author(s)
S Usha, TK Mohanty and TK Patbandha

abstract
The present study was conducted on Holstein Frisian crossbred calves (96 healthy, diseased calves 32 diarrhoea and 32 pneumonia) of age within one month at Livestock Research Center, ICAR-National Dairy Research Institute, Karnal, India over a period of one year. The serum immunoglobulin (IgG) concentration below one month of age in normal and diseased calves in all four seasons was estimated. The serum immunoglobulin IgG concentration in normal healthy winter born calves was highest 26.45 ± 0.67mg/ml followed by autumn season calves 26.12±1.09 mg/ml and rainy season calves 25.04 ± 1.21 mg/ml. The lowest level was observed in summer born calves 23.86 ± 0.68 mg/ml. In diseased calves immunoglobulin concentration was highest in winter season 21.62 ± 0.74 mg/ml followed by rainy and summer season 20.19 ± 1.21 and 20.1 ± 1.07 mg/ml respectively. The lowest level was observed in autumn season 18.85 ± 1.36 mg/ml. The incidence of diarrhoea was highest in rainy and autumn season compare to other season and mortality was high in summer season compare to other seasons. This may be due to deficient immune status of calves in these seasons compare to other season. So by analyzing the serum immunoglobulin IgG level we can predict the morbidity and mortality of a calf in a farm level.