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Ferreira, Igor Machado
;
Mantovani, Hilario Cuquetto
;
Viquez-Umana, Fiorella
;
Granja-Salcedo, Yury Tatiana
;
Costa e Silva, Luiz Fernando
;
Koontz, Anne
;
Holder, Vaughn
;
Pettigrew, James Eugene
;
Rodrigues, Arlan Araujo
;
Rodrigues, Aline Naime
;
Inacio de Abreu, Mateus Jose
;
de Almeida, Saulo Teixeira Rodrigues
;
Vidigal, Pedro Marcus Pereira
;
Siqueira, Gustavo Rezende
;
de Resende, Flavio Dutra
Número total de Autores: 15
|
| Tipo de documento: | Artigo Científico |
| Fonte: | JOURNAL OF ANIMAL SCIENCE AND BIOTECHNOLOGY; v. 16, n. 1, p. 18-pg., 2025-07-07. |
| Resumo | |
Background The environmental impact of feedlot operations is a growing concern, as cattle excrete a significant portion of feed nutrients as waste. Exogenous feed enzymes (EFE) have gained interest for their potential to enhance feed efficiency in ruminants by improving nutrient digestion. However, EFE effects on ruminal parameters have shown inconsistencies, with limited research on nitrogen metabolism and rumen microbiome impacts. Moreover, the synergistic effects of combining different EFEs remain unclear. This study aimed to evaluate the effects of individual and combined EFE products in feedlot diets on ruminal fermentation parameters, nitrogen metabolism, and ruminal microbial communities. Ten rumen-cannulated Nellore steers [543 +/- 28.6 kg of body weight (BW)] were distributed in a replicated Latin-square design (5 x 5) in individual pens. Treatments included: control (CON, no EFE supplementation), amylase [AML, 0.5 g/kg of diet dry matter (DM)], xylanase (FBL, 0.9 g/kg DM), half dose combination (HD, 0.25 g of AML + 0.45 g of FBL/kg of DM), and full dose combination (FD, 0.5 g of AML + 0.90 g of FBL/kg of DM). The experimental period lasted 19 d and included total urine and feces collection (d 15 to 18) and rumen fluid sampling (d 19) at 0, 4, 8, 12, and 16 h post-feeding for ammonia, volatile fatty acids (VFA), pH and microbiome analysis. Results EFE supplemented animals exhibited lower ruminal ammonia concentrations (P = 0.040), and higher acetate proportions (P < 0.001) compared to the control group. EFE supplementation resulted in reduced nitrogen (N) excretion in feces (P = 0.049) and urine (P = 0.036), contributing to improved N retention and efficiency (P = 0.045). Additionally, EFE products induced shifts in various microbial taxa at family and genera levels (P <= 0.10), which may be associated with the changes observed in ruminal fermentation. Conclusions Our findings demonstrate that EFE supplementation enhances nitrogen retention, reduces ruminal ammonia, and alters ruminal fermentation profiles and microbial populations in feedlot cattle. While the expected synergism between amylase and xylanase did not significantly impact rumen fermentation parameters, it did induce shifts in the rumen microbiome. These results suggest that EFE supplementation may be a promising strategy for improving nutrient utilization and potentially reducing the environmental impact of feedlot operations. (AU) | |
| Processo FAPESP: | 22/00989-1 - Utilização de enzimas exógenas em dietas de confinamento:efeito sobre a digestibilidade, metabolismo, desempenho,consumo, características de carcaça e genes diferencialmente expressos de bovinos nelore |
| Beneficiário: | Igor Machado Ferreira |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 17/50339-5 - Plano de desenvolvimento institucional de pesquisa do Instituto de Zootecnia (PDIp) |
| Beneficiário: | Lenira El Faro Zadra |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Modernização de Institutos Estaduais de Pesquisa |
| Processo FAPESP: | 19/24820-3 - Impacto do manejo do pastejo na recria de novilhas da raça Nelore com suplementação intensiva sobre o desempenho e parâmetros reprodutivos |
| Beneficiário: | Igor Machado Ferreira |
| Modalidade de apoio: | Bolsas no Brasil - Mestrado |