Utilização do colágeno cromatado como indicador em estudos de digestão com caprinos

The objective of this research was to study the feasibility of utilizing chromated collagen as an external indicator of digestibility by comparing it to acid insoluble ash (AIA) and indigestible acid detergent fiber (IADF) as internal markers, and to the total collection method. Six castrated Alpine breed kid goats with an average weight of 33,4 kg were used. They were housed in metabolism cages. Feeding was based on 60 g/kg PV 0,75 of a pelleted ration per animal, supplied daily in two meals (7 am and 4 pm). The experimental design was completely randomized with four treatments and six replications. The results permitted the conclusion that the chromated collagen was the best of the indicators studied, and therefore, is one more indicator which can be used. The AIA and IADF were less efficient and underestimated the digestibility of the feed.

Concentrações séricas de progesterona e colesterol em cabras mestiças alimentadas com dietas hiperlipídicas no início da gestação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da silagem de grãos úmidos de milho

This work had the objective of evaluating the effects of different percentages of corn (Zea mays L.) cob on the quality of the silage of high-moisture corn grains. The following treatments were studied: percentages of corn cob in the silage (0, 5, 10, 15 and 20%); period of sampling after opening the silos (zero, two, four and six days). The factorial arrangement 5 × 4 was studied according to a completely randomized block design with three replications. The variables studied were not affected by the sampling period. The buffering capacity and the pH were not affected by the cob, while the percent soluble carbohydrates and amoniacal nitrogen increasing until 1.2 and 1.89 unit percent, respectively. Increasing the amount of corn cobs reduced the contents of DM (from 63.9% to 58.6%), CP (from 10.0% to 7.3%), EE (from 4.87% to 3.92%) and the values of DMIVD (from 90.5% to 79.1%) in the silages and increasing the contents of acid detergente fiber (ADF) (from 3.3% to 12.9%) and neutral detergente fiber (NDF) (from 15.16% to 26.1%). The values of brute energy (BE) were not affected (P>0.01) by the cob corn in the silage.

Degradabilidade ruminai da fibra em detergente neutro e do nitrogênio insolúvel em detergente neutro da silagem de milho e do farelo de soja, em bovinos da raça nelore

The nylon bag in situ degradation thecnique was employed to study the ruminai degradability of the neutral detergent fiber and neutral detergent insoluble nitrogen of the corn silage and soybean meal in four rumen fistulated Nellore steers, averaging 36 months of age and 520 kg of liveweight. A randomized completelcs block experimental design was used, where the animals constituted the blocks. It was used diets with two levels of concentrate: 20 and 40%.The forage used in the diets was corn silage, and the concentrate ingredients were: soybean meal, cottonseed meal, corn grain and sorghum grain. The NIDN degradation rate of the corn silage and the soybean meal showed a decrease of 32,1% and of 46,0 % as a function of the higher concentrate level of the diet, but the effective and potential degradability of this fraction were not affected. Concerning to the NDF, the soluble fraction, potentially degradable and undegrable , were not affected by the increase on the diet concentrate level, but for the corn silage, there were 21,8% of reduction on the effective degradability of NDF. The use of lag time promoted higher degradability values for the studied fraction. The obtained values for some evaluated parameters, different from that assumed by CNCPS, showed the necessity of more data about brazilian used feeds, for model adjustments.

Desempenho e Digestibilidade in vivo de Cordeiros Alimentados com Dietas Contendo Canola em Grão Integral em Diferentes Formas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of the diet on in situ disappearance of dry matter, organic matter, and neutral detergent fiber of hydrolysed sugar cane bagasse

The effects of two diets based on hydrolysed sugarcane bagasse (HSB) and whole cottonseed (WCS), with or without oat hay, were analyzed for the in situ disappearance of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) of HSB. Six mature castrated rams with a permanent T ruminai cannula were used in a complete randomized split plot design. The incubation times were 3, 6, 9, 12, 24, 48 and 72h. The diet with oat hay showed higher disappearance indexes for the NDF fraction. Furthermore, the maximum degradation of HSB constituents was reached around 48h of incubation. The diets were T1=64% hydrolyzed sugarcane + 36% whole cottonseed and T2=14% hydrolyzed sugarcane bagasse + 36% cottonseed + 50% oat hay.

Efeito do Tratamento com Hidróxido de Sódio sobre a Fração Fibrosa, Digestibilidade e Tanino do Feno de Jurema-Preta (Mimosa tenuiflora. Wild)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desempenho ponderal de novilhas mestiças Holandês x Zebu submetidas a duas estratégias de suplementação mineral

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparações entre equações de predição de consumo de capim-elefante cortado para vacas lactantes

This work aimed to compare intake prediction equations with values obtained by direct methods using chopped elephant-grass offered to crossbreed lactating cows with rumen canulas. The experimental design was a 3 x 3 Latin square (three animals and three cutting ages: 30, 45 and 60 days). The equations used for intake prediction (y) were: (1) y= -1.19 + 0.035(a+b) + 28.5c; (2) y= [%NDF on DM]*[NDF intake]/[(1- a - b)/KP+b/(c+kp)]/24; (3) y= -0.822 + 0.0748(a+b) + 40.7c and (4) equation 2 with values of intake measured directly. The predictions of NDF intake by equations were not different among treatments, instead of the difference among values measured directly: the 30 day-old had lower intake (5.29 kg/day) in relation to 45 (6.57 kg/day) and 60 (7.31 kg/day) day-old grasses. In general, equations overestimated the DM intake in relation to direct measuring (9.0 kg/cow/day), with exception of equation 3 which underestimated the intake (7.7 kg/day). The means of DM intake found by equations 1 and 2 (13.7 and 13.4 kg/cow/day, respectively) were similar between themselves and superior in relation to those found by equation 4 (9.7 kg/cow/day). The intakes measured directly were similar to those found in equation 4 and higher than those found by equation 3. The mean of rumen fill of 7.5 kg was superior to those of 5.2 kg estimated by equation. The prediction equations based on in situ degradability parameters do not supply estimates of DM intake, NDF intake and rumen fill in agreement with values obtained by direct methods.

Influência da queima e aditivos químicos e bacterianos na composição química de silagens de cana-de-açúcar

The objective of this trial was to evaluate the effect of the chemical (urea, sodium benzoate, and sodium hydroxide) and microbiological (Propionibacterium acidipropionici + Lactobacillus plantarum, and Lactobacillus buchneri) additives on the sugarcane nutritive value, ensiled crude or after burned, using a factorial scheme 2 (burned or crude sugar cane) x 6 (five additives urea, sodium benzoate, sodium hydroxide, Propionibacterium acidipropionici + Lactobacillus plantarum, and Lactobacillus buchneri plus control). It was evaluated the sugar cane chemical composition, before and after ensilage. The sugar cane NDF contents increased (51.3%, before ensilage) to 67.8% after fermentation period. The highest true digestible dry matter recovery values, 83.6 and 79.8% were observed on the burned sugar cane silage treated with NaOH or L. buchneri, respectively. The NaOH, and L. buchneri showed more efficiency in reducing nutritive looses during the fermentation phase of the crude or burned sugar cane silage.

Consumo de capim-elefante com diferentes idades fornecido para vacas leiteiras

The 30, 45 and 60 day-old elephant grasses were evaluated by monitoring their nutritional profile and DM (DMI) and NDF (NDFI) intake by crossbred lactating cows in a 3 × 3 Latin square trial, where the split-plots were the rumen evacuation times: 0, 2, 4 and 6 h after meal. Chemical composition, in vitro dry matter digestibility and ruminal content ranged with grass age. Means (in kg/cow/day) of DMI and NDFI of 30 day-old grass (8.0 and 5.3) were lower than those of grasses with 45 days (10.0 and 6.6) and 60 days (11.0 and 7.3). The maximum of rumen fill was observed at 4:22, 3:55 and 3:49 hours after feeding for treatments with 30, 45 and 60 day-old elephant grass, respectively. Rumen fill did not limit the DMI and NDFI of elephant grass, but the dry matter intake of 30 day-old grass may be affected by the wet content.

Degradação ruminal e síntese de proteína microbiana em bovines alimentados com silagem de sorgo contendo tanino suplementado com concentrado ou uréia

This work aimed to determine ruminal parameters of dry mater (DM), neutral detergent fiber (NDF) and protein synthesis in the rumen of animals fed diets based on sorghum with different tannin levels. In situ degradation was evaluated by rumen incubation of level 1 (L1) and level 2 (L2) sorghum silages during 0, 6, 24, 48 and 96 hours. A duplicated 4 × 4 Latin Square was used. Potential degradability (PD) of DM was similar among silages, whereas the effective degradability (ED) decreased when the diets were supplemented with concentrate. Microbial nitrogen flux and microbial synthesis efficiency were not affected by roughage source. The synthesis efficiency, expressed in organic matter and crude protein digested in rumen, was higher in L1 tannin diets supplemented with concentrate. There was not relationship between the presence of tannins and the parameters of ruminal degradation.

Desempenho de bovinos em pastejo submetidos a duas frequências de suplementação no período da seca

This work was carried out to evaluate different frequencies of supplementation during the dry season. Forty-eight Nellore steers with 320 kg of initial live weight were fed with Brachiaria brizantha cv. Marandu pasture on a continuous stocking rate. The animals were submitted to following treatments: Daily supplementation and supplementation three times a week. The animals in both treatments received 7 kg of supplementation animal -1 weekly, and were weighted at 28-day intervals. The data were analyzed by the MIXED procedure in SAS (2004), with measurements repeated over time. The study observed average forage allowance of 4.2 tons of DM ha-1, with 3.5% CP, 82.24% NDF and 64.97% ADF. There was no difference (p < 0.01) among daily weight gains of animals who received daily supplementation and those received supplementation three times a week (0.23 and 0.13 kg day -1, respectively). Therefore, the supplementation intervals did not influence steer performance during the dry season.

Diferentes procedimentos na determinação de indicadores internos para estimativa de produção fecal e fluxo duodenal de matéria seca em bovinos

Times of in situ incubation (144 and 288h) for determination of internal markers IADF and INDF and the effects of differents procedures (wash or not the nylon bag every 72h incubation) was evaluated in samples of diet, duodenal digesta and cattle feces. The duodenal flow dry matter and fecal production utilizing the internal markers to compare with the external marker chromium oxide there was estimated. The animals were fed with sorgum silage, concentrate or urea. In this experiment, a latin square design was used, in a factorial scheme (two times of incubation × two processing nylon bag). No was observed effect of the incubation time or processing in the internal markers INDF and IADF concentration and the in situ incubation after 144h is adequate to reproduce the indigestible markers fraction in samples. For fecal production estimation, the external marker chromium oxide presented similar result (1.26 kg day-1) as the total fecal collection (1.49 kg day-1). Both the internal markers overestimate the duodenal flow dry matter when compared with the external marker chromium oxide.

Digestibilidade e Parâmetros Ruminais de Bovinos Consumindo Brachiaria Brizantha Cv. Marandu

This experiment aimed to evaluate nutrient intake, total and partial digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral (NDF) and acid (ADF) detergent fiber and ruminal parameters, ammonia concentration and volatile fatty acids, in beef cattle fed palisade grass (Brachiaria brizantha cv. marandu) at two regrowth ages, 30 and 60 days, at two times of year (January and February). The intake of DM, OM and CP was influenced by forage age of regrowth with high values for 30 days; this was influenced by time of year, being observed in February the higher intake by animals. DM digestibility average was 60.7 and 59.4% for 30 and 60 days of forage regrowth, respectively, however, was observed effect of interaction between regrowth and time of year, the same comportment was observed for OM, averages were 63.9 and 63% for respective ages of regrowth. CP digestibility was higher for 30 days, 70.8%, than for 60 days of regrowth, 57%. The NDF and ADF digestibilities were influenced by the interaction between regrowth and time of year; their average for 60 days of regrowth in January were respectively 54.8 and 48.5%, being the lower values and, in February, the higher values: 64.9 and 60.4%. The ruminal average digestibility was 79.5, 86.2, 99.4 and 96.7% of the total degradable for DM, OM, NDF and ADF, respectively. Effects of regrowth and time of year there were not recorded. Two hours after the morning meal was observed the ammonia ruminal concentration peak. The acetate:propionate: butirate ruminal ratio observed was 74:18:8(%).