J. Sci. Agri. Technol. (2020) Vol. 1 (2): 14-20
This study determined growth performance and blood biochemical values of Thai native steers during 120 days of fattening. Twelve healthy three-year-old steers were assigned equally into two groups. One group was allowed free grazing on grassland improved mainly with purple guinea grass (Panicum maximum), and the other group was reared in feedlot fed with corn silage-base. Both groups supplemented with different crude protein concentrate diets due with 12 and 14 percent of about 1 percent of the bodyweight a day. The results found that steers on grassland were significantly higher average daily gain than those steers reared under feedlot conditions. There was no significant difference in these values between steers supplemented with either of the two protein diets. Blood biochemical values at the end of the trial were not significantly different for the steers fed with different dietary treatments. Glucose, alkaline phosphatase, albumin, mean corpuscular volume and, mean corpuscular hemoglobin after the trial increased, but free serum thyroxine and triiodothyronine decreased and differed significantly from the values at the beginning of the trial. Other blood biochemical values, triglyceride, total cholesterol, total bilirubin, direct bilirubin, aspartate serum transferase, alanine transaminase, blood urea nitrogen, and creatinine were not significantly different between the inception and the conclusion of the trial. Differences in dietary protein supplementation caused no differences in the blood biochemical values of the steers. These results imply that the Thai native steer should fatten on grassland with a 1 percent BW dietary supplemental concentrate of 12 percent of CP.
Keywords: performance, blood biochemical, grassland, feedlot, Thai native steer
Received: April 21, 2020. Revised: June 9, 2020. Accepted: September 29, 2020.