الفهرس 
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Abstract
A total of 677 cows were included in the current study: 487 Holstein, 104 Flickvieh x Holstein, and 86 Brown Swiss x Holstein through the period from 2014 to 2019. Data of the present study were collected from a dairy farm, 28 km Esmailia-Cairo desert road. The aim of the present study was to evaluate the production and reproduction performance of Holstein, Holstein x Flickvieh (F1 crossbred; 50 % FK and 50 % HO), and Holstein x Brown Swiss (F1 cows; 50 % BS and 50 % HO) cows. The studied traits were (total milk yield (TMY), 305-days milk yield (305-DMY), days in milk at peak (DIM/Peak), dry period (DP), peak milk yield (kg), lactation length , persistency of milk production, milk composition traits, age at first calving (AFC), service per conception (S/C), days open (DO), calving interval (CI), conception rate (P/AI 28), embryonic loss rate, abortion rate, calving difficulty, retained placenta, endometritis and general health traits and culling).
The present results revealed that:
1. The pure HO cows had significantly greater 305-MY (8487 kg) than the HF and HB crossbred cows (8142 and 8058 kg, respectively).
2. The pure HO cows also produced significantly greater total-MY (10256 kg) than HF and HB crossbred cows (9034 and 9026 kg, respectively).
3. The pure HO cows had significantly higher peak-MY (36.7 kg) compared with the crossbreds (35.9 and 34.2 kg, respectively).
4. The pure HO cows had significantly longer lactation period (385.5 days) in comparison with the HF and HB crossbred cows (348.9 and 371.8 days, respectively).