Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the effect of alternative protein sources (castor bean cake, sunflower cake, and sunflower seed) to soybean meal on the intake and performance of 40 lambs, initially weighing 19.8±1.84 kg, fed diets based on Tifton grass hay. The experimental design was completely randomized blocks. There were no differences in the nutrient intake of castor bean diets compared with soybean meal. The intake of nutrients in the sunflower cake and sunflower seed diets was decreased compared with soybean meal. The apparent digestibility coefficients of dry matter, organic matter, crude protein, and neutral detergent fiber of sunflower cake and sunflower seed diets were decreased compared with soybean meal. The average daily weight gain of animals fed the castor bean diet (0.190 kg) was not different from that of the animals fed the soybean meal diet (0.217 kg). The sunflower cake and sunflower seed diets provided less weight gain (0.171 and 0.135 kg d-1, respectively) than soybean meal due to the lower nutrient intake. The hot carcass yield and true yield were not affected by the protein sources. The neck, ribs, and ham weights were similar in lambs fed soybean meal and castor bean cake diets. It is recommended to use castor bean as an alternative protein source in the diet of lambs.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the intake and digestibility of silages containing pineapple pulp and coast-cross hay, with or without addition of urea, and the recovery of the markers chromium oxide (Cr2O3), indigestible neutral detergent fiber (iNDF), indigestible acid detergent fiber (iADF), and indigestible dry matter (iDM), in a digestibility assay, in sheep. Treatments were as follows: two levels of pineapple pulp (818 and 758 g kg−1) and two levels of urea (with and without urea), in a completely randomized design. Twelve sheep (three per treatment) were used, kept in metabolic cages. Fecal excreta were determined by total collection or estimated by using the markers. Marker samples were obtained in morning and afternoon collections, with mean concentrations obtained for both daily activities. The level of silage pulp did not affect intake, while addition of urea increased the intake of crude protein (CP), but did not influence the intakes of dry matter, organic matter, neutral detergent fiber, or acid detergent fiber. The digestibility coefficients of all afore-mentioned fractions increased with the increase in pulp, the same happening with the addition of urea. The internal marker with lowest variability among the internal markers was iADF, with mean values near 100%. Mean recovery of Cr2O3 was approximately 107%, but with lower variability among treatments. Inclusion of pineapple pulp in silage does not influence intake, while addition of urea only increases the intake of CP. The levels of pineapple pulp in silage with or without urea increase the digestibility of the silage. Indigestible acid detergent fiber is the marker with lowest variability of recovery, with mean recovery for the four silages used very close to 100%.

Resumo em Inglês:

ABSTRACT The effect of replacing wheat bran with spineless cactus (0, 25, 50, 75, and 100%) in sugar cane-based diets on the intake of nutrients, feeding behavior, and rumen digestibility of steers was assessed using digested samples collected from the omasum. Five crossbred steers (1/2 Holstein-Zebu) were fitted with cannulas in the rumen and then assigned to a 5 × 5 Latin square design. Samples of omasal digesta were collected for three days. Rumen was evacuated via the rumen cannula to determine the rumen pool of dry matter (DM), neutral detergent fiber (NDF), indigestible NDF (iNDF), intake (ki), passage (kp) and degradation (NDF) rates, and the passage of iNDF (kpi). Nutrient intake displayed a quadratic effect, with maximum intakes of DM (5.73 kg d−1), non-fiber carbohydrates (NFC, 4.63 kg d−1), and digestible organic matter (DOM, 3.45 kg d−1) estimated at the replacement levels of 54.63, 60.00, and 43.17%, respectively. The replacement levels showed no effect on feeding, rumination, or idle times. There was a linear increase in the total apparent and ruminal digestibility of CP as the spineless cactus content in the diet was increased. There was no effect on total and partial digestibilities of OM and NDF or on intestinal digestibility of CP. No effect was observed on the rumen pool of DM, NDF, or iNDF. Furthermore, ki, kp, NDF degradation, and iNDF passage rates displayed a quadratic effect, with higher concentrations estimated for replacement levels of 56.07, 56.12, 59.00, and 55.20%, respectively. Replacing 55% wheat bran with spineless cactus in sugar cane-based diets is recommended.

Resumo em Inglês:

ABSTRACT The objectives of this study were to evaluate the effect of forages with different nutritional values - specifically, corn silage (CS), sugar cane (SC), and sugar cane bagasse (SB) - in diets with crude glycerin, on carcass traits, meat quality, and fatty acid profile, using young Nellore bulls finished in the feedlot. Thirty young Nellore bulls with an initial average body weight of 416.70±24.74 kg were randomly assigned to three treatments containing different sources of forage. The carcass traits and variables related to meat quality of the Nellore young bulls were not significantly influenced by different sources of forage in diets with crude glycerin. The yellow color index was significantly greater in the fat of animals fed corn silage. Heptadecenoic fatty acid was significantly lower in the meat of animals fed sugar cane bagasse. The sources of forage in diets with crude glycerin did not influence the profile of saturated, monounsaturated, or polyunsaturated fatty acids in the longissimus muscle. Overall, our results indicate that none of the treatments changed the carcass and meat quality traits of Nellore young bulls finished in the feedlot. Thus, sugar cane and sugar cane bagasse could be used in feedlot as a viable forage alternative to corn silage.

Resumo em Inglês:

ABSTRACT The objective of the present study was to assess the effect of dietary supplementation of Omega-3 plus on some the physiological and biochemical traits in growing Baladi goats under hot summer conditions. Thirty-four growing male goats (4-5 months old) were randomly divided into two equal groups. Animals in group 1 were fed a concentrate feed mixture (CFM), which was the control group. Goats in group 2 (the experimental group) were offered Omega-3 plus (1,000 mg/animal day-1) (30% fish oil, containing 18% eicosapentaenoic acid and 12% docosahexaenoic acid + 100 mg wheat germ oil (0.22% tocopherols)) daily in addition to the basal diet for four months (the experimental period) during the hot summer season. Body weight (BW) changes of both groups were recorded monthly during the experiment. Blood samples were collected monthly, and total protein, immunoglobulin G (IgG), total cholesterol, triglycerides, liver enzymes (AST and ALT), blood urea nitrogen, serum creatinine, and thyroid hormones (T3 and T4) were estimated. A significant increase in the live BW of growing goats was recorded as a result of dietary supplementation of Omega-3 plus. Total protein, IgG, and T3 levels were higher than those obtained with control. In contrast, total cholesterol, triglycerides, urea, ALT, and AST levels were significantly reduced. The serum concentration of creatinine and T4 levels was indistinguishable from those of control. Addition of Omega-3 plus as a dietary supplement to growing goats under hot summer conditions increases their daily weight gain and improves their general physiological and biochemical status by decreasing total cholesterol, triglycerides, urea, ALT, and AST. It is thus suggested that Omega-3 plus should be used as a supplement in the growth period of goats.

Resumo em Inglês:

ABSTRACT A linear programming mathematical model was applied to a representative dairy farm located in Brazil. The results showed that optimization models are relevant tools to assist in the planning and management of agricultural production, as well as to assist in estimating potential gains from the use of integrated systems. Diversification was a necessary condition for economic viability. A total cost reduction potential of about 30% was revealed when a scenario of lower levels of diversification was contrasted to one of higher levels. Technical complementarities proved to be important sources of economies. The possibility of reusing nitrogen, phosphorus, and potassium present in animal waste could be increased to 167%, while water reuse could be increased up to 150%. In addition to economic gains, integrated systems bring benefits to the environment, especially with reference to the reuse of resources. The cost dilution of fixed production factors can help economies of scope to be achieved. However, this does not seem to have been the main source of these benefits. Still, the percentage of land use could increase up to 30.7% when the lowest and the highest diversification scenarios were compared. The labor coefficient could have a 4.3 percent increase. Diversification also leads to drastic transaction cost reductions.

Resumo em Inglês:

ABSTRACT The objective of the present study was to evaluate soil collected from a laying-hen farm and bird manure according to the season of the year and sampling site. Soil samples were taken at the poultry facility wall and at the distances of 15 m and 45 m from the building. Bird feces samples were collected inside the poultry house at the entrance and at 1/4 and 1/2 length of the building. Soil and bird feces samples were evaluated by bacteriological qualitative and quantitative analyses. The largest bacterial load was determined in the samples taken at the poultry facility wall in December/January. Soil microbial contamination degree was low. The highest bacterial count in bird manure was found in the samples collected at 1/2 length of the hen house at the end of December/January. The qualitative study of bird feces showed the presence of E. coli bacteria all through the research period and Enterobacter spp. in the samples taken from July until September. Microbial contamination of soil environment and bird feces is most likely to be affected by winter period as at that time the highest microbial population can be determined. This fact may be linked to the prevailing climatic and microclimatic conditions.

Resumo em Inglês:

ABSTRACT Genomic selection has been a valuable tool for increasing the rate of genetic improvement in purebred dairy cattle populations. However, there also are many large populations of crossbred dairy cattle in the world, and multi-breed genomic evaluations may be a valuable tool for improving rates of genetic gain in those populations. Multi-breed models are an extension of single-breed genomic models in which a genomic relationship matrix is used to account for the breed origin of alleles in the population, as well as allele frequency differences between breeds. Most studies have found little benefit from multi-breed evaluations for pure breeds that have large reference populations. However, breeds with small reference populations may benefit from inclusion in a multi-breed evaluation without adversely affecting evaluations for purebred performance. Most research has been conducted in taurine breeds, so additional research is needed to determine the value of multi-breed reference populations for composite and synthetic breeds that include both indicine and taurine cattle adapted to tropical climates.