Pregnancy is a condition when a fetus began to develop in the uterus of the cow. Early pregnancy detection becomes important as it would determine the success of breeding management as well as to achieve the best productivity. This study aimed to evaluate and observe the pregnancy rate and reproductive disorders of Brahman Cross (BX) cows and compare the results to the Ultrasonography (USG) observation. The materials of the study were 80 BX cows selected through a purposive sampling method with

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... the following criteria: aged 2-3 years, weighed 300-500 kg, has at least calved once and had the body condition score (BCS) at 4-7 (in 1-9 scale). This study was conducted as experimental research, with 40 BX cows were artificially inseminated with Ongole crossbred (PO) semen at 0-2 h interval and the other 40 BX cows were at 8-10 h interval from the estrous detection. All of the BX cows were firstly synchronized with PGF2α (LUTALYSE) and then inseminated with PO semen (>40% motility) as according to the Indonesian standard. The pregnancy rate of the BX cows was observed through rectal palpation and 17β-estradiol hormone observation and further examined for the reproductive disorders by using USG. The obtained data were then analyzed descriptively and the results showed that 0-2 h insemination had a higher success of pregnancy (32.5%) compared to the 8-10 h interval (27.5%). Moreover, the highest 17βestradiol in the inseminated BX cows was at 5,765 ng/ml, while the lowest was at is 0.41 ng/ml. The USG observation showed that 6 BX cows (7%) in this study had a follicular cyst, 2 BX cows (2.25%) had persistent corpus luteum and 1 BX cows (1.25%) had ovarian hypofunction.