Produção e composição do leite de vacas mantidas em pastagens de capim-elefante submetidas a duas frequências de pastejo

The objective of this study was to evaluate two grazing intervals (IG) for elephant grass (Pennisetum purpureum Schum cv. Cameroon) pasture: one variable, determined by the entry of animals to the paddocks when 95% of active photosynthetic radiation was intercepted by the sward, and fixed 26-day grazing interval. Eight dairy cows were used, averaging 124 days lactation, 516 kg body weight and 17.5 kg daily milk production at the beginning of the trial. The experimental period was 80 days divided into four sub-periods of 20 days each. Data were analyzed in a cross-over design. The grazing frequencies did not influence milk production and composition, plasma urea nitrogen, body condition score and variations in body weight. However, the stocking rate and milk production per hectare were higher for pasture with interval of grazing determined by 95% of active photosynthetic radiation. Thus grazing frequency defined in variable intervals by sward interception of active photosynthetic radiation result in higher milk production per area unit.

Níveis de proteína digestível e energia digestível em dietas para tilápias-do-nilo formuladas com base no conceito de proteína ideal

This study was carried out to determine the best digestible energy and digestible protein ratio in feeds for Nile tilapia (Oreochromis niloticus) juveniles 30.0 +/- 4.21 g) based on digestible amino acids and the ideal protein concept). Twelve rations were formulated with protein levels 22.0; 26.0; 30.0 and 34.0% of digestible protein and levels 3,000, 3,300 and 3,600 kcal/kg digestible energy. The digestible energy/digestible protein ratio was between 8.94 and 15.19 kcal/g. Three hundred and twenty four tilapias were randomly distributed in thirty six 250 L circular tanks at a density of 9 fish/tank, a total of 12 treatments with three replications. After 60 days, there was no significant difference in weight gain, daily weight gain and feed conversion ratio among the studied treatments. A linear increase was observed in fillet yield with increasing digestible protein. With respect to feed cost/kg weight gain, the treatment with 30.0% DP and 3,000 kcal/kg DE presented low cost and better cost effectiveness index. Therefore, it was concluded that digestible energy did not influence the productive performance parameters and that effective feeds can be formulated with DP levels lower than 34% when feeding juvenile tilapias. The ration should be formulated based on the concept of ideal protein.

Composição Corporal e Exigências Nutricionais em Cálcio e Fósforo para Ganho e Mantença de Cordeiros Santa Inês dos 15 kg aos 25 kg de Peso Vivo

The research was carried out to determine body composition and calcium and phosphorus requirements of Santa Ines lambs. Eighteen entire male lambs with average initial live weight of 15 kg were used. The animals were allotted to three groups: six animals were slaughtered at the beginning of the experiment, to access the amount of calcium and phosphorus present in the body, as reference animals for the comparative slaughter technique. Six animals were ad libitum fed and six were restrict fed (maintenance level plus 20%). The animals ad libitum and restrict fed started the experimental period by pairs and they were both slaughtered when the first reached 25 kg body weight. The body composition was estimated through the prediction equations obtained by regression of the logarithm of the amount of calcium and phosphorus in the empty body on the logarithm of the empty body weight. Net requirements for calcium and phosphorus for maintenance and the absorption coefficient were obtained through the correlation between the amount of each mineral consumed and retained in the animal body. The net requirements maintenance for live weight gain were obtained by means of derivation of the prediction of body composition equations. The net requirements maintainance of calcium and phosphorus for animals from 15 to 25 kg body weight were: 305 mg Ca/day and 325 mg P/day and net requirements for kg of the body weight gain for animals with 15 and 25 kg LW were 11.41 and 10.33 g Ca and 5.72 and 4.94 g P, respectively. The absorption coefficients were estimated to be .44 and 0.55 for Ca and P, respectively.

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 e morfometria da mucosa de duodeno de frangos de corte alimentados com farelo de canola, durante o período inicial

A trial was carried to verify the effect of increasing levels (0, 10, 20, 30 and 40%) of canola meal in diets of broiler chickens on performance and mucous morphology, during the starting period (1 - 21 days). One thousand 1-d male chicks were assigned to a randomized experimental assay, with five treatments, four replicates and 50 birds per experimental unit. At the 1 st, 21 st and 41 st days, the birds and the rations were weighed. At the 21 st day, two birds of each experimental unit were sacrificed for collection of a duodenum segment to evaluate the intestinal morphometry. The results demonstrated that increasing levels of canola meal resulted in linear reduction on weight gain, weight and feed intake and worst feed conversion. During the growing period (21 to 41 days), when all birds received similar diet, average weight and weight gain decreased, as the canola meal levels increased, while feed conversion and feed intake were similar. Data regarding mucous morphology, submitted to the regression analysis, demonstrated that the crypt depth increased, as the canola meal levels increased. It is possible to include up to 20% of canola meal without damages on broiler performance and digestive tract.

Desempenho e características da carcaça de tourinhos santa gertrudes confinados, recebendo dietas com alto concentrado e níveis crescentes de polpa cítrica peletizada

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Peso de abate de machos não-castrados para produção do bovino jovem. 1. Desempenho em confinamento e custos de produção

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Peso de abate de machos não-castrados para produção do bovino jovem. 2. Peso, Idade e caracteristicas da carcaça

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Características anátomo-estruturais da pelé de ovinos (ovis áries L.) lanados e deslanados, relacionadas com o aspecto físico-mecânico do couro

The objective of the study was establishing the anatomical-structural differences between the skin of non-wool sheep of the Morada Nova breed and wool-on sheep of the Polwarth or Ideal breeds and their relations to the physical-mechanical characteristics of their leather after tanning. Ten animals of both breeds were used, with five animals of approximately one and four years of age of each breed. The animals were slaughtered, and immediately after skinning, samples were taken viewing the microtomy of the skin in the dorsal, lateral, ventral, hind and palette regions, parallel and perpendicular to the head-tail axle, and perpendicular to the grain of the skin. The skins were depilated, chromium-tanned and re-tanned. From the leather, three samples were taken from the two directions considered from the regions studied for physical-mechanical analysis, for tension and tear resistance and distension on the lastometer. The average of the results of the physical-mechanical analysis were compared by Tukey test at the levels of 1 and 5% probability. The breed, the age, the region and the position exerted a positive effect on the values of the resistance of the leather to tension for the Morada Nova four year old sheep, reaching a minimum of 200 kg/cm . The region and the position exerted a positive effect on the values of tear-resistence of the leather for both breeds studied, reaching a minimum of 40 kg/cm. The resistance of the leather on distension was superior to 8 mm, for all the animals studied, not influenced by breed, age, region or position. The skin of the Ideal sheep presented a thermostatic skin layer greater than the reticular layer with great folicular and glandular density, contrary to the skin of the Morada Nova sheep where the thermostatic and reticular layers are of approximately the same thickness, with less folicular and glandular density.

Métodos de coleta de fezes e determinação dos coeficientes de digestibilidade da fração protéica e da energia de alimentos para o pacu, Piaractus mesopotamicus (Holmberg, 1887)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Resídue de polpas de frutas desidratadas na alimentação de leitões em fase de creche

It was evaluated chemically and biologically the powdered fruits pulp residue, used in human food industry. In the digestibility study it was used 12 commercial hybrids barrows piglets, with initial weight 12.2 ± 1,6 kg, allotted in individual cages. The treatments were a basal and a test diet. In the test diet the fruits pulp residue replaced 30% of the basal dry matter. The following values were obtained: dry matter 89,54%, starch 71,1%, glucose 5.4%, fructose 2,2%, crude protein 5,33%, gross energy 3771 kcal/kg, apparent digestible dry matter 96,01%, digestible energy 3448 kcal/kg, metabolizable energy 3389 kcal/kg. By bromatologic results and metabolism study, the powdered fruits pulp residue was characterized as an alternative to be evaluated in piglet diets. In the performance assay 90 piglets with initial weight of 6,60 ± 0,76 kg were allotted in a randomized block design, with six replications and three animals per experimental unit. The treatments were levels of powdered fruits pulp residue (0. 25, 50, 75 and 100%) replacing the corn of the control diet. The studied phases were initial-1 (14 days), initial-2 (21 days) and total period. On the performance there was no difference between the studied inclusion levels. For meal diets, the fruits pulp residue can replace the corn.

Efeito do nível de energia metabolizável da dieta no desempenho e metabolismo energético de frangos de corte

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação de carcaças de suínos da raça large white utilizando medidas convencionais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tendências genéticas para características relacionadas à velocidade de crescimento em bovinos nelore na região nordeste do brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Energia digestível para larvas de tilápia-do-nilo (oreochromis niloticus) na fase de reversão sexual

This experiment was conducted to evaluate different levels of digestible energy on the performance of Nile tilapia larvae (Oreochromis niloticus) during the sexual reversion phase. Three hundred and seventy-five larvae with initial average length and weight of 21.0±4.0 mg and 1.19±0.72 cm, respectively, were allotted to 25 30L-aquarium. A completely randomized design with five treatments and five replicates was used. The aquarium with 15 larvae was the experimental unit. The diets were formulated to contain levels of 3,300, 3,525, 3,750, 3,975, and 4,200 kcal/kg of digestible energy and to be isoprotein (38.6% digestible protein). The animals were fed ad libitum five times a day. At the end of the experiment, the averages of weight (PF), survival rate (SO), condition factor (FC) and length (CF) were analyzed. Linear reduction of fishes PF and CF, as the dietary digestible energy levels increased, was observed. No differences on fish SO and FC of different treatments were observed. Deleterious effects on performance due to the increasing dietary digestible energy levels were noticed for Nile tilapia larvae during the sexual reversion.