Porcine Feed Efficiency-Associated Intestinal Microbiota and Physiological Traits: Finding Consistent Cross-Locational Biomarkers for Residual Feed Intake

Publication history: Accepted - 21 May 2019; Published online - 18 June 2019Optimal feed efficiency (FE) in pigs is important for economic and environmental reasons. Previous research identified FE-associated bacterial taxa within the intestinal microbiota of growing pigs. This study investigated whether FE-associated bacteria and selected FE-associated physiological traits were consistent across geographic locations (Republic of Ireland [ROI) [two batches of pigs, ROI1 and ROI2], Northern Ireland [NI], and Austria [AT]), where differences in genetic, dietary, and management factors were minimized. Pigs (n = 369) were ranked, within litter, on divergence in residual feed intake (RFI), and 100 extremes were selected (50 with high RFI and 50 with low RFI) across geographic locations for intestinal microbiota analysis using 165 rRNA amplicon sequencing and examination of FE-associated physiological parameters. Microbial diversity varied by geographic location and intestinal sampling site but not by RFI rank, except in ROI2, where more-feed-efficient pigs had greater ileal and cecal diversity. Although none of the 188 RFI-associated taxonomic differences found were common to all locations/batches, Lentisphaerae, Ruminococcaceae, RF16, Mucispirillum, Methanobrevibacter, and two uncultured genera were more abundant within the fecal or cecal microbiota of low-RFI pigs in two geographic locations and/or in both ROI batches. These are major contributors to carbohydrate metabolism, which was reflected in functional predictions. Fecal volatile fatty acids and salivary cortisol were the only physiological parameters that differed between RFI ranks. Despite controlling genetics, diet specification, dietary phases, and management practices in each rearing environment, the rearing environment, encompassing maternal influence, herd health status, as well as other factors, appears to impact intestinal microbiota more than FE. IMPORTANCE Interest in the role of intestinal microbiota in determining FE in pigs has increased in recent years. However, it is not known if the same FE-associated bacteria are found across different rearing environments. In this study, geographic location and intestinal sampling site had a greater influence on the pig gut microbiome than FE. This presents challenges when aiming to identify consistent reliable microbial biomarkers for FE. Nonetheless, seven FE-associated microbial taxa were common across two geographic locations and/or two batches within one location, and these indicated a potentially "healthier' and metabolically more capable microbiota in more-feed-efficient pigs. These taxa could potentially be employed as biomarkers for FE, although bacterial consortia, rather than individual taxa, may be more likely to predict FE. They may also merit consideration for use as probiotics or could be targeted by dietary means as a strategy for improving FE in pigs in the future.The research leading to these results received funding from the European Union’s Seventh Framework Programme (ECO-FCE project number 311794) for research, technological development, and demonstration independently of any commercial input, financial or otherwise. U.M.M. was funded by the Teagasc Walsh Fellowship program. Gwynneth Halley, who assisted with laboratory work, was funded by a Society for Applied Microbiology Students into Work grant

Apoptosis and porphyrin biosynthesis by a photodynamic chemotherapeutic

$\delta$-Aminolevulinic acid (ALA) causes transformed cells to accumulate protoporphyrin IX (Proto). Subsequent exposure to light in vitro causes intracellular Proto to initiate formation of singlet oxygen molecules, leading to self-destruction. This photo-activated destruction by ALA is enhanced by addition of the tetrapyrrole modulator 1,10-phenanthroline (Oph), by enhancing Proto accumulation. We determined the efficacy and intracellular localization and biosynthesis of Proto, and the role of apoptosis in ALA- and Oph-mediated cell death of transformed cells.Methylcholanthrene-induced sarcoma (Meth-A) solid tumors exhibited a synergistic accumulation of Proto when Oph was used in conjunction with ALA. The use of ALA and Oph-based photo-treatment in mice bearing Meth-A solid tumors resulted in necrosis of tumors in 5 of 6 mice, as determined by both a significant reduction in size and histopathology, with little damage to surrounding normal tissue. Some inflammation of the skin was evident after photo-therapy, due to singlet-oxygen mediated cell death of the tumor.The intracellular localization and pathway of porphyrin biosynthesis in transformed cells was investigated. Proto synthesis occurs in the mitochondria and cytoplasm, but neither the transport of pyrroles and porphyrins, nor the location of all the heme-synthesizing enzymes, have been established. We determined that the conversion of ALA to Coprogen occurs in the cytoplasm of MLA 144 cells. We also show that conversion of Coprogen to Proto by isolated MLA 144 mitochondria is an ATP-dependent process. Transport of Coprogen into mitochondria may involve the mitochondrial peripheral-type benzodiazepine receptor (M-PBR).Survival of WEHI 164 and MLA 144 cells declines significantly after 18 h treatment with ALA and Oph in darkness. Oph and Proto, but not ALA, induce growth arrest. After 3 h of incubation Oph, but not Proto or ALA, induce internucleosomal cleavage of DNA, characteristic of apoptosis, in MLA 144 cells. Apoptosis induction appears to be cell cycle dependent, since cells accumulate in early S phase, with little or no cells in G0/G1 phase, indicative of cell-cycle dependent apoptosis. Oph-induced apoptosis was abrogated (75%) by cycloheximide. These results indicate that Oph induces growth arrest and apoptosis in transformed cells.U of I OnlyETDs are only available to UIUC Users without author permissio

LiteBIRD: lite satellite for the study of B-mode polarization and inflation from cosmic microwave background radiation detection

LiteBIRD is a next generation satellite aiming for the detection of the Cosmic Microwave Background (CMB) B-mode polarization imprinted by the primordial gravitational waves generated in the era of the inflationary universe. The science goal of LiteBIRD is to measure the tensor-to-scaler ratio r with a precision of δr < 10-3♦, offering us a crucial test of the major large-single-field slow-roll inflation models. LiteBIRD is planned to conduct an all sky survey at the sun-earth second Lagrange point (L2) with an angular resolution of about 0.5 degrees to cover the multipole moment range of 2 ≤ ℓ ≤ 200. We use focal plane detector arrays consisting of 2276 superconducting detectors to measure the frequency range from 40 to 400 GHz with the sensitivity of 3.2 μK·arcmin. including the ongoing studies. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only