A Model for the Regulation of Lipopolysaccharide Synthesis during Outer Membrane Biogenesis in Escherichia Coli

The role of systems biology in the interpretation and analysis of important biological events is gaining rapid acceptance in a number of biological fields. Here a computational systems approach was applied to investigate the production and regulation of Escherichia coli’s (E. coli) outer membrane. The outer membrane comprises of phospholipids in the inner leaflet, and lipopolysaccharides (LPS) in the outer leaflet. LPS is an endotoxin that elicits a strong immune response from humans and its biosynthesis is in part, regulated via degradation of LpxC and WaaA enzymes by the protease FtsH. Despite a substantial amount of research conducted on LPS synthesis, there is remarkably little information on its regulation. The model of the outer membrane synthesis was completed in two phases; firstly a model of lipid A (representing the LPS pathway) was constructed followed by an integrated pathway model which incorporated fatty acids biosynthesis pathway (representing phospholipid production). The parameters used to construct the model were derived from published datasets where available, and estimated when necessary prior to model fitting. Model validation was carried out using a combination of published datasets alongside subsequent experimental data from this research. Model findings suggested that the FtsH-mediated LpxC degradation signal arises from levels of lipid A disaccharide, the substrate for LpxK. This was subsequently validated experimentally using an lpxK overexpression system. Analysis of the integrated model further refined this mechanism indicating the catalytic activity of LpxK appears to be dependent on the concentration of unsaturated fatty acids. This is biologically important because it assists in maintaining LPS/phospholipids homeostasis. Further crosstalk between the fatty acids and lipid A biosynthetic pathways was revealed by experimental observations that LpxC is additionally regulated by an unidentified protease whose activity is independent of lipid A disaccharide concentration, but could be induced in vitro by palmitic acid. The biological relevance of this acute mechanism is not obvious; however, experiments aimed at causing abrupt damage to the cell wall or membrane (by antimicrobials) suggest that under conditions which directly damage membrane structure, LPS regulation via this unidentified protease may be crucial. Computational analysis into the regulation of WaaA suggested that its proteolytic regulation does not affect the LPS synthetic rate. Subsequent experimental analysis provided evidence that WaaA regulation is aimed at controlling the quality of LPS synthesized by preventing glycosylation of undesirable lipid acceptors. Overexpression of waaA resulted in increased levels of 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) sugar whereas, levels of heptose were not elevated in comparison to non-overexpressed cells. This implies that an uncontrolled production of WaaA does not increase LPS level but rather re-glycosylates lipid A precursors. This is the first time experimental data has been produced attempting to explain the regulation of WaaA. Computation of flux coefficient indicates that LpxC is the rate-limiting step when pathway regulation is ignored, but LpxK becomes the limiting step if feedback regulation is included as it is in vivo. Thus, in contrast to LpxC, LpxK may represent a more appropriate target for novel drug development. Overall, the findings of this work provide novel insights into the complex biogenesis of the E. coli outer membrane

Utilising Convolutional Neural Networks for Pavement Distress Classification and Detection

This paper examines deep learning models for accurate and efficient identification and classification of pavement distresses. In it, a variety of related studies conducted on the topic as well as the various identification and classification methods proposed, such as edge detection, machine learning classification informed by statistical feature extraction, artificial neural networks, and real-time object detection systems, are discussed. The study investigates the effect of image processing techniques such as grayscaling, background subtraction, and image resizing on the performance and generalizability of the models. Using convolutional neural networks (CNN) architectures, this paper proposes a model that correctly classifies images into five pavement distress categories, namely fatigue (or alligator), longitudinal, transverse, patches, and craters, with an accuracy rate of 90.4% and a recall rate of 90.1%. The model is contrasted to a current state-of-the-art model based on the You Only Look Once framework as well as a baseline CNN model to demonstrate the impact of the image processing and architecture building techniques discussed on performance. The findings of this paper contribute to the fields of computer vision and infrastructure monitoring by demonstrating the efficacy of convolutional neural networks (CNNs) in image classification and the viability of using CNNbased models to automate pavement condition monitoring

Crosstalk between the lipopolysaccharide and phospholipid pathways during outer membrane biogenesis in Escherichia coli

The outer membrane of gram-negative bacteria is composed of phospholipids in the inner leaflet and lipopolysaccharides (LPS) in the outer leaflet. LPS is an endotoxin that elicits a strong immune response from humans, and its biosynthesis is in part regulated via degradation of LpxC (EC 3.5.1.108) and WaaA (EC 2.4.99.12/13) enzymes by the protease FtsH (EC 3.4.24.-). Because the synthetic pathways for both molecules are complex, in addition to being produced in strict ratios, we developed a computational model to interrogate the regulatory mechanisms involved. Our model findings indicate that the catalytic activity of LpxK (EC 2.7.1.130) appears to be dependent on the concentration of unsaturated fatty acids. This is biologically important because it assists in maintaining LPS/phospholipids homeostasis. Further crosstalk between the phospholipid and LPS biosynthetic pathways was revealed by experimental observations that LpxC is additionally regulated by an unidentified protease whose activity is independent of lipid A disaccharide concentration (the feedback source for FtsH-mediated LpxC regulation) but could be induced in vitro by palmitic acid. Further experimental analysis provided evidence on the rationale for WaaA regulation. Overexpression of waaA resulted in increased levels of 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) sugar in membrane extracts, whereas Kdo and heptose levels were not elevated in LPS. This implies that uncontrolled production of WaaA does not increase the LPS production rate but rather reglycosylates lipid A precursors. Overall, the findings of this work provide previously unidentified insights into the complex biogenesis of the Escherichia coli outer membrane

A Complete Pathway Model for Lipid A Biosynthesis in Escherichia coli

Lipid A is a highly conserved component of lipopolysaccharide (LPS), itself a major component of the outer membrane of Gram-negative bacteria. Lipid A is essential to cells and elicits a strong immune response from humans and other animals. We developed a quantitative model of the nine enzyme-catalyzed steps ofEscherichia colilipid A biosynthesis, drawing parameters from the experimental literature. This model accounts for biosynthesis regulation, which occurs through regulated degradation of the LpxC and WaaA (also called KdtA) enzymes. The LpxC degradation signal appears to arise from the lipid A disaccharide concentration, which we deduced from prior results, model results, and new LpxK overexpression results. The model agrees reasonably well with many experimental findings, including the lipid A production rate, the behaviors of mutants with defective LpxA enzymes, correlations between LpxC half-lives and cell generation times, and the effects of LpxK overexpression on LpxC concentrations. Its predictions also differ from some experimental results, which suggest modifications to the current understanding of the lipid A pathway, such as the possibility that LpxD can replace LpxA and that there may be metabolic channeling between LpxH and LpxB. The model shows that WaaA regulation may serve to regulate the lipid A production rate when the 3-deoxy-D-manno-oct-2-ulosonic acid (KDO) concentration is low and/or to control the number of KDO residues that get attached to lipid A. Computation of flux control coefficients showed that LpxC is the rate-limiting enzyme if pathway regulation is ignored, but that LpxK is the rate-limiting enzyme if pathway regulation is present, as it is in real cells. Control also shifts to other enzymes if the pathway substrate concentrations are not in excess. Based on these results, we suggest that LpxK may be a much better drug target than LpxC, which has been pursued most often

COOPERATIVE SOCIETY AND EMPLOYEES’ WELFARE

Membership of cooperatives entitles eligible members access to financial resources for capital accumulation, investment and consumption purposes. However, becoming a member of the cooperative comes with the price tag of consistent savings that qualifies such committed members access to certain benefits.the World Bank (2015) reports that about 70% of the population still live in abject poverty, 83.9% of the Nigerian population is still living on less than US $2 per day and the inequality of wealth distribution is 42.9%. Based on this background, there is the tendency to question consumer cooperatives welfare promoting impact. We explore the relationship between and employees’ welfare. A survey research design is adopted in which a Likert 5 constructed questionnaires were administered among the faculty and staff members of the Covenant University Cooperative Society, Ota Ibadan, Oyo State, as a means of data collection.through purposive random sampling. Data collected were analysed using the descriptive and inferen societies cut across people in different age, sex, educational attainment, levels of income and number of households. Majority of the respondents were satisfie cooperative societies in meeting the welfare needs of the members. disbursement by the cooperative societies was also found commendable by members

A model for the proteolytic regulation of LpxC in the lipopolysaccharide pathway of Escherichia coli

Lipopolysaccharide (LPS) is an essential structural component found in Gram-negative bacteria. The molecule is comprised of a highly conserved lipid A and a variable outer core consisting of various sugars. LPS plays important roles in membrane stability in the bacterial cell and is also a potent activator of the human immune system. Despite its obvious importance, little is understood regarding the regulation of the individual enzymes involved or the pathway as a whole. LpxA and LpxC catalyze the first two steps in the LPS pathway. The reaction catalyzed by LpxA possesses a highly unfavourable equilibrium constant with no evidence of coupling to an energetically favourable reaction. In our model the presence of the second enzyme LpxC was sufficient to abate this unfavourable reaction and confirming previous studies suggesting that this reaction is the first committed step in LPS synthesis. It is believed that the protease FtsH regulates LpxC activity via cleavage. It is also suspected that the activity of FtsH is regulated by a metabolite produced by the LPS pathway; however, it is not known which one. In order to investigate these mechanisms, we obtained kinetic parameters from literature and developed estimates for other simulation parameters. Our simulations suggest that under modest increases in LpxC activity, FtsH is able to regulate the rate of product formation. However, under extreme increases in LpxC activities such as over-expression or asymmetrical cell division then FtsH activation may not be sufficient to regulate this first stage of synthesis

Phytogenic effect of garlic (Allium sativum), ginger (Zingiber officinale) and roselle (Hibiscus sabdariffa) on the keeping quality of shredded meat

The qualities of meat during storage are deteriorated by microbial growth, oxidation and enzymatic autolysis. Garlic and ginger are recipes used in meat product preparation as antimicrobial and antioxidant substances. .A total of sixty 6-week old broiler chickens were sacrificed and meat removed from the breast muscle where meat chunks were randomly distributed into six treatments. Treatments comprised of shredded meat prepared with a standard recipe containing ginger and garlic (SR-GaG), standard recipe without ginger and garlic (mGaG), standard recipe with ginger (pGin), standard recipe with roselle (pRos), standard recipe with garlic (pGar) and standard recipe with vitamin E (pvE) replacing ginger and garlic respectively. Data were obtained for Moisture, Crude Protein, CP, Crude Fat, CF, Ash, Thiobarbituric Reactive Substances, TBARS) for 0, 7 and 14days refrigerated (4oC) storage including Total Bacterial Count (TBC), Total Fungi Count (TFC) and Total Coliform Count(TCC) for 7, 14 and 21 days refrigerated storage. Data were subjected to analysis of variance using IBM SPSS version 21.. Reduced (p < 0.05) moisture content was observed in group mGaG followed closely by pGin group over 14 days of storage. Significantly higher (p < 0.05) CP was recorded in pGin and pvE groups. Reduced (p < 0.05) CF was observed in pvE group at 7thday while pRos group showed reduced CF among the phytogenics and through the storage periods. The TBARS of pGin, pRos, and pGar reduced (p <0.05) along storage periods. The TBC, TCC, and TFC significantly reduced for shredded meat (mGaG and pGin) while elevated values were observed for other treatments across the storage periods. Listeria salivarius and Micrococcus varians were isolated in SR-GaG throughout the storage periods. Therefore, single addition of ginger and garlic to recipe of shredded meat is recommended for oxidative stability, improved meat quality and meat preservation

Índices hemato-bioquímicos e população microbiana intestinal de frangos de corte alimentados com dieta suplementada com óleo essencial de Prosopis africana (Mesquita Africana)

The objective of this present study was to investigate the haemato-biochemical indices and intestinal microbial population of broiler chickens fed diets supplemented with Prosopis africana (African mesquite) essential oil (PAEO). A total of 540 one-day old broiler chicks of Ross 302 strain were allotted to six treatments with 6 replicates consisting of 15 birds each in a completely randomized design. Feed and water were given ad libitum, and all necessary management practices were strictly observed throughout the experiment, which lasted for 8 weeks. The birds in treatment 1 (T1) was fed a basal diet with no PAEO, T2 was fed basal diet plus 1.2 g kg-1 Oxytetracycline, T3, T4, T5 and T6 were fed basal diet plus PAEO at 200 mg, 400 mg, 600 mg and 800 mg kg-1 respectively. All haematological parameters and intestinal microbial population were influenced by the dietary treatments (p ˂ 0.05). Total protein, triglycerides, cholesterol and urea were significantly different (p < 0.05) across the dietary treatments and are within the physiological ranges reported for healthy chicken. However, serum tryglycerides, low density lipoprotein, high density lipoprotein, magnesium and chloride ion values were not affected by PAEO (p ˃ 0.05). It was concluded PAEO possess several properties – antioxidant, antimicrobial, hepatoprotective, immune-stimulatory, anti-inflammatory and physiological amongst others all of which are vital for the health enhancing effects in birds. Prosopis africana essential oil can be supplemented up to 800 mg kg-1 in the diets of broiler chickens without causing any deleterious effect on their blood profile.El objetivo del presente estudio fue investigar los índices hemato-bioquímicos y la población microbiana intestinal de pollos de engorde alimentados con dietas suplementadas con aceite esencial de Prosopis africana (mezquite africano) (PAEO). Un total de 540 pollos de engorde de un día de edad de la cepa Ross 302 se asignaron a seis tratamientos con 6 repeticiones de 15 aves cada una en un diseño completamente al azar. El alimento y el agua se administraron ad libitum, y todas las prácticas de manejo necesarias se observaron estrictamente durante todo el experimento, que duró 8 semanas. Las aves del tratamiento 1 (T1) recibieron dieta basal sin PAEO, T2 dieta basal más 1,2 g kg-1 de oxitetraciclina, T3, T4, T5 y T6 recibieron dieta basal más PAEO a 200 mg, 400 mg, 600 mg y 800 mg kg-1 respectivamente. Todos los parámetros hematológicos y la población microbiana intestinal fueron influenciados por los tratamientos dietéticos (p ˂ 0.05). Las proteínas totales, los triglicéridos, el colesterol y la urea fueron significativamente diferentes (p < 0,05) entre los tratamientos dietéticos y se encuentran dentro de los rangos fisiológicos informados para pollos sanos. Sin embargo, los valores de triglicéridos séricos, lipoproteínas de baja densidad, lipoproteínas de alta densidad, magnesio e iones de cloruro no se vieron afectados por PAEO (p ˃ 0,05). Se concluyó que PAEO posee varias propiedades: antioxidante, antimicrobiana, hepatoprotectora, inmunoestimuladora, antiinflamatoria y fisiológica, entre todas las demás, que son vitales para los efectos de mejora de la salud en las aves. El aceite esencial de Prosopis africana se puede complementar hasta en 800 mg kg-1 en las dietas de pollos de engorde sin causar ningún efecto nocivo en su perfil sanguíneo.O objetivo do presente estudo foi investigar os índices hemato-bioquímicos e a população microbiana intestinal de frangos de corte alimentados com dietas suplementadas com óleo essencial de Prosopis africana (Mesquita Africana) (PAEO). Um total de 540 pintos de corte de um dia da linhagem Ross 302 foram distribuídos em seis tratamentos com 6 repetições, consistindo 15 aves cada, em um delineamento inteiramente casualizado. Ração e água foram fornecidas ad libitum, e todas as práticas de manejo necessárias foram rigorosamente observadas durante todo o experimento, que durou 8 semanas. As aves do tratamento 1 (T1) receberam dieta basal sem PAEO, T2 receberam dieta basal mais 1,2 g kg-1 de Oxitetraciclina, T3, T4, T5 e T6 receberam dieta basal mais PAEO a 200 mg, 400 mg, 600 mg e 800 mg kg-1, respectivamente. Todos os parâmetros hematológicos e população microbiana intestinal foram influenciados pelos tratamentos dietéticos (p ˂ 0,05). Proteína total, triglicerídeos, colesterol e uréia foram significativamente diferentes (p < 0,05) entre os tratamentos dietéticos e estão dentro das faixas fisiológicas relatadas para frangos saudáveis. Entretanto, os valores séricos de triglicerídeos, lipoproteína de baixa densidade, lipoproteína de alta densidade, magnésio e íons cloreto não foram afetados pela PAEO (p ˃ 0,05). Concluiu-se que o PAEO possui várias propriedades – antioxidante, antimicrobiana, hepatoprotetora, imunoestimulante, anti-inflamatória e fisiológica, entre outras, todas vitais para os efeitos benéficos à saúde das aves. O óleo essencial de Prosopis africana pode ser suplementado até 800 mg kg-1 na dieta de frangos de corte sem causar qualquer efeito deletério em seu perfil sanguíneo

Age influence on effectiveness of a novel 3-phytase in barley-wheat based diets for pigs from 12 to 108 kg under commercial conditions

[EN] The main objective of this study was to evaluate the influence of pig's age on the effectiveness of a new microbial 3-phytase, produced by Komagataella phaffii, under commercial conditions in barley-wheat based diets. Two experiments were conducted in weaned, growing and finishing pigs; firstly, to determine phytase efficacy on dry matter, organic matter, energy, protein and mineral (phosphorus, P and calcium, Ca) digestibility (n = 48; Experiment 1), and secondly, to evaluate the effect of phytase on growth performance and bone mineralization (n = 312; Experiment 2). In each experiment, three barley-wheat based diets were formulated following the recommendations for each animal age, of which two versions were manufactured, including 0 and 1000 phytase units (FTU)/kg of feed of the new 3-phytase to be tested. Results showed the new phytase had the potential to increase the digestibility of Ca and P (on av. + 0.05 and +0.06, respectively; P < 0.01), especially P digestibility in growing pigs (+0.10; P < 0.001), consequently decreasing P and Ca excretion. Digestible energy (DE) of the diet increased with the addition of phytase in weaned pigs (+0.69 MJ/kg of dry matter (DM); P < 0.001). Dietary inclusion of new 3-phytase enhanced average daily gain from 46 to 94 days of age (+0.07 kg/d; P < 0.05) and decreased feed conversion ratio from 46 to 154 days of age (on av. -0.13; P < 0.05), although no significant effect was observed from 154 to 185 days of age. Addition of the new 3-phytase also promoted bone mineralization, increasing the weight of the bones (+3.99 and +3.64 g of tibia at 95 days and metacarpus at 100 days of age, respectively; P < 0.05) and the ash, Ca and P content in these bones (e.g. + 0.46 and +0.33 g of P in tibia at 95 days and metacarpus at 100 days of age, respectively; P < 0.001). In conclusion, pig age affected the efficacy of a new 3-phytase on P and Ca digestibility both in weaned and growing diets and DE content of the weaned diets, which also resulted in improvements in growth, feed conversion and bone development until 154 days of age. These effects seem to be reduced during the finishing period, although the advantages of the new 3-phytase on bone mineralization were maintained until 185 days of age.We thank the technical staff at the experimental farms of the Research and Technology Animal Centre (CITA-IVIA), the Institute of Animal Science and Technology (Universitat Politècnica de Valencia) and Javier Gómez (Crianzas Campovivo) for expert technical assistance and experimental support.Cambra López, M.; Cerisuelo, A.; Ferrer, P.; Ródenas Martínez, L.; Aligué, R.; Moset, V.; Pascual Amorós, JJ. (2020). Age influence on effectiveness of a novel 3-phytase in barley-wheat based diets for pigs from 12 to 108 kg under commercial conditions. Animal Feed Science and Technology. 267:1-13. https://doi.org/10.1016/j.anifeedsci.2020.114549S113267Adeola, O., & Cowieson, A. J. (2011). BOARD-INVITED REVIEW: Opportunities and challenges in using exogenous enzymes to improve nonruminant animal production. Journal of Animal Science, 89(10), 3189-3218. doi:10.2527/jas.2010-3715Almeida, F. N., Sulabo, R. C., & Stein, H. H. (2013). Effects of a novel bacterial phytase expressed in Aspergillus Oryzae on digestibility of calcium and phosphorus in diets fed to weanling or growing pigs. Journal of Animal Science and Biotechnology, 4(1). doi:10.1186/2049-1891-4-8Arredondo, M. A., Casas, G. A., & Stein, H. H. (2019). Increasing levels of microbial phytase increases the digestibility of energy and minerals in diets fed to pigs. Animal Feed Science and Technology, 248, 27-36. doi:10.1016/j.anifeedsci.2019.01.001Atakora, J. K. A., Moehn, S., Sands, J. S., & Ball, R. O. (2011). Effects of dietary crude protein and phytase–xylanase supplementation of wheat grain based diets on energy metabolism and enteric methane in growing finishing pigs. Animal Feed Science and Technology, 166-167, 422-429. doi:10.1016/j.anifeedsci.2011.04.030Blaabjerg, K., Nørgaard, J. V., & Poulsen, H. D. (2012). Effect of microbial phytase on phosphorus digestibility in non-heat-treated and heat-treated wheat–barley pig diets1. Journal of Animal Science, 90(suppl_4), 206-208. doi:10.2527/jas.53920Brady, S., Callan, J., Cowan, D., McGrane, M., & O’Doherty, J. (2002). Effect of phytase inclusion and calcium/phosphorus ratio on the performance and nutrient retention of grower-finisher pigs fed barley/wheat/soya bean meal-based diets. Journal of the Science of Food and Agriculture, 82(15), 1780-1790. doi:10.1002/jsfa.1262Braña, D. V., Ellis, M., Castañeda, E. O., Sands, J. S., & Baker, D. H. (2006). Effect of a novel phytase on growth performance, bone ash, and mineral digestibility in nursery and grower-finisher pigs. Journal of Animal Science, 84(7), 1839-1849. doi:10.2527/jas.2005-565Dersjant‐Li, Y., Awati, A., Schulze, H., & Partridge, G. (2014). Phytase in non‐ruminant animal nutrition: a critical review on phytase activities in the gastrointestinal tract and influencing factors. Journal of the Science of Food and Agriculture, 95(5), 878-896. doi:10.1002/jsfa.6998Eeckhout, W., & De Paepe, M. (1994). Total phosphorus, phytate-phosphorus and phytase activity in plant feedstuffs. Animal Feed Science and Technology, 47(1-2), 19-29. doi:10.1016/0377-8401(94)90156-2EMIOLA, A., AKINREMI, O., SLOMINSKI, B., & NYACHOTI, C. M. (2009). Nutrient utilization and manure P excretion in growing pigs fed corn-barley-soybean based diets supplemented with microbial phytase. Animal Science Journal, 80(1), 19-26. doi:10.1111/j.1740-0929.2008.00590.xGonzález-Vega, J. C., Walk, C. L., & Stein, H. H. (2015). Effects of microbial phytase on apparent and standardized total tract digestibility of calcium in calcium supplements fed to growing pigs1. Journal of Animal Science, 93(5), 2255-2264. doi:10.2527/jas.2014-8215Harper, A. F., Kornegay, E. T., & Schell, T. C. (1997). Phytase supplementation of low-phosphorus growing-finishing pig diets improves performance, phosphorus digestibility, and bone mineralization and reduces phosphorus excretion. Journal of Animal Science, 75(12), 3174. doi:10.2527/1997.75123174xHaug, W., & Lantzsch, H.-J. (1983). Sensitive method for the rapid determination of phytate in cereals and cereal products. Journal of the Science of Food and Agriculture, 34(12), 1423-1426. doi:10.1002/jsfa.2740341217Heaney, R. P., Abrams, S., Dawson-Hughes, B., Looker, A., Looker, A., Marcus, R., … Weaver, C. (2001). Peak Bone Mass. Osteoporosis International, 11(12), 985-1009. doi:10.1007/s001980070020Jørgensen, B. (1995). Effect of different energy and protein levels on leg weakness and osteochondrosis in pigs. Livestock Production Science, 41(2), 171-181. doi:10.1016/0301-6226(94)00048-cKemme, P. A., Jongbloed, A. W., Mroz, Z., & Beynen, A. C. (1997). The efficacy of Aspergillus niger phytase in rendering phytate phosphorus available for absorption in pigs is influenced by pig physiological status. Journal of Animal Science, 75(8), 2129. doi:10.2527/1997.7582129xKiela, P. R., & Ghishan, F. K. (2016). Physiology of Intestinal Absorption and Secretion. Best Practice & Research Clinical Gastroenterology, 30(2), 145-159. doi:10.1016/j.bpg.2016.02.007Kim, J. C., Simmins, P. H., Mullan, B. P., & Pluske, J. R. (2005). The effect of wheat phosphorus content and supplemental enzymes on digestibility and growth performance of weaner pigs. Animal Feed Science and Technology, 118(1-2), 139-152. doi:10.1016/j.anifeedsci.2004.08.016Koch, M. E., & Mahan, D. C. (1985). Biological Characteristics for Assessing Low Phosphorus Intake in Growing Swine. Journal of Animal Science, 60(3), 699-708. doi:10.2527/jas1985.603699xKonietzny, U., & Greiner, R. (2002). Molecular and catalytic properties of phytate-degrading enzymes (phytases). International Journal of Food Science and Technology, 37(7), 791-812. doi:10.1046/j.1365-2621.2002.00617.xLittell, R. C., Henry, P. R., & Ammerman, C. B. (1998). Statistical analysis of repeated measures data using SAS procedures. Journal of Animal Science, 76(4), 1216. doi:10.2527/1998.7641216xMahan, D. C. (1982). Dietary Calcium and Phosphorus Levels for Weanling Swine. Journal of Animal Science, 54(3), 559-564. doi:10.2527/jas1982.543559xMavromichalis, I., Hancock, J. D., Kim, I. H., Senne, B. W., Kropf, D. H., Kennedy, G. A., … Behnke, K. C. (1999). Effects of omitting vitamin and trace mineral premixes and(or) reducing inorganic phosphorus additions on growth performance, carcass characteristics, and muscle quality in finishing pigs. Journal of Animal Science, 77(10), 2700. doi:10.2527/1999.77102700xMoehn, S., Atakora, J. K. A., Sands, J., & Ball, R. O. (2007). Effect of phytase-xylanase supplementation to wheat-based diets on energy metabolism in growing–finishing pigs fed ad libitum. Livestock Science, 109(1-3), 271-274. doi:10.1016/j.livsci.2007.01.118Oryschak, M. A., Simmins, P. H., & Zijlstra, R. T. (2002). Effect of dietary particle size and carbohydrase and/or phytase supplementation on nitrogen and phosphorus excretion of grower pigs. Canadian Journal of Animal Science, 82(4), 533-540. doi:10.4141/a02-016Peter, C. ., Parr, T. ., Parr, E. ., Webel, D. ., & Baker, D. . (2001). The effects of phytase on growth performance, carcass characteristics, and bone mineralization of late-finishing pigs fed maize–soyabean meal diets containing no supplemental phosphorus, zinc, copper and manganese. Animal Feed Science and Technology, 94(3-4), 199-205. doi:10.1016/s0377-8401(01)00300-5Rodehutscord, M., Faust, M., & Lorenz, H. (1996). Digestibility of phosphorus contained in soybean meal, barley, and different varieties of wheat, without and with supplemental phytase fed to pigs and additivity of digestibility in a wheatsoybean-meal diet. Journal of Animal Physiology and Animal Nutrition, 75(1-5), 40-48. doi:10.1111/j.1439-0396.1996.tb00466.xSelle, P. H., & Ravindran, V. (2008). Phytate-degrading enzymes in pig nutrition. Livestock Science, 113(2-3), 99-122. doi:10.1016/j.livsci.2007.05.014Selle, P. H., Cadogan, D. J., & Bryden, W. L. (2003). Effects of phytase supplementation of phosphorus-adequate, lysine-deficient, wheat-based diets on growth performance of weaner pigs. Australian Journal of Agricultural Research, 54(3), 323. doi:10.1071/ar02121She, Y., Su, Y., Liu, L., Huang, C., Li, J., Li, P., … Piao, X. (2015). Effects of microbial phytase on coefficient of standardized total tract digestibility of phosphorus in growing pigs fed corn and corn co-products, wheat and wheat co-products and oilseed meals. Animal Feed Science and Technology, 208, 132-144. doi:10.1016/j.anifeedsci.2015.07.011Van Soest, P. J., Robertson, J. B., & Lewis, B. A. (1991). Methods for Dietary Fiber, Neutral Detergent Fiber, and Nonstarch Polysaccharides in Relation to Animal Nutrition. Journal of Dairy Science, 74(10), 3583-3597. doi:10.3168/jds.s0022-0302(91)78551-2Varley, P. F., Callan, J. J., & O’Doherty, J. V. (2011). Effect of dietary phosphorus and calcium level and phytase addition on performance, bone parameters, apparent nutrient digestibility, mineral and nitrogen utilization of weaner pigs and the subsequent effect on finisher pig bone parameters. Animal Feed Science and Technology, 165(3-4), 201-209. doi:10.1016/j.anifeedsci.2011.02.017Varley, P. F., Flynn, B., Callan, J. J., & O’Doherty, J. V. (2011). Effect of phytase level in a low phosphorus diet on performance and bone development in weaner pigs and the subsequent effect on finisher pig bone development. 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Lessons from participatory community mapping to inform neglected tropical disease programmes in Nigeria

Background: Participatory research methods promote collaborations between researchers and communities to collectively overcome implementation challenges for sustainable social change. Programmes usually take a top-down approach to addressing such challenges. This study developed and piloted contextualised participatory methods to identify community structures that could improve the equity of medicine administration for neglected tropical diseases (NTDs) in northern and southern Nigeria. Methods: Participants and researchers conducted transect walks and social mapping to understand which community-based structures could be used to maximise accessibility and acceptability of medicines for NTDs. Results: Using visual participatory methods with a diverse set of stakeholders facilitated the identification of new structures within the community that could be used to improve the equity of medicine distribution and access. Available materials such as sticks, stones and leaves were appropriately used by respondents in the rural areas, which increased meaningful engagement irrespective of their literacy level. Structures identified included Qur'anic schools, football grounds, mechanics shops, shrines, village head's houses and worship centres. Challenges in using these structures for medicine distribution included resistance from school authorities and restrictions to women's access due to traditions and norms, particularly within palaces and mosques. Conclusions: This article highlights the importance of meaningful community engagement methods and engaging gatekeepers in visual participatory methods. It emphasizes the importance of including divergent views of various population groups in order to ensure that all communities are reached by NTDs programmes