الفهرس 
I. IntroductionOnly 14 pages are availabe for public view
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Abstract
This study was carried out on yearly time series data from 2013-2021in the first two farms and from 2016 – 2022 in the second farm on 2400 lactation farm records during Covid 19 occurance. 900 lactation records were belonged to Holstein Friesian and the other 900 lactation records were belonged to Holstein German. Moreover, the 600 lactation records were belonged to Simmental breed to forecast milk production. Areas of data collection were divided into two different regions. The first region was Dakahlia governorate and the second region where from Behira governorate. Time series data were collected, summarized and statistically analyzed using the statistical graphics program. The analytical design was ARIMA model. Results of the study:ARIMA model includes the following steps for Holstein Friesian: Model identification: At first, the data is checked for stationarity with the help of the autocorrelation (ACF) and partial autocorrelation function (PACF). we found that the data are located between 0.5 and – 0.5, which indicates that the data is stationarity. Model estimation: It means estimation of model fitness through estimation of best coefficients as ACI, MSE, MAPE and SBIC. The results indicated that ARIMA (2,1,2) model is the best fit model because it is the model with lowest values of fit measures as RMSE, MAE, MAPE, ME, MPE, AIC and SBIC. Model forecasting: Seven year forecast from 2022 to 2033 was done. Forecasting milk production for Holstein Friesian indicates that milk production will be increased at year 2022 and 2033. Milk production will be increased till reach 574313 kg in 2025 and 574183 kg in 2033. This indicates presence of variations in milk production forecasting between increase and decrease in future years.