Analysis of mortality pattern among indigenous and upgraded pigs under subtropical hill agro climatic conditions in eastern Himalayas

Mortality records of indigenous and upgraded pigs, reared under subtropical hill agro climatic conditions, were collected for the period of 11 years (1993–2003), analyzed and the mortality pattern was correlated with genetic group, age of pigs, climatic factors and causes of death. Results revealed that there was significant (p < 0.05) difference in mortality between the indigenous (6.05%) and upgraded (5.64%) pigs. The mortality percentage was significantly (p < 0.05) higher in both genetic groups between 0 and 4 months of age compared to seven months and above age groups. Among different seasons, significantly (p < 0.05) higher mortality was observed during post-monsoon and winter compared to other seasons. The overall mortality percentage was 4.74, 5.25, 7.51 and 6.56 during pre-monsoon, monsoon, post-monsoon and winter seasons, respectively. Indigenous pigs recorded significantly (p < 0.05) higher pre-weaning mortality (14.26%) than the upgraded (9.58%) pigs. Among different causes, digestive disorders accounted to significantly (p < 0.05) higher mortality followed by miscellaneous and respiratory disorders. The study developed a linear regression model, which could fairly predict the mortality pattern based on the rainfall, relative humidity and temperature (R2 = 58.3%).