Document Type : Original Article


Animal Production Research Institute, Agricultural Research Center, Dokki, Egypt.


The objective of this study was to evaluate the effects of flaxseed oil supplementation into the ration of Friesian cows on their productive, somatic cell count (SCC), physiological and blood parameters during summer season. Twenty four dry pregnant Friesian cows averaged 607±22.5 kg live body weight (LBW) at 2-3 parities were randomly assigned into two groups (12 cows in each group). Cows in group 1st (G1) did not treatment and served as a control, while those in the 2nd were c received 2% of DM intake flaxseed oil from 45 days pre-partum until 120 days post-partum. Results revealed that body temperatures degrees of rectal (RT), skin at white (STW) and black (STB) as well as respiration rate (RR) during heat stress period in summer months (June, July, August and September) significantly (P<0.05) decreased  with flaxseed oil as compared to the control group. Flaxseed oil diet improved (P<0.05) digestibility and rumen activity. Average daily dry matter intake (DMI) and DCP pre-partum were nearly similar for control and flaxseed oil treatment, while the intake of TDN increased significantly (P<0.05) with flaxseed oil supplementation compared to the control group. Cows of tested treatment On post partum state, DMI and TDN intake were significant higher with oil supplemental ration than the control group, but the difference did not significant between treatments respecting DCPI in this phase. Cows of treatments were higher in red blood cell (RBC) and white blood cell (WBC) counts, hemoglobin (Hb) concentration and haematocrit percentage (HCT, %) than those of the control group. Cows treatment were higher significantly lymphocytes and significantly lower moncytes than control group. All protein fraction concentrations were higher in treated than in control group (G1). Concentrations of high density lipoprotein and triglyceride were higher significantly (P<0.05) in G2 than the control group (G1), but, plasma low density lipoprotein concentrations were lower significantly (P<0.05) in G2 than the control group (G1). Daily milk yield and 4% fat corrected milk were higher significantly by 19.37 and 29.99%, respectively compared with control. The G2 had higher (P<0.05) percentages of fat, lactose and total solids as compared to G1, while protein and solids not fat percentages were similar to G1. Diet supplemented with flaxseed oil showed lower (P<0.05) somatic cell count in milk as compared to G1. Feed conversion improved (P<0.05) in G2 than in G1. Economic efficiency was higher with flaxseed oil- ration than that of control one free from oil. It could be concluded that flaxseed oil supplementation in diet of Friesian cows (2% /kg DMI) during pre- and post-partum period heat stress could be eliminated and improved digestibility, productive performance and economic efficiencies as well as immune-response of Friesian cows without adversity effects on haematological and biochemical parameters.