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Martinez, Gabriela E. and Leonard, Suzanne and Heugten, Eric and Wilcock, Pete and Rosero, David S.}, year={2023}, month={Oct}, pages={313–314} }
@article{knauer_peppmeier_leonard_2023, title={Sow Location Within Farrowing Room Impacts Reproduction During Heat Stress.}, volume={101}, ISSN={["1525-3163"]}, DOI={10.1093/jas/skad068.013}, abstractNote={Abstract
The objective was to evaluate the impact of sow location, within farrowing room, on reproduction during periods of heat stress. Data were collected on 1,866 sows at a 3,600-sow commercial farm in eastern North Carolina from May to August 2021. In the farrowing buildings, evaporative cool cell pads cooled the air entering the hallway. Cooled air, from the hallway, then entered the farrowing rooms through inlets at the front of the room and was pulled through the room by fans in the back of the farrowing room. For data analysis, each farrowing room was divided into four zones. Zone 1 included the sows at the front of the farrowing room near the inlets letting in cooled air. Zone 4 included sows at the back of the room where air exited the building through fans embedded within the wall. Zones 2 and 3 were intermediate. Each farrowing room on the farm housed between 18 and 36 sows. After farrowing, sows had ad libitum access to the lactation diet. Traits included piglet survival (number weaned ÷ total number born) the percentage of sows conceiving by 7 days after weaning, subsequent total number born, subsequent number born alive, subsequent stillborns, sow caliper score prefarrow, sow caliper score at weaning and sow caliper lactation loss. Results are shown in Table 1. Piglet survival was greater (P < 0.05) for sows that farrowed at the front of the room near the cool air inlets. Similarly, litter weaning weight was heavier (P < 0.05) near the cool air inlets relative to the back part of the farrowing room. The percentage of sows that conceived by 7 days after weaning, and farrowed, was linearly associated (P < 0.05) with farrowing zone. Sows near the cool air inlets lost less (P < 0.05) body condition and farrowed more (P < 0.05) piglets in the subsequent litter relative to sows in the back of the farrowing room. Results showed sows that farrowed at the front of the farrowing room lost less body condition, had greater piglet survival, heavier litter weaning weights and were more likely to be rebred and conceive by 7 days after weaning relative to sows farrowing in the back of the farrowing room.
}, journal={JOURNAL OF ANIMAL SCIENCE}, author={Knauer, Mark and Peppmeier, Zack and Leonard, Suzanne M.}, year={2023}, month={May} }
@article{boston_wang_lin_leonard_kim_mckilligan_fellner_odle_2022, title={Gruel Creep Feeding Accelerates Growth and Alters Intestinal Health of Young Pigs}, volume={12}, ISSN={["2076-2615"]}, url={https://www.mdpi.com/2076-2615/12/18/2408}, DOI={10.3390/ani12182408}, abstractNote={To combat the stress of weaning, we utilized novel gruel creep feeders to supplement suckling pigs with divergent soluble (n = 6 litters) versus insoluble (n = 6) diets compared with un-supplemented controls (n = 6). Post-weaning, pigs were fed a common phase 1 diet. Average daily weight gains of pigs fed soluble and insoluble creep diets were 53% and 17% greater than control pigs, respectively (p < 0.01). Creep intake was higher (82%) for pigs fed the soluble diet, and the accompanying weight increase was sustained post-weaning (p < 0.02). Villus measures were prematurely altered in soluble-creep-fed pigs (p < 0.01), with decreases in villi length, crypt depth, and villus area pre-weaning. No effects of treatment were detected for VFA concentrations and pH in the cecum. There was an interaction between treatment and age for several pro- and anti-inflammatory cytokines (p < 0.01), where soluble-creep-fed pigs had increased cytokine levels with age, whereas cytokine levels in the insoluble and control groups decreased over time. We conclude that a soluble creep diet fed in a gruel state during the pre-weaning period has a positive impact on weaning weight that is sustained post-weaning, and is accompanied by alterations in the intestinal health of young pigs.}, number={18}, journal={ANIMALS}, author={Boston, Timothy E. and Wang, Feng and Lin, Xi and Leonard, Suzanne and Kim, Sung Woo and McKilligan, Denny and Fellner, Vivek and Odle, Jack}, year={2022}, month={Sep} }
@misc{ramirez_hayes_condotta_leonard_2022, title={Impact of housing environment and management on pre-/post-weaning piglet productivity}, volume={100}, ISSN={["1525-3163"]}, url={http://dx.doi.org/10.1093/jas/skac142}, DOI={10.1093/jas/skac142}, abstractNote={AbstractThe complex environment surrounding young pigs reared in intensive housing systems directly influences their productivity and livelihood. Much of the seminal literature utilized housing and husbandry practices that have since drastically evolved through advances in genetic potential, nutrition, health, and technology. This review focuses on the environmental interaction and responses of pigs during the first 8 wk of life, separated into pre-weaning (creep areas) and post-weaning (nursery or wean-finish) phases. Further, a perspective on instrumentation and precision technologies for animal-based (physiological and behavioral) and environmental measures documents current approaches and future possibilities. A warm microclimate for piglets during the early days of life, especially the first 12 h, is critical. While caretaker interventions can mitigate the extent of hypothermia, low birth weight remains a dominant risk factor for mortality. Post-weaning, the thermoregulation capabilities have improved, but subsequent transportation, nutritional, and social stressors enhance the requisite need for a warm, low draft environment with the proper flooring. A better understanding of the individual environmental factors that affect young pigs as well as the creation of comprehensive environment indices or improved, non-contact sensing technology is needed to better evaluate and manage piglet environments. Such enhanced understanding and evaluation of pig–environment interaction could lead to innovative environmental control and husbandry interventions to foster healthy and productive pigs.}, number={6}, journal={JOURNAL OF ANIMAL SCIENCE}, publisher={Oxford University Press (OUP)}, author={Ramirez, Brett C. and Hayes, Morgan D. and Condotta, Isabella C. F. S. and Leonard, Suzanne M.}, year={2022}, month={Jun} }
@inproceedings{peppmeier_knauer_howard_leonard_2021, title={Automating ultrasound measurements of back fat and loin depth in swine}, author={Peppmeier, Z. and Knauer, M. and Howard, J. and Leonard, S.M.}, year={2021} }
@article{leonard_ramirez_2021, title={Effect of stall size, number of heat lamps during farrowing: Part 1}, journal={National Hog Farmer}, author={Leonard, S.M. and Ramirez, B.C.}, year={2021}, month={Aug} }
@article{leonard_ramirez_2021, title={Effect of stall size, number of heat lamps during farrowing: Part 2}, journal={National Hog Farmer}, publisher={National Hog Farmer}, author={Leonard, S.M. and Ramirez, B.C.}, year={2021}, month={Sep} }
@article{leonard_ramirez_2021, title={Effect of stall size, number of heat lamps during farrowing: Part 3}, journal={National Hog Farmer}, publisher={National Hog Farmer}, author={Leonard, S.M. and Ramirez, B.C.}, year={2021}, month={Oct} }
@article{leonard_xin_brown-brandl_ramirez_johnson_dutta_rohrer_2021, title={Effects of farrowing stall layout and number of heat lamps on sow and piglet behavior}, volume={239}, ISSN={0168-1591}, url={http://dx.doi.org/10.1016/j.applanim.2021.105334}, DOI={10.1016/j.applanim.2021.105334}, abstractNote={Farrowing stalls are used in the United States swine industry to reduce pre-weaning piglet mortality, enable efficient individual animal management, and decrease facility construction and operating costs. The quantity and quality of space provided for sows and piglets in farrowing stalls are important economic and welfare considerations. To further explore the impacts of farrowing stall space allocation, a large-scale field study was conducted to compare sow and piglet behavior when housed in three farrowing stall layouts (TSL – traditional stall layout, ECSL – expanded creep area stall layout, ESCSL – expanded sow and creep area stall layout) with either one or two heat lamps (1HL and 2HL, respectively). A computer vision system classified posture budgets and behaviors of 322 sows and piglet location for 324 litters. Linear mixed models were developed to compare behavior and piglet pre-weaning mortality metrics between experimental treatments. Results show sows in ESCSL spent more time lying compared to sows in ECSL (p = 0.028) and less time sitting compared to sows in TSL and ECSL (p < 0.01). Sows with the 2HL treatment had an increase in percentage lying (p = 0.017) and a decrease in percentage standing (p = 0.045) compared to sows with the 1HL treatment. Number of piglets, parity, and batch also influenced sow postural behavior (p < 0.05). Sow lying orientation was not impacted by HL treatment. Sow postures and behaviors were influenced by day of lactation (p < 0.001). Piglets with 2HL treatment spent more time in the heated region and less time in the creep and sow regions for all stall layouts on all days of lactation observed (p < 0.001). In the ESCSL, piglets had a greater percentage of time in the sow region compared to ECSL piglets (p < 0.004). Piglets did not spend equal percentages of time between the two creep or two HL regions (p < 0.001), and piglet location was correlated with sow lying orientation for most of the creep regions analyzed (p < 0.01). Increases in piglet pre-weaning mortality were correlated with increases in sow lying (p = 0.027) and decreases in standing (p = 0.025) and feeding (p < 0.001). However, correlations with sow posture were likely due to the impacts of day of lactation (p < 0.001). No correlations were found between piglet location and pre-weaning mortality (p> 0.05). Results can guide producers to consider wider sow areas in farrowing stalls to better meet sow behavioral needs and to include larger heated areas to meet piglet behavioral needs during lactation.}, journal={Applied Animal Behaviour Science}, publisher={Elsevier BV}, author={Leonard, Suzanne M. and Xin, Hongwei and Brown-Brandl, Tami M. and Ramirez, Brett C. and Johnson, Anna K. and Dutta, Somak and Rohrer, Gary A.}, year={2021}, month={Jun}, pages={105334} }
@article{anderson_leonard_2021, title={Farrowing pen design is focus of precision farming study; Big data enables easier pig behaviour research}, journal={Ontario Farmer}, author={Anderson, F. and Leonard, S.}, year={2021}, month={Jun} }
@article{leonard_xin_ramirez_stinn_dutta_liu_brown-brandl_2021, title={Static and Dynamic Space Usage of Late-Gestation Sows}, volume={64}, ISSN={2151-0040}, url={http://dx.doi.org/10.13031/trans.14002}, DOI={10.13031/trans.14002}, abstractNote={HighlightsA calibration procedure was conducted using a Kinect V2 to convert image pixels to physical measurements.A total of 61 sows were observed, and their static and dynamic space usage was measured from depth images.Equations were developed to predict the length, width, and height of sow space usage.Abstract. The amount of space provided to individually housed sows has both financial and animal welfare implications. Many U.S. swine producers use stall dimensions based on recommendations published in the 1980s (length × width × height: 2.13 m × 0.61 m × 1.00 m). Limited empirical data are available concerning the space allocation needed to accommodate modern sows housed in stalls during breeding, gestation, or farrowing. This study used a time-of-flight depth sensor to quantify static and dynamic space usage of 61 modern sows in late gestation. A calibration equation was developed to convert image pixels to physical dimensions. Statistical models were developed to relate the length, width, and height of sow space usage to body weight. The dimensions of sow space usage were then predicted. Results showed that free choice space usage of average (228 kg) sows was 1.96 m × 1.15 m × 0.93 m (length × width × height). For 95th percentile (267 kg) sows, space usage was 2.04 m × 1.12 m × 0.95 m. The width of space usage was primarily attributed to sow body depth when lying recumbent and the dynamic space used for transitioning between postures. These results help to inform future gestating and farrowing sow housing designs. Further work is needed to understand how restrictions on sow space usage may impact sow welfare and production performance, as well as the space needed to perform behaviors such as defecating, feeding, and turning around. Keywords: Animal welfare, Computer vision, Farrowing stall, Gestation stall, Kinect V2, Space allowance.}, number={1}, journal={Transactions of the ASABE}, publisher={American Society of Agricultural and Biological Engineers (ASABE)}, author={Leonard, Suzanne M. and Xin, Hongwei and Ramirez, Brett C. and Stinn, John P. and Dutta, Somak and Liu, Kai and Brown-Brandl, Tami M}, year={2021}, pages={151–159} }
@misc{leonard_ramirez_weyer_2021, title={Thermal Properties of Concrete Slats During Preheating of Empty Swine Facilities}, url={http://dx.doi.org/10.13031/aim.202100241}, DOI={10.13031/aim.202100241}, abstractNote={Abstract. Providing appropriate thermal conditions for young piglets is critical to growth and welfare, especially during stressful periods after transportation and relocation. When preheating an empty facility prior to the arrival of piglets, raising the air temperature to the desired setpoint can be achieved relatively quickly but heating of other barn components, namely the concrete slat flooring, requires additional time and heat input. In this study, the heat transfer rates to concrete slats in a bench-scale model commercial facility environment were measured under high temperature heating conditions. Temperatures were recorded in multiple locations, including air above the slats, pit head space below the slats, and inside the slats. Results from this study can advise producers on the time and heating input required to preheat facilities prior to piglet arrival to reduce piglet stress and discomfort.}, journal={2021 ASABE Annual International Virtual Meeting, July 12-16, 2021}, publisher={American Society of Agricultural and Biological Engineers}, author={Leonard, Suzanne M and Ramirez, Brett C and Weyer, Sara E}, year={2021} }
@inproceedings{fayne_hodges_leonard_2021, title={Understanding and predicting sow behavior at farrowing}, author={Fayne, B. and Hodges, R. and Leonard, S.M.}, year={2021} }
@article{leonard_xin_brown-brandl_ramirez_dutta_rohrer_2020, title={Effects of Farrowing Stall Layout and Number of Heat Lamps on Sow and Piglet Production Performance}, volume={10}, ISSN={2076-2615}, url={http://dx.doi.org/10.3390/ani10020348}, DOI={10.3390/ani10020348}, abstractNote={Most farrowing facilities in the United States use stalls and heat lamps to improve sow and piglet productivity. This study investigated these factors by comparing production outcomes for three different farrowing stall layouts (traditional, expanded creep area, expanded sow area) and use of one or two heat lamps. Data were collected on 427 sows and their litters over one year. Results showed no statistical differences due to experimental treatment for any of the production metrics recorded, excluding percent stillborn. Parity one sows had fewer piglets born alive (p < 0.001), lower percent mortality (p = 0.001) and over-lay (p = 0.003), and a greater number of piglets weaned (p < 0.001) with lower average daily weight gain (ADG) (p < 0.001) and more uniform litters (p = 0.001) as compared to higher parity sows. Farrowing turn, associated with group/seasonal changes, had a significant impact on most of the production metrics measured. Number of piglets born influenced the percent stillborn (p < 0.001). Adjusted litter size had a significant impact on percent mortality (p < 0.001), percent over-lay (p < 0.001), and number of piglets weaned (p < 0.001). As the number of piglets weaned per litter increased, both piglet ADG and litter uniformity decreased (p < 0.001). This information can be used to guide producers in farrowing facility design.}, number={2}, journal={Animals}, publisher={MDPI AG}, author={Leonard, Suzanne M. and Xin, Hongwei and Brown-Brandl, Tami M. and Ramirez, Brett C. and Dutta, Somak and Rohrer, Gary A.}, year={2020}, month={Feb}, pages={348} }
@inproceedings{leonard_xin_brown-brandl_ramirez_dutta_2020, title={Effects of piglet creep floor area on sow behavior and litter productivity in farrowing stalls}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T. and Ramirez, B.C. and Dutta, S.}, year={2020} }
@inproceedings{ramirez_brown_leonard_weyer_2020, title={Initial phases for conducting high temperature and high humidity depopulation research}, author={Ramirez, B.C. and Brown, J.T. and Leonard, S.M. and Weyer, S.E.}, year={2020} }
@article{leonard_xin_brown-brandl_ramirez_stinn_johnson_liu_2019, title={Characterization of a machine vision system to assess gestating sow space usage}, url={http://dx.doi.org/10.13031/aim.201900782}, DOI={10.13031/aim.201900782}, abstractNote={Physical space allocation for animals is an important consideration when designing animal production facilities. This physical space is defined by the length, width, and height of a volume designated to an individual animal. Animals require static space when stationary, but additional space is needed to perform dynamic postural transitions. Inadequate space to perform basic behaviors and postural adjustments can reduce productivity and welfare. Conversely, excess space introduces inefficiencies, resulting in production losses and unnecessary construction expenses. The most commonly used sow space guidelines were published in the 1980s. Therefore, modern commercial sow’s static and dynamic space requirements must be studied to provide evidence-based guidelines for current producers. Such information can be accurately assessed with the use of time-of-flight depth image sensors. A process to develop calibration equations to convert the depth image pixel measurements into physical dimensions was developed and error was assessed. Sample data collected on structurally sound commercial sows (Landrace × Yorkshire) in late gestation (11-15 weeks) of various parities is described. Length, width, and height of the space utilized by sows were calculated for static positions defined as standing and lateral lying, as well as dynamic sequences defined as standing up and lying down. Results can be used to develop relationships between sow body weight and three dimensional static and dynamic space requirements. This information can be used to inform gestation housing design decisions.}, journal={2019 ASABE Annual International Meeting}, publisher={American Society of Agricultural and Biological Engineers}, author={Leonard, Suzanne M and Xin, Hongwei and Brown-Brandl, Tami M. and Ramirez, Brett C. and Stinn, John P. and Johnson, Anna and Liu, Kai}, year={2019} }
@article{leonard_xin_brown-brandl_ramirez_2019, title={Development and application of an image acquisition system for characterizing sow behaviors in farrowing stalls}, volume={163}, ISSN={0168-1699}, url={http://dx.doi.org/10.1016/j.compag.2019.104866}, DOI={10.1016/j.compag.2019.104866}, abstractNote={Animal behavior can be an indicator of animal productivity and well-being, and thus an indicator of how animals respond to changes in their biophysical environment. This study monitored the behaviors of sows and piglets in a commercial setting utilizing an autonomous machine vision system. The objectives of this research were to: (1) implement a digital and time-of-flight depth imaging system, (2) develop a process with minimal user input to analyze the collected images, and (3) calculate the hourly and daily posture and behavior budgets of sows housed in individual farrowing stalls. Depth sensors were centered above each stall in three farrowing rooms (20 sows per room) and controlled by mini-PCs, acquiring images continuously at 0.2 FPS. Data files were transmitted via Ethernet cable to a switch, then to a 50 TB disk station for storage. Recorded image data were subsequently analyzed to quantify sow posture budgets and behaviors using a computer processing algorithm. Algorithm classifications were compared to those of trained human labelers with sow posture classified correctly >99.2% (sitting: 99.4%, standing: 99.2%, kneeling: 99.7%, lying: 99.9%). Specificity and sensitivity parameters for posture classifications were >84.6%, with the exception of lower specificity for kneeling (20.5%). When lying, direction (sow lying on left or right side of body) was classified with an accuracy of 96.2%. Sows that were not lying were also labeled with a behavior, including feeding (97.0% accuracy), drinking behavior (96.8% accuracy), and other behavior (95.5% accuracy). Each non-lying behavior label had specificity >88.3% and sensitivity >77.4%. This autonomous system enables acquisition of a large amount of replicated data to evaluate the effects of changing the farrowing environment on sow behavior and potentially well-being.}, journal={Computers and Electronics in Agriculture}, publisher={Elsevier BV}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T.M. and Ramirez, B.C.}, year={2019}, month={Aug}, pages={104866} }
@inproceedings{leonard_xin_brown-brandl_ramirez_dutta_2019, title={Effects of one or two heat lamps on sow behavior and piglet performance in farrowing stalls}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T. and Ramirez, B.C. and Dutta, S.}, year={2019} }
@article{leonard_smith_ramirez_2019, title={Emerging technologies for monitoring sow health and welfare}, journal={National Hog Farmer}, author={Leonard, S.M. and Smith, B.C. and Ramirez, B.C.}, year={2019}, month={Aug} }
@article{hess_leonard_2019, title={If one heat lamp is good, is two better?}, journal={National Hog Farmer}, author={Hess, A. and Leonard, S.M.}, year={2019}, month={Nov} }
@inproceedings{leonard_xin_brown-brandl_ramirez_stinn_johnson_2019, title={Implication of modern sow’s static and dynamic space usage on gestation stall design}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T. and Ramirez, B.C. and Stinn, J.P. and Johnson, A.K.}, year={2019} }
@article{leonard_xin_brown-brandl_ramirez_2018, title={An Image Acquisition System for Studying Behaviors of Sows and Piglets in Farrowing Barns}, url={http://dx.doi.org/10.13031/iles.18-018}, DOI={10.13031/iles.18-018}, abstractNote={Behavior studies in commercial swine farrowing room environments often need to monitor each set of sow and piglets individually and simultaneously. Autonomous computer imaging systems can overcome this challenge. The system presented here utilizes a time of flight depth sensor and a digital camera to capture depth and digital images of each sow and litter, housed in individual farrowing stalls. Depth sensors were centered above the stalls on a triangular truss spanning the length of the farrowing room and mounted in waterproof boxes with attached lids, enabling them to easily be waterproofed when cleaning the farrowing room. Each depth sensor was controlled by a mini-PC housed in a waterproof box located on the wall behind the sow for protection of the electronics. Each box also contained a small display monitor for operator ease of access. Images were acquired continuously at 0.2 fps. Data files were transmitted via Ethernet cable to a switch, then to a disk station for storage. This system was implemented in three farrowing rooms, with each room housing 20 sows. Recorded image data were subsequently analyzed to quantify behaviors of the sows and piglets (future work) as affected by dimensions and layout of the farrowing stalls.}, journal={10th International Livestock Environment Symposium (ILES X)}, publisher={American Society of Agricultural and Biological Engineers}, author={Leonard, Suzanne M. and Xin, Hongwei and Brown-Brandl, Tami and Ramirez, Brett C.}, year={2018} }
@inproceedings{leonard_xin_brown-brandl_ramirez_2018, title={An image acquisition system for studying behaviors of sows and piglets in farrowing barns}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85075907421&partnerID=MN8TOARS}, DOI={10.13031/iles.ILES18-018}, booktitle={10th International Livestock Environment Symposium, ILES 2018}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T. and Ramirez, B.C.}, year={2018} }
@misc{wang_li_leonard_shi_xin_chai_li_2018, title={Spatial and Diurnal Variations of Particulate Matter Concentration of a Pilot-Scale Aviary Layer House in Winter}, url={http://dx.doi.org/10.13031/iles.18-141}, DOI={10.13031/iles.18-141}, abstractNote={Abstract. Laying hen production plays an important role in particulate matter (PM) emissions which potentially cause air pollution and adverse health effect on animals and workers. Aviary cage-free (CF) egg production systems have been attracting increasing attention due to concerns over animal welfare and increased market demand. While studies have been conducted to characterize PM concentrations and emissions of aviary CF houses with litter floor, few reports are available of this information for aviary CF layer houses equipped with slat floor. In this study, PM concentrations â both spatial and diurnal patters inside a pilot-scale aviary CF layer house (1,800 laying hens, LxWxH of 28.2 x 9.0 x 3.0 m) in northern China were measured under winter conditions. Daily mean PM2.5, PM10, and TSP levels were found to be 0.19±0.11, 1.05±0.65, 2.90±2.07 mg/m3, respectively, which were considerably lower than those reported in previous studies of aviary CF houses with litter floor in cold weather. Daytime PM concentrations were significantly higher than those at night primarily due to differences in animal activity and feed supply. The average PM10 and TSP concentrations during light period (5:00-21:00 h) were 1.34 mg/m3 and 3.75 mg/m3, amounting to 279% and 304% of those during the dark period (21:00-5:00h), respectively. Spatial variations for PM10 and TSP were observed in the experimental hen house due to non-uniform distribution of ventilation air and localized generation of the constituents. Higher TSP concentrations (4.26 mg/m3) were found at worker respiratory level (2.0 m) as compared to floor level (0.5 m, 3.00 mg/m3). TSP concentration at one end of the house (west) was found to be 28.3% and 86.9% higher than the middle and the opposite (east) end. This spatial variation characteristic points out the importance of multi-location sampling when assessing indoor air quality and aerial emissions (for cross ventilation). Data from this study will be useful for future improvement of the housing ventilation design and operation. Future study should also assess PM concentrations of the housing style under warm seasons.}, journal={10th International Livestock Environment Symposium (ILES X)}, publisher={American Society of Agricultural and Biological Engineers}, author={Wang, Yu and Li, Dapeng and Leonard, Suzanne M and Shi, Zhengxiang and Xin, Hongwei and Chai, Lilong and Li, Baoming}, year={2018} }
@inproceedings{wang_li_leonard_shi_xin_chai_li_2018, title={Spatial and diurnal variations of particulate matter concentration of a pilot-scale aviary layer house in winter}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85075889067&partnerID=MN8TOARS}, DOI={10.13031/iles.ILES18-141}, booktitle={10th International Livestock Environment Symposium, ILES 2018}, author={Wang, Y. and Li, D. and Leonard, S. and Shi, Z. and Xin, H. and Chai, L. and Li, B.}, year={2018} }
@inproceedings{leonard_xin_brown-brandl_stinn_johnson_liu_2017, title={Quantification of static and dynamic spaces for sows}, author={Leonard, S.M. and Xin, H. and Brown-Brandl, T. and Stinn, J. and Johnson, A. and Liu, K.}, year={2017} }