Vitamina A e vitamina D3 na alimentação de frangos de corte

• Ano de defesa: 2016
• Autor(a) principal: Guerra, Ana Flávia Quiles Garcia
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual de Maringá; Brasil; Programa de Pós-Graduação em Zootecnia; UEM; Maringá, PR; Centro de Ciências Agrárias
• Palavras-chave em Português: Retinol; Colecalciferol; Coloração de carne; Resistência óssea; Brasil.; Cholecalciferol; Meat color; Bone strength; Brazil.; Ciências Agrárias; Zootecnia
• Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/1654

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.