Banca de DEFESA: ALINE BARROS DA SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : ALINE BARROS DA SILVA
DATE: 30/04/2021
TIME: 08:30
LOCAL: INSTITUTO DE ZOOTECNIA
TITLE:

Milk Production in Massai Grass Pastures in agrosilvopastoral Systems

KEY WORDS:

Megathyrsus maximus. Moderate shading system. Thermal comfort.

PAGES: 242
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Pastagem e Forragicultura
SUMMARY:

SILVA, Aline Barros da. Milk Production in Massai Grass Pastures in agrosilvopastoral Systems. 2021. 230 p. Thesis (Doctorate in Zootechnics, Animal Production). Instituto de Zootecnia, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, 2021. An improved animal husbandry environment generates great benefits in the production results, obtained within dairy farming in Brazilian tropical regions. The aim was to evaluate the productive and qualitative performance of massai grass, the performance animal behavior of crossbred cows subjected to shade regimes with eucalyptus and in monoculture (full sun system-SFS; moderate shade system-SMS and intensive shade system-SIS). The experiment was carried out at Embrapa Agrossilvipastoril (Sinop/MT) from 01/06/2018 to 06/14/2019. structural characteristics, grazing losses, forage utilization and offers, nutritive value forage of massai grass, microclimate, stocking rates, animal behavior, individual production and milk quality were evaluated. The data under univariate statistics by SAS® On Demand and PDIFF (P<0.10) and multivariate (discriminant and principal component analysis) analyses were performed. There was a 25 and 50% difference between the maximum PAR values of the SFS and the SMS and SIS, respectively. The average values of temperature and humidity indexes (THI) were higher than 72. The pre-grazing forage mass, leaf blade mass, and steam mass in SSM were intermediate to other production systems (6,885; 3,206; and 2,105 kg ha-1DM, respectively). The bulk density and utilization forage values were also intermediate in SMS (109.1 ha-1 cm-1DM and 2,999 kg ha-1DM on average) compared to other systems. Higher crude protein contents were obtained in SIS (13.6%), intermediate in SMS (11.3%) and lower in SFS (10.1%). In summer/2017, individual milk production was higher in SIS than in SFS, both similar to that in SMS (15.5 kg of milk cow-1 day-1). In the rainy season, cows in shaded systems sought shade more frequently (66.5% on average) than those in SFS (15.9%). In the dry period, the frequency was intermediate in SMS (59.7%), with a higher value for SIS (73.2%). Under conditions of low PAR, the steams of massai grass were less thick and heavy in the shaded systems, which can be attributed to pasture management by 95% light interception. The microclimate affected positively the productive performance of the massai grass in full sun environment, however it affected negatively the crude protein content. In the SMS, it was possible to verify that there was a balance between the production and forage quality of the massai grass, as higher massai grass productivity was obtained compared to the SIS, and higher crude protein content of the forage than in the SFS. Milk production was highly dependent on dry matter production, which is often favored in monoculture grass systems. Moderate shading promotes a balance between production and nutritional value of the massai grass as well as ambience for dairy cows at different times of the year in Brazilian tropical regions.

BANKING MEMBERS:
Externo à Instituição - MARCELO DIAS MULLER - EMBRAPA
Externo à Instituição - INÁCIO DE BARROS - EMBRAPA
Externo ao Programa - 3157825 - ADENILSON JOSE PAIVA
Externo ao Programa - 3058101 - ANDRE MORAIS MOURA
Presidente - 1322816 - CARLOS AUGUSTO BRANDAO DE CARVALHO