Effect of feeding broilers diets differing in susceptible phytate content

Measurements of total phytate phosphorus content of diets may be deceptive as they do not indicate substrate availability for phytase; it may be that measurements of phytate susceptible to phytase effects are a more accurate measure of phosphorus (P) availability to the bird. To verify this hypothesis, an experiment was conducted to compare diets formulated to contain either high or low susceptible phytate, supplemented with either 0 or 500 FTU/kg phytase. Susceptible phytate was determined by exposing the feed samples to conditions that mimicked the average pH of the proximal gastrointestinal tract (pH 4.5) and the optimum temperature for phytase activity (37 °C) and then measuring phytate dissolved. Ross 308 birds (n = 240) were fed one of 4 dietary treatments in a 2 × 2 factorial design; 2 diets with high (8.54 g/kg, 57.90% of total phytate) or low (5.77 g/kg, 46.33% of total phytate) susceptible phytate, containing 0 or 500 FTU/kg phytase. Diets were fed to broilers (12 replicate pens of 5 birds per pen) from d 0 to 28 post hatch. Birds fed diets high in susceptible phytate had greater phytate hydrolysis in the gizzard (P < 0.001), jejunum (P < 0.001) and ileum (P < 0.001) and resulting greater body weight gain (BWG) (P = 0.015) and lower FCR (P = 0.003) than birds fed the low susceptible phytate diets, irrespective of phytase presence. Birds fed the high susceptible diets also had greater P solubility in the gizzard and Ca and P solubility in the jejunum and ileum (P < 0.05) and resulting greater tibia and femur Ca and P (P < 0.05) content than those fed the low susceptible diets. All the susceptible phytate was fully degraded in the tract in the absence of added phytase, suggesting the assay used in this study was able to successfully estimate the amount of total dietary phytate that was susceptible to the effects of phytase when used at standard levels. No interactions were observed between susceptible phytate and phytase on phytate hydrolysis. Hydrolysis of phytate was greater (P < 0.05) in the gizzard of birds fed the diets supplemented with phytase, regardless of the concentration of susceptible phytate in the diet. Phytase supplementation resulted in improved BWG (P < 0.001) and FCR (P = 0.001), increased P solubility (P < 0.001) in the gizzard, Ca and P solubility (P < 0.001) in the jejunum and ileum and Ca and P concentration (P < 0.001) and strength (P < 0.001) in the tibia and femur. Pepsin activity was higher in birds fed the diets supplemented with phytase (P < 0.001) and was greater (P = 0.031) in birds fed the high susceptible phytate diets compared with the low susceptible phytate diets. Findings from this study suggest that there may be a measure more meaningful to animal nutritionists than measurements of total phytate

The Role Social Influence Has On Dormitory Residents\u27 Responses to Fire Alarms

Public response to fire alarms has been a major concern for decades. In particular, college dormitories pose a real threat for a catastrophic event if proper fire protocol is not carried out. Social influences may play a role in the decision dorm residents make when a fire alarm is sounded. More specifically, this research addresses to what degree does an authority figure, like a community advisor (CA), a friend, an unknown resident, or being alone, influence self-reported responses to fire alarms. Significant evidence was found confirming our hypothesis that participants in an alone condition reported being more likely to exit than participants in the presence of others while in their dorm room. In addition, we found that participants did not equally report a CA, a friend, or an unknown resident as having the same influence on their decision to exit or not to exit during an alarm. We found evidence that participants are significantly more likely to believe a dorm fire alarm is false as opposed to real, however we were unable to show a biased informational search via confirmation bias. Finally, two video clips of different fire situations were shown to participants to see if suggestion had an effect on intended behavior. The responses given to a video suggesting a real alarm did not significantly differ to the responses given to a video suggesting a false alarm

The effect of bone choice on quantification of mineralization in broiler chickens up to 6 weeks of age

An experiment was conducted to assess the most appropriate bone type for measuring bone mineralization in male broiler chicks up to 42 d. A total of 72 male broilers were raised in 0.64 m2 pens on a litter floor. The study design included 2 dietary treatments (Control and Low) containing differing levels of total phosphorus (7.8 and 4.4 g/kg for Control and Low diets respectively) and calcium (22.7 and 13.1 g/kg for Control and Low diets respectively) with each fed to 6 replicate pens of 6 birds. Each wk, 6 birds per diet were euthanized and leg bones removed to measure ash percentage. Foot, toe, tibia, and femur ash were compared using the mean of both legs from each bird, via t-tests to separate Control and Low diets. At the end of wk 1, diets could not be separated using any of the bone ash measures. From wk 2 to wk 5, both tibia and foot ash differentiated between the Control and Low diets, and tibia continued to show significant differences between the diets into wk 6. Femur ash did not show any dietary differences until wk 3, but then showed significant differences between the diets until wk 6. Toe ash only differentiated between diets at wk 2, and variation both within and between birds was high, particularly with younger birds. These results suggest that bird age has implications when choosing a bone for assessing possible differences in dietary phosphorus and calcium uptake. Femur ash may be more appropriate for showing differences in broilers aged 6 wk and older. Foot ash provides a comparable alternative to tibia ash in birds aged 2 to 5 wk of age, providing a labor- and time-saving alternative

A global database of methane, nitrous oxide and ammonia emission factors for livestock housing and outdoor storage of manure

Livestock manure management systems can be significant sources of nitrous oxide (N2O) methane (CH4) and ammonia (NH3) emissions. Many studies have been conducted to improve our understanding of the emission processes and to identify influential variables in order to develop mitigation techniques adapted to each manure management step (animal house, outdoor storage, and manure spreading to land). The international project DATAMAN (http://www.dataman.co.nz) aims to develop a global database on greenhouse gases (N2O, CH4) and NH3 emissions from the manure management chain to refine emission factors (EF) for national greenhouse gas (GHG) and NH3 inventories. This paper deals with the housing and outdoor storage components of this database. Relevant information for different animal categories, manure types, livestock buildings, outdoor storage and climatic conditions were collated from published peer reviewed research, conference papers and existing databases published between 1995 and 2021. The storage database contains 654 NH3 EF from 16 countries, 243 CH4 EF from 13 countries and 421 N2O EF from 17 countries. Across all gases, dairy cattle and swine production in temperate climate zones are the most represented animal and climate categories. In the housing database, 2024 EF were collated (63% for NH3, 19.5% for CH4 and 17.5% for N2O). As for the storage database, the number of EF for the tropical climate zone is under-represented with only 8 values included. The DATAMAN database can be used for the refinement of national inventories and better assessment of the cost-effectiveness of a range of mitigation measures

Validation of NH3 observations from AIRS and CrIS against measurements from DISCOVER-AQ and the Magic Valley

Ammonia is one of the most common forms of reactive nitrogen and the primary alkaline gas in the atmosphere. Intended and unintended releases of ammonia into the environment over the last century have significantly altered the natural nitrogen cycle, so that the current emission levels of ammonia are about four times higher than in previous centuries. Ammonia is the dominant base in the atmosphere, and it plays a significant role in the formation of fine particulate matter (PM2.5) which can penetrate deep into the lungs and severely impact the respiratory and circulatory systems. In situ measurement of ammonia remains a challenge as ammonia is easy to detect, but it is hard to measure accurately. The high spatial and temporal variability of ammonia exacerbates the lack of continuous, spatially well sampled data over extensive regions. Satellite data, even though they come with their own uncertainties, provide by virtue of their spatial and temporal density, another option for quantifying ammonia emissions. Our objective was to add to the satellite validation record at the single pixel scale, using aircraft and ground ammonia measurements with satellite retrievals from both the Atmospheric Infrared Sounder (AIRS) and Cross-track Infrared Sounder (CrIS) instruments. The AIRS and CrIS profiles individually have large uncertainties, which are driven by local conditions, most significantly temperature profiles and sub-pixel heterogeneity. However, average biases between satellite and aircraft data, after smoothing errors are accounted for, are below or close to 1 ppbv. Use of ground base measurements for validation clearly demonstrate the importance of having more than a few dozen data points to obtain useful information from space-based retrievals of ammonia. With 464 observations over three years, over a small region, it was possible to obtain a clear picture of the source distribution in the region through the application of a physics based oversampling algorithm

Model for calculating ammonia emission from stored animal liquid manure

National inventories calculate ammonia emission from livestock manure using static emission factors. These do not account for local environmental condition, management practice or variation in manure composition. We present a model that estimates emission from liquid manure per area and time as related to slurry composition, temperature and surface covers. Data was extracted from articles and used to parameterize and validate the model, and the scenario calculations demonstrate the usefulness of the model

National greenhouse gas emissions reduction potential from adopting anaerobic digestion on large-scale dairy farms in the United States

Waste-to-energy systems can provide a functional demonstration of the economic and environmental benefits of circularity, innovation, and reimagining existing systems. This study offers a robust quantification of the greenhouse gas reduction potential of industry-level adoption of anaerobic digestion (AD) technology on large-scale dairy farms in the contiguous United States. National GHG reduction estimates were developed through a robust life cycle modeling framework considering 20 dairy configurations that capture important differences in housing and manure management practices, applicable AD technologies, regional climates, storage cleanout schedules, and methods of land application. Results illustrate the potential for AD adoption to reduce GHG emissions from the dairy industry by 2.90 million metric tonnes (MMT) of CO2-eq per year considering current economic barriers, and as much as 5.17 MMT of CO2-eq per year with economic barriers removed. At the farm level, AD technology may reduce GHG emissions from manure management systems by 55-77% depending on the region. Discussion focuses on regional differences in GHG emissions from manure management strategies and the challenges and opportunities surrounding AD adoption

Using seed recovery methods to determine causes of failed germination in native prairie species

Prairie restorations are expensive and emergence rates as low as ten percent are often observed. This could be because seeds are exposed to dangers from microbial and fungal attack, as well as predation from granivores after planting. Our experiment aimed to determine the post-dispersal seed fates of four native prairie species after they had been planted in the soil and covered with an exclosure to limit vertebrate predation. It was performed in a prairie restoration on the University of Northern Iowa Campus in Cedar Falls, Iowa. I coated five sets of 100 seeds of each species (Elymus canadensis, Oligoneuron rigidum, Eryngium yuccifolium, and Desmodium canadense) with fluorescent Glogerm™ and planted them at a depth of five millimeters in four rows (one row of 100 seeds per species, per exclosure) inside five wire mesh exclosures. After five weeks, seedling emergence data was collected and the top layer of soil from each row was excavated from within the exclosures. Collected soil was examined under a UV lamp and recovered seeds were tested for viability. I hypothesized that a majority of the seeds planted would be recovered, and that most of those recovered would be viable. Seed fates differed among the four species and were identified as emerged in the field, died during emergence, viable, and non-viable. Only 10-27% of the seeds planted were accounted for after the first recovery date and 4-10% after the second, and the majority tested were non-viable. Out of those recovered, 39% emerged as seedlings with D. canadense and E. canadensis demonstrating the highest emergence rates of the four species. It is evident that finding seeds after planting is still an obstacle that must be overcome in order to better understand post-dispersal seed fates