Termination of lambs fed concentrate or pasture: performance and technical feasibility

• Autor(a) principal: Saccol, Ana Gabriela Freitas
• Data de Publicação: 2020
• Outros Autores: Pires, Cleber Cassol, Klinger, Ana Carolina Kohlrausch, Pötter, Luciana, Seibert, Liane, Lopes, Jusecléia Ferreira, Quadros, Fernando Luiz Ferreira, Costa, Silvio Teixeira
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Semina. Ciências Agrárias (Online)
• Texto Completo: https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/36729
• topic: High grain; Natural pasture; Ryegrass; Zootechnical performance; Lambs farming.; Alto gão; Azevém; Pastagem natural; Desempenho zootécnico; Criação de cordeiros.

A total of 28 uncastrated lambs, with 20kg of body mass (BM) were distributed into two different finishing systems where animals were fed either concentrate (CFS) or pasture (PFS) until 35 kg BM. The CFS diet consisted of 77.4% of corn grain; 20.2% soybean meal; 1.4% limestone and 1.0% sodium bicarbonate. The PFS diet consisted of both native pasture and ryegrass. The evaluated parameters were: dry matter intake (DMI), organic matter intake (OMI), crude protein intake (CPI), neutral detergent fiber intake (NDFI), feed conversion (FC), mean daily gain, days to reach 35kg BM, ruminal pH, in vivo biometric measurements, carcass composition, percentage of commercial cuts, pallet composition, and proportion of body components. The CFS animals had higher DMI, OMI, CPI and lower NDFI when compared to PFS. Also, animals feed CFS presented higher mean daily gain and better FC. Animals from CFS took 77 days to reach 35kg BM whereas animals from PFS took 278 days. The ruminal pH was higher, and more adequate, in the PFS group when compared to the CFS group. The CFS lambs presented better quantitative characteristics and conformation, and higher fat deposition. PFS lambs, on the other hand, provided leaner and more muscular carcasses. Thus, the termination of lambs without use of bulky feed is technically feasible and provides better zootechnical performance and carcass characteristics. However, the ruminal pH drop may compromise the system and must be observed.