Wilson Zacaron’s research while affiliated with Universidade do Oeste de Santa Catarina and other places

Nosso objetivo foi determinar se a suplementação de microalgas (Schizochytrium limacinum) afeta a produção diária, composição e perfil de ácidos graxos do leite orgânico. Oito vacas em lactação foram mantidas a pasto e divididas em dois grupos: as alimentadas com sabugo de milho como suplemento duas vezes ao dia durante a ordenha (CTL) e as alimentadas com sabugo de milho misturado com 100 g de microalgas (ALG) por vaca diariamente. As microalgas não afetaram a produção e composição diária do leite, mas foi observada uma tendência de redução da gordura do leite. O nível de ácido esteárico no leite de vacas alimentadas com ALG foi significativamente reduzido em 2,46 vezes, enquanto os níveis de ácido elaídico e ácido linoléico conjugado foram significativamente elevados em 3,3 vezes e 1,8 vezes, respectivamente. Uma proporção significativamente maior de PUFA: MUFA foi observada no tratamento com ALG, enquanto a proporção de MUFA: ácido graxo saturado mostrou uma tendência a aumentar (P = 0,073). Microalgas ricas em ácidos graxos ômega-3 enriquecem com sucesso o leite orgânico sem afetar negativamente a produtividade ou composição. Os consumidores podem ser atraídos para aumentar a ingestão de gordura polinsaturada ômega 3 do leite orgânico. Esses resultados podem apoiar a decisão de nutricionistas e agricultores de alimentar o gado leiteiro com microalgas, uma vez que é economicamente viável.

Dry ground corn kernels are widely used as sources of energy readily available for microbial synthesis in the rumen. The objective of the present study was to measure the effect of particle size on the storage length of rehydrated and ensiled corn grain. Commercial corn was milled in 2-, 4-, 6-, 8-, and 10-mm sieves, rehydrated until reaching 65% DM, and ensiled for 14, 28, and 56 days, in a completely randomized design with a 5 x 3 factorial arrangement, with six replications per treatment. PVC mini-silos were used, with dimensions of 25 cm height x 10 cm of diameter. The variables DM, MM, CP, NDF, ADF, pH, molds and yeasts count, fermentative losses, in vitro degradability and aerobic stability were subjected to analysis of variance. The Tukey test was used to compare means. LAB counts was subjected to Wilcoxon's non-parametric test, considering significance at p < 0.05. Rehydrated corn silages with smaller particles (2 and 4 mm) showed higher LAB and mold counts, higher levels of CP and EE and higher density at opening silos than that of coarser particles. However, they showed lower percentages of DM, and were susceptible to microbial attack and faster temperature increases than were coarse particles during the chosen storage times. Silage subjected to 56 days of fermentation showed lower contents of NDF, ADF and CP, lower gas losses and lower pH values in aerobiosis, and increased levels of soluble protein (A + B1 fractions), losses by effluents, number of hours to reach maximum temperature, and time to break aerobic stability. Coarse-grind silages subjected to 56 days of storage showed better chemical composition, lower LAB and mold counts, and less susceptibility to microbial degradation when exposed to air.

The objective of this study was to evaluated fermentation losses and silage quality with the addition of different by-products in TMR. A completely randomized design was used with four treatments: Control (CTL, with hay, corn silage, cracked corn, soybean meal, wheat bran and minerals); CTL plus the addition of fresh orange pulp (FOP); CTL plus soybean hulls (SBH) or CTL plus wet brewery wastes (WBW), with six replicates. The ingredients were mixed and ensiled in 24 PVC experimental silos. After 56 days of ensiling, fermentation losses (effluents, dry matter and gases), and the TMR silage pH and chemical composition were analyzed; aerobic stability was evaluated over seven days after the silos were opened. Lower dry matter (P ? 0.0001) was observed in TMR ensiled with wet (WBW and FOP) compared to dry (SBH) by-products. Greater ADF (P = 0.031) was observed in SBH when compared to others by-products. WBW and FOP increased dry matter (P ? 0.0001) and effluent losses (P ? 0.0001) when compared to CTL and SBH. SBH treatment remained stable after 176-hour, which differ (P = 0.0015) compared with the other treatments (range from 94.5 to 99 hours of exposure to air). The density (kg DM/m3) changed (P ? 0.0001) among treatments. The inclusion of SBH in TMR silages had the greatest density, followed by CTL, WBW and FOP. The density was negatively correlated with DM losses ( r= - 0,81; P ? 0.0001). The pH differ (P = 0.003) among treatments. Highest pH of TMR silage was observed for SBH (3,67) and the lowest (3,56) for FOP. Soybean hulls successful improved aerobic stability and density, whereas aerobic stability and density were decreased and fermentation losses increased when fresh orange pulp and wet brewery were used. Little effects on chemical composition were observed, thereby agro-industrial by-products can be used in TMR silages as long as there is adequate product availability and pricing.