Since the broiler industry moved primarily to solid sidewall houses nearly twenty years ago, the goal of providing uniform light intensities by artificial bulbs has been the norm. However, increasing consumer demand for improved bird welfare has led to the provision of natural light via windows in some broiler houses and, consequently, to a more varied lighting environment. The effects of varying window configurations and seasonality on in-house light intensities have not been characterized for windowed houses. This study characterized light intensity using multiple sensor orientations in two Global Animal Partnership (GAP)-certified commercial broiler houses (18.3 × 183.9 m) with different window configurations: one-sided windows (1SW) and two-sided windows (2SW), across summer, winter, and fall flocks. The 1SW configuration included 23 translucent windows on the north sidewall, while the 2SW configuration included windows on both north and south sidewalls, along with two additional west end-wall windows. Two data acquisition units per house measured light intensity at one-minute intervals near bird height in five directions. Data were analyzed across three production phases: brooding (d 1-8), growout1 (d 9-20), and growout2 (d 20-42). Mean light intensity was significantly higher in the 2SW configuration (39.9 lx) compared to the 1SW configuration (27.2 lx) across all seasons and phases. Solar altitude strongly influenced indoor light intensity; mean indoor light intensity in summer (44.4 lx) was only 4% higher than in fall (42.7 lx), despite ambient sunlight being 56% greater in summer. Ceiling-facing sensors captured less than 17% of maximum light ingress, while north- and south-facing sensors captured 60% to 99% suggesting a rotational sweep with a single sensor may better represent the light environment experienced by birds. Relative light uniformity (coefficient of variation) did not statistically differ between window configurations but was better at lower artificial light levels. Overall, these findings demonstrate that window configuration and solar geometry strongly influence the indoor light environment in broiler houses, highlighting the need for improved measurement approaches and more refined design guidelines to ensure consistent and welfare-appropriate lighting conditions.

Monitoring drinking water consumption (WC) is a daily routine for broiler producers and can be a good indicator of flock health and performance. In general, water consumption will increase as broilers age, and any sudden dips or decreasing trend in water consumption can indicate an issue that should be addressed. Due to the lack of information in the literature, this study quantified daily WC trends for broilers grown to nine weeks under commercial conditions. Daily WC was monitored between d 8 to 63 and varied between two flocks. Mean cumulative WC was 14,629 L/1,000 birds, ranging from 13,982 (Flock 2) to 15,276 L/1,000 birds (Flock 1). At wk 8, flocks from this study consumed between 27 to 46% more water on a L/1,000 birds/wk basis than data reported 20 to 30 yrs ago. However, broilers in this study consumed less water to achieve equivalent body weights (BW) when compared to past studies. While reporting broiler WC in units of L/1,000 birds makes discussions in the field easier when trying to estimate the expected water needs of a farm, broiler genetics and husbandry practices continue to increase bird weights earlier in the flock. Including a WC:BW in terms of mL of WC to kg of BW can provide a more accurate comparison. Future WC research studies should include additional data to allow for better comparisons between studies: weekly BW, environmental set-points, in-house air temperature, lighting photoperiod and intensity, diet composition by feeding phase, drinking system, and water line pressures, and others.

Broiler litter management is critical for overall bird health and performance. Poor litter conditions can result in increased ammonia (NH3) volatilization and moisture, which negatively impact bird productivity and welfare. Poultry Litter Treatment (R) (PLT) is a litter amendment that has been applied to reduce ammonia (NH3) volatilization; however, PLT does not address litter moisture content (MC). Biochar (BC) is a porous material with a high surface area that may absorb moisture and mitigate NH3 volatilization. The objectives of this study were to evaluate the effects of BC and PLT on MC, NH3 volatilization, and broiler performance during a 42-day flock grow-out. Birds were reared in 1.52 m x 2.74 m pens containing used litter, feeders, and a drinker line. Water activity, pH, and nutrient content were also evaluated. PLT and BC were surface applied at 0.73 kg center dot m-2 and 30 % (vol/vol). A control of non-amended litter was included. Litter samples were collected at d 0, 17, 29, and 41. NH3 was measured on d 0, 14, 28, and 41. Litter treatment and grow-out time significantly impacted NH3 volatilization and MC. Overall, PLT had the lowest NH3 concentrations. On d 41, BC had the highest NH3 (104 ppm). BCtreated litter had the lowest MC and highest NH3, while PLT-treated litter was lowest in NH3 volatilization. Litter treatment had no effect on bird performance, indicating these amendments did not negatively affect bird performance. BC may promote lower MC; however, further research is needed to understand its effects on NH3 volatilization.

In recent years, there has been a movement driven by consumer demands towards adding windows in broiler houses to allow for natural light during rearing; however, little is currently known about the effects of natural light on bird welfare. The objective of this study was to compare the impact of raising broilers under natural light or artificial light on fear response and welfare parameters. Mixed-sex Ross 708 chicks (N=704) were housed in 16 rooms (44 birds/room), with 8 rooms per light treatment and raised until 56d of age. Chicks were randomly assigned to one of two light treatments: artificial light provided via a 5000K LED (AL), or natural light provided via window and supplemented with 5000k LED (NL). Three fear tests were performed, novel object test (at 14d and 35d), response to observer test (at 14d and 35d), and novel environment test (at 55d). Welfare indicators such as footpad dermatitis, hock burn, gait score, and latency to lie were assessed at 55d of age. Data from the novel object test and the response to observer test were analyzed using Proc Mixed, whereas data from the novel environment test and welfare indicators were analyzed using Proc GLIMMIX (SAS 9.4). Results showed that broilers raised under AL were more reluctant to approach Zone 2 (1-meter radius) of novel object than NL broilers (P=0.03). Birds exposed to NL had a shorter mean latency to approach the novel object (69.9 seconds) compared to those under AL conditions (181.4 seconds; P<0.01). No treatment effects were found on the response to observer test, novel environment test, or welfare parameters except for footpad dermatitis, as bird raised under NL showed lower scores than AL birds (P=0.03). Overall, this study indicates that the provision of NL did not show significant improvement in the fear levels or the welfare measures of leg health on broiler chickens.

Light is one of the major enviro-climatic factors in poultry houses that influences physiology and metabolic processes and impact poultry welfare, health, production and behaviors. This study compared the effects of natural and artificial lighting on selected blood physiological variables of broilers grown to 56 days of age. In each of the two trials, a total of 704 (352 males/352 females) 1-d- old Ross x Ross 708 chicks were obtained from a commercial hatchery on day of hatch. The design structure was a randomized complete block design with two treatments and eight replications per trial. Birds were equally and randomly distributed into 16 environmentally controlled rooms in groups of 44 (22 males/22 females) per room. Thus, each of the two treatments were represented by eight rooms with total of sixteen replicates. Temperature and RH on d 1 were maintained at 90 ± 2.1°F and 50 ± 5%, respectively across all treatments rooms. Temperature was decreased by 4 °F per week until it reached 66 °F at 56 d of age. Feed and water were provided ad libitum. Birds were provided a four phase-feeding program (Starter: 0-14 d, Grower: 15-28 d, Finisher: 29-42 d, and Withdrawal: 43-56 d). Blood samples (3 ml) were collected from the brachial wing vein of 3 males and 3 females birds per room on d 28, 42, and 56 which were then analyzed immediately for whole blood physiological variables. Blood plasma samples were analyzed for T3, T4, and corticosterone concentrations. Results showed that artificial light significantly increased sO2 (P < 0.049), SaO2 (P < 0.031), and decreased RHb (P < 0.044) which may be due to slight difference in body weights, but the changes were all within physiological ranges for this species. In addition, blood glucose and plasma corticosterone concentrations were not affected by treatments, signify a similar level of physiological stress between the two light types. In conclusion, physiological variables examined in this study were unaffected by both natural and artificial lighting. However, birds exposed to artificial lighting had slightly increased body weight in comparison with birds reared under natural lighting, which may have a significant impact in commercial poultry production. USDA Agricultural Research Service. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The measurement of illuminance (light intensity) in commercial broiler houses has typically been performed with photometric meters placed on the floor with the sensor facing the ceiling. This orientation is useful in adjusting light intensity from bulbs but does not have the field of view to account for light intrusion through the tunnel fans that may affect bird activity. The objective of this study was to evaluate the effect of sensor orientation on the measurement of light intensities in commercial broiler houses during tunnel ventilation. Light intensity was measured on a commercial broiler farm with three 18.3 x 182.9 m modern broiler houses in southeast Alabama. Stands were constructed to measure light intensity at bird height in five directions [ceiling, evaporative pad end wall, north side wall, south side wall, fan end wall] at each of 76 measurement locations. Target light intensity was set at 0.2 lx. Directional light intensity measurements were simultaneously taken down the length of each house near solar noon (+/- 1.75 h) with all tunnel fans operating. Descriptive statistics were calculated using PROC FREQ, and graphs were generated with SGPLOT in SAS. The current method of using ceiling-facing photometric sensors to quantify light illuminance trends in broiler houses underestimates the light intensities that birds experience. At the center of the house width near the fans, ceiling-facing sensors captured approximately 15.7% of the maximum light ingress (measured by north-side wall sensors facing the tunnel fans). This study has shown that mapping light intensity in five directions for each location provides an improved understanding of the maximum light intensity the birds may be experiencing compared to the current ceiling-facing sensor or other single orientation method. For the described solid-sidewall broiler houses tested during tunnel ventilation, only 46% of the house length was controlled by the lighting system near company-specified target intensities. Light ingress from operating tunnel fans and the evaporative cooling system increased light intensities above target across 54% of the house length. Important photometric sensor orientations to capture maximum light intensities may vary depending on the measurement location, house design and orientation, tunnel fan size and location, number of fans operating, time of day and season, and specified company target intensities.

Phosphorus (P) and Ammonium Nitrogen (N) are essential nutrients for plants and environmental stability. However, their excess in water causes eutrophication, damaging aquatic ecosystems. While adsorption is a promising solution, finding affordable and efficient adsorbents remains a challenge. In this study, magnesium (Mg), iron (Fe), and Mg/Fe doped biochars (BC) adsorbents were synthesized, and evaluated for adsorption of individual P and N and a P+N mixture from a solution and wastewater from a wastewater treatment plant. Compared to other adsorbents, Mg/BC showed excellent performance in adsorbing phosphorus (P) and ammonium nitrogen (N) from aqueous solutions. It demonstrated a large adsorption capacity of 64.65 mg/g and 62.50 mg/g from individual P and N solutions, and 30.3 mg/g and 27.67 mg/g from the P and N mixture solution, respectively. In addition, Mg/BC efficiently removed P and N from real-life wastewater. In the real wastewater, P and N removal efficiencies reached 88.30% and 59.36%, respectively. Kinetics analysis revealed that the pseudo-second-order model accurately described the adsorption of phosphorus (P) and ammonium nitrogen (N) in all solutions. The adsorbent followed the monolayer-Langmuir isotherm for N ions and the multilayer-Freundlich isotherm for P, indicating efficient adsorption processes. Thermodynamic experiments indicated that the adsorption of P and N was not only feasible but also occurred spontaneously in a natural manner. This study revealed that the strategic modification of biochar plays a crucial role in advancing effective wastewater treatment technologies designed for nutrient removal.

Salinity in estuaries varies naturally due to tides, weather, geomorphology, freshwater flow, climate, and sea level. Before the 1950s, water management in southern Florida focused on diverting freshwater to the ocean to make historic wetlands more amenable to development and to protect human life. However, current water management activities aim to restore wetlands and estuaries while maintaining flood control and drinking water for the human population. Due to anthropogenic alteration, the spatiotemporal variability in salinity within Biscayne Bay, Florida, is a significant concern for ecosystem restoration under the Comprehensive Everglades Restoration Plan (CERP). This study aims to analyze daily seasonal salinity trends within the Bay and quantify the change in salinity per year (salinity slope). Salinity data, collected at 30 stations within the central and southern regions of Biscayne Bay over 16 years (2005-2020), were examined for trends. The nonparametric seasonal Kendall trend test, at a 0.05 significance level, was used for the analysis. Results of the trend analysis show that salinity slopes were consistently positive (indicating increasing salinity over time) in the southern portion of the study area and negative (indicating decreasing salinity over time) in the northern portion of the study area. Throughout the study region, most salinity slopes were positive in the wet season and negative in the dry season. The study results show trends in seasonal salinity, which helps in understanding changes in this region. This study will aid future management efforts within Biscayne Bay.

Highlights During brooding, more than 97% of the floor area of new broiler houses was above target light intensity, however, in aged houses less than 0.2% of the floor area was above the target. During tunnel conditions, less than 6% of the floor area met the target light intensity range (0.18–0.22 lx) for both aged and new houses. All floor areas in the fan section exceeded the target light intensity in both aged and new houses in all the farms due to light intrusion from the tunnel fans. Bulbs need to be periodically replaced to meet minimum target levels during brooding and light dimmer adjustments need to be made to meet light intensity targets during tunnel ventilation. Abstract. 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 the target levels set by companies. Therefore, a field survey of twenty 18.3 × 152.4 m broiler houses on five farms was performed to evaluate in-situ light intensity and uniformity in two house sections during brooding [evaporative pad section (pad) and the middle of the house section (mid)] and three sections during tunnel ventilation [pad, mid, and tunnel exhaust fan section (fan)]. Houses ranged in age from new (never used) to aged (5–8 years old). Light intensity measurements were recorded at 70 locations in each of the house sections (140 per house during brooding; 210 per house during tunnel). For tunnel mode, target light intensity values were categorized into above target (>0.22), within target (0.18–0.22 lx), and below target (<0.18 lx). For brooding mode, target light intensity values were below target (<43 lx) and within target (=43 lx). Geostatistics was used to map and calculate the percentage of floor area above, below, or within target thresholds. During brooding and tunnel conditions, the percent of floor area below target (<43 lx and <0.18 lx, respectively) was higher for aged houses than for new houses in the pad and midsections. All the 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 to 0.22 lx target threshold. 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 a 10% threshold of target intensities. 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. Because brood bulbs have a 100% lumen capacity and are not dimmed, a deep cleaning of the bulbs and periodic replacement are recommended if they are not reaching lighting targets. Periodic checking of light intensity is recommended, especially in older houses. Keywords: Broilers, House age, Light intensity, Spatial variation, Target.

Global Animal Partnership (GAP) is an organization that has created alternative standards for raising commercial broilers, including elevated light intensity and provisions for natural light. The objectives of this study were to compare light intensity levels and spatial uniformity in the following treatments derived from GAP lighting standards: 1) light intensity from natural and artificial sources greater than 50 lx (NL1%+LED), and 2) natural light only provided through an opening equal or greater than 1.0% of total floor area (NL1%). Light intensity was also measured in a house using a traditional LED lighting program (LED) for comparison. Light intensity was spatially measured at a fixed point in time (static) for the NL1%+LED, NL1%, and LED treatments and then temporally measured in three house sections (pad, mid, and fan) over a 24 h period. Overall static mean light intensity was significantly higher (P < 0.05) in the NL1%+LED and NL1% treatments than the LED treatment, and most dissimilar in the mid house section (LED = 2.8 lx, NL1%+LED = 95.4 lx, NL1% = 77.1 lx). Seventy-nine percent and 53% of the floor area in the NL1%+LED and NL1% treatments were above 50 lx, the target light intensity set by GAP. Light uniformity was best in the pad and mid sections of the LED treatment. Temporal testing showed at mid house that light intensity was most influenced by natural light and that daily averages were 23 times higher in the NL1% treatment (NL1% = 46.0 lx; LED = 2.0 lx). GAP derived lighting programs resulted in markedly different lighting environments compared to traditional programs.

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. Therefore, a field survey of electrical grounding systems was performed on 96 commercial broiler houses of varying ages in Mississippi and Alabama. Survey parameters included earth ground resistance (Omega, ohms), house age, and grounding system type (traditional grounding rod or Ufer supplemental ground). 64% of surveyed broiler houses were at or below the National Electrical Code (NFPA 70) recommendation of 25 Omega. 58% of traditionally grounded houses and 74% of Ufer supplemental grounded houses were at or below the 25 Omega ground resistance threshold, respectively. Ufer supple-mental grounding has become a required or preferred method over traditional ground rods in new broiler house construc-tion to improve earth grounding. Producers should have their grounding systems inspected annually with an earth ground resistance meter to mitigate both overvoltage and lightning-induced damage.

The effect of various inclusion rates of pine biochar (PBC), miscanthus biochar (MCB) and starting moisture contents on the water activity (Aw) of broiler litter/biochar mixtures was examined. Suitable models for the resulting moisture sorption isotherms were also evaluated. For poultry mixed with PBC and MBC, higher starting moisture contents led to increased Aw. Aw generally increased at high inclusion rates of PBC and MBC, which may be explained by the porous nature and general hydrophobicity of BC. Of the five models examined, the exponential rise to maximum was considered to be the most useful due to its accuracy at moisture contents similar to those commonly found in commercial poultry houses (10–30 % wet basis). Accuracy of models was determined using R2, mean squared prediction error (MSPE), and mean absolute percent error (MAPE). In general, higher inclusion rates of biochar resulted in less overall prediction accuracy. Results from this paper indicate that several moisture isotherm models can be used to effectively model the relationship between moisture content and Aw in broiler litter and biochar mixtures.

SUMMARY. Escherichia coli (E. coli) is a commensal bacteria found in the gastrointestinal tract of poultry; however, some strains are pathogenic and can cause a wide range of diseases. In addition, some strains of pathogenic E. coli can survive in the litter between flocks, making litter management critical for reducing E. coli-associated infections. Biochar (BC) is a porous, carbonaceous material that may be a beneficial litter amendment to reduce moisture and microbial loads. The objectives of this study were to evaluate the effects of pine BC, miscanthus BC, and Poultry Litter Treatment (PLT) on E. coli, total aerobic bacteria populations, and bacterial communities when added to used broiler litter. Pine and miscanthus BC were mixed into poultry litter at inclusion rates of 5%, 10%, 20%, 25%, and 30% w/w. PLT was surface applied at a rate of 0.73 kg/m2. Baseline E. coli and aerobics were measured after a 48-hr litter incubation period and just prior to adding litter treatments. Escherichia coli and aerobics were enumerated 2 and 7 days after adding treatments. Overall, pine BC at 30% had the lowest E. coli and aerobic counts (5.98 and 6.44 log 10 colony-forming units [CFU]/g, respectively); however, they were not significantly different from the control (P ≤ 0.05). At day 2, 30% pine BC inclusion rate treatment resulted in a significant reduction in E. coli and aerobic bacteria counts compared to the control. Miscanthus BC application did not result in significant reductions in E. coli or aerobic bacteria at days 2 or 7. PLT had the highest E. coli (7.07 log 10 CFU/g) and aerobic counts (7.21 log 10 CFU/g) overall. Bacterial community analysis revealed that the alpha and beta diversity between pine BC- and PLT-treated litter were significantly different. However, neither BC type significantly impacted bacterial diversity when compared to the control. Differences in E. coli and aerobic counts between BC types may be attributed to variations in feedstock physiochemical properties. RESUMEN. Evaluación de los efectos del biocarbón de pino y de miscanto sobre Escherichia coli, bacterias aerobias totales y comunidades bacterianas en la cama comercial de pollos de engorde. Escherichia coli (E. coli) es una bacteria comensal que se encuentra en el tracto gastrointestinal de las aves comerciales; sin embargo, algunas cepas son patógenas y pueden causar una amplia variedad de enfermedades. Además, algunas cepas de E. coli patógena pueden sobrevivir en la cama entre parvadas, lo que hace que el manejo de la cama sea fundamental para reducir las infecciones asociadas con E. coli. El biocarbón (BC) es un material carbonoso poroso que puede ser un aditivo beneficioso en la cama para reducir la humedad y las cargas microbianas. Los objetivos de este estudio fueron evaluar los efectos del biocarbón de pino, de miscanthus y de un producto comercial para el tratamiento de la cama en avicultura (PLT) sobre E. coli, sobre poblaciones de bacterias aeróbicas totales y comunidades bacterianas cuando se agregan a la cama de pollos de engorde usada. Se mezclaron biocarbón de pino y miscanthus en la cama de aves de corral con tasas de inclusión por peso del 5 %, 10 %, 20 %, 25 % y 30 %. Se aplicó el producto PLT en la superficie a razón de 0.73 kg/m2. La E. coli y los aeróbicos de referencia se midieron después de un período de incubación de la cama de 48 horas y justo antes de agregar los tratamientos de la cama. Se enumeraron Escherichia coli y bacterias aeróbicas 2 y 7 días después de agregar los tratamientos. En general, el biocarbón de pino al 30 % tuvo los recuentos más bajos de E. coli y aeróbicos (5.98 y 6.44 log10 unidades formadoras de colonias [UFC]/g, respectivamente); sin embargo, no fueron significativamente diferentes del control (P ≤ 0.05). En el día 2, el tratamiento con una tasa de inclusión de biocarbón de pino al 30 % dio como resultado una reducción significativa en los recuentos de bacterias aeróbicas y E. coli en comparación con el control. La aplicación de biocarbón de miscanto no resultó en reducciones significativas de E. coli o bacterias aeróbicas en los días 2 o 7. El producto PLT tuvo los recuentos más altos de E. coli (7.07 log10 CFU/g) y aeróbicos en general (7.21 log10 CFU/g). El análisis de la comunidad bacteriana reveló que la diversidad alfa y beta entre la cama tratada con biocarbón de pino y producto PLT era significativamente diferente. Sin embargo, ninguno de los tipos de biocarbón afectó significativamente la diversidad bacteriana en comparación con el control. Las diferencias en los recuentos de E. coli y de bacterias aeróbicas entre los tipos de biocarbón pueden atribuirse a variaciones en las propiedades fisicoquímicas de la materia prima.

Responses to shifting consumer preferences and demands for alternative rearing programs have resulted in a re-evaluation of lighting programs by the commercial broiler industry. The objectives of this study were to compare light intensity levels, distribution, and uniformity in curtain-sided broiler houses using 2 lighting program treatments: (1) natural light only (NL) and (2) traditional light-emitting diode (LED). The natural light treatment was created by retrofitting an existing curtain with a translucent one. Combined area through which natural light entered the house equaled 10% of the total floor area. A high-density data acquisition system was used to measure light intensity (505 locations per replication) at a fixed point in time (static). Three house sections (pad, mid-house, and fan) were monitored over a 24 h period (temporal) in August and December 2020. Results from the static testing indicate that light intensities were significantly higher (P < 0.05) in the pad, mid-house, and fan sections of the NL house during both testing events. Mean house section light intensities ranged from 1.8 to 71.6 lx in the LED treatment and 9.2 to 545.1 lx in the NL treatment. During both temporal testing events, light intensity was also significantly higher (P < 0.05) in the pad, mid-house, and fan sections for the NL treatment. Light intensity values were as high as 6,000 lx in the NL treatment, over 600 times higher than levels generally accepted by the industry. This study showed that provision of natural light in broiler houses drastically increases light levels throughout the house and reduces overall spatial uniformity.

Hatching egg disinfection is one method to reduce bacterial loads that can negatively impact chick health. Disinfection via electrostatic spray systems can improve chemical and water-use efficiency, however, the disinfection efficacy of these systems on hatching eggs is unknown. The objectives of this study were to 1) evaluate the disinfection efficacy of Bio-Shield 75, bleach (Clorox), and Virocid on hatching eggs using electrostatic spray, and 2) characterize eggshell microbiome responses to the disinfectants. Hatching egg treatments con-sisted of BioShield 75, Virocid, 150 ppm bleach, water, and a dry control. Bacterial counts (CFUs) were measured 1 and 3 h postdisinfection (20 eggs per sampling time) and treatment reps were pooled for 16S rRNA sequencing analysis. Disinfectant type, sampling time, and their interaction affected eggshell bacteria counts (P <= 0.05). Virocid and BioShield 75, and bleach led to reductions in bacterial contamination by 2.66 (P < 0.0001), 2.09 (P < 0.0001), and 0.48 log(10)CFU/egg (P = 0.125), respectively. Average bacteria count increased after 3 h postdisinfection. Eggshell microbiome analysis indicated disinfectants reduced bacterial diversity, but populations were not different among treatment groups (P <= 0.05). Overall, elec-trostatic application of BioShield 75 and Virocid significantly lowered bacterial loads on broiler hatching eggs when compared to bleach, water, and dry controls. The superior disinfec-tion efficacy of BioShield 75 and Virocid may be attributed to their long residual action, which inhibit bacterial recolonization.

The broiler industry‘s rising adoption of antibiotic-free production requires alternative pathogen control strategies. Biochar is carbonized biomass that has been shown to reduce E. coli in soils and waste water; however, the effect of biochar on E. coli in broiler litter is unknown. The objectives of this study were to evaluate the physicochemical properties of pine and miscanthus biochar and determine their impact on E. coli populations in broiler litter compared to poultry litter treatment (PLT). Biochar specific surface area (SSA), pore volume, and pore diameter were measured via BET analysis and chemical composition was analyzed via ultimate analysis. Baseline E. coli abundance was determined in the broiler litter prior to biochar addition (day 0). Pine and miscanthus biochars were then mixed at inclusion rates of 0, 5, 10, 20, 25, and 30% w/w with litter and PLT was surface applied. Treatments were incubated and E. coli was enumerated at days 2 and 7. Pine biochar had higher SSA, pore volume, and carbon content than miscanthus. E. coli counts in pine biochar inclusion rates of 20, 25, and 30% were lowest overall, however, they were not significantly different than the control (0%). Pine‘s higher pyrolysis temperature likely produced more stable biochar with recalcitrant carbon unavailable for bacterial growth. E. coli abundance was highest in PLT treated litter and counts significantly decreased over time for all treatments. Results from this study indicate that higher pyrolysis temperatures of woody materials create biochar that can reduce E. coli populations in broiler litter.

Crop fill rates are measured as an indirect means of assessing management during the brooding phase. Primary breeder guidelines indicate that 95% of the chicks assessed should present a crop that is full, soft, and rounded after 24 h, which indicates chicks have successfully located feed and water. Crop fill progression has received little attention in the scientific literature and is primarily discussed in trade literature, and thus, the dynamic nature of crop fill progression has not been previously characterized. This study examined the role of 2 market weight stocking density treatments (29.3 kg/m2 and 43.9 kg/m2) on performance and crop fill of broilers grown to 14 d. Crop fill progression was observed at 2, 4, 8, 12, 24, and 48 h after placement and tracked BW of birds that presented empty crops at 24 h; chicks with empty crops were identified to track postplacement BW. Stocking density had no significant effect on bird performance or crop fill. At 24 h, 86% of birds in this study had full, soft, and rounded crops, while only 3% of birds had crops that were devoid of food or water at 24 h. BW for birds with empty crops was significantly lower at 7 d (P = 0.006) but not at 14 d (P = 0.535). The data herein indicate that crop fill rates of 95% or higher at 24 h may be difficult to achieve in typical commercial broiler settings. In addition, assessing crop fill may be a useful tool to diagnose conspicuous management problems during brooding, but it does not appear to be a direct predictor of early performance.

Convolutional neural network (CNN)-based computer vision systems have been increasingly applied in animal farming to improve animal management, but current knowledge, practices, limitations, and solutions of the applications remain to be expanded and explored. The objective of this study is to systematically review applications of CNN-based computer vision systems on animal farming in terms of the five deep learning computer vision tasks: image classification, object detection, semantic/instance segmentation, pose estimation, and tracking. Cattle, sheep/goats, pigs, and poultry were the major farm animal species of concern. In this research, preparations for system development, including camera settings, inclusion of variations for data recordings, choices of graphics processing units, image preprocessing, and data labeling were summarized. CNN architectures were reviewed based on the computer vision tasks in animal farming. Strategies of algorithm development included distribution of development data, data augmentation, hyperparameter tuning, and selection of evaluation metrics. Judgment of model performance and performance based on architectures were discussed. Besides practices in optimizing CNN-based computer vision systems, system applications were also organized based on year, country, animal species, and purposes. Finally, recommendations on future research were provided to develop and improve CNN-based computer vision systems for improved welfare, environment, engineering, genetics, and management of farm animals.

Biochar, wood vinegar, and poultry litter are waste streams that can be utilized as soil amendments and fertilizers. However, poultry litter releases several pollutants through nutrient leaching and carries heavy microbial loads, including potential human pathogens. Improving nutrient retention and reducing microbial load in poultry litter may help protect environmental and human health and improve its value as a soil amendment. The objectives of this study were to determine how blending varying proportions of loblolly pine (Pinus taeda L.) biochar, wood vinegar, and poultry litter affected nutrient profiles and microbial abundance over time. Biochar inclusion rates were 0%, 5%, 10%, and 20%, and wood vinegar was applied at 2% w/w. Samples were taken at Day 0, 57, and 112 to measure nitrogen, phosphorus, potassium, pH, total fungi, and total bacteria. Nutrient levels generally decreased with increasing biochar level; however, biochar inclusion rates of 10% and 20% retained nitrogen and phosphorus and exhibited improved physical properties. Overall, adding wood vinegar decreased nutrient concentrations and showed a biocidal effect for bacteria and fungi. Bacteria and fungi showed different relationships with biochar inclusion rates, with fungi preferring higher biochar inclusion rates and bacteria flourishing at lower biochar inclusion rates.