Banca de QUALIFICAÇÃO: REBECCA BARBOSA SILVA
Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.DISCENTE : REBECCA BARBOSA SILVA
DATA : 15/06/2018
HORA: 13:00
LOCAL: ANFITEATRO DO INSTITUTO DE ZOOTECNIA DA UFRRJ
TÍTULO:
GENETIC POLYMORPHOSMS OF αS1-CASEIN IN DAIRY GOATS AND ASSOCIATION WITH THE QUALITY OF MILK TEXTILE FIBERS
PALAVRAS-CHAVES:
goats; polymorphism; micelles; caseins; protein filaments.
PÁGINAS: 22
GRANDE ÁREA: Ciências Agrárias
ÁREA: Zootecnia
SUBÁREA: Produção Animal
RESUMO:
Abstract: It is estimated that 12 to 15% of the milk produced annually in Brazil is discarded by physico-chemical changes in its composition. Its use in the elaboration of polymeric derivatives is an alternative that provides environmental and financial sustainability to all the sectors involved. The elaboration of textile fibers from milk proteins is an alternative to reallocate the milk of discard within the system of production. The fiber formed from the milk proteins is defined as an artificial protein chemical fiber and its characteristics will depend on the chemical composition of the milk used to produce it. The main component of milk in the production of these fibers is protein, especially caseins, which account for an average of 80% of total milk proteins. The casein micelle is formed by the subunits αs1, αs2, β, κ and by variants originating from genomic alterations that result in structural differences in the organization of the micelles and may be related to changes in the quality characteristics of the milky fiber. In goats, the genetic polymorphism at the locus of the gene encoding αs1-casein (CSN1S1) is intense and is associated with quantitative variations in the protein fractions of the milk, which confers changes in the conformation of the micelles. Thus, we aim to associate the existing polymorphisms in the αs1-casein gene in Saanen and Alpina goats with the quality of the textile fibers produced from milk proteins. It will be used 40 females of the Alpina and Saanen breeds from the capillary of the Federal University of Viçosa (UFV), which will be identified for the genotypes for the CSN1S1 locus and distributed in three groups: genotypes that result in milk with high, medium and low production of αs1-casein. For the production of the fiber, 500 mL of milk will be collected per genetic group and it will be skimmed. The process will have the following phases: casein coagulation, dissolution, spinning and coagulation of the filament. After conditioning, the quality of the fibers will be evaluated in a universal test machine (INSTRON®) in order to determine Young's burst strength, toughness, elongation and modulus. Scanning electron microscopy images of the fibers will be used to verify the morphological characteristics and fracture of the fibers using HITACHI TM3000 microscope. The characteristics of interest will be analyzed using the GLM (General Linear Model) procedure of the statistical program SAS (Statistical Analisys System, 1998).
MEMBROS DA BANCA:
Presidente - 1899630 - VINICIUS PIMENTEL SILVA
Interno - 2142739 - RODRIGO VASCONCELOS DE OLIVEIRA
Interno - 1721561 - MARIA AMELIA MENCK SOARES
Externo à Instituição - PAULO HENRIQUE DE SOUZA PICCIANI - UFRJ
Externo à Instituição - MARINA MORTATI DIAS BARBERO - UNESP
Externo à Instituição - MARCELO TEIXEIRA RODRIGUES - UFV