Disinfective Effects Of Four Disinfectants On The Common Pathogenic Microorganisms In Pig Farm

With the development of pig industry and the continuous improvement of large scale in production, the frequent occurrence of diseases become a serious problem troubling pig farms. Therefore, determination of the role pathogens in time and carring out effective bio-security measures to prevent and control the diseases is very important in large-scale pig farms at present. In addition, disinfection is one of a regular and basic bio-security measure in pig farms. Choose of disinfectant and optimal use-method is a role to ensure disinfective effects. Four common disinfectants and four bacteria such as Escherichia coli, Shigella, Streptococcus Sui, Staphylococcus aureus were chosed to study the optimal usage of those infectants in practice, according to the results of isolation and identification of bacteria in diarrhea piglets of a scale pig farm. And then, the effect of an infectant for killing pseudorabies virus isolate also was researched. The main results were summarized as follows:1. The porcine epidemic diarrhea virus(PEDV) and porcine transmissible gastroenteritis virus(TGEV) were not the pathogens casued piglet diarrhea. A gram-negative bacterium was isolated in the liver of diarrhea piglets and was identified as Escherichia coli by biochemical tests and 16 s rRNA sequence analysis. The isolate was highly sensitive to Cephalosporin antibiotic and moderately sensitive to the Ofloxacin class of antimicrobial agents and not sensitive to Ampicillin, Streptomycin, Piperacillin, etc. This epidemic was controlled by using the higly sensitive antibiotic and complete environmental disinfection.2. The optimal use-methods of four disinfectants on the Escherichia coli, shigella, Staphylococcus aureus and Streptococcus Sui were researched in different conditions.(1) Selection of optimal neutralizer for neutraling those infectantsThe optimal neutralizer of glutaraldehyde-decyl methyl bromide(500 mg/L) is Tween-80(3000 mg/L)+ Lecithin(1000 mg/L); bromide-dimethyl didecyl ammonium hydrocarbons(250 mg/L) is Tween-80(3000 mg/L)+ Lecithin(300 mg/L); potassium hydrogen sulfate(2500 mg/L) is sodium thiosulfate(300 mg/L); sodium hypochlorite(275 mg/L) is sodium thiosulfate(300 mg/L).(2) Optimal conditions of the four disinfectants for killing E.coliPtotein distractor-free of bacteria: the optimal conditions of glutaraldehyde-decyl bromide with 250 mg/L, the bromide-dimethyl didecyl ammonium hydrocarbons( 31.25 mg/L),potassium hydrogen sulfate(312.5 mg/L) and sodium hypochlorite(138 mg/L) to kill the E.coli(1.57×107 cfu)completely were under the temperature of 37℃,25℃,4℃ for 5 min, respectively.With the protein distractor in bacteria:(1)with 3% protein distractor in bacteria. The optimal conditions of glutaraldehyde-decyl bromide with 250 mg/L, bromide-dimethyl didecyl ammonium hydrocarbons(62.5 mg/L),potassium hydrogen sulfate(312.5 mg/L) and sodium hypochlorite(138 mg/L) to kill the E.coli(1.57×107 cfu)completely were under the temperature of 25℃for 10 min, respectively.(2)with 25% protein distractor in bacteria. The optimal conditions of glutaraldehyde-decyl bromide with 1000 mg/L,bromide-dimethyl didecyl ammonium hydrocarbons(125 mg/L),potassium hydrogen sulfate(625 mg/L) and sodium hypochlorite(690 mg/L) to kill the E.coli(1.57×107 cfu)completely were under the temperature of 25℃for 10 min, respectively.(3) Optimal conditions of the four disinfectants for killing Staphylococcus aureus.Ptotein distractor-free of bacteria: the optimal conditions of glutaraldehyde-decyl bromide(125 mg/L), the bromide-dimethyl didecyl ammonium hydrocarbons(31.25 mg/L),potassium hydrogen sulfate(312.5 mg/L) and sodium hypochlorite(138 mg/L)to kill the Staphylococcus aureus( 2.15×107 cfu) completely were under the temperature of 37℃,25℃,4℃ for 5 min, respectively.With the protein distractor in bacteria:(1)with 3% protein distractor in bacteria. The optimal conditions of glutaraldehyde-decyl bromide with125 mg/L, bromide-dimethyl didecyl ammonium hydrocarbons(125 mg/L),potassium hydrogen sulfate(1250 mg/L) and sodium hypochlorite(276 mg/L) to kill the Staphylococcus aureus(2.15×107 cfu)completely were under the temperature of 25℃for 10 min, respectively.(2)with 25% protein distractor in bacteria. The optimal conditions of glutaraldehyde-decyl bromide with 1250 mg/L,bromide-dimethyl didecyl ammonium hydrocarbons(250 mg/L),potassium hydrogen sulfate(2500 mg/L) and sodium hypochlorite(1104 mg/L) to kill the Staphylococcus aureus(2.15×107 cfu)completely were under the temperature of 25℃for 10 min, respectively.(4) Optimal conditions of the four disinfectants for killing shigella.Ptotein distractor-free of bacteria: the optimal conditions of glutaraldehyde-decyl bromide(125 mg/L), the bromide-dimethyl didecyl ammonium hydrocarbons(31.25 mg/L), potassium hydrogen sulfate(312.5 mg/L) and sodium hypochlorite(138 mg/L)to kill the shigella(1.24×107 cfu)completely were under the temperature of 37℃,25℃,4℃ for 5 min, respectively.(5) Optimal conditions of the four disinfectants for killing Streptococcus Sui.Ptotein distractor-free in bacteria: the optimal conditions of glutaraldehyde-decyl bromide(125 mg/L), the bromide-dimethyl didecyl ammonium hydrocarbons(31.25 mg/L),potassium hydrogen sulfate(625 mg/L) and sodium hypochlorite(138 mg/L)to kill the Streptococcus Sui(1.2×107 cfu)completely were under the temperature of 37℃,25℃,4℃ for 5 min, respectively.3. Optimal conditions of the glutaraldehyde-decyl bromide for killing pseudorabies virus(PRV).The optimal neutralizer compound was 3000 mg/L glycine for neutralizing 125 mg/L disinfectant which did not influence the PK15 cells. The optimal disinfection condition of the glutaraldehyde-decyl bromide disinfectant on PRV(10-8.1/0.1 mL) were 125mg/L disinfectant at 25℃ for 30 min.The optiml dosage and conditions of four disinfectants for using in practice is: with 125 mg/L glutaraldehyde-decyl bromide, or 250 mg/L bromide-dimethyl didecyl ammonium hydrocarbons, or 312.5 mg/L potassium hydrogen sulfate or 138 mg/L sodium hypochlorite at 25℃for 10 min.