Dairy Cattle Breeding Division, National Dairy Research Institute, Kamal, Haryana -132001.
The data of 1200 Murrah buffalose consisting of various first lactation records which were spread over a period of 36 years (1970–2005) were analyzed for estimation of first lactation records by time series analysis. The traits considered were age at first calving (AFC) in days, first lactation 305-day of less yield (FL305DMY) in Kg, first lactation total milk yield (FLTMY) in Kg. first lactation length (FLL) in days, first service period (FSP) in days, first dry period (FDP) in days and first calving interval (FCI) in days. A periodicity of 7,5, 6, 5, 7, 7 and 7 years respectively was obsered in the above traits, The periodic functin was fitted and it explained minimum variation in the above traits ranging from 42.12 fof (FLTMY) to maximum variation of 90.34% (AFC) indicating the periodicity of data over the years in most of the traits and hence the animal breeding data has to be adjusted for cyclicity over the year.
