Carlos Eduardo Furtado

Avaliação da silagem de grãos úmidos de milho na alimentação de eqüinos em crescimento: valor nutricional e desempenho

O objetivo deste trabalho foi estudar os efeitos de diferentes porcentagens do sabugo (0, 5, 10 e 20%) na materia verde (MV) e de quatro periodos de amostragem (zero, dois, quatro e seis dias apos a abertura dos silos) sobre a qualidade da silagem de graos umidos de milho ( Zea mays L.). O arranjo fatorial 5 x 4 foi estudado segundo delineamento inteiramente casualizado, com tres repeticoes. Nao houve efeito do periodo de amostragem sobre as variaveis estudadas. A capacidade-tampao e o pH nao foram afetados pela presenca do sabugo, e o teor de carboidratos soluveis e N amoniacal aumentaram em ate 1,2 e 1,89 unidade percentual, respectivamente, em relacao a silagem exclusiva de graos de milho. O aumento na porcentagem de sabugo reduziu os teores de materia seca (MS) (de 63,9% para 58,6%), proteina bruta (PB) (de 10,0% para 7,3%), extrato etereo (EE) (de 4,87% para 3,92%) e os valores da digestibilidade in vitro de materia seca (DIVMS) (de 90,5% para 79,1%) das silagens, e aumentou os teores da fibra em detergente acido (FDA) (de 3,3% para 12,9%) e da fibra em detergente neutro (FDN) (de 15,16% para 26,1%). Os valores de energia bruta (EB) nao foram afetados (P>0,01) pela presenca do sabugo nas silagens.

Digestibilidade aparente e desenvolvimento de eqüinos em crescimento submetidos a dietas compostas por diferentes níveis de substituição do feno de Tifton 85 pela casca de soja

Two experiments were carried out to evaluate the nutritional utilization of soybean hulls for growing horses. In the digestibility assay, four colts, averaging 11 months of age and 350±26kg, were used to determine the nutritional value of diets with soybean hulls. The experimental design was square latine (4 x 4). Four diets were used, one as a reference and three as test diets, where the soybean hulls replaced 33.3, 66.6 and 100% of the Tifton 85 hay of the reference diet. Total feces collection was used to determine the apparent digestibility coefficients of the diets. Effects on the apparent digestibility coefficient of the dry matter were observed (62.48, 66.35, 79.49 and 82.77%; 66.08, 65.16, 75.41 and 74.09%; 62.59, 62.62, 75.17 and 74.05% and 61.12, 57.15, 73.34 and 72.27%, respectively, for the test diet and the diets with 33.3, 66.6 and 100% of soybean hulls replacing the Tifton 85 hay). No effects on the apparent digestibility coefficients of crude protein were observed (69.67, 71.95, 74.08 and 75.03%, respectively, for the test diet and the diets with 33.3, 66.6 and 100% of soybean hulls replacing the Tifton 85 hay. In the development experiment, 16 colts, averaging 15 months of age and 255.19±21.12 kg, were used. A completely randomized design with four replications and four animal by each experimental unit, for a period of 75 days, was used. The trials consisted of a reference diet and three levels of substitution (33.3, 66.6 and 100%) of hay by soybean hulls, formulated to be isoprotein and isocaloric. No diet effects on the perfomance variables were observed in growing horses. It was concluded that diets for equines can be formulated with total substitution of hay for soybean hulls without affecting development.

Importância nutricional e metabólica da fibra na dieta de equinos

O equino e um herbivoro nao ruminante capaz de suprir grande parte ou a totalidade da sua demanda nutricional pela ingestao de gramineas. Apresenta a regiao ceco-colica bastante desenvolvida, sendo este o principal sitio de fermentacao. Este processo tambem ocorre na regiao aglandular do estomago, porem a producao de acidos graxos volateis e inferior, quando comparado ao intestino grosso. O conhecimento do sitio de aproveitamento de cada ingrediente e de suma importância para a combinacao dos mesmos, favorecendo o otimo aproveitamento de cada um deles e evitando excessos que podem ser prejudiciais ao metabolismo do equino. O estudo atual do fracionamento de carboidratos, por mais que nao seja adaptado a fisiologia e metabolismo dos equinos, nos fornece informacoes sobre as diferentes fracoes que o compoem e com isso pode-se inferir sobre a producao de energia por cada fracao gerada. A manutencao de equinos em pastejo ou sob o fornecimento de feno ou alimentos volumosos e essencial para a manutencao da atividade e saude do seu trato digestorio. O aporte minimo de 12% de FDN garante tal situacao. Atualmente, com o objetivo de aumentar a disponibilidade de energia, ingredientes como a polpa citrica, polpa de beterraba e casca de soja, vem sendo utilizados nas formulacoes. Estes ingredientes de fermentacao mais rapida e facil, sao uma alternativa segura para elevar a concentracao energetica da dieta de equinos, por proporcionar a diminuicao do aporte de amido na dieta de equinos. Sabe-se entretanto, que com a elevacao na qualidade do volumoso, maiores concentracoes de carboidratos soluveis e de rapida fermentacao sao encontrados disponiveis ao longo do trato digestorio dos equinos levando a alguns disturbios metabolicos como a laminite e a sensibilidade a insulina. Com o correto manejo dos animais em pastejo e conhecimento do ciclo da planta e possivel minimizar tais problemas. Objetivou-se revisao da acao fisiologica e metabolica das diferentes fracoes fibrosas, em cada compartimento do trato digestorio, bem como destacar os ingredientes volumosos com suas diversas fracoes, os quais possibilitam sugerir manejo alimentar adequado para os equinos.

Digestibilidade aparente de dietas com diferentes níveis de farelo de canola para cavalos

Four male equines averaging 3.5 years old and live weight of 400-450 kg were distributed in a 4 x 4 Latin square (period x animal) experimental design. The inclusion of canola meal levels in diets were 0.0; 2.5; 4.5 and 7.0%, replacing respectively 0, 35, 65 and 100% of crude protein (CP) from soybean meal. The diets were isoproteic (13% CP) and isocaloric (4250 kcal/kg). The total fecal collection method was used for the determination of the nutrient digestibility coefficients. There was no effect of the substitution levels of soybean meal crude protein by canola meal for none of the analyzed nutrients. The average obtained values for the apparent digestibility of dry matter, gross energy, crude protein, neutral detergent fiber and acid detergent fiber were 64.04, 55.82, 62.89, 51.20 and 42.05%, respectively. The concentrate for equines can be formulated with total substitution of soybean meal crude protein by canola meal (inclusion level of 7%) without negatively affects the nutrient digestibilities, becoming as an alternative protein source in the diets of these animal species.

Uso de levedura em equinos alimentados com dietas compostas de fenos de diferentes qualidades nutricionais

In order to evaluate the effect of using probiotic (Saccharomyces cerevisiae) in diets for horses, it was used four male equines, with average body weight of 400 kg, in a 4 o 4 Latin square design. Diets were composed of concentrated and 85 Tifton grass hay (low quality) or alfafa hay (high quality), with or without addition of yeast. Each experimental period lasted 36 days, with total fecal collection for determination of apparent digestibility coefficients of the nutrients and fecal collection for determining pH and fecal microbiology. Use of probiotic did not affect apparent digestibility coefficients of the diets, except for ether extract. Hay nutritional quality affected coefficients of dry matter digestibility, crude protein and ether extract (EE) only for diets with Tifton grass hay without probiotic and with alfafa hay with probiotic. The utilization of yeast culture increased the Lactobacillus population in feces of animals fed diet with Tifton grass hay with probiotic. Probiotic was not used in population of Lactobacillus in diets of alfafa hay (good quality). Streptococcus population in the diet increased as yeast was supplemented in both diets with Tifton grass hay as that with alfafa hay. Diet with 85 Tifton grass without probiotic promoted reduction in fecal pH values 14 and 17 hours after feeding. Considering the values of fecal pH in this periods after feeding, the diets supplemented with probiotic showed values higher than those without addition of yeast.

Parâmetros bioquímicos de equinos submetidos à simulação de prova de enduro recebendo dietas com adição de óleo de soja

The objective of this study was to verify the effect of increasing soybean oil addition levels in the concentrate, on the enzymatic activity CK (Creatine Kinase), LDH (Lactate Dehydrogenase), AST (Astarte aminostrafase), as an indication of energetic metabolism. Compond experimental diets were given with five oil levels (control, 6, 12, 18 and 24% concentrate). Twenty Arabian equines, average weight 400 kg were submitted to a 80 km endurance race on a treadmill. The endurance was divided into four 20 km rings with an average duration of one hour and 10 minutes. A significant effect of oil addition and the covered distance was observed on the variables AST, CK, LDH and they present the respective expressions AST and (7,045-0,2292x+0,007991x2+ 0,008517z- 0,0003282xz) CKand(8,06-,07020x+0,05546x2-0,001262x3+0,01204z+0,0006207xz) , LDH and (6,624-0,3522x+0,03448x2-0,0008382x3+0,02401z-0,0007489xz) . The oil is an important and well-used energy source for horses in exercise, because its addition to the diet of animals submitted to endurance test cause metabolic alteration that favored energy production. The animal metabolism save its energy reserves derived from glucose and favored the use of the oil. The smaller plasmatic activity of the AST, CK and LDH, enzymes with the addition of oil to the diets indicated directioning of the energy metabolism to β-oxidation. As the enzymes show several isoenzymes, it was concluded that the enzymes studied act widely on the energetic metabolism, favoring constant ATP reposition during all exercise.

Desempenho e parâmetros sangüíneos de eqüinos em crescimento submetidos a dietas com diferentes níveis de farelo de canola

Diets composed by four different levels (0; 53; 65 and 100%) of canola meal replacing soybean meal crude protein (CP) were evaluated using foals. The diets were isoproteic (17% CP) and isocaloric (4200 kcal/kg). Sixteen Managalarga breed foals, eight males and eight females, averaging 10 months and 218 kg LW, fed a total intake of 2.5% LW on dry matter (DM) basis were used. The diet was composed by 60:40 forage to concentrate ratio. A completely block experimental design, with four blocks and four treatments, was used. There were no effect of treatments on the performance variables (average daily gain, wither height, heart girth and cannon bone circumference) and blood parameters (glucose and urea) of growing foals. In the concentrate for growing foals from 9 to 11.5 months old, the soybean meal can be replaced by canola meal.

Influência do peso vivo, da idade e do sexo sobre características de carcaças de equinos

With the objective of evaluating the quantitative characteristics of carcasses of equines, 72 undefined breed equines were classified by body weight, age and sex. It was determined cold carcass weight, cooling loss, carcass yield, front and back weight and muscle/bone ratio. The statistical model used was a completely randomized design in a 2 x 3 x 3 factorial scheme, with the two sexes, three age ranges and three ranges of body weights. The highest weight range corresponded to the highest carcass weight with average of 201.71 kg, and the highest muscle/bone ratio with 77.69%. The lowest cooling loss was observed in the lowest weight range, with 2.03%. The average for carcass yield was of 51.20%, for front and back, 54.86% and 45.06%, respectively. There was an interaction between sex and age of the animals for carcass yield variable, which was higher in young male equines (until 8 years of age) than in older animals and females. Therefore, it is suggest priorization of young and heavier animals for equine slaughter because they present higher amount of exportation-type meat.

Blood parameters and apparent digestibility of concentrate with rice oil for horses

Apparent digestibility coefficients and serum parameters were measured to evaluate the effect of supplementing feed concentrates with rice bran oil in horses. Twelve horses (6 males and 6 females) with a mean age of 18 ± 4 months old and mean live weight of 306 ± 22.6 kg were used. Treatments consisted of increasing rice bran oil concentrate levels of 0, 3.5, 7.0, 10.5, 14.0 and 17.5%, considering a daily intake of 2.25% live weight on a dry matter basis. A dietary effect of supplementation on the apparent digestibility of gross energy (y = 64.55 - 0.58x) was observed (P 0.05). Supplementation did not affect serum glucose levels (P>0.05), but cholesterol was affected (P 0.05). A dietary effect on the triglyceride (y = 15.73 - 0.96x + 0.0524x2) and HDL (high-density lipoprotein) (y = 45.24 + 1.0499x) parameters was observed (P<0.01). While the use of rice bran oil does affect blood parameters associated with lipid metabolism, rice bran oil levels up to 17.5% concentrate do not negatively affect the apparent digestibility of dietary nutrients.

Biological availability and calcium requirements of growing equines receiving diets with different calcium levels

The objective of this work was to study the calcium metabolism in growing equines receiving diets with different calcium levels. Twelve male were used, with average age of twelve months and average alive weight of 221,0 kg. The treatments consisted of three diets, composed for increasing calcium levels (low = 0.15%-N15; standard = 0.45%-N45; high = 0.75%-N75), and standard phosphorus level (0.23%). Each animal was injected, through the right jugular vein, the volumes of a syringe, which corresponded to about 7.4 MBq of 45Ca (CaCl2). After the injection, blood samples (10 mL) were collected through left jugular vein at five minutes, 1, 2, 4, 6, 24, 48, 72, 96, 120 and 144 hours. The feces were daily collected in the morning, 24 hours after the application of the radionuclide until the seventh day, and an aliquot of 5% of the daily total excreted was collected and stored in freezer for posterior analysis. The same procedure of excrements was adopted for urine, when samples of 1% of the daily total volume had been collected. The experimental techniques used a completely randomized design with three treatments and four replications. No effects were observed on the plasma calcium, total calcium in urine and endogenous calcium in feces, with average values of 11,76; 5,54 and 20,86 mg/kgLW/day, respectively. No effects were observed for the biological calcium availability, with 81.67%, on average. Linear regressions between calcium levels in the diet and total calcium ingested, absorbed calcium, total calcium in feces and restrained calcium have been respectively verified, which were expressed according to the following equations: y=10.7+2.78x r2=1.0; y=12.41+2.24x r2=0.99; y=5.97+0.92x r2=0.93 and y=6.4+1.70x r2=0.94, with averages of 135.80; 113.21; 47.37 and 82.90 mg/kgLW/day, respectively.The objective of this work was to study the calcium metabolism in growing equines receiving diets with different calcium levels. Twelve male were used, with average age of twelve months and average alive weight of 221,0 kg. The treatments consisted of three diets, composed for increasing calcium levels (low = 0.15%-N15; standard = 0.45%-N45; high = 0.75%-N75), and standard phosphorus level (0.23%). Each animal was injected, through the right jugular vein, the volumes of a syringe, which corresponded to about 7.4 MBq of 45Ca (CaCl2). After the injection, blood samples (10 mL) were collected through left jugular vein at five minutes, 1, 2, 4, 6, 24, 48, 72, 96, 120 and 144 hours. The feces were daily collected in the morning, 24 hours after the application of the radionuclide until the seventh day, and an aliquot of 5% of the daily total excreted was collected and stored in freezer for posterior analysis. The same procedure of excrements was adopted for urine, when samples of 1% of the daily total volume had been collected. The experimental techniques used a completely randomized design with three treatments and four replications. No effects were observed on the plasma calcium, total calcium in urine and endogenous calcium in feces, with average values of 11,76; 5,54 and 20,86 mg/kgLW/day, respectively. No effects were observed for the biological calcium availability, with 81.67%, on average. Linear regressions between calcium levels in the diet and total calcium ingested, absorbed calcium, total calcium in feces and restrained calcium have been respectively verified, which were expressed according to the following equations: y=10.7+2.78x r2=1.0; y=12.41+2.24x r2=0.99; y=5.97+0.92x r2=0.93 and y=6.4+1.70x r2=0.94, with averages of 135.80; 113.21; 47.37 and 82.90 mg/kgLW/day, respectively.