Evaluation of antioxidant potential of lemongrass (Cymbopogon citratus (D.C.) Stapf) on mammary gland apoptosis and milk quality of Saanen goats

Author(s)

Michele Ferreira Ribeiro

• Document type: Master's Dissertation
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT)
• Defense date: 2011-10-27

Examining board members

João Alberto Negrão; Andrezza Maria Fernandes; Ivanete Susin

• Advisor: João Alberto Negrão

Abstract

The objective of this study was to evaluate the antioxidant potential of lemongrass (Cymbopogon citrates (D.C.) Stapf) on the quality of goat\'s milk (production, composition, physical-chemical characteristics, somatic cell count, total bacterial count and lipid oxidation) before (Phase 1) and after punctual administration of ACTH (Phase 2), as well as mammary gland apoptosis (Phase 3) of milk goats of Saanen breed in lactation. In phases 1 and 2, 44 goats were fed ration composed by 53.2% of corn silage in dry matter (DM) (T1), where corn silage was substituted in 33.5% (T2), 66.5% (T3) and 100% (T4) by lemongrass pelletized hay. In phase 3, twelve goats at the end of lactation period (264.67 ± 31.86 days) were submitted to mammary gland biopsy. It was observed a numeric increase in dry matter intake (DMI) with the increase of lemongrass inclusion in two experimental phases (Phase 1 and 2) without, however, affecting milk production. The contents of fat and total solid in Phase 2 were higher in treatments T1 and T3 after stress induction through ACTH and were linearly reduced with increasing levels of lemongrass. There was no difference in total bacteria counts in milk in two experimental phases. Somatic cell counts were lower in treatment T2 after stress induction through ACTH and linearly reduced with the inclusion of increasing levels of lemongrass in Phase 2. Lipid oxidation in Phase 1 was not influenced by lemongrass inclusion but in Phase 2 there was linear reduction with lemongrass inclusion. The administration of ACTH did not influence milk lipid oxidation (Phase 2). There was no effect of lemongrass inclusion on DNA and RNA concentration, as well as in DNA fragmentation (Phase 3) in polyacrylamide gel 8%. However, it was observed quadratic effect in apoptotic cells counts with higher value for treatment T2. The inclusion of increasing levels of lemongrass in the feeding of dairy goats did not reduce the apoptosis of mammary gland, however, increased the oxidative stability of milk, proving its antioxidant effect. (AU)

• FAPESP's process: 09/07016-4 - Assessment of antioxidant potential lemongrass (Cymbopogon citratus (D.C.) Stapf) on the apoptosis of tissue mammary and milk quality of Saanen goats
• Grantee: Michele Ferreira Ribeiro
• Support Opportunities: Scholarships in Brazil - Master