Sampaio Ricardo Linhares, de Resende Flávio Dutra, Reis Ricardo Andrade, de Oliveira Ivanna Moraes, Custódio Letícia, Fernandes Rodolfo Maciel, Pazdiora Raul Dirceu, Siqueira Gustavo Rezende
Beef Tec-Tecnologia em Pecuária, Campo Grande, Mato Grosso do Sul, 79020-122, Brazil.
APTA-Agência Paulista de Tecnologia dos Agronegócios, Colina, São Paulo, 14770-000, Brazil.
Trop Anim Health Prod. 2017 Jun;49(5):1015-1024. doi: 10.1007/s11250-017-1294-8. Epub 2017 Apr 26.
This study evaluated the nutritional interrelationship between the growing and finishing phases of crossbred cattle in determining their performance. One hundred and eight animals were used (8 months old, body weight [BW] 211 ± 20 kg). During the dry season, the animals received one of the following supplements: a mineral plus urea supplement (ad libitum, MSD), a protein supplement (1 g/kg BW per day, PR1), or a protein-energy supplement (5 g/kg BW per day, PE). During the rainy season, the animals received one of the following supplements: a mineral without urea supplement (ad libitum, MSR), a protein supplement (1 g/kg BW per day, PR2), or PE (5 g/kg BW per day). The experimental design was completely randomized using a 3 × 3 factorial scheme (for the rainy season) and a 3 × 3 × 2 factorial scheme (for the finishing phase). The supplementation and finishing systems were considered to be the treatments, and the animals were considered to be the experimental units. Dry season supplementation did not affect the average daily gain (ADG) during the rainy season (P = 0.12) or the finishing phase (P = 0.73). An increase in the level of rainy season supplementation reduced ADG by 12% during the finishing phase (P < 0.06). Providing PE during the dry and rainy seasons led to the animals being slaughtered 17 (P = 0.06) and 30 (P < 0.01) days earlier, respectively. Our results indicate that supplementation during the dry season (under poor-quality pasture conditions) does not affect the performance during the rainy season or the finishing phase. Furthermore, while providing PE during the rainy season can reduce ADG during finishing, the higher BW at the beginning of the finishing phase is sufficient to reduce the time of the finishing period.
本研究评估了杂交牛生长育肥阶段的营养相互关系对其生产性能的影响。试验选用了108头动物（8月龄，体重[BW]211±20千克）。在旱季，动物接受以下补充料之一：矿物质加尿素补充料（自由采食，MSD）、蛋白质补充料（每天1克/千克体重，PR1）或蛋白质-能量补充料（每天5克/千克体重，PE）。在雨季，动物接受以下补充料之一：不含尿素的矿物质补充料（自由采食，MSR）、蛋白质补充料（每天1克/千克体重，PR2）或PE（每天5克/千克体重）。试验设计采用完全随机化，旱季为3×3析因设计，育肥阶段为3×3×2析因设计。补充料和育肥系统被视为处理因素，动物被视为试验单位。旱季补充料对雨季（P=0.12）或育肥阶段（P=0.73）的平均日增重（ADG）没有影响。雨季补充料水平的增加使育肥阶段的ADG降低了12%（P<0.06）。在旱季和雨季提供PE分别使动物提前17天（P=0.06）和30天（P<0.01）屠宰。我们的结果表明，旱季（在劣质牧场条件下）补充料不影响雨季或育肥阶段的生产性能。此外，虽然雨季提供PE会降低育肥期的ADG，但育肥阶段开始时较高的体重足以缩短育肥期。
