Leandro das Dores Ferreira da Silva

Digestão total e parcial de alguns componentes de dietas contendo diferentes níveis de casca de soja e Fontes de nitrogênio, em bovinos

This experiment was conducted to evaluate the effect of two levels of soybean hulls and three sources of protein on the total and partial rumen and intestinal digestion. Six Holstein-Zebu steers averaging twelve months of age and 229 kg BW were fistulated in the rumen and in the abomasum and distributed in a 6x6 Latin square and fed ad libitum individually. The consumption and the total and partial digestibility of the nutrients were evaluated. There was no effect of the source of protein on consumption, amounts of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) in the rumen, abomasum and in the faeces and on the digestibility coefficients of these components. On the other hand, increasing the levels of soybean hulls significantly increased the coefficients of digestibility in the whole digestive tract. However, the levels of soybean hulls did not affect the digestion of CP, NDF and ADF in the intestines. The results indicate that soybean hulls can replace maize, due their degradation similarity, and can partially replace the roughage in rations for ruminants, by having high levels of fiber with great potential and speed of ruminal fermentation. Poultry by-product meal and starea can replace soybean meal without negative effects on the digestion of their nutritive components.

Consumo e Digestibilidade Aparente das Silagens de Milho (Zea mays L.), Sorgo (Sorghum bicolor (L.) Moench) e Girassol (Helianthus annuus L.)

The experiment was carried out with the objective of determining the daily average intake (DAI) and apparent digestibility coefficient (ADC) of corn, sorghum and sunflower silages nutrients. The nitrogen balance was also evaluated. Nine castrated, male sheeps, kept in metabolism cages, in a 3 x 3 (three treatments and three periods), latin square design, were used. DAI of dry matter (DM), acid detergent fiber (ADF) and crude protein (CP) of corn silage of sunflower silage did not differ. DAI of neutral detergent fiber (NDF) and ether extract (EE) were higher in corn and sunflower silages, respectively. ADC of DM and EE were higher in sunflower silage than in sorghum silage. ADC of NDF and CP were similar for all silages.

Eficiência produtiva em vacas primíparas das raças Aberdeen Angus e Charolês

The objective of this work was to evaluate the productive efficiency of beef cows. Thirty Angus and 32 Charolais primiparous cows, pregnant at the beginning of the experiment with straightbred or crossbred calves, were evaluated. The cows were submitted to different feeding management during winter and spring: T1 ¾ Native pasture, T2 ¾ Cultivated pasture for 60 days (24 hours/day), from early September to early November, T3 ¾ Cultivated pasture for two hours a day, for 60 days, from early July to early September, T4 - Cultivated pasture for two hours a day, for 60 days, from early July to early September, and more 60 days on cultivated pasture (24 hours/day), from early September to early November. Productive efficiency was measured by CALVINGPE = (W205/CWC)*100, WEANINGPE = (W205/CWW)*100, CALVINGMBPE = (W205/CWC.75), WEANINGMBPE = (W205/CWW.75) and TDNPE = TDNTOTAL/W205, where W205 is the calf weaning weight and CWC and CWW are the cow weight at calving and weaning, respectively. TDNTOTAL is the total energy requirement (maintenance + milk production) of the cow. Aberdeen Angus cows, cows with male calves and cows with crossbred calves were more efficient. Cows that had access to cultivated pasture for a long period of time (T4) had better performance than those that were maintained on native pasture only (T1). Cows of the other treatments had intermediate performance.

Desempenho de bovinos confinados alimentados com dietas à base de farelo de algodão, uréia ou amiréia

The objective of this experiment was to evaluate the performance of feedlot beef cattle fed diets supplemented with protein concentrate based on cottonseed meal (CSM) urea (UR) or starea (ST), using corn silage as forage. The feedlot period was 80 days. The diets were constituted maintaining the forage:concentrate proportion in the 63:37 level, with nearly 13% CP. No difference was observed in daily weight gain during the experimental period among the CSM, UR or ST treatments (1.14, 1.17, and 1.23 Kg/animday) or in the dry matter intakes in % LW (2.63, 2.60, and 2.60), g/kg 0.75 •day (136.19, 134.74, and 134.81) or kg/anim.•day (9.42, 9.35, and 9.40), respectively. The CP intakes values were 1.28, 1.24, and 1.34 kg of CP/anim.•day and 18.54, 17.86, and 19.24 g/kg .75 •day for the CMS, UR or ST treatments and they did not differ among each other. Values of feed:gain ratios obtained for dry matter were 8.41, 8.01, and 7.67 kg DMI/kg DWG and for the protein:gain ratios, 1.15, 1.06, and 1.09 kg CPI / Kg DWG, respectively, for the CPM, UR and ST treatments, that were similar.

Degradabilidade ruminal in situ da matéria seca e proteína bruta de duas variedades de grão de soja com diferentes teores de inibidor de tripsina, em bovinos

Four ruminally fistulated Holstein, distributed in randomized blocks and fed with coastcross grass, were used. They were supplemented with 2 kg of concentrate containing ground soybean, put through the rumen fistula daily, at 7 a.m. and 6 p.m. Nylon bags were incubated into the rumen of each animal, and contained samples of each of the following feed: ground soybean (S); low fat ground soybean (LFS); ground low trypsin inhibitor soybean (LTIS); ground low fat and low trypsin inhibitor soybean (LFLTIS); and soybean meal (SM). Dry matter (DM), organic matter (OM) and crude protein (CP) solubility and disappearance into the rumen were determined after 6, 24 and 48 hours of incubation. The DM, OM and CP solubilities of S were higher than low trypsin inhibitor soybean. The DM and OM effective degradability (ED) of LTIS was about 9% lower than the observed values of S and the ED of the LTIS crude protein was about 6% lower. All feedstuffs showed high degradation rate for the studied nutritive components, with fermentation rates varying from 5% for SM to 15%/hour for LFLTIS. The LTIS showed the lowest nutritive component degradation. The values suggest that these feedstuffs should be associated with others with low degradation velocity for ruminant feed as a way of improving the synchronization between the release of ammonia, aminoacid, peptides and ketoacids into the rumen, when the increase of microbial protein yield and/or increase the amount of bypass protein is necessary.

Carcaça de borregos Ile de France inteiros ou castrados e Hampshire down castrados abatidos aos doze meses de idade

A total of 24 lambs, eight intact Ile de France, eight castrated Ile de France and eight castrated Hampshire Down, were used in this experiment with the main objective of evaluating quantitative and qualitative carcass traits. The animals were raised on a Coast-Cross pasture and slaughtered at 12 months of age. Carcasses from intact Ile de France lambs had significantly more neck than carcasses from castrated Ile de France lambs. No other differences were observed between carcasses from intact or castrated Ile de France. However, differences between breeds were observed for tissue composition of the shoulder. Shoulders from Ile de France carcasses (intact or castrated) presented greater percentage of muscles and greater relation of muscles/bones than shoulders from Hampshire Down lambs. Results indicate that intact males can be recommended for sheep meat production systems, when slaughter occurs up to 12 months of age.

Desempenho e características de carcaça de bovinos de diferentes grupos genéticos

This experiment was carried out to evaluate the performance of steers of three genetic groups: Nellore (NN), ½ Guzerat × ½ Nellore (GN) and ½ Brahman × ½ Nellore (BN). Forty-one steers, 24 mo old, kept in pasture of Brachiaria grass. All animals were from the same herd and were raised under the same conditions and slaughtered at 3 years old. At the beginning of the experiment and at slaughter, Brahman-crossed animals were heavier than the animals from the other two groups. Means for body weight for the groups NN, GN and BN, were respectively, 324, 320 and 343 kg at the beginning of the experiment, and 474, 470 and 499 kg at slaughter. However, average daily gains were similar among the groups (0.388, 0.386 and 0.409 kg/d, respectively). Animals of BN group produced heavier hot carcasses (253 × 238 kg) than those obtained in the GN group, but these two groups did not differ from the NN group (242 kg). Percentages of muscle, fat and bones in the carcass were similar among the groups. Other carcass traits (dressing percentage, ribeye area, fat thickness and marbling) and meat tenderness, measured by a trained panel or by a texturometer were, also, similar among the three genetic groups. The crossing of other zebu breeds (Brahman or Guzerat) with Nellore did not improve quality characteristics of carcasses and meat; however, crossing with Brahman resulted in heavier animals with heavier carcasses.

Níveis de energia na alimentação de cordeiros em confinamento e composição regional e tecidual das carcaças

The objective of this study was to evaluate quantitative characteristics and carcass regional and tissue composition of lambs submitted to different energy levels (2.23, 2.54 and 2.85 Mcal ME/kg DM) in the diet and slaughtered with 32.2 ± 3.8 kg body weight and at average age of 145.6 ± 20.1 days. The diets were isoproteic (16.70% CP) and fed to 18 no castrated crossbred Texel male lambs. The lambs were confined in individual pens, in a slotted floor sheep barn. The half left-side carcasses were splitted into the shoulder, leg, loin, ribs and neck. The tissue composition (bone, muscle and fat) was also evaluated in each cut. Except for loin percentage, energy levels presented a quadratic effect on the other cuts. The percentages of shoulder and neck were greatest at the middle energy level and the percentages of leg and ribs were lowest at this level. The energy level of the diet influenced the distribution of the cuts in the carcass, but it did not affect the average tissue composition of the carcass. The shoulder was the cut with the greatest tissue variation. The different cuts can be used to predict the average tissue composition of the carcass but the shoulder is the least indicated.

SILAGENS DE GIRASSOL (Helianthus annus L.), MILHO (Zea mays L.) E SORGO (Sorghum bicolor (L.) Moench) PARA OVELHAS EM CONFINAMENTO

The objective of this paper was to evaluate the performance of ewes receiving corn, sorghum or sunflower silages. Half of the dry matter diet came from the silages and the other half from a concentrate, 25% of soybean meal and 75% of ground corn. Forty-seven ewes were used and confined during a period of 70 days. Ewes receiving sunflower silage had a greater (P 0.05), respectively, for ewes receiving corn, sunflower and sorghum silages. Ewes fed sunflower silage showed greater percentage of hot carcass (53.14%) than the ewes fed sorghum (48.13%) or corn (46.36%) silages. It can be concluded that the sunflower silage is better than corn and sorghum silages for termination of feedlot sheep.

Fatores que afetam o desempenho de cordeiros Santa Inês puros e cruzados do nascimento ao desmame

The objective of this study was to evaluate the environmental effects (age of dam, type of birth, sex of the lamb and year of birth) and genetic groups on the weight and morphometric measurements of lamb at birth and at weaning; test regressions for predicting weight of lambs by the measurements and describe the type of growth of the measures. Lambs of young ewes (2 teeth) had lower average for all characteristics except height at weaning. The average birth weight ranged from 3.34 ± 0.14kg in the offspring of two teeth ewes to 3.94 ± 0.09kg in the lambs of eight teeth ewes, and for weaning weight ranged from 12.19 ± 0.72kg in the offspring of two teeth ewes, and 14.79 ± 0.62 in the lambs of six teeth ewes. The single birth lambs had highter averages than the twins. Means for birth weight ranged from 3.24 ± 0.11kg to 4.08 ± 0.06kg and for weaning weight from 11.18 ± 0.59kg to 15.81 ± 0.35kg, the averages were lower for twins and greater for single lambs. The genetic group affected the weight and the length and height at birth, where purebred Santa Ines lambs presented greater averages than ½ Santa Ines lambs. The year of birth influenced all traits. All correlations between weights and measures were significant. It is possible to predict the weight on the basis of measures.