Abstract:
The aim of this study was to establish a Health and Demographic Surveillance System (HDSS) in the cattle population of the Mnisi community in Bushbuckridge, Mpumalanga Province, South Africa. The study provided data on the cattle population dynamics over 12 months, from July 2012 through June 2013. It focused on over 4,500 cattle in Ward B2 of the foot and mouth disease (FMD) control zone, comprising five diptanks, allowing for data recording on individuals and collecting information from farmers when they came once a week to have their cattle dipped and inspected for FMD. A baseline census was established for all the herds via individual identification by ear-tagging, gathering data such as age, gender, type and body condition. This information was updated weekly over 12 months with demographic parameters - herd dynamics, entries and exits. With an average herd size of 25.8 cattle, ranging from 1 - 138 animals per herd, farmers in the study area own more livestock than many other communal farmers in other regions of southern Africa. Herd structure differs from that reported in other studies, with breeding cows aged three years and older representing 55.8% of the herd and heifers 2%, resulting in one bull per 2.1 cows. As for the herd composition, Sanga types and their crosses make up most of the herds in Ward B2, and their average body condition score was 2.7 on a 1 - 4 scale. The calving rate of 40.1% is a good sign of herd fertility, and represents 86.3% of all entries into the study population. The mortality rate of 7.3% is low compared to other studies, and represents 76.8% of all exits. Due to the restriction on movements of FMD-vaccinated cattle, intake and offtake rates are low. Cattle herds in Ward B2 show signs of good health such as good body condition, low mortality rate and good reproductive performance. Over a year, the study population increased by 13.3%. Such a project can hopefully be the starting point for further HDSS work in the Mnisi community, which will refine population parameter estimates over the years by continuing weekly information recording.