Detalhes bibliográficos
| Ano de defesa: |
2016 |
| Autor(a) principal: |
SIQUEIRA, Michelle Christina Bernardo de
 |
| Orientador(a): |
FERREIRA, Marcelo de Andrade |
| Banca de defesa: |
NOVAES, Luciano Patto,
URBANO, Stela Antas |
| Tipo de documento: |
Dissertação
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal Rural de Pernambuco
|
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Zootecnia
|
| Departamento: |
Departamento de Zootecnia
|
| País: |
Brasil
|
| Palavras-chave em Português: |
|
| Área do conhecimento CNPq: |
|
| Link de acesso: |
http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6976
|
Resumo: |
It was evaluated the effect of inclusion of spineless cactus (0, 14.7, 29.4, 44.1, and 58.8% of dry matter (DM) basis) by of replacement of Tifton hay on the intake, total and partial (ruminal and intestinal) digestibility, ingestive behavior, neutral detergent fiber dynamics, rumen parameters, and nitrogen compounds balance. Five crossbred steers, rumen fistulated, with average body weight of 380 ± 5.3 kg were assigned to a 5 × 5 Latin square design. The nutrient intake showed a quadratic effect, with a maximum intake of DM (8.89 kg/day), organic matter (OM, 7.88 kg/day), crude protein (CP; 1.35 kg/day), and digestible OM (DOM, 5.75 kg/day) estimated with 33.9, 31.6, 29.9, and 41.8% of inclusion, respectively. The total and ruminal digestibility of DM, OM, and CP linearly increased, however, there was linear decrease on the total and ruminal digestibility of neutral detergent fiber (NDF). The intestinal digestibility of DM and NDF linearly decreased, however, there was no effect for OM and CP. There was no effect for idle times. The time spent with rumination activity linearly decreased with the inclusion of spineless cactus. However, the feeding time showed a quadratic effect, with minimum time of 195 min/day estimated with 35.7% of inclusion. The maximum pool of DM (3.77 kg) and NDF (2.46 kg) was estimated with 24.6 and 20.1% of inclusion, respectively. There was no effect on the ingestion rate (Ki) of DM and NDF and degradation rate (Kd) of NDF. However, linear decrease of Kp of DM and NDF and linear increase of Kd of DM were observed. The rumen pH linearly decreased with the inclusion of spineless cactus and showed a quadratic effect over the collection times. Quadratic behavior for ammonia nitrogen (28.2 mg/dL) estimated at 2.64 h after intake was verified, and there was no effect for the short-chain volatile fatty acids production with the inclusion levels. Except to plasma urea nitrogen and urinary urea nitrogen that were not affected, there was a quadratic effect on nitrogen balance, with maximum value of 170 g/d estimated with 33.2% of inclusion. It is recommended to include 41.8% of spineless cactus in the dry matter in replacement to Tifton hay in the diet of crossbred steers to maximize energy intake and nitrogen balance. Thus, it is suggested use the tifton hay:spineless cactus ratio of 28:42 with 30% of concentrate, in feeding programs of crossbred steers. |
