In the quest to enhance dairy cows’ performance naturally, this study examines how extruded linseed sup- plementation affects feed intake, milk production, nutrient digestibility, plasma parameters, and reproduc- tive performance in early-lactation Holstein dairy cows. A total of 400 first-lactation (primiparous) Holstein cows, averaging 35 ± 15 days in milk and 41 ± 9.8 kg/day milk yield per day, were assigned to two groups based on days in milk and milk production. They were fed either a control diet or one including 7% dry matter (DM) extruded linseed for 90 days. Results showed no significant effects on dry matter intake, 4% fat-corrected milk (4% FCM), energy-corrected milk (ECM), feed efficiency (FE), milk fat and protein content, and milk fat and protein production (P<0.05), nutrient digestibility, or blood urea nitrogen (BUN), non-esterified fatty acids (NEFA), albumin, globulin, total protein, triglycerides, calcium, magnesium, and plasma phosphorus concentrations. Plasma β-hydroxybutyrate and progesterone concentrations tended to decrease and increase, respectively, in cows fed diets containing extruded linseed compared to cows fed the control diet (P=0.09). However, cows on the llinseed diet exhibited slight reproductive benefits, including lower rates of abortion and embryo resorption. Overall, extruded linseed improved reproductive perform- ance marginally without affecting production performance
