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چکیده
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In the first weeks of lactation, dairy cows often do not consume enough DMI to meet their nutrient requirement, which leads to a negative energy balance (NEB). The NEB is the reason for the most infectious diseases and metabolic disorders during the early lactation. Lysophospholipids (LPL) have been identified as novel highly potent feed additives. There is some evidence that LPL can increase dietary nutrient absorption and has anti-inflammatory properties. The objectives of this study were to investigate the effects of LPL on the performance and some reproduc- tion parameters of Holstein early lactation dairy cows. Therefore, 18 Holstein early lactation dairy cows (DIM = 25 ± 5) were used in a repeated measurement design (n = 9). Treatments were; control (CON, no additive), LPL (Lipidol Ultra, Easy Bio Inc.) at 15 g/d/cow. This experiment consisted of 4 periods that lasted 21 d (14-d diet adapta- tion and7-d sampling). For evaluation of the effects of treatments on the number and diameters of mature follicles of ovaries, cows’ estrous cycles were synchronized at the beginning of the experiment. Then, the number of mature follicles (15mm<) and their diameters were measured by ultrasound at d 21 after estrous synchronization. Findings from this study indicated that LPL supplementation resulted in an increase (p< 0.05) in the milk yield (52.6vs. 45.1 kg/d), FCM 3.5% (49.7 vs. 43.9 kg/d), and ECM (32.8 vs. 29.4 kg/d), relative to the control group. Lipidol supplementation at 15 g/d/head in the condition of the present study increased the number of mature follicles (1.7 vs. 1.2), mature follicles diameters (19.3 vs. 16.9, mm), and serum estradiol (155.7 vs. 75.9, ng/mL) concentration. The present study demonstrated that LPL supplementation could improve the performance of early-lactation dairy cows.
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