Data of milk production and performance under Oman climatic conditions are limited. The current study presents a 9-year analysis of daily milk performance of Holstein and Jersey cattle breeds born and raised in Oman and fed similar diets of concentrate and Rhodes grass hay. Data on the daily cow's milk production, during the entire lactation period for nine consecutive milking years between 2009 and 2018, were collected. The data was introduced to a linear mixed model and was analyzed to evaluate the breed variations in milk production across lactations and across years. Holstein Friesian (HF) cows had significantly (P < 0.001) higher daily milk production of 17.6 ± 0.4 kg/cow/day compared to 11.7 ± 0.8 kg/cow/day for Jersey cows. Across years, we observed a gradual annual improvement in total milk production in both HF and Jersey breeds of 5% and 6%, respectively. The highest daily milk production was in the third and fourth lactations for HF cows and in the second and third lactations for Jersey cows. In a region where much of the expected demand in milk will be met by exotic breeds and importation, our results provide an insight into the performance of temperate breeds in hot and arid climatic conditions. As such, our results shall be useful for dairy producers seeking to maximize milk production under such conditions.
Keywords: Breed; Cows; Hot climate; Milk production.