Wilson Roberto Soares Mattos

Fermentation, losses, and aerobic stability of sugarcane silages treated with chemical or bacterial additives

Utilization of sugarcane Saccharum officinarum L. silage is increasing in Brazil but intensive ethanol production during fermentation reduces forage quality. This experiment aimed to evaluate the effects of additives on fermentation and aerobic stability of sugarcane silages produced in minisilos. Treatments were (fresh basis): untreated silage (control), urea (5.0 g kg-1), sodium benzoate (1.0 g kg-1), potassium sorbate (0.3 g kg-1), Lactobacillus plantarum (1 x 106 cfu g-1), and Lactobacillus buchneri (3.64 x 105 cfu g-1). At the 94th day after ensilage, ethanol concentration was lower in urea, benzoate, sorbate and L. buchneri supplemented silages and higher in L. plantarum inoculated silage, as compared to control. Urea and benzoate treated silages showed the highest and L. plantarum treated silage the lowest in vitro dry matter digestibility. Effluent production was higher in the urea treated silage. Inoculation with L. buchneri reduced 50% ethanol production as compared to control. Urea and L. buchneri reduced yeast count. Aerobic stability was enhanced by L. buchneri and benzoate. Sodium benzoate and L. buchneri were the most promising additives, improving both silage fermentation and aerobic stability; inoculants containing L. plantarum can be deleterious to fermentation and conservation of sugarcane silages.

Avaliação do capim-elefante (Pennisetum purpureum Schum.) cultivar taiwan A-148, ensilado com diferentes técnicas de redução de umidade

The objective of this work was to evaluate the effect of different techniques of moisture reduction on the chemical composition, in vitro deseapperance of dry matter (IVDMD) and ruminal dry matter disappearance of the elephant grass (Pennisetum purpureum Schum), cv. Taiwan A-148 silage. The treatments (A, control, B, 20, C, 30, D, 40% of corn cobs; E, wilting by 12 h, F, wilting by 24 h; G, crushing + wilting by 24 h) were allotted to a completely randomized design with three replicates. The silage treatments B and E were not efficient to reduce the excessive moisture of the forage. The wilting by 24 h increased the DM content, without affect in the CP and IVDMD. The silage treatments C and D favor the development of clostridium population, increase the concentration of NH3-N, decreased the lactic acid concentration and IVDMD of the silage. The treatment G increased the DM content and decreased the NH3-N and IVDMD. The addition of corn cobs (treatments B, C and D) decreased the ruminal DM degradation of the silage. The corn cobs decreased the moisture, but presented negative effects on the silage quality while the wilting and/or crushing are procedures that showed good results on the preservation of the ensiled material.

Efeito de aditivo químico e inoculantes microbianos na fermentação e no controle da produção de álcool em silagens de cana-de-açúcar

The objective of this study was to evaluate chemical additive and microbial inoculants effectiveness on fermentative changes that lead to the inhibition of the ethanol production and reduction of dry matter losses in sugarcane silages. Silos were made in 20 liter plastic buckets provided with a Bunsen type valve that allows gas to escape and a device to collect effluents. The applied additives were urea (1% of fresh forage); microbial additive Lalsil cana®, that has heterolactic bacteria Lactobacillus buchneri (NCIMB 40788), 3.65 × 105 CFU g-1 of fresh forage, and a non-commercial additive with homolactic bacteria Pedioccocus pentosassus and Lactobacillus buchneri (1 × 106 CFU g-1 FM) supplied by Lallemand Inc. (Montreal, Quebec). Sampling occurred after 110 days of fermentation. Urea and mainly the additive Lactobacillus buchneri and Pediococcus were efficient on the reduction of ethanol production (1.30 and 2.75% versus 8.27% in the control treatment), on the reduction of dry matter losses (47 and 60%) and soluble carbohydrates (22 and 56%), and increase in vitro dry matter digestibility (14,7 and 12,3%) when compared to the control silages, respectively. Despite the high values of acetic acid in all silages, mainly in silages inoculated with homo and heterolactic bacteria, it was not verified effects on yeast population. The silage with urea had greater values of pH and lactic acid compared to control silage. Silages with L. buchneri had, in this experiment, the largest ethanol production (11.53% vs 8.27% from control silage), resulting in greater losses and lower dry matter recovery. In addition, these silages also showed lower digestibility because of soluble carbohydrates losses and NDF accumulation, similar to the silages without additive.

Correlações simples entre as medidas de ultra-som e a composição da carcaça de bovinos jovens

The objective of this study was to evaluate correlations between ultrasonography measurements and carcass traits of 115 steers (Nellore, ½ Angus-Nellore, ½ Simmental-Nellore, and Canchim) averaging 329 kg of initial body weight and two different finishing frame sizes (small and large). After 120 days in a feedlot, body weight, rib eye area (RA), and fat thickness (FT) were measured by ultrasound. Following slaughter, carcass RA and FT measurements and weights of hindquarter, forequarter, and commercial cuts were all taken; body composition was also determined. Yields of carcass, retail cuts, and hindquarter as well as ratios of ultrasound RA per 100 kg of body weight and ultrasound RA per 100 kg of carcass weight were calculated. Data showed higher muscle deposition in ½ Simental-Nellore and Canchim and greater fat deposition in Nellore while ½ Angus-Nellore steers combined both characteristics. According to the results, RA was a good indicator of the proportion of muscle present in the carcass and selection for increasing carcass RA may decrease FT because of the negative correlation between FT and hindquarter percentage and RA. Frame size did not affect carcass composition possibly due to the small variation between both groups. Because correlations of measured and ultrasound RA and FT with carcass components yielded similar results, it was possible to validate ultrasound measurements to predict carcass composition of young bulls.

Monensina e digestibilidade aparente em ovinos alimentados com proporções de volumoso/concentrado

The response to the use of ionophores is influenced by several factors, such as the diet energetic density. The objective of this study was to evaluate the effects of monensin on total tract digestibility in ruminants fed with different diets. Eighteen wethers were randomly exposed to three diets with different concentrate levels (25%, 50% and 75%) without (control) or with monensin (40 mg/animal/day). Experimental period extended for twenty-five days, the last five used for feces and urine collection. The diet consisted of Coast-Cross hay and a concentrate mixture. Monensin increased total tract digestibility of crude protein, independent of the concentrate level (25%-concentrate: 69.6% vs. 65.3%; 50%-concentrate: 72.2% vs. 69.2%; 75%-concentrate: 73.4% vs. 69.8%). There was an interaction between concentrate level and monensin for total tract digestibility of crude fiber (25%-concentrate: 62.0% vs. 61.0%; 50%-concentrate: 53.2% vs. 59.2%; 75%-concentrate: 51.8% vs. 42.7%) and nitrogen balance (25%-concentrate: -3.8 vs. -20.6; 50%-concentrate: -10.4 vs. +2.0; 75%-concentrate: +11.4 vs. +7.9% of absorbed N). The best response to monensin was obtained for the high-concentrate diet and the worst for the 50%-concentrate. Monensin supplementation did not influence dry matter intake, total tract digestibility of dry matter, ether extract, nitrogen-free extract, acid detergent fiber, neutral detergent fiber, gross energy and total digestible nutrients in any diet. It is concluded that monensin response was greater in either high-concentrate or high-forage diets and worst in the 50%-concentrate diet.

Ultrasonography as a predicting tool for carcass traits of young bulls

Considerable resources have been allocated to support research in the development of non-invasive and non-destructive techniques for carcass composition and quality evaluation. Ultrasonography is a reliable and relatively low-cost technique that can be used. In the present study, real-time ultrasonography was used to predict ribeye area (REA) and subcutaneous fat thickness (FT) in live animals as compared to carcass measurements. Animals used were 115 yearling bull calves (initial body weight, 329 kg), kept under feedlot conditions, of four genetic groups (30, ½ Angus x Nellore; 30, ½ Canchim x Nellore; 30, ½ Simmental x Nellore, and 25 Nellore), and two finishing frame sizes (small and large). Four ultrasonographic measurements were taken every 28 days until slaughter. Predictive precision of ultrasonographic measurements increased as animals approached slaughter, reaching maximum values at the last measurement (R2=0.68 and 0.82 for REA and FT, respectively). FT carcass measurements was influenced by genetic group and live measurements (P < 0.05). Frame size did not influence REA and FT, probably due to small, but distinctive differences among genetic groups.

AVALIAÇÃO DE PRODUÇÃO E UTILIZAÇÃO DE UMA PASTAGEM DE CAPIM TOBIATÃ (Panicum maximum cv. Tobiatã) SOB PASTEJO ROTACIONADO

During the experimental period of November 1995 to April 1996 the total availability, residue left after grazing and losses of a Tobiata grass pasture were evaluated. The grazing cycle was 34 days (33 of rest and 1 day of grazing) for the main group of cows. A decrease in the grazing efficiency was observed when the cycle advanced in time and the residue height was increased. The values 68.57% and 18.82% were observed when the residue was 1491.50 and 7917.90 kg/ha during November and April respectively. The botanic composition was less desirable cycle after cycle. The steam/leaf ratio increased from 0.33 to 1.92 in November and April, respectively. The grazing pressures used for the Tobiata grass should be greater than those used in this experiment (8.84 % LW); the postgraze residue seems to be a better tool for pasture management. This practice will probably reduce losses and increase the efficiency of pasture utilization.

Efeito da adição de butirato de sódio, propionato de cálcio ou monensina sódica no concentrado inicial sobre parâmetros ruminais e de desenvolvimento do rúmen de bezerros leiteiros

O objetivo neste trabalho foi avaliar o efeito da inclusao de butirato de sodio, monensina sodica ou propionato de calcio no concentrado inicial sobre parâmetros ruminais e de desenvolvimento do trato digestorio superior de bezerros leiteiros. Quinze bezerros holandeses recem-nascidos foram fistulados no rumen e alojados em baias individuais ate a decima semana de vida, com livre acesso a agua, alimentados com leite (4 L/dia), em duas refeicoes, e concentrado a vontade contendo butirato de sodio (0,15%), monensina sodica (30 ppm) ou propionato de calcio (0,15%). A partir da quarta semana de vida dos animais, antes e 2 horas apos a alimentacao da manha, foram realizadas colheitas semanais de fluido ruminal para determinacao do pH, da concentracao de acidos graxos de cadeia curta (AGCC) e N-amoniacal. Ao completar 10 semanas, os animais foram abatidos para avaliacao do crescimento do trato digestorio superior. O pH ruminal apresentou diferencas, tanto entre horarios quanto entre os aditivos utilizados no concentrado inicial. As concentracoes de AGCC totais, bem como de cada acido graxo, nao foram afetadas pelos aditivos. Entretanto, o horario de colheita teve efeito sobre todos os parâmetros, exceto a concentracao molar de acido acetico. O peso total do trato digestorio superior, assim como o peso medio de cada compartimento e a capacidade maxima do reticulo-rumen, nao foram afetados pelos aditivos fornecidos no concentrado. Tambem nao foram observados efeitos dos aditivos sobre a altura, a largura e o numero de papilas do epitelio ruminal. A inclusao desses aditivos no concentrado inicial nao afeta os parâmetros ruminais ou de desenvolvimento do trato digestorio de bezerros em aleitamento.

Ultra-sonografia para predição da composição da carcaça de bovinos jovens

This study was conducted to evaluate the use of ultrasound measurements to predict carcass composition of 115 steers (Nellore, ½ Angus x Nellore, ½ Simental x Nellore, and Canchim) with different frame sizes (small and large) and average initial body weight of 329 kg. After 120 days in a feedlot, animals were weighed followed by ultrasound measurements of rib eye area (RA) and fat thickness (FT). Animals were slaughtered and measurements of carcass RA and FT, weights of hindquarter, forequarter, and commercial cuts, and determination of body composition were done. In addition, yields of carcass, commercial cuts, and hindquarter were calculated and no significant differences between frame sizes were found for these variables. Ultrasound measurements were not precise predicting carcass muscle content and yields of commercial cuts in this trial. However, determination coefficients from regression equations of carcass composition using ultrasound were similar and sometimes higher (e.g. bone content) than those from regression equations of carcass composition, in which measurements were taken after slaughter. Therefore, ultrasound measurements can be used to predict carcass composition of beef cattle for some variables.

Substituição parcial de silagem de milho por farelo de glúten de milho desidratado na alimentação de vacas holandesas em lactação

The objective was to study the effects of partial replacing of corn silage by corn gluten feed (CGF-21) dehydrated on milk production and composition of milk and in the blood parameters of dairy cows, beyond the economic evaluation. Inclusion levels of 0, 8 and 16% of CGF-21 (% DM) to the diets were evaluated. Thirty cows were used for study of milk production and composition and fifteen cows for blood parameters study. A 3 x 3 Latin Square experimental design with ten replications was used. There was difference among diets for milk yield and for 3.5% fat correct milk. No difference among diets was observed for the other studied characteristics. The results obtained for milk yield were: 22.44, 23.69 and 23.88 kg/anim.d and for 3.5% fat correct milk were: 23.25, 24.71 and 24.44 kg/anim.d, respectively, for the inclusionj levels of CGF-21 for the inclusion levels of 0, 8 and 16% of CGF-21 in the diet. The results obtained for the composition of milk were: percentage of fat, 3.69, 3.76 and 3.65%; milk protein, 3.22; 3.20 and 3.25%; lactose, 4.29, 4.32 and 4.31%; total solids, 12.12, 12.23 and 12.14%; N-ureic milk, 16.57, 16.50 and 14.96mg/dL, and for blood parameters were: plasma N ureic, 109.92, 21.17 and 20.21 mg/dL, seric glucose, 55.69, 56.50 and 54.78 mg/dL, respectively, for the inclusion levels of 0, 8 and 16% of CGF-21 in the diet. The diet with the inclusion of 16% of CGF-21 result on a greater profit.