Effect of replacing solvent soybean meal with extruded soybean meal on ‎performance and metabolic status of Holstein fresh cows

The objective of this study was to compare solvent soybean meal with extruded soybean meal at 135°C on performance and metabolic status of fresh Holstein cows. Twenty-four Holstein cows (BW± SD; 614.45± 28.33) were randomly assigned to 1 of 2 experimental treatments from caving until 21 days in milk: 1- control (containing solvent soybean meal; SSBM) and 2- experimental (containing extruded soybean meal; ESBM). Cows were housed in individual stalls, fed with total mixed ration, and feed offered and ort were recorded daily. Milk yield was recorded daily and milk sampls were taken weekly to determine its composition. Body weight and body condition score of cows were determined at immediately after calving and 21 DIM. Dry matter intake in ESBM cows was greater than SSBM cows (P˂ 0.01). Cows fed ESBM produced 3.71 kg/d more milk than SSBM cows (P< 0.05). Milk fat content in ESBM cows was lower than SSBM cows (P<0.05). The ESBM cows had lower serum glucose concentration (P<0.01) and higher cholesterol (P<0.01) than SSBM cows. Rectal temperature, BCS and BW changes, and feed efficiency were not different between treatments (P>0.1). Overall, the results of this study showed that replacing solvent soybean meal with extruded soybean meal increased DMI and milk yield of fresh cows.