title: Field scale evaluation of bovine-specific DNA as an indicator of tissue degradation during cattle mortality composting.
abstract: Currently, mortality compost is managed by temperature as extent of tissue degradation is difficult to assess. In the present study, field-scale mortality compost was constructed with composted brain tissue (Brain) and compost adjacent to brain tissue (CAB) sampled over 230 d. Following genomic DNA extraction, bovine-specific mitochondrial DNA (Mt-DNA) and bacterial 16S rDNA fragments were quantified using real-time PCR. Genomic DNA yield of Brain and CAB decreased rapidly (89-98%) and stabilized after 7 d. Compared to d 0, Brain Mt-DNA rapidly decreased (84-91% reduction on d 7). In CAB, Mt-DNA dramatically increased until d 28 (up to 34,500 times) thereafter decreasing by 77-93% on d 112. Quantification of bovine Mt-DNA indicates tissue degradation was initially characterized by rapid decomposition and release of cell contents into surrounding compost matrix followed by further degradation of Mt-DNA by flourishing microorganisms. Consequently, bovine Mt-DNA copies in compost matrix were reliable indicators of tissue degradation.
authors.affiliation: Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Xu
authors.forename: Tim
authors.initials: T
authors.lastname: Reuter
authors.forename: Yongping
authors.initials: Y
authors.lastname: Xu
authors.forename: Yu-Hung
authors.initials: YH
authors.lastname: Hsu
authors.forename: Kim
authors.initials: K
authors.lastname: Stanford
authors.forename: Tim A
authors.initials: TA
authors.lastname: McAllister
mesh_terms: D000818:Animals; D001419:Bacteria / Q000235:genetics*; D001673:Biodegradation, Environmental; D001921:Brain / Q000382:microbiology* / Q000648:ultrastructure; D002102:Cadaver; D002417:Cattle; D004272:DNA, Mitochondrial / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics*; D008855:Microscopy, Electron, Scanning; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal