Bio-bedding with automatically running plough system under slatted floor improving air quality of duck house and duck production performances

Abstract: With the development of intensive and scalable breeding of meat-type duck in China, a lot of duck manures have not been processed timely because of traditional extensive duck production system, and become the source of environmental pollution influencing duck health. To mitigate the detrimental effects of feces and fecal pathogenic bacteria on duck health and production performance, a novel duck production system of incorporating bio-bedding under slatted floor (BBSF) was developed. Successful operation of the BBSF system was aided by an automatically running plough system (ARPS) that covered duck feces into the bio-bedding. ARPS was composed of sliding touch wire, limit switches, movement orbit, plowing and harrowing device, connection orbit, transfer vehicle, electric brush, power switches, and transfer orbit. The plowing and harrowing device could run among different duck houses to plow bio-bed by cooperating with connection orbit, transfer orbit, and transfer vehicle. The effects of BBSF on airborne pathogenic bacteria and duck production performances in duck house were investigated, which were in comparison with those by conventional floor bio-bedding (CFBB). A total of 2400 8-day-old ducks were randomly and equally allocated into 2 duck production systems, i.e. BBSF and CFBB. Each production system was divided into 6 pens where the ducks were pre-fed for 7 d. Before the age of 26 days, the bio-bedding was not plowed. During the age of 27-34 and 35-39 days, the bio-bedding was plowed once every 4 days and a day, respectively. The counts of total airborne bacteria, Escherichia coli, Staphylococcus aureu and "Salmonella + Shigella" were tested on the age of 26, 34 and 39 days, respectively. Live weight, ratio of feed to meat, total mortality, and stage mortality were analyzed during experiment period, and market elimination rate was counted at the time of live duck slaughter. The results demonstrated that: 1) The sharing of the plowing and harrowing device by different bio-beddings could be achieved through the ARPS. 2) BBSF significantly increased the amounts of total airborne aerobe (1.531×105 CFU/m3) and Escherichia coli (1.298×104 CFU/m3) at the age of 26 days in duck house (P<0.05), significantly decreased the amounts of total airborne aerobe (2.304×105 CFU/m3) and Staphylococcus aureu (1.353×105 CFU/m3) at the age of 34-days (P<0.05), and significantly decreased the amounts of total airborne aerobe (1.255×105 CFU/m3) and "Salmonella + Shigella" (14.13 CFU/m3) at the age of 39 days (P<0.05). 3) Compared with plowing the bio-bedding once every 4 days, plowing of CFBB once every day decreased the amounts (P<0.05) of total airborne bacteria (2.688×105 CFU/m3), Escherichia coli (2.038×104 CFU/m3), Staphylococcus aureu (8.900×104 CFU/m3) and "Salmonella + Shigella" (47.11 CFU/m3), however, the amounts of total airborne aerobe (1.255×105 CFU/m3) and "Salmonella + Shigella" (14.13 CFU/m3) in BBSF were decreased (P<0.05). 4) Compared with CFBB, BBSF significantly (P<0.05) increased live weight, and decreased mortality (0.26%-0.87% vs 0.72%-2.47%), ratio of feed to meat (1.10-2.29 vs 1.17-2.46), and market elimination rate (0.87% vs 1.90%). Our results indicate that BBSF has better effects on controlling airborne microbial environment and improving duck production performances compared with CFBB. This study provides theoretical and technological supports for application of the novel BBSF system in the modern duck industry.