Camila Celeste Brandão Ferreira Ítavo

Desempenho produtivo, características de carcaça e avaliação econômica de bovinos cruzados, castrados e não-castrados, terminados em pastagens de Brachiaria decumbens

The effect of the castration on the productive performance and carcass characteristics was studied, as well as, the economic evaluation of finished bovines raised on Brachiaria decumbens pastures. Eight Canchim-Nellore steers aging 14-months-old were used, being four castrated and four non-castrated, averaging 273.2kg body weight. It was used a completely randomized design with four repetitions per treatment. The animals received 0.7% of their body weight of proteic-energetic supplement and were slaughtered at 26 months of age. The weight at slaughtering and the average daily weight gain differed between castrated and non-castrated, averaging 441.0 and 482.2kg, and 0.6 and 0.7kg/day, respectively. No effects of the castration on carcass characteristics were observed, except for weight of hot carcass, 252.3 versus 229.9kg; meat color, 3.25 versus 4.50 points; and subcutaneous fat thickness, 0.6 versus 1.4mm; respectively, for non-castrated and castrated. The profitabilities per animal and hectare were 14.5 and 15.8% for non-castrated and 4.5% and 5.8% for castrated, respectively. It is suggested the raised of non-castrated bovines supplemented on Brachiaria decumbens pastures.

Sugar cane treated with calcium hydroxide in diet for cattle: intake, digestibility of nutrients and ingestive behaviour

The objective of this work was to evaluate, in bovines, the intake and apparent digestibility of nutrients, ingestive behaviour and content of total digestible nutrients (TDN) of diets based on sugar cane treated with calcium hydroxide. It was used four cows with average body weight of 412.06 kg ± 37.3 kg. The study included inclusion of calcium hydroxide at the doses 0, 8, 16 and 24 g/kg of sugar cane in natural matter basis fed in diets with 65% of roughage and 35% on concentrate, based on dry matter (DM). It was used a 4 × 4 Latin square experimental design with four treatments and four periods. Calcium hydroxide doses affected nutrient intake: DM intake was 7.88 kg/day at the dose of 14.99 g of calcium hydroxide, organic matter (OM) intake was 6.75 kg/day at 10.94 g; intake of neutral detergent fiber (NDF) of 3.33 kg/day with a dose of 13.93 g; and intake of acid detergent fiber (ADF) of 2.12 kg/day with a dose of 10.51 g. Digestibility coefficients showed a quadratic effect for doses of inclusion of calcium hydroxide. Dry matter digestibility was 72.88% with a dose of 11.65 g of calcium hydroxide, OM digestibility was 75.12% with 12.09 g; NDF digestibility was 58.67% with 12.11 g; ADF digestibility was 52.97% with 9.36 g and TDN digestibility was 71.42% with 10.92 g. There was no effect of the treatment for activities of rumination and total idle. Chewing time, number of bolus chewed and time for rumination of each bolli presented effect. Calcium hydroxide enabled greater intakes and digestibility of nutrients, especially from the cell wall, favoring the use of nutrients from the diet containing sugar cane, recommending a dose of 8-12 g.

Características de carcaça, componentes corporais e rendimento de cortes de cordeiros confinados recebendo dieta com própolis ou monensina sódica

This work was aimed at evaluating the effects of green propolis, brown propolis and sodic monensin aditives on the carcass characteristics by means of ultrasound and after-slaughter measures such as carcass non-components and yield of retail products from lambs finished in feedlot system. Thirty-two male lambs, with eight animal per treatment, were feedlot during 64 days. The animals were fed a diet with roughage:concentrate ratio of 50:50, composed of Tifton 85 hay grass (Cynodon spp.) and commercial concentrate. The experimental design was a randomized block design, with eight animals randomly assigned according to weight and the following treatments: control, diet without additive, green propolis, brown propolis and sodic monensin. The true, hot and commercial carcass percentage did not differ between treatments, with means of 54.97; 44.89 and 41.81%, respectively. Carcass non-components and yield of retail products were not influenced by treatments. The methodology used in the determinations affected the LEA and FT measures, so that the traditional method, obtained through measures in the carcass presented the highest averages for LEA (12.14 vs. 9.08 cm2) and lowest for FT (2.42 vs. 2.69 mm). The correlation between the of loin eye area (LEA) measures of the carcass with those obtained by ultrasound scan was 0.8597. The additives did not influence the carcass characteristics, non- components and yield of retail products from lambs finished in feedlot system. The performance of LEA and marbling ultrasound measures can be used in the in vivo carcass evaluation in sheep.

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.

Effects of dietary brown propolis on nutrient intake and digestibility in feedlot lambs

The present study tested brown propolis in crude or extract form as a feed supplement for feedlot lambs to identify the type that most improves in vivo nutrient digestibility. Digestibility was assessed by both total fecal collection and internal markers and the results obtained by these techniques were compared. The completely randomized design was used to compare feed intake and nutrient digestibility of 24 male lambs aged seven months among four dietary treatments (crude brown propolis, propolis ethanol extract, monensin sodium, and control). Methods of feces collection were compared using a completely randomized split-plot design, with experimental diets corresponding to the main factor and the methods to estimate fecal production as the sub-factor. The diets had a roughage:concentrate ratio of 50:50, with Tifton-85 bermudagrass hay (Cynodon spp.) as roughage, and ground corn, soybean meal and minerals as concentrate. The lambs fed diets with crude propolis had higher feed intake than those fed diets containing monensin sodium. The different diets did not affect dry matter, organic matter, crude protein, neutral detergent fiber, or acid detergent fiber digestibility, but crude propolis supplementation provided higher ether extract digestibility than monensin sodium. Nutrient digestibility, as indicated by indigestible neutral detergent fiber, indigestible acid detergent fiber and sequentially-determined indigestible acid detergent fiber, was lower than that found with the fecal collection method. The addition of brown propolis has the same effect as monensin, but neither maximized nutrient availability in the diet of feedlot lambs at 7 months of age. Digestibility assessment using the internal markers indigestible neutral detergent fiber, indigestible acid detergent fiber and sequentially-determined indigestible acid detergent fiber is not an efficient method compared with total feces collection.

Green propolis extract as additive in the diet for lambs in feedlot

The objective of this paper is to assess the effects of the inclusion of different levels of green propolis extract in the diet of lambs in feedlot on ingestive behavior, nutrients digestibility, physiological parameters and performance. Eight lambs were distributed in double Latin Square with four treatments, corresponding to the inclusion levels (4, 8, 12, 16 mL) of green propolis ethanolic extract (30 g of ground crude propolis was infused in a 100-mL hydroalcoholic solution, 700 mL/L). The diets were composed of Brachiaria brizantha cv. MG5 hay and a commercial concentrate (roughage:concentrate ratio was 50:50) in a dry matter basis. No effect was observed on dry matter (31.2 g/kg of BW), crude protein, ether extract, neutral detergent fiber, non-fibrous carbohydrates and total digestible nutrients content (TDN) intakes. No significant effect was seen on the digestibility coefficients, presenting an average of 65.94% of TDN. The green propolis extract levels do not have a significant effect on behavior or physiologic parameters. Seeking to maximize feeding efficiency, the inclusion of 7.60 mL/day (2.1189 mg of dry matter and 0.1123 mg of flavonoids) of green propolis extract in the diet of lambs in feedlot is recommended.

Identification of lamb flocks susceptible and resistant against Brachiaria poisoning

This study was designed to assess the influence of genetic resistance against brachiaria poisoning in sheep. Two groups of sheep, one identified as susceptible (formed by two ewes and one ram) and the other as resistant against brachiaria poisoning (formed by three ewes and one ram) were selected. Sheep considered susceptible were those that presented clinical signs of brachiaria poisoning at any time of their life; resistant sheep were those that even raised on Brachiaria spp. pastures, did not developed any sign of the poisoning during their life. The offspring of the two flocks (15 lambs from the sensitive flock and 9 lambs from the resistant flock) were placed into brachiaria pasture (initially Brachiaria decumbens and B. brizantha,and only B. decumbens after weaning) and followed up during two years (2013-2014). The determination of protodioscin levels in B. decumbens pasture was performed only in 2014 and revealed significant amounts of the toxic principle. Eleven lambs of the susceptible group were affected to some degree of brachiaria poisoning and six died; no lamb of the resistant group was affected. Clinical signs consisted of varying degrees of subcutaneous edema of the face and, erythema and loss of hair of the ears, crusts on the skin of ears, around the eyes and on planum nasale, scar deformation of the ears, and bilateral ocular discharge; affected lambs also sought for shadowy shelters and they were poor doers. Several sheep recovered from the condition and then relapsed. Necropsy findings in six lambs included pale mucous membranes, emaciation, dermatitis, scar deformation of the ears, large yellow livers with marked lobular pattern, and moderate infestation by Haemonchus contortus. Histologically the liver lesions were similar in all necropsied lambs but with varying degrees of severity; they were consistent with brachiaria poisoning and included architectural disruption of hepatocellular trabecula, clusters of foamy macrophages occasionally forming multinucleated giant cells, swollen and vacuolated hepatocytes, crystals or negative images of crystals in the biliary system, bilestasis, bile duct proliferation and lymphoplasmacytic infiltrate in portal triads. The skin lesions were those of photodermatitis and included epidermal necrosis, hyperkeratosis and dermal neutrophilic infiltrate. The results of this study allow to conclude that there is a genetic related resistance to brachiaria poisoning in sheep since the progeny of resistant sheep did not manifest the poisoning. The use of resistant flocks in brachiaria pastures is suggested as a valuable option for the prevention of brachiaria poisoning in sheep.

Ácidos graxos voláteis no rúmen de vacas alimentadas com diferentes teores de concentrado na dieta

The influence of concentrate levels from the diet on the content of volatile fatty acids in rumen fluid of cattle was evaluated. Four rumen fistulated crossbred cows, weighting around 442.15kg, were distributed in 4x4 Latin square schedule, divided into four periods of 14 days, 11 for adaptation and three for data collection. Corn silage was used as roughage, and corn, sorghum, soybean meal, soybean hulls, protected fat and urea, as concentrate. Diets were formulated with 13% crude protein (CP), using the proportions of 30, 40, 50 and 60% concentrate. There was no influence of treatment for the following acid concentrations: acetic, isobutyric, butyric, isovaleric and valeric. The propionic acid content and the ratio acetate: propionate showed values of 8.44 and 8.14 hours after feeding, respectively. The total fatty acids were not affected by treatments, with maximum concentration at 7.68 hours after feeding, with minimum pH values between six and nine hours. Diets containing up to 60% of concentrate in dry matter did not influence the concentrations of rumen volatile fatty acids.

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.

Resíduo da extração de própolis como inibidor bacteriano in vitro

This study aimed to evaluate the effect of residues extraction hydroalcoholic of propolis, green and brown, on the development of Gram-positive and Gram-negative bacteria. The crude propolis was obtained from “Companhia da Abelha” in Contagem, Minas Gerais. The green propolis derived from “alecrim-do-campo” (Baccharis dracunculifolia), and the brown propolis derived from “alecrim-do-campo” (B. dracunculifolia) and “assa-peixe” (Vernonia polyanthes). We used five levels of inclusion (0; 0.625; 0.125; 0.25; 0.5g) of the residue, and control for the inoculum (CI) and six bacterial strains, two of which are Gram-positive and four Gram-negative. The method used was to count colony-forming units in petri dishes (pour plate). Among the Gram-positive bacteria, the greatest inhibitory effect was detected for Staphylococcus aureus strains, and increased susceptibility was observed for Escherichia coli among Gram-negative bacteria. There was antimicrobial effect of the residue of the propolis extract on S. aureus and S. intermedius. The residue of brown propolis extract showed greater inhibition for S. intermedius only in 0.5 and 0.25g of residue inclusion levels. There was no effect of residues extraction hydroalcoholic of propolis, green and brown on the growth of Pseudomonas. The residues of the extraction of propolis green and brown acted as inhibitors of growth of Staphylococcus aureus, Staphylococcus intermedius and Escherichia coli, and to a lesser extent Salmonella and Klebsiella. The residue has greater inhibitory effect on Gram-positive bacteria.