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Made available in DSpace on 2022-04-28T19:48:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Yeast products (live yeast, yeast cell wall, yeast culture) have been added to the diet of beef cattle under conditions that characterize stress, such as receiving period, high-concentrate finishing diet, periods of elevated ambient temperature, with variable responses in animal performance, health and physiological parameters. Therefore, we conducted a meta-analysis to examine the yeast product's effects on performance parameters, health, and physiological responses of beef cattle. Studies that met the selection criteria included 27 articles. Twenty-seven studies with up to 119 treatments means were included in the data set. The magnitude of the effect (effect size) was assessed using weighted mean differences (WMD) for continuous results, between the yeast products addition and control treatments. The binary results (health parameters) were examined using risk ratio (RR). Heterogeneity was explored by meta-regression and subgroup analysis. The addition of yeast products increased (P ≤ 0.04) animal performance with increase in dry matter intake (DMI; WMD = 0.083 kg/d), average daily gain (ADG; WMD = 0.036 kg/d), final body weight (WMD = 3.75 kg), and feed efficiency (WMD = 2.08 g/kg). In the current study, most of the responses had low heterogeneity (I2 < 25%), which means low inconsistency in the effect size estimates and independent response from the possible sources of heterogeneity included. Yeast products increased (P ≤ 0.02) the digestibility of dry matter (WMD = 11.84 g/kg), organic matter, (WMD = 15.88 g/kg), crude protein (WMD = 26.99 g/kg), neutral detergent fiber (WMD = 36.84 g/kg) and, increased the average ruminal pH (WMD = 0.088), enabling a reduction in the risk ratio of severely abscessed occurrence (RR = 0.41). In blood parameters, yeast products decreased glucose (P < 0.01; WMD = −5.47 mg/dL) and increased (P ≤ 0.04) urea (WMD = 1.59 mg/dL) and non-esterified fatty acid (WMD = 0.006 mM) concentrations. The acute-phases protein concentrations (Amyloid A, WMD = 3.79 μg/mL and lipopolysaccharide-binding protein WMD = 11.01 μg/mL) were also increased (P = 0.01) when the yeast product was fed. On the other hand, the risk ratio of occurrence of morbidity and mortality were similar (P ≥ 0.49; RR = 0.94 and 0.77 respectively). This meta-analysis indicated that yeast products increased animal performance, and the benefits can be attributed to better rumen health and increases in nutrient digestibility. São Paulo State University (UNESP) - Faculdade de Ciências Agrárias e Veterinárias (FCAV) Agência Paulista de Tecnologia dos Agronegócios (APTA) Professor of the graduate program in Animal Science at São Paulo State University (UNESP) and Researcher at Agência Paulista de Tecnologia dos Agronegócios (APTA) São Paulo State University (UNESP) - Faculdade de Ciências Agrárias e Veterinárias (FCAV) Professor of the graduate program in Animal Science at São Paulo State University (UNESP) and Researcher at Agência Paulista de Tecnologia dos Agronegócios (APTA) CNPq: 141577/2020-7 FAPESP: 2018/20176–0

Objetivou-se com este trabalho avaliar o efeito da adição de cal virgem e dos tempos após a aplicação sobre a estabilidade aeróbia e o crescimento de microrganismos (leveduras e fungos) na cana-de-açúcar in natura. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições. Avaliaram-se a estabilidade aeróbia (temperatura), a dinâmica de desenvolvimento de leveduras e fungos e o pH, em um esquema de parcelas subdivididas, com cinco doses de cal (0; 0,5; 1,0; 1,5 e 2,0%) e cinco tempos após aplicação (0, 24, 48, 72, 96 horas). Houve efeito significativo das doses de cal para todos os parâmetros avaliados. A cana que não foi tratada com cal (0%) apresentou quebra da estabilidade no menor intervalo de tempo. Os valores de pH aumentaram gradativamente de acordo com a dose de cal aplicada e diminuíram com o tempo após aplicação. Houve aumento numérico na contagem de leveduras até as 72 horas após a aplicação da cal, independentemente da dose, e os valores tenderam a estabilizar no tempo de 96 horas pós-tratamento. Não houve efeito significativo das doses de cal sobre o desenvolvimento dos fungos. A aplicação de cal virgem é eficaz no controle do crescimento de leveduras e aumenta a estabilidade aeróbia da cana-de-açúcar in natura.The objective of this work was to evaluate the effect of whitewash addition and the times after application on aerobic stability and growth of microorganisms (fungi and yeasts) in fresh sugarcane. It was used a completely randomized experimental design, with four replications. Aerobic stability (temperature) and the concentrations of yeast and fungus and pH were evaluated in a split-splot scheme with five doses of whitewash (0; 0.5; 1.0; 1.5 and 2.0%) and five times after treatment (0, 24, 48, 72 and 96 hours). There was a significant effect of doses of whitewash for all evaluated parameters. The sugarcane which was not treated with whitewash (0.0%) showed a break in stability at the shortest time interval. The pH values increased gradually according to the dose of whitewash applied and they decreased over time. There was a numerical increase on the counting of yeast until 72 hours after application of whitewash, regardless to the dose, and the values tended to stabilize in 96 hours after treatment. There was no significant effect of whitewash doses on fungi development. The use of whitewash is effective in yeast growth control and it also promotes aerobic stability in fresh sugar cane.

Avaliou-se a degradação da matéria seca (MS), da proteína bruta (PB), da fibra em detergente neutro (FDN), da fibra em detergente ácido (FDA) e da hemicelulose das silagens de milho, de sorgo e de Brachiaria brizantha. Foram utilizados três novilhos Nelore, machos, fistulados no rúmen, com média de peso de 200kg. Em cada animal foram incubadas amostras das três silagens nos tempos de 0, 6, 12, 24, 36, 48, 72 e 96 horas. Para as degradabilidades potencial e efetiva da MS (taxa de passagem no rúmen de 5%/h), a silagem de milho foi a que apresentou valores mais altos, 80,1 e 56,7%, respectivamente, seguida da silagem de sorgo, 73,0 e 45,3%, e da silagem de Brachiaria, 60,8 e 33,7%. Para a PB, o maior valor de degradabilidade foi verificado para a silagem de milho, 87,0%, seguida das silagens de sorgo, 81,8%, e de Brachiaria, 75,2%. A degradabilidade da FDN foi maior para as silagens de milho e sorgo. Para FDA, a silagem de sorgo apresentou perfil de degradação menor que a silagem de milho. Os resultados sugerem melhor qualidade da silagem de milho, seguida pela do sorgo e pela de Brachiaria.The experiment evaluated the degradation of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and hemicellulose of silages of corn, sorghum and Brachiaria brizantha. Three steers averaging 200kg bw were rumen fistulated. In each animal, the three silages were incubated for 0, 6, 12, 24, 36, 48, 72, and 96 hours. For the potential degradability and the effective degradability (passage rate 5%/h) the corn silage presented the highest values, 80.1 and 56.7%, respectively, followed by the sorghum silage (73.0 and 45.3%), and the Brachiaria silage (60.8 and 33.7%). For CP, the highest degradability value was also verified for the corn silage (87.0%), followed by the sorghum silage (81.8%), and Brachiaria silage (75.2%). For NDF, the highest degradability values were also verified for the corn and sorghum silages. However, for ADF, the sorghum silage presented degradation profile lower than the corn silage. The results suggest a better quality of the corn silage, followed by sorghum and Brachiaria silages.