To investigate the impacts of various sources of omega-3 on feed intake, digestibility, and blood metabolites in horses, this research was conducted. In this survey, 6 medium-sized Turkmen horses, aged 14 to 16 years, were used. The horses had no movement and health problems. This research was carried out in the form of a rotating design and included 3 periods, and each treatment had 2 repetitions in each period. In each experimental period, horses were randomly assigned to each of the 3 experimental treatments. The experimental treatments included C) Omega-3-free supplement (control treatment), R) Persialin flaxseed oil, and P) Persialin fat powder. At the beginning of each period, after the withdrawal period for the previous period, blood and feces samples were taken as the covariate factors, then the experimental treatments were consumed for 14 days, and after the adaptation to 100 grams of supplementing fat powder or flax seed oil, blood, and feces samples were taken at the end of the course. Fat supplements were added to the concentrate 1.5 hours before feeding the midday hay. The palatability was affected by the P treatment and was significantly lower than the R and C groups (P<0.05). But the difference between the two treatments (R and C) was insignificant in any of the periods. The digestibility of acid detergent insoluble fiber (ADF), crude protein (CP), ether extract (EE), and organic matter were not affected by any of the experimental treatments. Blood metabolites including glucose, cholesterol, triglyceride, total protein, and blood urea nitrogen were not influenced by experimental treatments. The serum albumin concentration of horses was affected by the R treatment in the first and third periods, but no significant difference was observed between the treatments in the second period.