title: [Isolation and identification of thermophilic bacteria for efficient dead-pig composting].
abstract: OBJECTIVE
  To isolate thermophilic bacteria to degrade organic substances of dead-pig.
  
  
  METHODS
  Primary screening was done by using diluted plate count and selective medium, and then enzyme activity was measured for secondary screening. Two thermophilic bacterial strains N-3 and Y-3 were isolated, and could degrade protein and lipids. To test their effect, the isolates were mixed (V: V = 1:1, the number of bacteria was 10(8) CFU/mL) and inoculated in dead-pigs and sawdust composting with different doses (0%, 0.3%, 0.6% and 0.9% of the wet weight of fermentation materials).
  
  
  RESULTS
  Strain N-3 was identified as Bacillus aestuarii and Y-3 as Geobacillus thermodenitrificans, based on their 16S rDNA gene sequences. The composting temperature of the 0.3%, 0.6% and 0.9% inoculation group could reach 60 degrees C and maintain at the high temperature for about 10 d, which is higher than control (P < 0.01). At the end of composting, the dead-pig degradation rate of the (0%, 0.3%, 0.6% and 0.9% inoculation groups were 71.2%, 75.7%, 96.7% and 97.1%, respectively. The groups of 0.6% and 0.9% were significantly higher than the control (P < 0.01).
  
  
  CONCLUSIONS
  Sufficient amount inoculation of thermophilic bacteria (> 0.6%) could effectively increase composting temperature, maintain thermophilic stage for longer time, and accelerate degradation of dead-pig by composting.
authors.forename: Hailong
authors.initials: H
authors.lastname: Li
authors.forename: Lvmu
authors.initials: L
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Qian
authors.forename: Fazhi
authors.initials: F
authors.lastname: Xu
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002102:Cadaver; D005285:Fermentation; D006358:Hot Temperature; D008969:Molecular Sequence Data; D010802:Phylogeny; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D013552:Swine / Q000378:metabolism / Q000382:microbiology*
chemical_list: D012987:Soil