Banca de DEFESA: MELANY SIMÕES DE SOUZA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MELANY SIMÕES DE SOUZA
DATE: 28/02/2023
TIME: 14:00
LOCAL: Online plataforma Meet
TITLE:

EFFECTS OF  ADDITIVES ON THE FERMENTATION QUALITY AND AEROBIC STABILITY OF CORN, SUGARCANE AND GRASS-LEGUME MIXED SILAGES

KEY WORDS:

buffering capacity, aerobic stability, grasses, yeasts

PAGES: 40
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
SUMMARY:

Effect of chemical additives and packing density on mixed forage silage quality. Successful silage production can be challenging for dairy farmers because some legumes and grasses included in forage mixes have a higher buffering capacity compared to other crops commonly grown for dairy cattle. The use of additives in the mixed forage ensiling process can modulate fermentation, decreasing production of total acids in the silage and the growth of undesirable microorganisms, such as yeasts and molds. Thus, the objective of this experiment was to evaluate the effects of a chemical additive and packing density on the fermentation profile and nutrient composition of mixed forage silage. Our hypothesis is that the chemical additive would improve the silage fermentation profile, but this response would be greater when the silage was poorly compacted. The experiment was conducted in a randomized block design with a 2 × 3 factorial arrangement with 6 treatments (two chemical additives × three packing densities) and four replications. Each silo was treated individually without (Control [CON]; 30 ml of distilled water) or with an additive solution of sodium sulfite, sodium metabisulphite and fungal amylase (Additive [ADD]; containing a minimum of 8% sulfur and aiming 0.11% of fresh forage. The forage was ensiled in silos with maximum packing density (D100, 215 kg of DM/m3), 75% of the maximum density (D75, 161 kg of DM/m3) or 50% of the density maximum (D50, 108 kg DM/m3). The silos were opened after 30 days of storage. pH, microbial counts, fermentation profile and nutrient characterization were evaluated. The silage treated with additive showed lower (P ≤ 0.01) concentrations of total acids, lactic acid, acetic acid and ethanol compared to control. No chemical additive effect was observed on yeast and mold counts. In the experiment, D50 treatments had higher (P ≤ 0.01) pH and counts of yeast and molds compared to D100 silage. Although there was a higher contagion in yeast and mold on D50 silage, there were minimal changes in nutrient composition, regardless of treatment.

BANKING MEMBERS:
Presidente - 1331235 - THIAGO CARVALHO DA SILVA
Externo ao Programa - 1974699 - EBSON PEREIRA CANDIDO
Externo à Instituição - ANIBAL COUTINHO DO REGO - UFC
Externo à Instituição - EDSON MAURO SANTOS - UFPB
Externo à Instituição - ODILON GOMES PEREIRA - UFV