Comparison of different lactation curve models in holstein and simental race cattle grown in Karacabey agricultural management directorate

In this thesis, daily 16 912 days milk yield record values of 56 cattle reared in the farm operating in Karacabey Agricultural Enterprise in Karacabey district of Bursa (38 of them Holstein, 18 of them Simental breed) were used. By using milk control yields with daily milk yield records Wood and Legendre (2, 3 and 4) models and real lactation curves were determined. The compatibility of the models were examined by determining the actual lactation yields and 7, 10, 15 and 30 day control interval values. In addition, the curves of lactation according to breeds were examined. R2(%), HKO and correlation values between real and forecast data were used as model comparison criteria. At the end of the study, in the estimation of lactation milk yield curve of black pied cattle R2 (%50.4), HKO (25.894), the correlation between real and forecast data (%71.0) values with the most appropriate model was determined to be Leg4. In the estimation of lactation curves of simental cattle R2 (%66.0), HKO (11.447), the correlation between real and forecasting data (%81.3) values with the most appropriate models were determined to be Leg4 and Wood.