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The objective was to evaluate the supplementation of fat-soluble and water-soluble vitamins on the performance and plasma concentrations of vitamins in modern hybrids pigs. A total of 144 commercial hybrid castrated male, 43.531 ± 1.099kg, were used in a randomized block design with six treatments, eight replicates and three animals per pen. The experimental treatments were different vitamin supplementation levels - 0, 25, 50, 75, 100, and 125% of the recommended by Rostagno et al. (2011) for male pigs in growth I (40 to 50kg), growth II (50 to 70kg), and finishing I (70 to 90kg) phases. For growth phases I and II, a linear effect (P<0.05) due to increase in vitamin supplementation was observed on performance. For finishing phase I and total phase, a linear effect (P<0.05) was observed with increased final average weight (FAW) and improved feed conversion ratio (FCR). For average daily weight gain (ADWG) and average daily feed intake (ADFI) a quadratic effect was observed (P<0.05). A linear (P<0.05) increase in plasmatic α-tocopherol and B12 was observed with the 125%. Thus, it is concluded that the 125% vitamin supplementation improved performance of modern hybrids pigs (40 to 90kg).

Objetivou-se avaliar a suplementação de vitaminas lipossolúveis e hidrossolúveis sobre o desempenho e as concentrações plasmáticas de vitaminas em suínos híbridos modernos. Um total de 144 híbridos machos castrados, 43,531 ± 1,099kg, foram distribuídos em delineamento de blocos ao acaso, com seis tratamentos, oito repetições e três animais por baia. Os tratamentos foram diferentes níveis de vitaminas - 0, 25, 50, 75, 100 e 125% do recomendado por Rostagno et al. (2011) para suínos machos nas fases de crescimento I (40 a 50kg), crescimento II (50 a 70kg) e terminação I (70 a 90kg). Para as fases de crescimento I e II, observou-se efeito linear (P<0,05) devido ao aumento na suplementação vitamínica sobre o desempenho. Para a fase de terminação I e a fase total, observou-se efeito linear (P<0,05) com o aumento do peso médio final (PMF) e melhoria da conversão alimentar (CA). Já para as variáveis de ganho de peso médio diário (GPMD) e consumo de ração médio diário (CRMD,) observou-se efeito quadrático (P<0,05). Houve aumento linear (P<0,05) em α-tocoferol e cobalamina plasmáticos devido à suplementação de 125%. Assim, conclui-se que a suplementação com 125% de vitaminas melhorou o desempenho de suínos híbridos modernos (40 a 90kg).

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Introduction: Leptospirosis is a zoonosis with a worldwide spread that leads to clinical manifestations ranging from asymptomatic infection to a life-threatening disease. The immune response is predominantly humoral mediated limited to the infecting serovar. Individuals living in an area endemic for leptospirosis are often exposed to an environment contaminated with leptospires and there is a paucity of information on naturally acquired immunity. In the present study, we evaluated the kinetics of agglutinating antibodies in individuals from an endemic area for leptospirosis in Salvador, Brazil comparing two different intersample collection times. Methods: Between 2017-2018, we carried out a biannual prospective cohort with 2,086 individuals living in an endemic area for leptospirosis in Salvador, Brazil. To compare agglutinating antibody kinetics using microscopic agglutination test (MAT) with different collection times, a subcohort of 72 individuals with quarterly follow-up was carried out in parallel. Results: The results revealed that using a shorter time for intersample collection led to the detection of a higher number of infections and reinfection events. Furthermore, we observed a higher rate of titer decay indicating partial and short protection. However, there was no indication of major changes in risk factors for the disease. Conclusions: We evaluated antibody kinetics among residents of an endemic area for leptospirosis comparing two sample collection times. The constant exposure to the contaminated environment increases the risk for leptospirosis infection with reinfection events being more common than expected. This indicates that the burden of leptospirosis might be underestimated by serological surveys, and further studies are necessary to better characterize the humoral response after infection.

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The objective was to determine the standardized ileal amino acid digestibility (SIAAD) in soybean meal (SBM), corn + SBM, wheat + SBM and a protein free diet (PFD) associated with phytase. A total of 672 Cobb 500 (493±10g) male chicks were distributed in a completely randomized design with twelve treatments (PFD, PFD + SBM, PFD + corn + SBM and PFD + wheat + SBM, supplemented with 0, 500 and 1000 FTU), eight replicates and seven birds per cage from 14 to 23 days. Phytase supplementation at 500 FTU increased the SIAAD of methionine in SBM (P<0.05) and threonine in corn + SBM (P<0.05). There was no significant effect (P>0.05) for the SIAAD of methionine, arginine and histidine in wheat + SBM as the phytase supplementation. However, the SIAAD of lysine, threonine, isoleucine, phenylalanine, valine, cystine, alanine, aspartic acid, glutamic acid, glycine, serine and tyrosine differed (P<0.05). In general, the SIAAD for SBM, corn + SBM and wheat + SBM are 90.32, 88.65 and 83.97% (0 FTU); 91.31, 88.81 and 88.36% (500 FTU); and 91.36, 87.09 and 87.87% (1000 FTU). In conclusion, the efficacy of phytase for improve the SIAAD vary according to the feedstuff and level of supplementation.

Objetivou-se determinar a digestibilidade ileal estandardizada dos aminoácidos (SIAAD) do farelo de soja (FS), milho + FS, trigo + FS e uma dieta livre de proteína (PFD) com fitase. Um total de 672 pintos machos (493±10g), Cobb 500, foi distribuído em um delineamento inteiramente ao acaso, com 12 tratamentos (PFD, PFD + FS, PFD + milho + FS e PFD + trigo + FS, suplementados com 0, 500 e 1000 FTU), oito repetições e sete aves por gaiola, no período de 14 a 23 dias. A suplementação de fitase em 500 FTU aumentou o SIAAD da metionina do FS (P<0,05) e da treonina do milho + FS (P<0,05). Não houve efeito significativo (P>0,05) para o SIAAD de metionina, arginina e histidina no trigo + farelo de soja à medida que os níveis de fitase aumentaram. No entanto, o SIAAD de lisina, treonina, isoleucina, fenilalanina, valina, cistina, alanina, ácido aspártico, ácido glutâmico, glicina, serina e tirosina diferiu (P<0,05). Em geral, a SIAAD do FS, milho + FS e trigo + FS foi de 90,32, 88,65 e 83,97% sem a suplementação de fitase (0 FTU); 91,31, 88,81 e 88,36% (500 FTU); e 91,36, 87,09 e 87,87% (1000 FTU). Em conclusão, a eficácia da suplementação com fitase para aumentar a SIAAD varia de acordo com o alimento e o nível de suplementação.

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This study aimed to evaluate the effects of different exogenous protease and carbohydrase in broiler diets on the nitrogen-corrected apparent metabolizable energy (AMEn) and standardized ileal amino acid digestibility (SIAAD) of soybean meals (SBM) in two Brazilian regions (Minas Gerais-MG and Rio Grande do Sul-RS). The total excreta collection of 528 14-d-old chicks was used to determine AMEn in a completely randomized design in a 2 (SBM MG and RS) x 5 (enzyme A, B, C, D and basal diet) + 1 (reference diet, RD) factorial arrangement, totaling 11 treatments, 8 repetitions, and 6 birds per experimental unit. Two experimental treatments (T1 and T6) without enzyme supplementation formulated with SBM MG and RS were used as negative control (NC). The RD without the inclusion of SBM MG and RS was used to correct the nitrogen balance. To determine the SIAAD, ileal content was collected from of broilers and the same experimental design and treatments of the previous trial were used except for the RD, which was replaced with a nitrogen-free diet (NFD) to quantify the excretion of endogenous amino acids. Soybean meal from MG showed the highest levels (p<0.05) of AME and AMEn (3,188 kcal/kg and 2,700 kcal/kg, respectively) in comparison to SBM RS (3,121 kcal/kg and 2,549 kcal/kg, respectively) and, when supplemented with the exogenous enzyme C, also improved the SIAAD (p<0.05), as compared to other enzymes.(AU)

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The objective was to evaluate the effect of dietary 25-hydroxycholecalciferol (25(OH)D3) or vitamin D3 (VitD3) and different total calcium (Ca) levels on the performance, carcass characteristics, blood, enzymatic, and bone biochemistry of broilers reared under heat stress between 1 and 42 days of age. A total of 504 male, Cobb 500, broiler chickens were distributed in a completely randomized design in a 2 × 4 factorial arrangement (VitD3 or 25(OH)D3 × four Ca levels (100, 90, 80 and 70% of the recommendations of Rostagno et al. (2011)), eight treatments, seven replicates and nine broilers per cage. Feed intake and feed conversion ratio did not (p>0.05) vary when levels of Ca were reduced and vitamin D3 sources were supplemented in the diets from 1 to 21 days for broilers chickens. 25 (OH)D3 increased weight gain results (p<0.05). From 1 to 42 d, no differences (p>0.05) were observed on performance, carcass yields and meat quality, bone deposition of Ca and P, and alkaline phosphatase concentration. Higher serum (p<0.05) concentrations of Ca and P were found in broilers fed with 25(OH)D3. The replacement of VitD3 with 25(OH)D3 and the Ca reduction of 30% in diets did not negatively affect performance, carcass characteristics, and Ca and P deposition in the tibia of broilers at 42 days of age, under heat stress.(AU)

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Objetivou-se avaliar o efeito da suplementação de cromo-metionina em dietas para frangos de corte criados em estresse por calor, no período de 22 a 43 dias de idade, nos parâmetros de qualidade da carne. Foram utilizados 336 frangos de corte, machos, da linhagem Cobb 500, com 21 dias de idade, distribuídos em delineamento em blocos inteiramente ao acaso, com quatro blocos (cada câmara climática), seis tratamentos (0; 0,10; 0,20; 0,40; 0,80 e 1,20mgkg-1 de Cr na forma de Cr-metionina), oito repetições e sete aves por unidade experimental. Aos 43 dias de idade, duas aves por unidade experimental foram selecionadas e abatidas para avaliação da qualidade da carne de peito, por meio dos parâmetros de pH15min, pH24h, luminosidade (L*), teor de vermelho (a*), teor de amarelo (b*), croma (C*), ângulo hue (Hº), capacidade de retenção de água, perda de peso por cozimento e força de cisalhamento. Houve efeito quadrático (P=0,0070) na capacidade de retenção de água da carne de peito. A suplementação de CrMet não afetou (P>0,05) os demais parâmetros de qualidade da carne. Assim, recomenda-se a suplementação de 0,59mgkg-1 de CrMet para frangos de corte para melhoria da capacidade de retenção de água do peito.(AU)

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The objective of this study was to determine the metabolizable energy, standardized ileal amino acid digestibility (SIAAD) and digestible amino acid values of wheat meal (WM), wheat gluten meal (WGM), meat bone meal (MBM) and poultry-by-product meal (PPM) in diets for broilers. In the first experiment, the total excreta collection method was used, with 180 chicks with 14 days, distributed in a completely randomized design, with 4 feeds + reference diet with 6 replicates and 6 broilers each. In the second experiment, 180 broilers from 24 to 28 days old were used, distributed in a completely randomized design, with 4 feeds + one protein free diet with 6 replicates and 6 broilers each. The AMEn values of WM, WGM, MBM and PPM were 3052, 3174, 1556 and 3200 (kcal/kg), respectively. The average SIAAD of the essential and non-essential amino acids of WM, WGM, MBM and PPM were 74.21, 97.50, 69.28 and 83.08; 76.32, 96.42, 63.93 and 77.66, respectively. The values of the main digestible limiting amino acids were 0.18, 1.42, 0.41 and 0.94 for methionine; 0.20, 1.48, 1.73 and 2.73 for lysine; 0.23, 1.67, 0.72 and 1.89 for threonine; and 0.35, 3.22, 1.38 and 2.47 for valine, respectively for the feedstuffs in study.(AU)

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This study aimed to examine the impact of levels of dietary supplementation with fat-soluble vitamins on the production performance and egg quality of laying hens. Three hundred Hy-Line White W-36 laying hens were evaluated from 28 to 44 weeks of age. The birds were allotted to one of six treatments in a randomized block design with 10 replicates with five birds each. Performance and egg quality parameters were evaluated in four 28-day periods. A corn and soybean meal-based basal diet was formulated so as to meet the nutritional requirements of the animals, with the exception of fat-soluble vitamins. The treatments consisted of dietary supplementation with 0%, 33.3%, 66.7%, 100.0%, 133.3% or 166.7% of fat-soluble vitamins (100% supplementation consisted of 7500 IU, 2000 IU, 10 IU and 1.8 mg of vitamins A, D3, E and K per kilogram of diet, respectively). Eggshell weight, shell thickness, shell strength, feed intake, egg weight, feed conversion per egg mass and feed conversion per dozen eggs showed a quadratic response (p0.05) to the treatments, whereas egg mass responded linearly. Optimal results were obtained at an average fat-soluble vitamin supplementation level of 109%, which corresponds to 8175 IU of vitamin A, 2180 IU of vitamin D3, 10.9 IU of vitamin E and 1.96 mg of vitamin K per kilogram of diet.

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This study aimed to examine the impact of levels of dietary supplementation with fat-soluble vitamins on the production performance and egg quality of laying hens. Three hundred Hy-Line White W-36 laying hens were evaluated from 28 to 44 weeks of age. The birds were allotted to one of six treatments in a randomized block design with 10 replicates with five birds each. Performance and egg quality parameters were evaluated in four 28-day periods. A corn and soybean meal-based basal diet was formulated so as to meet the nutritional requirements of the animals, with the exception of fat-soluble vitamins. The treatments consisted of dietary supplementation with 0%, 33.3%, 66.7%, 100.0%, 133.3% or 166.7% of fat-soluble vitamins (100% supplementation consisted of 7500 IU, 2000 IU, 10 IU and 1.8 mg of vitamins A, D3, E and K per kilogram of diet, respectively). Eggshell weight, shell thickness, shell strength, feed intake, egg weight, feed conversion per egg mass and feed conversion per dozen eggs showed a quadratic response (p0.05) to the treatments, whereas egg mass responded linearly. Optimal results were obtained at an average fat-soluble vitamin supplementation level of 109%, which corresponds to 8175 IU of vitamin A, 2180 IU of vitamin D3, 10.9 IU of vitamin E and 1.96 mg of vitamin K per kilogram of diet.(AU)

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1. This work investigates the apparent metabolisable energy (AME), its nitrogen-corrected form (AMEn) and amino acid (AA) digestibility coefficients of the microalgae Spirulina platensis as an ingredient in broiler chicken diets. 2. One group of birds was fed with a basal control diet (BD), and another was fed with a test diet composed of the BD with the addition of the microalgae at a proportion of 200 g/kg. AME and AMEn were assessed by total excreta collection and indigestibility analysis using acid-insoluble ash (AIA) as a marker. 3. The microalgae comprised 888.0 g/kg dry matter (DM), 18.42 MJ/kg gross energy, 514.7 g/kg crude protein, 9.9 g/kg ether extract, 10.6 g/kg crude fibre, 94.4 g/kg ash, 3.1 g/kg Ca and 11.0 g/kg P. 4. The values obtained for AME (13.48 MJ/kg DM) and AMEn (11.72 MJ/kg DM) were higher (p < 0.01) than those obtained using the AIA method (9.39-8.29 MJ/kg DM). The microalgae ileal digestibility coefficients were 0.80 ± 0.04 and 0.78 ± 0.04 for essential and non-essential AA, respectively. 5. Overall, the metabolisable energy content and digestibility of AA for S. platensis indicated that the microalgae are potentially an alternative nutrient source for broilers. The AIA method underestimated AME and AMEn in comparison to the total excreta collection method.

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