Mechanical processing during harvesting of snaplage on performance of beef cattle in feedlot

• Ano de defesa: 2022
• Autor(a) principal: Sant\'Anna, Daniel Furtado Dardengo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Snaplage; Animal performance; Desempenho animal; Roughage replacement; Silagem de milho planta inteira; Substituição de volumoso; Tamanho de partículas; TLOC; Whole plant corn silage
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/11/11139/tde-13042023-112255/

Snaplage is a rich source of energy due to the high potential share of grains. This ingredient has high-grain substitutes in the confinement of beef cattle in Brazil, in addition to the energy contribution, as the diet comes from the stalk and the husk of the ear. One in silage is mechanical, the mass size of conjugation of materials as processing for silage compaction, promoting a reduction and enhancing the digestion. Therefore, agronomic modification devices that can modify the crop and the proportion of grains on the ear and the respective chopping operation of the mechanical devices in snaplage crop processing. The objective of the present work is the first crop, to impose theoretical particle sizes in the snaplage crop and verify how they result in the performance of confined beef cattle; to identify the feasibility of using snaplage as a single source of roughage in the diet of beef cattle in a feedlot. Sixty-five Nellore animals were used in individual pens in a randomized complete block design. For the animals that received the snaplage treatments diets contained 30% by roughage and 70% of concentrate based on dry matter, for the animals that received the treatment with WPCS the diet contained 25% by roughage and 75% of concentrate based on dry matter. For the evaluation of animal performance, DMI, ADG, feed efficiency, HCW, dressing, LM area, and 12-th rib-fat and they used as indicators, as well as estimates of ingestive behavior and selection. In addition, density measurements, aerobic evaluation, microorganism measurement, and mean particle size were performed during the animal performance evaluation period, and the evaluation of animal performance, silage, diets, and orts were analyzed to measure chemical characteristics (DM, MM, after CP and NDF). In the present study, animals fed with whole plant corn silage, when compared to those fed a diet containing snaplage, showed higher dry matter intake, however, it did not result in changes in average daily gain, final body weight, and food efficiency. However, animals that received a diet containing snaplage harvested with a theoretical cut size of 9 mm had lower rumination time and carcass weight. As for the sorting index, the animals received a diet of whole plant corn silage (WPCS) harvested with 15 mm of refusal to the 8 mm sieve, probably because they had already supplied the fiber requirement. The theoretical sizes of SM particles found were different from those observed, therefore, were mean particle sizes (MPL) 6.6 were and 7.4 mm for snaplage and TMP found to 9.9 mm. Therefore, there was no difference in the performance of the animals fed with snaplage under sizes of partial variation of 6.6 and 7.4 mm and this small difference did not provide the difference between animal performance and, above all, that this ingredient behaved satisfactorily included in the proportion of 30% harvested and as the only source of roughage in the diet of confined beef cattle.