Inclusion of the yerba-mate extract on growing lambs\' diet: effects on health, performance, nutrition, methanogenesis, and meat quality

Author(s)

Richard Roberto Lobo

• Document type: Master's Dissertation
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT)
• Defense date: 2019-12-11

Examining board members

Ives Cláudio da Silva Bueno; Adibe Luiz Abdalla; Jessica Moraes Malheiros

• Advisor: Ives Cláudio da Silva Bueno; Rafael Silvio Bonilha Pinheiro

Abstract

The objective of this study was to evaluate increasing levels of inclusion of yerba mate extract as an additive in animal nutrition and its effects on health, performance, nutrition and digestibility of diets, in vivo methanogenesis, ruminal microbiome and meat quality. Thirty six male uncastrated and crossbred lambs (Îlle de France x Dorper x Santa Inês) with initial weight of 23.77 ± 3.70 kg were used for this study. The animals were divided into nine groups, the 4 animals in each group had similar weights, and were randomly assigned into one of the 4 treatments, which consisted of a control and 3 other treatments with increasing levels of yerba mate extract inclusion (1, 2, and 4%). The first three days, all animals received the control treatment, and on the third day ruminal fluid was collected via orogastric tube and blood to obtain baseline values, then began to receive the proposed treatment. Periodic weighting procedures were performed for monitoring, and daily dry matter intake was measured, 10% residue was desired to characterize an ad libtum diet. On the 30th day of period, 24 of the 36 animals were equipped with total fecal collection bags, which were adapted for 3 days and collected for 5 days for the apparent digestibility of diets. On the 39th day, the same 24 animals were equipped with methane measuring devices, using the SF6 tracer gas technique, 3 days of adaptation to the equipment and 5 days of collection. The animals were kept for 53 days, at the end of this period, a last weighing was performed and body biometric measurements were performed, ruminal fluid and blood collection were performed. After 16h of fasting the animals were slaughtered and carcass yield and carcass biometrics measurements were performed. A Longissimus thoracis muscle sample was collected and immediately stored in liquid nitrogen after slaughter for metabolomic analysis. Another sample after 24h of refrigeration was collected and stored under vacuum for meat quality analysis. The experimental design was randomized blocks and the results were analyzed by SAS studio 15.1 by the MIXED procedure. Results show that moderate levels (up to 2% inclusion) of yerba mate extract may improve animal immune system and overall performance. As well as increasing dry matter intake and digestibility of some nutrients such as total fiber and NDF. Higher musculature and lower fat cover were observed in animals receiving mate extract, as well as reduction in blood fat. No effect on methane emission per unit of production was identified and the extract did not change the alpha diversity of the rumen microbiome. (AU)

• FAPESP's process: 17/25319-0 - Inclusion of yerba mate extract in diets termination for sheep: effects on methanogenesis and meat quality
• Grantee: Richard Roberto Lobo
• Support Opportunities: Scholarships in Brazil - Master