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Vitamina E na produção e características da carcaça e da carne de cabritos ½ Boer-Saanen

Thu, 01 Jan 2015 00:00:00 GMT

Título: Vitamina E na produção e características da carcaça e da carne de cabritos ½ Boer-Saanen Autor(es): Possamai, Ana Paula Silva Abstract: The goal of this study was to evaluate the performance, carcass quantitative characteristics, shelf life and physicochemical characteristics of Longissimus dorsi muscle and the allometric growth of cuts and tissue of goat kids ½ Boer-Saanen fed diets with different levels of vitamin E. Thirty-five goat kids ½ Boer-Saanen were used, with an average age of 122 ± 3.57 days and initial body weight of 21 ± 2.85 kg, distributed in a completely randomized design in four treatments, being the control without addition of vitamin E, and other treatments containing 50, 150 and 450 mg of dl-α-tocopheryl acetate/kg of DM. The animals were weighed at the beginning of the study and each 14 days to monitor the body weight and make diet adjustment. When the average body weight reached 32 kg, the animals were fasted for 16 hours and subsequently slaughtered to obtain the carcass. Quantitative carcass characteristics were evaluated, and samples of the Longissimus dorsi muscle were taken to the physicochemical evaluations and visual assessment of meat shelf life. The left half carcass was sectioned into five anatomical regions, as follows: neck, shoulder, ribs, loin and leg. To evaluate the allometric growth of the cuts and tissues, the cuts: shoulder, loin and leg were dissected and separated into following tissues groups: total fat, muscle and bone. There were no treatment effects on performance and carcass quantitative characteristics of the animals supplemented with vitamin E in diet, however there was effect of gender on performance and carcass characteristics of the animals, where males showed better results. To the physicochemical characteristics of Longissimus dorsi muscle, there were no effects of treatments in color, pH and muscle shear force. However, there was a positive linear effect for the moisture content and cooking loss, and negative linear effect on crude protein and total fat content in Longissimus dorsi muscle of the animals supplemented with vitamin E in diet. In the fatty acid concentration in Longissimus dorsi muscle, improvements were observed in the fatty acid profile, with quadratic effect for myristic, conjugated linoleic acid and arachidonic fatty acids, and for the sum of poly-unsaturated fatty acids and the ratio polyunsaturated fatty acid: saturated fatty acid, and a negative linear effect for the palmitoleic fatty acid. There was a reduction in lipid oxidation in the meat days of storage and increased incorporation of vitamin E in muscle of the animals that consumed diets supplemented with vitamin E. The shelf life of meat was influenced by vitamin supplementation in animal diet and showed greater survival time of meat in chemical evaluation by the method of thiobarbituric acid reactive substances and the visual evaluation method for consumers, wherein the chemical method was more accurate to assess the prediction of shelf life. There were diet effects on allometric growth of carcass commercial cuts of animals supplemented with vitamin E, and on the development of tissues (muscle, fat and bone) in the main commercial cuts of the goat kids' carcass. Vitamin E can be used to fed ½ Boer-Saanen goat kids in levels up to 150 mg, without affecting the productive performance of the animals, showing improvements in chemical composition of Longissimus dorsi, in the vitamin E incorporating in muscle tissue, reducing lipid oxidation, better consumer acceptance of meat supplemented and proper development of cuts and tissues cuts of animals carcasses.

Vitamina A na alimentação do Pacu Piaractus mesopotamicus HOLMBERG, 1887

Sat, 01 Jan 2011 00:00:00 GMT

Título: Vitamina A na alimentação do Pacu Piaractus mesopotamicus HOLMBERG, 1887 Autor(es): Signor, Arcangelo Augusto Abstract: Two studies were carried out to evaluate vitamin A supplemented by retinyl acetate in pacu Piaractus mesopotamicus diets. In experiment I, 240 juveniles with an average initial weight of 17.55±3.22g were distributed randomized in 20 aquariums (500L), with five treatments and four replications. The vitamin A supplementation in diets was 0; 3.000; 6.000; 9.000 and 12.000 UI vitamin A/kg of diet supplemented by retinyl acetate (1.000.000 UI/g vitamin A), included in mineral and vitamin supplement. The juveniles were fed at 8:00; 11:00; 2:00 and 5:00, until apparent satiety. Effects of vitamin A supplementation in diets on productive performance was evaluated, as well as body yield, carcass chemical composition, hematologic and histologic variables of the liver. No difference was observed on feed conversion rate, survival, final length and factor condition for pacu fed with diets containing different levels of vitamin A. A quadratic effect was observed on parameters of final weight, daily weight gain, feed efficiency with better results for 6.666; 6.583 and 5.555 UI vitamin A/kg diet levels, respectively. There were no differences in carcass yield, carcass chemical composition, blood parameters and liver histology of pacu. In commercial diets formulated with ingredients for juveniles of pacu Piaractus mesopotamicus, reared in a recirculation system, it is recommended a supplementation of 5.555 UI vitamin A/kg diet, providing the best results in daily weight gain. For experiment II, 2.000 fish were used with initial average weight of 66.93±15.03 g and medium initial length of 14.59±1.07 cm, completely distributed at random in 20 cages of 5.0 m3 (five treatments and four replications with 20 fish/m3). The vitamin A supplementation in diets was by retinyl acetate (1.000.000 UI/g of vitamin A) included in mineral and vitamin supplement for diets presenting 0; 3.000, 6.000, 9.000 and 12.000 UI of vitamin A/kg of diet. The juveniles were fed at 8:30, 1:30 and 5:30 until apparent satiety. The effects of vitamin A supplementation in diets were evaluated on growth performance, body yield, carcass chemical composition, hematologic variables, vitamin A concentration and lipids in liver. No influence was observed on diet in vitamin A levels on growth performance in carcass yield, carcass chemical composition, blood parameters and lipids, however there was observed a higher concentration of vitamin A in liver. The vitamin A supplementation in diets for pacu juveniles reared in cages did not influence on growth performance, carcass yield, carcass chemical composition, blood parameters and liver lipids, however, there are influences in the vitamin A retention on the liver of fish.

Vitamina A e vitamina D3 na alimentação de frangos de corte

Fri, 01 Jan 2016 00:00:00 GMT

Título: Vitamina A e vitamina D3 na alimentação de frangos de corte Autor(es): Guerra, Ana Flávia Quiles Garcia Abstract: Four experiments have been conducted to evaluate the vitamin A and D3 on performance, carcass yield, meat and bone quality and immune system of broilers feed. In Experiment I, in order to assess levels of vitamin D3 metabolites on performance, bone quality and intestinal morphometry1,344 Cobb male chicks were distributed in a factorial 2x4, with two metabolites of vitamin D3 (D3 and 1.25 (OH)2D3) and four levels (200, 950, 1,700 and 2,400 IU vitamin D3/kg of diet), with six replicates of 28 birds each. There was no interaction (P>0.05) among metabolites and vitamin D3 levels for any of the variables evaluated. Feed intake and weight gain (1 to 21 days) presented a quadratic effect (P<0.05) in which the higher feed intake and better weight gain were estimated at 1,772.39 and 1,760.14 IU of vitamin D3/kg, respectively. For relative weight of organs at 7 days there was an increasing linear response for small intestine in relation to vitamin D3 in the diet, and at 21 days the relative weight of liver presented a quadratic response with higher weights estimated at 1,811.40 IU/kg. Among metabolites, vitamin D3 had better (p<0.05) weight gain, higher (p<0.05) intestine length and lower (P<0.05) liver weight on day 21 compared to metabolite 1.25 (OH)2D3. Regarding the bone variables, there was a positive linear effect on ash (P<0.05) at days 7 and 21 due to the levels of vitamin D3 and quadratic effect on bone strength, in which the best result was obtained at 1,768.49 IU/kg. The percentages of calcium in the ash at day 7, of phosphorus in the ash and serum calcium at day 21 were increasing linearly influenced due to vitamin D3 levels. The other variables were not affected (p> 0.05) by different levels of vitamin D3. In Experiment II, in order to evaluate the vitamin D3 metabolites (25(OH)D3; 1,25(OH)2D3 and 1α(OH)D3) on top associated with the best level of vitamin D3 obtained in Experiment I on performance and bone quality, 625 one-day-old Cobb male chicks were distributed in a completely randomized experimental design with five treatments (T1-2375UI D3 / kg); T2-1780UI / kg D3 / kg; T3 1780 IU / kg + D3 100mg of 1,25(OH)2D3 / kg; T4 1780UI D3 / kg + 0,069kg 25(OH)D3 / kg and T5-1780UI D3 / kg + 500 mg of 1α(OH)D3 / kg), with five replicates and 25 birds each. There was no effect (P>0.05)of vitamin D3 metabolites on performance variables. There was effect of different sources of vitamin D3 on the activity of alkaline phosphatase enzyme, which was more active (P<0.05) due to supplementation of active analogue of vitamin D3, 1α(OH)D3. Other factors were not affected by vitamin D3 metabolites. The supplementation of vitamin D3 level of 1,772.39 IU/kg of diet, regardless the metabolite for broilers in the initial phase, enabled maximize weight gain of birds and increased bone strength. However, the administration of various metabolites of vitamin D3 on top did not improve the use of vitamin D3. In Experiment III, with the objective of evaluate vitamin A and D3 in broilers feed on performance, carcass yield and meat quality 1.520 one-day-old Cobb male chicks were distributed in a factorial scheme 5x4, with five levels of vitamin A (0, 9,000, 18,000, 36,000 and 54,000 IU) and four different levels of vitamin D3 (200, 950, 1,700 and 2,450 IU), with four replicates and 19 birds each. There was no interaction (p>0.05) among levels of vitamin A and vitamin D3 for performance, carcass yield and meat quality. Vitamin A supplementation affected increasing linearly the weight gain and feed intake of birds from 1 to 21 days and quadratically in the total period (1-to-42 days) with better weight gain and higher feed intake at levels 35,193.58 and 37,016.72 IU Vitamin A/kg. However, there were no differences (p>0.05) for feed conversion in any periods evaluated. The carcass yield was not affected by vitamin A levels, however for breast and thighs + drumsticks yield (%) we observed quadratic effect (p<0.05), with better yields estimated at 29,430.75 and the 30,630.83IU of vitamin A/Kg. Additionally, vitamin A presented influence on yellow color intensity of breast meat and thighs + drumsticks. Vitamin D3 addition in diets affected increasing linearly the weight gain and feed intake (p<0.05) from 1 to 21 days and showed quadratic effect between 1 and 42 days, with higher weight gain estimated in 1,841.70 IU of vitamin D3/kg and higher feed intake at 1,900.32 IU of Vitamin D3/kg. The feed conversion was not affected (p>0.05) by levels of vitamin D applied. Similarly, carcass yield presented the same trend of weight gain, presenting better breast yield (%) and thigh + drumstick (%) on the estimated levels of 1,663.27 and 1,763,33 IU of vitamin D3/kg, respectivelly. Vitamin D3 had a quadratic effect (P<0.05) on the intensity of red on thigh meat, with lower level estimated at 1,559 IU vitamin D3/kg Within the assessed levels there is no interaction among vitamin A and vitamin D3 on performance, carcass yield and cuts and meat quality. Supplementation of independent vitamin A levels of 54,000 IU/kg from 1 to 21 days and 35,195.38 IU/kg from 1 to 42 days, and 2,400 IU/kg of vitamin D3 from 1 to 21 days and 1,841.70 IU/kg from 1 to 42 days allow performance improvement without harming the carcass yield and meat quality. In Experiment IV, in order to evaluated vitamins A and D3 in broilers feed on bone quality and immune system, 1,520 one-day-old Cobb male chicks were distributed in a factorial scheme 4x5, with four different levels of vitamin D3 (200, 950, 1,700 and 2,450UI) and five levels of vitamin A (0, 9,000, 18,000, 36,000 and 54,000 IU), with four replicates and 19 birds each. There was interaction (p<0.05) for bone ash (%) on day 7, with the best mineral deposition at the level of 36,000 IU of vitamin D3/kg associated with 200 IU of vitamin D3/kg. For diameter, length, seedor index, bone strength and concentration of calcium and phosphorus, there was no interaction (p>0.05) among the vitamins A and D3. Vitamin A supplementation had a quadratic effect (p<0.05) on phosphorus in the tibia (%) on the 21st day, with higher levels of this mineral in the estimated level of 29,607.23 IU of vitamin A/kg and increasing linearly (p<0.05) the serum phosphorus (21 days) and the bone length (42 days). With supplementation of vitamin D3 levels the bone strength at 7 and 21 days showed quadratic behavior (p<0.05) with higher resistances at estimated levels of 1,937.48 and 2,011.57 IU of vitamin D3/kg and decreasing linear effect (p<0.05) at 42 days for total epiphyseal area and cartilage zone, confirming the importance of vitamin D3 in bone metabolism and in the prevention of tibial dyschondroplasia. For serum antibodies against Newcastle disease, vitamin D3 showed increasing linear effect, elevating the response as levels of vitamin D3 increased. For vitamin A, the antibody title against Newcastle disease showed a quadratic behavior (p<0.05), with lower response for estimated level of 23,763.78 IU/kg. Supplementation of vitamin A, independently, at level of 29,607.23 IU/kg resulted in better mineral deposition in the bone and vitamin D3 supplementation in level of 2,011.57 IU/kg resulted in the best bone strength and prevention of tibial dyschondroplasia. The concentrations of vitamin A and D3 used did not interfer the immunological system.

Vesículas de membrana : um componente inexplorado no rúmem com capacidade de degradação de proteínas, carboximetilcelulose e amido

Thu, 01 Jan 2015 00:00:00 GMT

Título: Vesículas de membrana : um componente inexplorado no rúmem com capacidade de degradação de proteínas, carboximetilcelulose e amido Autor(es): Prado, Rodolpho Martin do Abstract: Membrane vesicles production is a ubiquitous process in Gram-negative and rampositive bacteria. Research on membrane vesicles increased during the last 10 years, but it is mainly focused on human pathogens. Also, in most studies only bacterial pure cultures are investigated. With the advance of proteomics, several new functions are now associated with membrane vesicles. Yet, so far no study has isolated membrane vesicles from rumen fluid, or assessed their capacity to hydrolase substrate. Thus, as a first study, outer membrane vesicles were isolated from an axenic culture of Prevotella ruminicola, using a protocol used to isolate outer membrane vesicles from pathogenic bacteria, and hydrolytic activity from the samples was assessed. The protocol was successfully employed as no bacterial contamination was observed on cross-section transmission electron microscopy. The protein profile from the whole culture, washed culture, outer membrane vesicle-free supernatant, and outer membrane vesicles were distinct as observed on SDS-PAGE. Proteolytic activity was assessed on gelatin zymograms and outer membrane vesicle samples had distinct and clearer bands compared to whole culture, washed culture, and outer membrane vesicle-free supernatant. Protease inhibitors to assess protease classes were added to the samples but no clear effect could be observed. Furthermore, no activity could be observed on carboxymethylcellulose and starch zymograms. Although a greater enzymatic activity was expected, results provide evidence that some proteolytic enzymes from P. ruminicola are selectively loaded into outer membrane vesicles from this bacterium. As a second study, membrane vesicles were isolated using rumen liquor and particulate matter from the rumen. Fractions using solid-attached bacteria and liquid-associated bacteria were used to further improve membrane vesicle characterization. Three cows were sampled but only samples from one cow were imaged with negative staining transmission electron microscopy. Protein profiles of samples were similar when assessed on SDS-PAGE, but proteolytic activity was diverse on gelatin and casein zymograms. Furthermore, activity on carboxymethylcellulose and starch zymograms was diverse across the samples. These results provide evidence that membrane vesicles in the rumen have been overlooked as in some cases more activity was observed in vesicle samples compared to within the microorganisms. Understanding fundamentals from microbiome is key to improve feed use in ruminants and research using membranes vesicles isolated from the rumen might add knowledge on rumen microbiome function.