Nutritive value of pastures of Cynodon mixed with forage peanut in southwestern Paraná State

This study evaluated the nutritive value of pastures of Coastcross-1 and Tifton 85 mixed with increasing inclusion of forage peanut (0, 25, 50, 75% occupancy area), subjected to cuts, over two study years in Southwestern Paraná State. The experimental design was factorial (three factors) distributed in randomized block. The factors were cultivars (2), the occupancy area of forage peanut (4) and seasons of cuts (5), with three replications. It was evaluated the percentage of crude protein, neutral detergent fiber and in vitro digestibility of dry matter of leaf blades, stem + sheath of grasses and available forage mass of pastures. Values of crude protein ranged from 17.0 to 20.4% and from 16.8 to 19.3% for the forage mass available of Coastcross-1 and Tifton 85, respectively. Higher digestibility values were found at the beginning of evaluations. On average, the Coastcross-1 showed better nutritive value compared to Tifton 85, and, the inclusion of forage peanut increased crude protein content in leaf blades of grasses studied, in the second year after planted.

本研究于巴西巴拉那州西南部开展，试验周期为两年，针对设置了不同饲用花生（forage peanut）占比面积（0%、25%、50%、75%）混播组合的Coastcross-1与Tifton 85牧草牧场，在刈割处理下的营养价值进行了评估。试验采用三因子随机区组设计，因子分别为牧草品种（2个）、饲用花生占比面积（4个梯度）、刈割季节（5个），每组设置3次重复。本研究测定了牧草叶片、茎秆+叶鞘的粗蛋白（crude protein）、中性洗涤纤维（neutral detergent fiber）含量、干物质体外消化率（in vitro digestibility of dry matter），以及牧场可利用饲草产量。结果表明，Coastcross-1与Tifton 85的可利用饲草粗蛋白含量分别为17.0%~20.4%和16.8%~19.3%；试验初期测得的消化率数值更高。整体而言，Coastcross-1的营养价值优于Tifton 85；在种植后的第二年，提升饲用花生的占比可提高供试牧草叶片的粗蛋白含量。