Disease dynamics in piglets in government breeding and backyard farms in Bhutan

Abstract

The seroprevalenceof porcine circovirus type 2 (PCV2), swine influenza virus H1N1 (SIV, H1N1), and Hepatitis E Virus (HEV) were previously found to be significantly higher in the government pig breeding farms than in the backyard farms. Therefore, there could be a risk of transmission and spread of these diseases (PCV2, SIV H1N1 and HEV only, not other diseases) to the backyard pig farms from government breeding farms through distribution of piglets. The main aim of this study was to to assess the dynamics of these diseases in piglets that are supplied from government breeding farms, with possible difference in infection dynamics between piglets being supplied to backyard farms and piglets retained in the breeding farms as replacement stocks. A survival analysis revealed no differences in overall seroconversions between piglets raised in government farm or in backyard farms, even though seroprevalence for PCV2 and HEV were significantly higher in piglets raised in government herds. Government breeding farms supplying piglets for fattening to backyard farms could promote the spread of diseases that are endemic in these farms. Depending on the damages these endemic diseases may cause in the backyard system, an increased level of disease control and biosecurity measures is warranted.