Experimental Silos Research Articles

Effects of chemical and microbial additives on clostridium development in sugarcane (Saccharum officinarum L.) ensiled with lime

AbstractThe aim of this study was to compare strategies to prevent clostridium growth in sugarcane silages added with lime. In Experiment 1, treatments were (as fed basis): no additives (Control), 15 g lime kg−1 (L), 15 g lime kg−1 + 1.5 g sodium benzoate kg−1 (L+B), 15 g lime kg−1 + 0.7 g sodium nitrite kg−1 (L+N), 15 g lime kg−1 + Lactobacillus buchneri (5 × 105 cfu g−1) (L+LB) and 15 g lime kg−1 + Lactobacillus plantarum (5 × 105 cfu g−1) (L+LP). Plastic buckets (20 L) were used as experimental silos. Silage fermentative losses and aerobic stability were also evaluated. Lime treatment was not effective in decreasing dry matter (DM) losses compared with control silage (121 and 158 g kg−1, respectively). On the other hand, L+LB, L+B, L+LP and L+N treatments significantly decreased DM losses (70, 73, 87 and 98 g kg−1, respectively). The aerobic stability of silages L (172 h), L+B (155 h) and L+N (223 h) was substantially higher compared to those treated with L+LB (49 h), L+LP (48 h) and control (52 h). Control silages had low counts of clostridia (log 3.3 cfu g−1) whereas L and L+LB treated silages reached very high clostridium counts (log 6.7 and log 6.0 cfu g−1, respectively). The remaining treatments resulted in intermediate values. In Experiment 2, sugarcane treated with lime (15 g kg−1) received the following doses of sodium nitrite prior to ensiling: 0, 0.5, 1.0 and 1.5 g kg−1 as fed. Treatments did not affect clostridium counts but decreased butyric acid and 2,3‐butanediol. The silage with the highest nitrite dose decreased the butyric acid content substantially compared to other treatments but the final level (5.9 g kg−1 DM) was above the target value for well‐fermented silage. None of additives combined with lime were able to provide completely butyric acid free silages.

Chemical composition of elephant grass silages supplemented with different levels of dehydrated cashew bagasse

The objective of the present study was to evaluate the chemical composition of elephant grass silages supplemented with different levels dried cashew bagasse (DCB). Our experiment used a randomized design replicated four times, each replicate consisting of the following five treatments: 100% elephant grass; 95% elephant grass + 5% DCB; 90% elephant grass + 10% DCB; 85% elephant grass + 15% DCB; and 80% elephant grass + 20% DCB. The elephant grass was cut manually to a residual height of 5 cm at 80 days of age, and cashew bagasse was obtained from the processing of cashew stalks used in fruit pulp manufacturing in Mossoró/RN. Plastic buckets were used as experimental silos, and 90 days after ensiling the experimental silos were opened and the contents analyzed. The addition of dried cashew bagasse to silage linearly increased the levels of dried matter and crude protein by 0.59% and 0.13%, respectively, for each 1% addition (P < 0.05). The neutral detergent fiber and acid detergent content of the silages was reduced by 0.22% and 0.09%, respectively, for each 1% addition of the bagasse. The total carbohydrate content was not influenced by the bagasse addition (P > 0.05), and averaged 82.29%. The levels of non-fiber carbohydrate showed linear growth (P < 0.05) as the dehydrated cashew bagasse was added, and pH and ammoniacal nitrogen levels were reduced. The addition of the dehydrated bagasse to elephant grass silage improves its chemical composition, and it can be effectively added up to the level of 20%.

Changes in the nutritive value and aerobic stability of corn silages inoculated with Bacillus subtilis alone or combined with Lactobacillus plantarum

Chemical composition, fermentation characteristics, in vitro digestibility and aerobic stability were evaluated in corn silage inoculated with microbial additives in two different experiments. Inoculant treatments (untreated, Bacillus subtilis and B. subtilis combined with Lactobacillus plantarum) were applied to fresh forages. Chopped corn plants (2B655 Hx) were ensiled in laboratory silos for periods of 7, 14, 21 and 63 days to evaluate the fermentation parameters. The experimental silos were weighed to determine gas losses. After the ensiling period, the silage was sampled to determine chemical composition and in vitro organic matter digestibility. To evaluate aerobic stability, chopped corn plants (AG‐1051) were ensiled in laboratory silos that were opened after 96 days of ensiling. The silage was placed in different buckets containing data loggers. The silage was sampled after 0, 4, 8 and 12 days of exposure to air to evaluate the microbial populations and pH. The data were analysed as a completely randomised design using a mixed repeated-measures model in the MIXED procedure of SAS. To evaluate each treatment relative to the fermentation times, a regression analysis using the PROC REG procedure of SAS was applied. A significance level of P < 0.05 was used. Inoculation with both strains increased lactic acid concentration, whereas the use of B. subtilis alone or combined with L. plantarum improved in vitro apparent organic matter digestibility. In the B. subtilis and B. subtilis combined with L. plantarum silages, moulds and yeasts decreased, and aerobic stability was improved. Inoculation with B. subtilis alone or combined with L. plantarum improved the nutritional value and aerobic stability of corn silage.

Composição nutricional de milho Bt ensilado com inoculante enzimobacteriano e avaliado em ovinos

O objetivo foi avaliar as características agronômicas e químico-bromatológicas de dois híbridos de milho Bt (30F35H e CD397YH) ensilados com inoculante enzimobacteriano. Os teores de FDN foram semelhantes para todas as frações de planta, já o teor de FDA diferiu quanto à planta inteira e colmo, enquanto a lignina diferiu em relação à planta inteira, colmo e sabugo. A DIVMS não apresentou diferença entre os híbridos em nenhuma das frações. As silagens foram produzidas em silos experimentais (aproximadamente 200kg). As concentrações de MS, EE, FDN, NDT e DIVMS não mostraram diferença entre as silagens dos híbridos avaliados. Já os teores de MM, PB, FDA e lignina diferiram. Não houve diferença entre as silagens dos híbridos para os valores de NDT estimado e para a DIVMS. Também não foi observado efeito do inoculante sobre os valores de CHT, CNF, FDN e DIVMS. Conclui-se que o híbrido Pioneer foi superior ao Coodetec em produtividade de MV ha-1, porém a composição nutricional das silagens não diferiu na concentração de NDT e digestibilidade avaliadas em ovinos. Não houve efeito do uso de inoculante na digestibilidade da matéria seca e da fração fibra em detergente neutro das silagens.

Dinâmica química, microbiológica e física da silagem de farelo úmido de glúten de milho

Objetivou-se avaliar aspectos físico-químicos e microbiológicos do farelo úmido de glúten de milho (FUGM) em função do tempo de ensilagem. O FUGM foi avaliado em silos experimentais e, nos dias um, três, sete, 14, 21, 28 e 42, foram realizadas as avaliações físicas, químicas e microbiológicas da silagem. O delineamento experimental foi inteiramente casualizado com quatro repetições e obtidas equações de regressão em função do tempo. O tempo de ensilagem não afetou (P>0,05) o percentual de fibra em detergente neutro, fibra em detergente ácido, proteína bruta, matéria mineral, extrativos não-nitrogenados, nutrientes digestíveis totais e contagem de clostrídios. Os teores de matéria seca, extrato etéreo, perdas por efluentes, perdas por gases e população de bactérias láticas variaram entre 46,54 e 49,05%; 0,96 e 1,71%; 17,97 e 35,14g kg-1; 1,90 e 5,68% e 5,0 e 6,9log UFCg-1 de silagem, respectivamente, todos com equações com r2≤0,6.O pH (Y=4,12926-0,00894dias+0,00024126dias2,r2=0,75) e a temperatura (Y=19,82657+0,11734dias-0,00502dias2,r2=0,73) tiveram seus menores e maiores valores, respectivamente, em 18,5 e 11,7 dias. A contagem de bolores e leveduras sofreu redução em função do tempo de ensilagem (Y=6,8983-0,0363dias,r2=0,84). A ensilagem permite eficiente conservação dos aspectos químicos, microbiológicos e físicos do FUGM até 42 dias de ensilagem

Efeito da inclusão de polpa cítrica na ensilagem de capim-xaraés

The objective of this study was to evaluate the effect of inclusion of different levels of pelleted citrus pulp (PCP) on the quality of xaraes grass silage. Xaraes grass was ensiled at 54 days of growth with 0, 10, 20 and 30% PCP and divided into 20 experimental silos (five repetitions/treatment). A completely randomized design was adopted. The silos were opened after 67 days for the determination of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), pH, and titratable acidity of the silages. The inclusion of PCP did not influence DM content, but reduced CP content. NDF and ADF content decreased with the addition of citrus pulp. Regarding pH, a significant difference was only observed for the inclusion of 30% PCP. Titratable acidity in the silage was lower in the absence of PCP (0%) compared to the treatment with 30% (P<0.05). The inclusion of 30% PCP in xaraes grass silage is indicated since it improves the quality of the fibrous fraction, while maintaining acceptable pH values.

Modification of Lipid Fraction in Ensiled High Moisture Corn

The aim of this work is to study the changes of the lipidic fraction of ensiled high moisture corn (HMC). 11 maize hybrids were used, ensiled each in 3 mini experimental silos of 100 litres. For each hybrid 1 sample of fresh high moisture corn was obtained immediately after milling and 3 samples of ensiling HMC were kept after 2, 7 and 12 months. All samples were analysed for pH, dry matter, lactic acid, ammonia-N, ether extract, fatty acid composition and volatile fatty acids (VFAs). Ether extract of fresh high moisture corn was 35.7 g/kg dry matter (DM) and increased after 2 and 7 months of storage up to 39.4 g/Kg DM (P≤0.01); after 12 months it decreased to 38.1 g/kg DM (P≤0.01). Both saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) percentages decreased from 18.23% to 15.47% and from 24.84% to 23.57% respectively (before ensiling vs 12 months P≤0.01). Linoleic acid percentage increased from 55.34% to 59.44% (before ensiling vs 12 months P≤0.01). The linoleic acid content (g/kg of DM) increased on average from 19,1 before ensiling to 22.5 after 12 months of ensiling. These differences may affect the linoleic acid content of heavy pig diets when maize is used as HMC instead of corn meal.

Nutritional value of ensiled grocery food waste for cattle.

Assessment of nutrient variability, feed value, ensiling capability, intake, and digestibility of grocery food waste recycled from large retail stores was conducted in 3 experiments. In Exp. 1, 115 proximate nutrient analyses of grocery byproduct feed (GBP) from stores in the southern United States from April 8, 2011, to November 18, 2012, were evaluated for variation in nutrient concentration. Grocery byproduct feed was characterized as being a readily fermentable, high-moisture energy feed with an average DM content of 17.5 ± 3.7% and TDN of 89.8 ± 7.1%. In Exp. 2 and 3, grocery food waste consisting of fruit, vegetables, and bakery items from large retail stores in the Atlanta, GA, area was used for ensiling and feeding studies. The GBP material for Exp. 2 was processed on farm into homogenous slurry and treated to reduce its moisture content and preserved in experimental silos. Drying treatments included 3 levels of citrus pulp substitution (8, 16, and 24% as-fed basis), or passively removing liquid as seepage after stacking for 24 h, or oven drying (24 h at 80°C). All GBP mixtures effectively ensiled after 28 d, as determined by changes in pH, soluble carbohydrates, and fermentation acids. Ensiled GBP was moderately stable during 72-h aerobic exposure. In Exp. 3, a feeding/digestibility trial, 8 yearling Holstein steers were used in a replicated 4 × 4 Latin Square and fed 4 incremental levels of ensiled GBP in total mixed rations (TMR). Steers were fed 0, 18, 36, and 54% ensiled GBP as part of a TMR containing 68% wheat silage and 32% concentrate on a DM basis. The rations averaged 35.9, 30.7, 26.8, and 23.8% DM with incremental levels of GBP. Steers increased DM intake and digestibility when fed increasing GBP (P < 0.5). Digestible energy and TDN were linearly related to the level of GBP fed (P < 0.01). The TDN content of GBP was 82.7% (DM basis) and similar to predicted TDN values from commercial feed analyses of GBP. The feeding and nutritive value of ensiled GBP indicates it can be priced to be used effectively as an energy supplement in TMR for cattle.

Losses through gases and effluent and nutritional value of Brachiaria decumbens with addition of soybean hulls

The objective of this experiment was to evaluate the losses of nutrient through gases and effluents, the nutrient recovery, fermentation parameters and the chemical parameters of silages of Brachiaria decumbens with the addition of soybean hulls, testing five levels of inclusion: 0, 10, 20, 30 and 40% (as is), with five replications per treatment. After the standardization cut of the forage, performed at 5 cm from the soil level, the soil was fertilized with nitrogen and potassium in the form of ammonium sulfate and potassium chloride, respectively, at 60 kg/ha. After 60 days, the grass was cut at 10 cm from the soil and ensiled. Experimental silos with capacity of 10 liters with Bunsen valve were used. Silos had 3 kg of sand conditioned at the bottom for retention of the effluents. The results show that the contents of dry matter, crude protein, acid detergent insoluble fiber and total digestible nutrients presented positive linear behavior with the inclusion of soybean hulls. In the grass silages with addition of soybean hulls, there was greater recovery of dry matter in relation to the control silage, which is a reflection of the negative linear behavior for the values of losses of gases and effluent. There was quadratic behavior in the pH values and negative linear behavior for the ammonia N values and buffering capacity with the inclusion of the additive in the grass silage. Inclusion of soybean hulls is sufficient to improve the fermentation pattern and minimize the losses through gases and effluents, contributing to the nutrient recovery, in addition to promoting overall improvement of the nutritional value of Brachiaria grass silages.

Aerobic stability of sugar‐cane silage inoculated with tropical strains of lactic acid bacteria

AbstractAerobic stability is an important feature in the evaluation of silages. The aims were to investigate the chemical and microbiological changes that occur in sugar‐cane (Saccharum spp.) silage after aerobic exposure, to identify the major species of yeasts associated with the aerobic deterioration process and to select lactic acid bacteria (LAB) strains that can improve the aerobic stability of this silage. Fourteen wild LAB strains belonging to Lactobacillus plantarum, L. brevis and L. hilgardii were evaluated using experimental silos. Silage samples were collected at 0, 96 and 216 h after aerobic exposure to determinate the DM, WSC, pH, products of fermentation, to evaluate the silage temperatures and to identify yeast species associated with the aerobic deterioration of silage. The strains tested were able to modify the fermentative and chemical parameters and the diversity of yeasts species of silage after aerobic exposure. There was no association between the facultative or obligatory heterofermentative fermentation patterns and the increased aerobic stability of silage. Aerobic stability of sugar‐cane silages was associated with high acetic acid and 1,2‐propanediol concentrations. L. hilgardii UFLA SIL51 and UFLA SIL52 strains promoted an increase in aerobic stability of silage.

Use of additives and pre-wilting in Tifton 85 bermudagrass silage production

The use of tropical grasses silage has become common in ruminant feed. An experiment was conducted to evaluate the fermentation characteristics, nutritional value, pH, fermentative capacity, ammonia nitrogen / total nitrogen (NH3N/total N) of Tifton 85 bermudagrass grass silage with different additives and wilting. The treatments were: pre-drying in the sun for two hours before silage, use of inoculant-enzymatic addition of soybean hulls, corn grits addition and use of salt in the surface layer of the silo. The experimental design was completely randomized with 6 treatments and 4 replications. Plants of Tifton 85 bermudagrass with 38 days of growth were ensiled in experimental silos with Bunsen valve type with packing densities of 236 kg of silage per m³ for Tifton 85 bermudagrass pre-dried in the sun and 294 kg of silage per m³ for the other treatments. The proportions of soybean hulls and corn grits added to the silage were calculated based on the initial DM content of Tifton 85 bermudagrass order to obtain MS 320 g kg-1 for the material to be ensiled. The buffering capacity did not differ between treatments in getting 29.56 (meqHCl/100gMS). It was found that the concentration of ammonia nitrogen did not differ between silages and remained low (3.22 g kg-1), the pH after silo opening was also similar with an average of 4.09 getting above 4.2 only in Tifton 85 bermudagrass silage without pre-treatment. The crude protein was higher in silages Tifton 85 bermudagrass and Tifton 85 bermudagrass with soybean hulls (17.48 g kg-1). The use corn grits caused a reduction in the values of NDF. The use of salt on the surface the layer reduced the production of latic and acetic acid.

Cinética de fermentação ruminal in vitro, composição química e perfil de ácidos graxos da silagem de bagaço de laranja com fubá de milho

The objective of this study was to evaluate the effects of corn meal in silage orange peel in natura. The experiment has adopted a completely randomized, with four treatments (corn meal levels) and four replications. There were used experimental silos made of bucket of 12 L. Silos were opened at 90 days after ensiling, and evaluated the gases and effluent losses, pH, chemical composition, volatile fatty acids (acetic, propionic, butyric, valeric, isovaleric), and in vitro gas production. The dry matter (DM), ether extract (EE), non-fiber carbohydrates (NFC), and organic matter showed a linear increase with the inclusion of corn meal. The contents of neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude protein (CP) decreased with increasing proportion of corn meal. Regarding the rumen fermentation kinetics there was a quadratic effect of increasing inclusion of corn meal in the final volume of gas from the non-fiber carbohydrates (VfCNF) and quadratic effect in decreasing total gas production of the fiber (VfCF). The orange peel can be conserved as silage with the inclusion of corn meal, allowing satisfactory pH levels and minimize effluent losses, ensuring good preservation of the silage. The levels of 8 and 12% were the most efficient, ensuring higher levels of DM, lower levels of NDF and ADF, higher levels of NFC, higher production volume of gas, which can be considered a suitable source of forage for ruminants in general.

Efeito de aditivos na composição bromatológica e qualidade de silagens de coproduto do desfibramento do sisal

Fermentation profile and nutritional value of sisal co-product silage (SC) subjected to seven treatments (additives), were evaluated. The SC was ensiled in natura and added with: soy meal, urea, wheat meal, palm kernel cake, A. sisalana dust, licuri cake and cottonseed cake. Experimental silos with capacity for approximately 15 kg of silage, were used. The silos were opened 60 days after ensilage process. It was used a completely randomized design with three replications. The SC in natura present low values of dry mater (DM) 12.3% and the additives increased dry matter silages, exception for urea. The SC silage additivated with soybean meal (pH 4.9) and palm kernel cake (butyric acid = 0.07% DM) differed, respectively, for pH and butyric acid, compared with in natura SC silage (pH = 4.1 and butyric acid = 0.03% DM). The addition of soybean meal, urea, cottonseed meal, wheat bran and palm kernel, increased crude protein (CP) of in natura SC silage. The NDF in silage increased with addition of cottonseed meal or palm kernel cake (60.1 and 66.2% DM) in relation in natura SC silage (42.9% DM). The in natura and additivated silages of SC were considered as good or excellent quality.

Selection of tropical lactic acid bacteria for enhancing the quality of maize silage

The objective of this study was to select lactic acid bacteria (LAB) strains isolated from silage and assess their effect on the quality of maize silage. The LAB strains were inoculated into aqueous extract obtained from maize to evaluate their production of metabolites and pH reduction. The ability to inhibit the pathogenic and silage-spoilage microorganisms’ growth was evaluated. Nine LAB strains that showed the best results were assessed in polyvinyl chloride experimental silos. The inoculation of the LAB strains influenced the concentration of lactic and acetic acids and the diversity of Listeria. The inoculation of silages with Lactobacillus buchneri (UFLA SLM11 and UFLA SLM103 strains) resulted in silages with greater LAB populations and improvements after aerobic exposure. The UFLA SLM11 and SLM103 strains identified as L. buchneri showed to be promising in the treatment of maize silage.

&lt;b&gt;Mesquite pod meal in elephant grass silages&lt;/b&gt; - doi: 10.4025/actascianimsci.v35i3.12506

This study evaluated the chemical composition and in vitro dry matter digestibility (IVDMD) of elephant grass silages at different growth stages (70, 90 and 110 days), with the addition (0, 5, 10 and 15%, on a fresh matter basis) of mesquite pod meal. A completely randomized design (CRD) was used in a factorial arrangement with four replications. PVC pipes 100 mm in diameter were used as experimental silos. After 30 days of ensilage, samples were taken from the open silos to determine chemical composition and IVDMD. The inclusion of mesquite pod meal (MPM) increased (p &lt; 0.01) the concentrations of DM and CP. No interaction (p &gt; 0.01) was detected between MPM concentrations and elephant grass cutting age for DM, CP and NDF contents in the silages. A decrease (p &lt; 0.01) was observed in NDF, ADF and MM concentrations with the inclusion of MPM. There was a linear increase (p &lt; 0.01) in IVDMD with increasing levels of MPM; and IVDMD decreased (p &lt; 0.01) with increasing cutting age of the elephant grass. The inclusion of mesquite pod meal contributed to improve the chemical composition and digestibility of silages.

Microbiological profile and aerobic stability of Tifton 85 bermudagrass silage with different additives

The objective of this study was to evaluate the microbiological profile and aerobic stability of silage with Tifton 85 bermudagrass and different additives and wilting. The studied treatments were: pre-drying in the sun for two hours before ensiling; use of bacterial-enzymatic inoculant; addition of soybean peel; addition of corn grits and use of salt in the surface layer of the silo. The experimental design was completely randomized with six treatments and four replications. Plants of Tifton 85 bermudagrass with 38 days were ensiled in experimental silos with Bunsen valves, with compacting density of 236 kg silage per m³ for Tifton 85 bermudagrass, which was pre-dried in the sun; the average silage was 294 kg m-3 for the other treatments. The ratios between soybean hulls and corn grits, added to the silage, were calculated based on the initial DM content from Tifton 85 bermudagrass in order to obtain 320 g/kg DM of the material to be ensiled. There was an increase of lactic bacteria and Clostridium as well as an absence of enterobacteria after the silo opening. Fungi developed only in Tifton 85 bermudagrass and its treatments before the ensilage and yeasts developed in silages of Tifton 85 bermudagrass when they received soybean hulls or corn grits after silo opening. There was no breach regarding aerobic stability of silages during the studied period. The pH reached the highest values within 48 hours after opening the silos, but there were variations during this period.

Chemical changes in sunflower silage associated with different additives

Thirty-six experimental silos arranged in a completely randomized 4 x 3 factorial design were provided to evaluate the chemical changes of sunflower silage treated with soybean hulls, sunflower crushed and urea at 14, 21 and 28 days of ensilage. The additives were based on 5% natural matter, whereas control consisted of silage with 100% sunflower plant. OM, NDIP, and MM had average rates 911.2; 86.6 and 92.9 g kg -1 of dry matter respectively. The addition of soybean hulls and sunflower crushed increased DM rates after 28 and 21 days. Urea increased nitrogen fractions and the addition of soybean hulls increased total carbohydrate content of silage by 5.1%, whereas the addition of sunflower crushed decreased the same by 2.18%. NDF, ADF and hemicellulose average rates were 625.4, 460.3 and 165.2 g kg -1 of DM. The addition of soybean hulls and sunflower crushed reduced the in vitro dry matter digestibility by 8.3 and 5.97%. The addition of 5% sunflower crushed and soybean hulls improved the nutritional value of sunflower silage and the addition of urea improved the protein rates.

Peanut cake concentrations in massai grass silage

ABSTRACTObjective. This experiment was conducted to evaluate the best concentration of peanut cake in the ensiling of massai grass of the chemical-bromatological composition, fermentative characteristics, forage value rate, ingestion estimates, and digestibility of dry matter in the silage. Materials and methods. The experiment was carried out at the Experimental Farm of São Gonçalo dos Campos at the Federal University of Bahia, Brazil. The treatments consisted of massai grass that was cut at 40 days and dehydrated, in addition to 0%, 8%, 16%, and 24% peanut cake in the fresh matter and treatment without cake. The material was compressed in experimental silos (7 liter) that were opened after 76 days. Results. The addition of 8-24% peanut cake improved the silage’s chemical-bromatological parameters, increased the dry matter and non-fiber carbohydrates and reduced the fibrous components. There was a linear increase in the estimated values of digestibility and the ingestion of dry matter depending on the levels of peanut cake in the silage. There was an improvement in the fermentative characteristics, with a quadratic effect positive for levels of ammoniacal nitrogen. The forage value rate increased linearly with the inclusion of peanut cake. Conclusions. The inclusion of up to 24% peanut cake during ensiling of massai grass increases the nutritive value of silage and improves fermentation characteristics.

Silagem da ponta de cana-de-açúcar com resíduos da agroindústria da mandioca

O trabalho teve como objetivo determinar os efeitos da adição dos níveis de 0, 5, 10, 15, e 20% na matéria natural, de casca de mandioca seca ao sol ou do farelo de varredura de mandioca sobre o valor nutricional da silagem de ponta de cana-de-açúcar. Para tal foram utilizados 36 silos experimentais pesados ao fechamento e após 60 dias de fermentação, antes da abertura para obtenção das perdas gasosas e por efluentes. Foram feitas amostragens para determinação dos valores de pH e composição química. Valores de matéria seca, proteína bruta, fibra em detergente neutro, fibra em detergente ácido, matéria mineral e nutrientes digestíveis totais foram determinados. Houve diferenças entre as silagens para todas as variáveis, com exceção da proteína bruta, na utilização da casca ou farelo de varredura de mandioca. Os valores de pH e produção de efluentes não foram influenciados pelo uso dos resíduos, já as perdas gasosas foram menores quando foi adicionada a casca de mandioca. Para melhorar a qualidade das silagens de ponta de cana-de-açúcar recomenda-se o uso de casca de mandioca seca ao sol ou de farelo de varredura de mandioca, ao nível de 20% na matéria natural, no ato da ensilagem.

Inoculação de silagens de grãos úmidos de milho, em diferentes processamentos

Objetivou-se avaliar os parâmetros fermentativos, a composição química e a digestibilidade in vitro da matéria seca (DIVMS) de silagens de grãos úmidos de milho, confeccionados com ou sem o uso de inoculante microbiano, em diferentes processamentos. No experimento 1, avaliou-se a inoculação de silagens de grãos úmidos de milho triturados, em delineamento inteiramente casualizado. No experimento 2, avaliou-se a inoculação de silagens de grãos úmidos de milho, triturados e laminados, em delineamento inteiramente casualizado, em esquema fatorial 2 x 2. O material foi ensilado em silos experimentais de PVC (50cm de comprimento e 100mm de diâmetro) e amostras foram tomadas antes e após a ensilagem. No experimento 1, a DIVMS de silagens inoculadas foi superior à de silagens controle, com médias de 80,67 e 79,80%, respectivamente. O pH, N-NH3 (% N-total) e perdas de MS não foram influenciados pela inoculação, com médias de 3,91, 1,19% N-total e 1,18% MS, respectivamente. No experimento 2, não houve influência da inoculação e do processamento sobre a DIVMS, com média de 74,59%. O pH e N-NH3 foram influenciados pela inoculação, com médias de 3,89 vs 3,94 e 0,63 vs 0,72% N-total, para silagens inoculadas e controle, respectivamente. De maneira geral, a inoculação microbiana não altera o padrão de fermentação, composição química e perdas da MS nas silagens de grãos úmidos de milho, independente do processamento. Houve melhoria de 1,09% na DIVMS de silagens inoculadas de grãos úmidos de milho.