Rocha Wéder Jânsen B, Silva Robério R, da Silva Fabiano F, de Carvalho Gleidson G P, da Silva Ana Paula G, Silva João Wilian D, Paixão Tarcísio R, Freitas Tiago B, Mendes Fabrício Bacelar L, Barroso Daniele S, de Souza Sinvaldo O, Santos Laize V
Instituto Federal do Sertão Pernambucano, PE 647, Km 22, PISNC N-4, Zona Rural, Petrolina, PE, CEP 56.302-970, Brazil.
Universidade Estadual do Sudoeste da Bahia, Praça Primavera, 40, Bairro Primavera, Itapetinga, BA, CEP 45700-000, Brazil.
Trop Anim Health Prod. 2019 Jul;51(6):1413-1420. doi: 10.1007/s11250-019-01824-2. Epub 2019 Feb 6.
The objective of this trial was to evaluate intake, digestibility, and growth performance of Girolando bulls submitted to two nutritional planes while grazing on Brachiaria brizantha cv. Marandu pasture. Twenty-two animals, with average initial body weight = 209.1 ± 8.2 kg, were used in this trial. The experimental design was repeated measurements, in a 2 × 3 factorial arrangement, with two nutritional planes (NP1 and NP2) and three seasons of the year, with 11 replicates per treatment. The animals of the NP1 received mineral mixture ad libitum during rainy season 1 (15 February through 5 July 2014), energy protein supplement in the amount of 1 g d kg BW during the dry season (from 6 July through 22 November 2014), and again mineral mixture ad libitum during rainy season 2 (from 23 November 2014 through 9 March 2015). The NP2 animals received 2 g d kg BW, 2 g d kg BW, and 1 g d kg BW of energy-protein supplement in the respective seasons of the year. Forage intakes were similar between nutritional planes, 6.8 and 7.6 kg DM day and 2.1 and 2.22% BW for NP1 and NP2, respectively. There was no statistical difference (level) between the intakes of neutral detergent fiber corrected for ash and protein (4.1 and 4.3 kg day and 1.2 and 1.3% BW, respectively for nutritional planes 1 and 2). For the other nutrients, NP2 showed greater values. The highest intakes and digestibilities of dry matter, organic matter, and non-fiber carbohydrate were in rainy season 2. Performance and feed conversion were similar among NPs. This study showed that lower levels of supplementation could be done in order to reduce feeding costs with no impact on performance.
本试验的目的是评估在放牧于臂形草属的马兰杜品种牧场上时，处于两种营养水平的吉罗兰多公牛的采食量、消化率和生长性能。本试验使用了22头动物，平均初始体重为209.1±8.2千克。试验设计为重复测量，采用2×3析因设计，有两种营养水平（NP1和NP2）以及一年中的三个季节，每个处理有11个重复。NP1组的动物在雨季1（2014年2月15日至7月5日）自由采食矿物质混合物，在旱季（2014年7月6日至11月22日）按每千克体重每天1克的量补充能量蛋白补充剂，在雨季2（2014年11月23日至2015年3月9日）再次自由采食矿物质混合物。NP2组的动物在一年中的相应季节分别按每千克体重每天2克、2克和1克的量补充能量蛋白补充剂。两种营养水平下的牧草采食量相似，NP1和NP2分别为每天6.8和7.6千克干物质，占体重的2.1%和2.22%。经灰分和蛋白质校正后的中性洗涤纤维采食量之间无统计学差异（水平）（营养水平1和2分别为每天4.1和4.3千克，占体重的1.2%和1.3%）。对于其他营养素，NP2组的值更高。干物质、有机物和非纤维碳水化合物的最高采食量和消化率出现在雨季2。不同营养水平之间的性能和饲料转化率相似。本研究表明，可以采用较低水平的补充来降低饲养成本，而不影响性能。
