Evaluation of ATP bioluminescence for rapid determination of cleanliness of livestock trailers after a commercial wash.

Pathogens such as porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome (PRRSV), and E. coli are known to spread by contaminated vehicles and equipment. Pork producers have adopted trailer wash policies where each trailer is washed, disinfected, and dried before it can return to a farm. Cleanliness of livestock trailers after washing is determined by visual inspection rather than any objective method. Adenosine triphosphate (ATP) bioluminescence is used in many industries to provide real-time feedback on surface cleanliness through the detection of ATP from organic sources. That same technology may provide trailer wash facilities a way of objectively characterizing a livestock trailer's suitability to return to a farm after washing. Two ATP luminometers (3M Clean-Trace and Neogen AccuPoint) were used to estimate the correlation between ATP bioluminescence readings and aerobic bacterial plate counts (APCs) from sampled surfaces and to determine locations within a livestock trailer that can accurately estimate surface cleanliness. Five locations in livestock trailers were evaluated. Those locations included the nose access door (NAD), back door flush gate, rear side access door (RSAD), belly flush gate (BFG), and belly side access door (BSAD). There was a positive log-log association between the two luminometers (r = 0.59, P < 0.01). Every log unit increase in one unit, resulted in a 0.42 log increase (P < 0.01) in the other unit. ATP can come from bacteria, yeasts, molds, and manure. There was a poor association (r ≥ 0.10, P ≥ 0.02) between APCs and the ATP luminometers. Still, an increase in relative light units (RLUs) resulted in a corresponding increase in colony-forming units. The greatest area of surface contamination measured by APC was the NAD. RLUs were also greater in the NAD compared to the RSAD, the BFG, and the BSAD (P ≤ 0.01). Because APCs and luminometer RLUs provided similar outcomes, statistical process control charts were developed to determine control limits for RLUs. This provides real-time feedback to trailer wash workers in determining cleanliness outcomes for livestock trailers. These data suggest that ATP bioluminescence can be a reliable method to monitor cleaning effectiveness in livestock trailers. Bioluminescence is a monitoring tool that should be used in conjunction with microbial methods to monitor procedures for cleaning and disinfection.

Comparative genome analysis of commensal segmented filamentous bacteria (SFB) from turkey and murine hosts reveals distinct metabolic features.

BACKGROUND: Segmented filamentous bacteria (SFB) are intestinal commensal microorganisms that have been demonstrated to induce the innate and adaptive immune responses in mouse and rat hosts. SFB are Gram-positive, spore-forming bacteria that fail to grow optimally under in vitro conditions due to unique metabolic requirements. Recently, SFB have been implicated in improved health and growth outcomes in commercial turkey flocks. To assess the nature and variations in SFB of turkeys and how they may differ from mammalian-associated SFB, the genome of turkey-associated SFB was compared with six representative genomes from murine hosts using an in silico approach. RESULTS: The SFB-turkey genome is 1.6 Mb with a G + C content of 26.14% and contains 1,604 coding sequences (CDS). Comparative genome analyses revealed that all the seven SFB strain possesses a common set of metabolic deficiencies and auxotrophies. Specifically, the inability of all the SFB strains to synthesize most of the amino acids, nucleotides and cofactors, emphasizing the importance of metabolite acquisition from the host intestinal environment. Among the seven SFB genomes, the SFB-turkey genome is the largest and contains the highest number of 1,604 predicted CDS. The SFB-turkey genome possesses cellular metabolism genes that are absent in the rodent SFB strains, including catabolic pathways for sucrose, stachyose, raffinose and other complex glycans. Other unique genes associated with SFB-turkey genome is loci for the biosynthesis of biotin, and degradation enzymes to recycle primary bile acids, both of which may play an important role to help turkey associated SFB survive and secure mutualism with its avian host. CONCLUSIONS: Comparative genomic analysis of seven SFB genomes revealed that each strain have a core set of metabolic capabilities and deficiencies that make these bacteria challenging to culture under ex vivo conditions. When compared to the murine-associated strains, turkey-associated SFB serves as a phylogenetic outgroup and a unique member among all the sequenced strains of SFB. This turkey-associated SFB strain is the first reported non-mammalian SFB genome, and highlights the impact of host specificity and the evolution of metabolic capabilities.

Draft Genome Sequence of "Candidatus Arthromitus" UMNCA01, a Suspected Commensal Isolated from the Gut Microbiome of Commercial Turkey.

"Candidatus Arthromitus" UMNCA01 was recovered from ileal samples of commercial turkey poults and may have probiotic capabilities. The complete genome was determined using the Illumina MiSeq and HiSeq sequencing platforms. The complete genome consists of 1,631,326 bp and has a G+C content of 26.14%, 1,540 coding sequences (CDS), and 37 RNA coding genes.

Segmented Filamentous Bacteria - Metabolism Meets Immunity.

Segmented filamentous bacteria (SFB) are a group of host-adapted, commensal organisms that attach to the ileal epithelium of vertebrate and invertebrate hosts. A genetic relative of the genus Clostridium, these morphologically unique bacteria display a replication and differentiation lifecycle initiated by epithelial tissue binding and filamentation. SFB intimately bind to the surface of absorptive intestinal epithelium without inducing an inflammatory response. Rather, their presence impacts the generation of innate and differentiation of acquired immunity, which impact the clearance of extracellular bacterial or fungal pathogens in the gastrointestinal and respiratory tracts. SFB have recently garnered attention due to their role in promoting adaptive and innate immunity in mice and rats through the differentiation and maturation of Th17 cells in the intestinal tract and production of immunoglobulin A (IgA). SFB are the first commensal bacteria identified that impact the maturation and development of Th17 cells in mice. Recently, microbiome studies have revealed the presence of Candidatus Arthromitus (occasionally designated as Candidatus Savagella), a proposed candidate species of SFB, in higher proportions in higher-performing flocks as compared to matched lower-performing flocks, suggesting that SFB may serve to establish a healthy gut and protect commercial turkeys from pathogens resulting in morbidity and decreased performance. In this review we seek to describe the life cycle, host specificity, and genetic capabilities of SFB, such as bacterial metabolism, and how these factors influence the host immunity and microbiome. Although the role of SFB to induce antigen-specific Th17 cells in poultry is unknown, they may play an important role in modulating the immune response in the intestinal tract to promote resistance against some infectious diseases and promote food-safety. This review demonstrates the importance of studying and further characterizing commensal, host-specific bacteria in food-producing animals and their importance to animal health.