Luís Carlos Vinhas Ítavo

Calorimetry, chemical composition and in vitro digestibility of oilseeds.

The objective of the study was to determine the quality of sunflower, soybean, crambe, radish forage and physic nut, by measuring chemical composition, in vitro digestibility and kinetics of thermal decomposition processes of mass loss and heat flow. Lipid was inversely correlated with protein of whole seed (R = -0.67), meal (R = -0.95), and press cake (R = -0.78), and positively correlated with the enthalpy (ΔH) of whole seed. Soybean seed and meal presented a high in vitro digestibility but poor energy sources with ΔH averaging 5907.5 J/g and 2570.1J/g for whole seed and meal, respectively. As suggested by the release of heat, measured by ΔH, whole seeds of crambe (6295.1J/g), radish forage (6182.7 J/g), and physic nut (6420.0 J/g) may be potential energy sources for ruminant animals. The thermal analysis provided additional information besides that obtained from the usual wet chemistry and in vitro measurements.

Effect of creep-fed supplement on the susceptibility of pasture-grazed suckling lambs to gastrointestinal helminths

This study evaluated the effect of creep feeding a protein supplement on the susceptibility of suckling lambs to infection with gastrointestinal helminths. Male and female lambs were grazed on Brachiaria spp. pastures next to their mothers. Animals were allocated to one of two treatments: creep feeding (261g/d) and control (no supplementation). The trial period was the suckling of lambs during two years of study: May-October 2013 and March-July 2014. Supplementary creep feeding of lambs improved animal performance (P<0.05). Creep-fed lambs reached 18kg body weight in 64 d, but unsupplemented lambs required 77 d to reach the same weight. Lambs were susceptible to helminth infection during lactation; lambs in both treatments had high fecal egg counts (FECs), with means >1000 eggs per gram, as early as 45days of age, when the daily grazing time per animal increased. Creep feeding reduced the FECs of suckling lambs >60days of age in infections dominated by Haemonchus contortus. Totals of 20 and 48 anthelmintic treatments were administered to the supplemented and unsupplemented animals, respectively. The effect of this variable, however, was significant (P<0.05) only after 60days, when nine and 28 treatments had been administered to the supplemented and unsupplemented lambs, respectively. The number of strongyloid larvae recovered from the paddock did not differ significantly (P >0.05) between the two treatments, indicating similar challenges by infective larvae to both groups. The supplementation of lambs by creep feeding can thus be a strategy for the sustainable control of helminth infection, because it reduces the dependence on anthelmintic treatment.

Atividade antibacteriana in vitro da própolis marrom

The aim of this study was to evaluate the in vitro antibacterial activity of brown propolis, by determining the minimum inhibitory concentration (MIC). The alcoholic extract of propolis was obtained from 35g of crude propolis macerated in 65mL of cereals alcohol. Dilutions of propolis extracts used were: 75mg/mL; 56.4mg/mL; 37.5mg/mL; 18.9mg/mL; 9.3mg/mL; 4.5mg/mL, and 2.25mg/mL. Thirty-two Gram-positive bacteria isolates were used: Rhodococcus equi, Staphylococcus aureus, Staphylococcus hyicus, Staphylococcus spp. and Streptococcus spp.; and the thirty-two Gram-negative bacteria isolated were: Enterobacter agglomerans, Escherichia coli, Klebsiella pneumoniae, Klebsiella sp., Pseudomonas aeruginosa, Pseudomonas sp., Salmonella sp., and Serratia rubidaea, obtained from infectious clinical processes of domestic animals, and stored in the Laboratory of Bacteriology of FAMEZ/UFMS. The brown propolis extract showed antibacterial activity with MIC ranging from 2.25 to 18.9mg/ml for Gram-positive bacteria and 4.5 to 18.9mg/ml for Gram-negative bacteria, and bacteria from cattle and dogs were more resistant. It was concluded that brown propolis has antibacterial action, but the effect depends on the species of the bacterium and its origin.

Calorimetry, chemical composition and in vitro digestibility of sugarcane treated with calcium hydroxide

Abstract. Sugarcane is a source of roughage in animal feeding. It presents high production per unit of cultivated area, relatively easy cultivation and low cost of production per hectare, and better quality and a high dry matter (DM) yield in periods when forage is scarce. This study aimed to evaluate the effect of increasing levels of calcium hydroxide (Ca(OH)2) in sugarcane forage on chemical composition, in vitro digestibility values of DM, neutral detergentfibre (NDF) and acid detergent fibre (ADF), and kinetics of thermal decomposition processes of weight loss and heat flow. Sugarcane was collected close to the ground and 50-kg heaps of the fresh material were formed and mixed with four doses of Ca(OH)2 (0, 8, 16 and 24 g kg–1 sugarcane). Concentrations of NDF and ADF decreased linearly with increasing amount of Ca(OH)2, whereas concentration of hemicellulose increased linearly. In vitro digestibilities of DM, NDF and ADF were enhanced in a quadratic manner with increasing amounts of Ca(OH)2. The release of heat, measured by ΔH, increased linearly with increased Ca(OH)2 levels, likely due to enhanced digestibility of the fibre components. Weight loss decreased linearly between 272.2°C and 397.7°C with increased amounts of Ca(OH)2 added to sugarcane, likely due to changes in cellulose structure, which became denser and thermodynamically more stable than native cellulose following the alkaline treatment. Calcium hydroxide changed chemical composition and digestibility of the fibrous fraction of sugarcane, resulting in better nutritional value. The greatest release of heat and highest in vitro digestibility of fibre were observed when adding 15.2 g Ca(OH)2 kg–1 sugarcane; therefore, this dose is recommended to enhance the nutritive value of sugarcane as ruminant feed.

Evaluation of internal and external markers to estimate faecal output and feed intake in sheep fed fresh forage

The objectives of the present study were to estimate dry-matter intake and output of faeces using two external and four internal markers in sheep fed Brachiaria brizantha cv. Marandu on an ad libitum basis over 3- and 5-day periods. Six sheep fitted with ruminal cannulas were randomly assigned in a crossover design experiment to receive either of two treatments of external markers, namely titanium dioxide (TiO2) and chromic oxide (Cr2O3). Faecal output was obtained by total faecal collection and faecal grab sampling. Faeces were collected for 3- or 5-day periods, and, for each collection period, two sampling methods were compared; grab samples were collected directly in the rectum once daily, and a second sample was taken at the same time directly in faecal collection bags after having determined the daily total output of faeces. Faecal concentrations of the internal markers, indigestible dry matter, indigestible neutral detergent fibre, indigestible acid detergent fibre and indigestible acid detergent lignin (iADL), were determined. Faecal output was not accurately predicted with indigestible dry matter, indigestible neutral detergent fibre, indigestible acid detergent fibre and iADL. Dry-matter intake was predicted with iADL and TiO2 when faeces were collected for 5 days as grab samples once daily, or as total collection and with Cr2O3 when faecal grab samples were collected for 5 days. The results using external markers indicated that TiO2 is not a marker equivalent to Cr2O3 for estimating intake and faecal output. TiO2 was the only external marker to accurately estimate faecal output, independent of the method (total or grab) and time period (3 or 5 days) used; this suggests that TiO2 is the best marker tested for predicting the faecal output of sheep that are fed a diet of fresh Brachiaria brizantha (cv. Marandu) grass ad libitum.

Intake, feeding behaviour, digestibility, performance, carcass characteristics and meat quality of lambs fed different levels of semi-purified glycerine in the diet

ABSTRACT The aim of this study was to evaluate the effect of different inclusion levels of semi-purified glycerine in the diet of feedlot lambs on feeding behaviour, nutrient intake and digestibility, carcass characteristics, meat quality and in vitro degradability. Thirty-two Dorper × (Texel × Suffolk) crossbred intact male lambs (22.2 ± 5.51 kg) were fed glycerine (90% purity) at 0, 120, 240 or 360 g/kg dry matter (DM) in a total mixed ration with a roughage to concentrate ratio of 40:60 for 84 d. In vitro degradability was not affected by glycerine supplementation. Feeding behaviour and digestibility of DM, crude protein and fibre and production performance were similar among treatments. Ether extract digestibility was lower at the highest inclusion level. Glycerine level had no effect on ruminal pH, carcass characteristics and meat quality, except for subcutaneous fat thickness which was lower for lambs fed glycerine at 240 and 360 g/kg DM. Scores for unpleasant taste, unpleasant odour, succulence and softness of meat were not affected by dietary glycerine level. These data suggest that there are no adverse effects on carcass quality and performance when semi-purified glycerine is provided up to 360 g/kg DM in the diet of growing lambs fed a forage to concentrate ratio of 40:60.

Leather quality of beefalo-Nellore cattle in different production systems

The aim was to compare the effects of two production systems on performance, carcass traits and physical-mechanical characteristics of leather from Beefalo-Nellore steers and heifers and to determine if the response to the production system was similar for both genders. A total of 40 Beefalo-Nellore cattle, 20 steers and 20 heifers, were evaluated. Animals were divided into two production systems: slaughtered at 15 (intensive system) or 26 (extensive system) months of age. In the intensive system, all animals received a ration containing 600 g/kg corn silage and 400 g/kg concentrate. In the extensive system, animals were kept on a pasture predominantly based on Brachiaria sp. and supplemented with 2 kg/day concentrate. In the intensive system, there was no difference in slaughter weight (470 kg body weight) between steers and heifers but steers in the extensive system had greater slaughter weight than heifers (463 and 428 kg body weight, respectively). Leather weight was higher for animals in the intensive than extensive system but there was no difference in leather weight once excess fat was removed. Leather quality from Beefalo-Nellore cattle slaughtered at 15 or 26 months of age is similar although carcass yield is higher for cattle slaughtered at a younger age.

Terminação de novilhos Nelore, castrados e não castrados, em confinamento com dieta alto grão

This study aimed to evaluate the finishing Nellore steers castrated and no-castrated in feedlot receiving high-grain diet through the nutrients intake, productive performance and economic viability of the diet. 180 Nellore animals were divided into two treatments (castrated and no-castrated), with 90 animals per treatments, with an average initial weight of 415.64kg, receiving high-grain diet with 85% corn grain and 15% supplement mineral-protein-energy. The experimental period was 63 days with 15 days for adaptation diets and 48 days of feedlot. Was no significant effect on intake of nutrients (P < 0.05), presenting a mean intake of dry matter (DM) of 7.60 and 7.96kg for castrated and no-castrated. Effects were observed for productive performance as a function of sex condition (castrated and no-castrated). The not castrated animals had higher (P < 0.05) slaughter weight, total weight gain, hot carcass weight, carcass yield and better feed conversion when compared to castrated animals finished in feedlot receiving high-grain diet. Castrated animals have a higher fat thickness that animals no-castrated, 4.80 and 3.40mm, respectively. The no-castrated animals showed profit margin lucre/animal of R

Combinações de fontes de nitrogênio não proteico em suplementos para novilhos Nelore em pastejo

256.00 and R

Destinação dos resíduos sólidos como sustentabilidade no meio rural

202.80 for castrated. Receiving the termination of Nellore steers in a feedlot is recommended high-grain diet. The no-castrated animals showed greater weight gain and profit in the feedlot finishing system receiving high-grain diet.