A PROTEIN BANK EVALUATION, UNDER CUTTING OF Arachis pintoi (CIAT 18744) FOR FEEDING REPLACEMENT CALVES IN AN INTENSIVE MILK SYSTEM. BUGABA, PANAMA. 2000.

Abstract

Arachis pintoi legume (CIAT 18744) was evaluated as cutting forage, or as a protein source for feeding replacement suckling (3 months) calves from 3 to 6 months age old. This study was conducted over 275 masl, in a Pre-mountain Humid Forest with a tropical humid climate for 82 days (August to November, 2000). Three treatments were tested: T1 (2.0 kg of concentrate + grazing), T2 (5.0 kg of A. pintoi CIAT 18744 + grazing), T3 (1.0 kg of concentrate + 5.0 kg of A. pintoi + grazing). Four calves were randomly assigned to each treatment. Six experimental plots (2,000 m² each) of Digitaria swazilandensis (60%) and Cynodon dactylon cv. Alicia (40%) were utilized. A rotating grazing of 5-6 days with 24 to 30 rest days was used. The starting animal unit was 4.0 AU/ha; the maintenance fertilization was 150, 50 and 10 kg of N, P₂O₅ and K₂O/ha/year, respectively. A split plot statistical analysis, over the time, was performed. There was no significant effect among treatments (P>0.05). Daily weight gain (DWG) for treatments 1, 2 and 3 was 0.575, 0.416, and 0.478 kg/animal/day, respectively. A. pintoi (in natura or fresh base), 4.61 and 4.31 kg/animal/day, was offered. This legume presented a dry matter equivalence of 0.933 (0.299 -1.186) and 0.866 (0.326 -1.097) kg/animal/day for T2 and T3, respectively. Mean ingestion of A. pintoi on a normal "as fed" basis, was 0.801 and 0.796 kg/head/day for T2 and T3, respectively. The rejected amount of A. pintoi on a dry basis was 0.259 in T2 and 0.069 kg/animal/day in T3. The bigger dry matter intake of A. pintoi observed in T3 was associated with a higher DWG. Under the conditions this evaluation was conducted T1, T2 and T3 just covered 84, 54 and 80% (respectively), of the dry matter requirements; where the reduction of the dry matter of offered pastures (kg MS/100 kg BW) affected treatment responses, mainly for those in which concentrates were not given (T2). Variable costs (feeding and management) were B/. 0.40, 0.45 and 0.65 animal/day for T1, T2 and T3, respectively. The utilization of A. pintoi as cutting forage alone, or as a complement for concentrates in feeding replacement calves allows an acceptable DWG. Even though, its DWG is 20-38% lower than those obtained in intensive feeding system using concentrates, it is still better than semi-intensive and doubled (milk/meat) production systems.