Effect of a Feed Additive Based on Organic Acids and Tangerine Wort (Citrus reticulata) as Growth Promoter for Broiler Chickens

Feed additive alternatives to antibiotics, such as organic acids, and substances rich in polyphenols, such as tangerine wort, can promote improved intestinal health in broilers by modulating the microbial population and improving nutrient utilization. In this work, a product which combines organic acids (fumaric acid 0.5%, lactic acid 5.13%, citric acid 5.44% and ascorbic acid 1.2%) and tangerine wort (Citrus reticulata) 8.36% was studied. To determine the effect and the most appropriate level of inclusion of product in the diet of broilers, an experiment was carried out with 1400-day-old male chicks, in a conventional poultry house, evaluating the performance until 42 days of age. The birds were housed in RCB design with 5 treatments and 7 replicates of 40 birds each, and the diets with the additive inclusions were evaluated: A250 (250 mg/kg), A500 (500 mg/kg), A1000 (1000 mg/kg), a negative control (NC, not supplemented), and a positive control (PC, 10 mg/kg of enramycin). The diets were formulated based on corn and soybean meal, containing added phytase and without anticoccidial; the additives replaced an inert in the basal diet. Performance characteristics, microbiota count, morphometry and jejunum morphology were evaluated. Considering the overall experimental period, the inclusion of the alternative additive based on organic acids and tangerine wort at different levels (250, 500 and 1000 mg/kg) did not result in difference from the negative control diet or the positive control with the inclusion of the antibiotic enramycin for performance traits (p>0.05), as well as for the microbiota count, morphology, jejunal morphometry and viability. Considering the period of 29-35 days alone, treatment with 500 mg/kg of alternative additive improved weight gain and feed intake of the chickens (p<0.05), but had no effect on feed conversion.(AU)

Supra-nutritional Levels of Selected B Vitamins in Animal or Vegetable Diets for Broiler Chicken

The objective of this study was to evaluate the effects of supra-nutritional level of selected B vitamins in different types of diet on broiler performance. Two experiments were conducted using male and female one-day-old chicks (n=288 each; initial body weights in experiment I and II was, respectively, 47.57 ± 0.43, and 47.98 ± 0.31) reared in batteries up to 18 days. In experiment I, the chicks were fed a corn and soybean meal-based diet and, in experiment II, a diet containing oxidized animal by-product meals and soybean oil was used. Both experiments followed a completely randomized design in a 3 × 2 factorial arrangement, consisting of the factors: i) supplementation levels of selected B vitamins (control, 3- or 6-times control of the vitamins riboflavin, pantothenic acid, niacin, folic acid and vitamin B12); ii) dietary nutritional density (low or high), totaling 6 treatments and 8 replicates of 6 birds each (3 males and 3 females). As result of this study, in Exp. I, chicks showed higher weight gain (741.1 g vs. 697.3 g) and feed intake (920.2 vs. 878.5 g) when fed low-nutritional density diet with supra-nutritional vitamin level 6-times higher than the control. However, this effect was not found in the performance of chickens fed high-nutritional density diet. Despite the poor quality of the ingredients used in Exp. II, no statistical effect was shown of the use of vitamin super-dose in rations with different dietary nutrient density. Feed conversion ratio (FCR) was significantly improved for chickens fed high-nutritional density diet (1.191 vs. 1.246 in experiment I, 1.244 vs. 1.275 in experiment II, p 0.01). We conclude that birds fed a vegetable diet formulated with low-dietary density improved body weight (BW) and feed intake (FI) when receiving supra-nutritional levels of vitamins 6-times higher than the control.(AU)

Supra-nutritional Levels of Selected B Vitamins in Animal or Vegetable Diets for Broiler Chicken

The objective of this study was to evaluate the effects of supra-nutritional level of selected B vitamins in different types of diet on broiler performance. Two experiments were conducted using male and female one-day-old chicks (n=288 each; initial body weights in experiment I and II was, respectively, 47.57 ± 0.43, and 47.98 ± 0.31) reared in batteries up to 18 days. In experiment I, the chicks were fed a corn and soybean meal-based diet and, in experiment II, a diet containing oxidized animal by-product meals and soybean oil was used. Both experiments followed a completely randomized design in a 3 × 2 factorial arrangement, consisting of the factors: i) supplementation levels of selected B vitamins (control, 3- or 6-times control of the vitamins riboflavin, pantothenic acid, niacin, folic acid and vitamin B12); ii) dietary nutritional density (low or high), totaling 6 treatments and 8 replicates of 6 birds each (3 males and 3 females). As result of this study, in Exp. I, chicks showed higher weight gain (741.1 g vs. 697.3 g) and feed intake (920.2 vs. 878.5 g) when fed low-nutritional density diet with supra-nutritional vitamin level 6-times higher than the control. However, this effect was not found in the performance of chickens fed high-nutritional density diet. Despite the poor quality of the ingredients used in Exp. II, no statistical effect was shown of the use of vitamin super-dose in rations with different dietary nutrient density. Feed conversion ratio (FCR) was significantly improved for chickens fed high-nutritional density diet (1.191 vs. 1.246 in experiment I, 1.244 vs. 1.275 in experiment II, p 0.01). We conclude that birds fed a vegetable diet formulated with low-dietary density improved body weight (BW) and feed intake (FI) when receiving supra-nutritional levels of vitamins 6-times higher than the control.

Evaluation of Dietary Glycerin Inclusion During Different Broiler Rearing Phases

The objective of this study was to evaluate the effect of the dietary addition of different levels of glycerin on the performance, litter moisture, pododermatitis incidence, and carcass and parts yield of broilers. In total, 1,610 broilers were reared in 35 pens with 46 birds each. A completely randomized experimental design, with five treatments with seven replicates was applied. The experimental treatments were: T1: control diet; T2: dietary inclusion of 5% glycerin from 1-42 days of age; T3: dietary inclusion of 10% glycerin from 1-42 days of age; T4: dietary inclusion of 5% glycerin from 7-42 days of age; T5: dietary inclusion of 10% glycerin from 7-42 days of age. The diets containing glycerin fed since the pre-starter period improved broiler weight gain and feed conversion ratio, but did not influence feed intake or livability. At the end of the experiment, the production efficiency index of the broilers fed 10% glycerin during the entire rearing period was significantly reduced compared with the other treatments. Litter moisture in the pens of broilers fed 10% glycerin during the entire rearing period was higher compared to the other treatments since day 21.Diets containing 10% glycerin, both for the entire rearing period (1-42 days) or only after the pre-starter phase (7-42 days), influenced broiler performance and incidence of severe pododermatitis, reducing the production efficiency indexes at 42 days. Glycerin may be added up to 5% in broiler´s diets with no effect on performance, litter moisture and carcass yield, indicating that this co-product of the biodiesel industry can be used as an alternative feedstuff for broilers.(AU)

Evaluation of Dietary Glycerin Inclusion During Different Broiler Rearing Phases

The objective of this study was to evaluate the effect of the dietary addition of different levels of glycerin on the performance, litter moisture, pododermatitis incidence, and carcass and parts yield of broilers. In total, 1,610 broilers were reared in 35 pens with 46 birds each. A completely randomized experimental design, with five treatments with seven replicates was applied. The experimental treatments were: T1: control diet; T2: dietary inclusion of 5% glycerin from 1-42 days of age; T3: dietary inclusion of 10% glycerin from 1-42 days of age; T4: dietary inclusion of 5% glycerin from 7-42 days of age; T5: dietary inclusion of 10% glycerin from 7-42 days of age. The diets containing glycerin fed since the pre-starter period improved broiler weight gain and feed conversion ratio, but did not influence feed intake or livability. At the end of the experiment, the production efficiency index of the broilers fed 10% glycerin during the entire rearing period was significantly reduced compared with the other treatments. Litter moisture in the pens of broilers fed 10% glycerin during the entire rearing period was higher compared to the other treatments since day 21.Diets containing 10% glycerin, both for the entire rearing period (1-42 days) or only after the pre-starter phase (7-42 days), influenced broiler performance and incidence of severe pododermatitis, reducing the production efficiency indexes at 42 days. Glycerin may be added up to 5% in broiler´s diets with no effect on performance, litter moisture and carcass yield, indicating that this co-product of the biodiesel industry can be used as an alternative feedstuff for broilers.

Metabolizable energy of different glycerine sources derived from national biodiesel production for broilers

The objective of the present study was to evaluate the quality of different glycerine sources produced in Brazil and to analyze their metabolizable energy levels and digestibility for broilers. Firstly, the composition of 10 samples of glycerine from different sources was analyzed. Secondly, glycerine from four different sources presenting contrasting compositions were selected to determine their metabolizable energy levels and digestibility in metabolism assays using 200 broilers between 21 and 29 days of age, applying the method of total excreta collection. The values of apparent metabolizable energy corrected for nitrogen balance of the four glycerine sources were 3145, 5026, 2828, and 2892 kcal/kg.

Metabolizable energy of different glycerine sources derived from national biodiesel production for broilers

The objective of the present study was to evaluate the quality of different glycerine sources produced in Brazil and to analyze their metabolizable energy levels and digestibility for broilers. Firstly, the composition of 10 samples of glycerine from different sources was analyzed. Secondly, glycerine from four different sources presenting contrasting compositions were selected to determine their metabolizable energy levels and digestibility in metabolism assays using 200 broilers between 21 and 29 days of age, applying the method of total excreta collection. The values of apparent metabolizable energy corrected for nitrogen balance of the four glycerine sources were 3145, 5026, 2828, and 2892 kcal/kg.(AU)

Effects of glycerol on the metabolism of broilers fed increasing glycerine levels

This study evaluated the metabolic response of broilers fed diets containing increasing crude glycerine levels in two bioassays. Birds were house in metabolic cages, and were distributed according to a completely randomized experimental design with five treatments of 4 replicates each (1st assay: 5 birds/ cage; 2nd assay: 1-20 days = 8 birds/ cage, and 21-42 days = 4 birds/cage). Treatments consisted of a control diet based on corn and soybean meal, and four other diets containing 2.5%, 5.0%, 7.5% and 10.0% glycerine derived from biodiesel. In experiment I, there was no effect (p>0.05) of glycerol level on liver weight or blood parameters. Serum blood glycerol levels of the birds fed 10% crude glycerine increased during the first nine days of diet intake (p 0.05). In experiment II, water intake increased (p 0.05) in the birds fed 7.5 and 10.0% crude glycerine at 4 and 8 days of age. Feed intake increased (p 0.05) on days 8 and 12 in birds fed 2.5 and 7.5% glycerine. Fecal moisture increased (p 0.05) in birds fed diets with 5.0, 7.5, and 10.0% crude glycerine on days 16 and 20. Ileal content moisture was not different (p>0.05) among treatments when birds were 42 days old. High dietary glycerine levels may induce metabolic change in broilers, such as increased blood glycerol level, water intake and fecal moisture.(AU)

Glycerine derived from biodiesel production as a feedstuff for broiler diets

The performance, carcass traits, and litter humidity of broilers fed increasing levels of glycerine derived from biodiesel production were evaluated. In this experiment, 1,575 broilers were distributed according to a completely randomized experimental design into five treatments with seven replicates of 45 birds each. Treatments consisted of a control diet and four diets containing 2.5, 5.0, 7.5, or 10% glycerine. The experimental diets contained equal nutritional levels and were based on corn, soybean meal and soybean oil. The glycerine included in the diets contained 83.4% glycerol, 1.18% sodium, and 208 ppm methanol, and a calculated energy value of 3,422 kcal AMEn/kg. Performance parameters (weight gain, feed intake, feed conversion ratio, live weight, and livability) were monitored when broilers were 7, 21, and 42 days of age. On day 43, litter humidity was determined in each pen, and 14 birds/treatment were sacrificed for the evaluation of carcass traits. During the period of 1 to 7 days, there was a positive linear effect of the treatments on weight gain, feed intake, and live weight gain. Livability linearly decreased during the period of 1 to 21 days. During the entire experimental period, no significant effects were observed on performance parameters or carcass traits, but there was a linear increase in litter humidity. Therefore, the inclusion of up to 5% glycerine in the diet did not affect broiler performance during the total rearing period.(AU)

Eficiência de uma fitase bacteriana na liberação de fósforo fítico em dietas de frangos de corte / Efficiency of a bacterial phytase to release phytate phosphorus in broiler chicken diets

Foi avaliada a eficiência de uma fitase (FT) bacteriana na liberação de fósforo fítico utilizando-se curvas de calibração para características ósseas e de desempenho em frangos de corte. O delineamento experimental foi inteiramente ao acaso, com seis tratamentos e seis repetições até 28 dias de idade. O tratamento-controle foi uma dieta à base de milho e farelo de soja deficiente em fósforo (P). Dois tratamentos corresponderam às dietas basais acrescidas de P suplementar, 0,05 por cento e 0,10 por cento, e os outros à dieta basal com 66, 99 e 131 FTU/kg de ração. A curva padrão é definida pelo efeito da adição de P suplementar consumido sobre características ósseas e de desempenho, e os resultados dos tratamentos com fitase são confrontados com a curva para cálculo de P liberado. A adição de P suplementar influenciou o ganho de peso, o peso vivo e o consumo de ração de forma quadrática, bem como miligramas de cinzas ósseas de forma linear. A curva padrão adotada foi da variável miligramas de cinzas ósseas, pois a resposta linear melhor descreve a curva. As inclusões de 66, 99 e 131 FTU/kg liberaram, respectivamente, 0,048 por cento, 0,049 por cento e 0,062 por cento de P. A fitase bacteriana é eficiente na liberação de fósforo fítico e possui viabilidade econômica.(AU)

The objective was to determine the efficiency of a bacterial phytase to release phytate phosphorus using calibration curves for performance and bone characteristics in broiler chickens. A completely randomized design with 6 treatments and 6 replicates was used in an experiment with chickens from 1 to 28 days of age. The control treatment was a diet based on corn and soybean meal deficient in phosphorus. Two treatments consisted of the basal diet supplemented with additional phosphorus (0.05 percent and 0.10 percent), and the other treatments received 66, 99 and 131 FTU/kg of feed. The standard curves represented the effect of the levels of additional P intake on performance and bone variables. Then, the responses of the phytase treatments were compared to the standard curves to calculate the P released. The increasing levels of supplemental P had a quadratic effect on weight gain, live weight and feed intake, and linear effect on mg of bone ash. The standard curve elected was mg of bone ash because linear response better represents the curve. Inclusion of 66, 99 and 131 FTU/kg released 0.048 percent, 0.049 percent and 0.062 percent. The bacterial phytase is efficient in releasing phytate, which may be of economical significance.(AU)

Efeitos da suplementação de alto nível de cobre e de biotina na dieta de suínos de 8 a 20 kg

Two trials were carried out to investigate the need for supplemental biotin in the diet of weanling pigs when high dietary copper is used as growth promoter. Wheat - soybean meal based feeds, containing marginal levels of biotin (.10 ppm) were supplemented or not with .4 ppm biotin (BIO) and 250 ppm copper (COP). The diets were fed to 168 piglets weaned at 4 weeks of age with an average weight of 7.8 kg. The trials were conducted for 5 weeks. In trial 1 there was a BIO x COP interaction (P .05) for weight gain; BIO resulted in a 10% improvement in gain in absence of COP, but not when COP was present; COP resulted in a 16% improvement in absence of BIO and no improvement when BIO was present. There was also a main effect of COP on feed efficiency (P .05), resulting in a 7% improvement. A similar tendency was observed in trial 2, but the differences were not significant (P > .05). The combination of supplemental BIO and COP did not result in further improvement in performance compared to the individual supplementation.

Dois experimentos foram conduzidos para investigar a necessidade de suplementação de biotina na dieta de leitões recém desmamados quando o cobre é utilizado como promotor de crescimento. Rações com níveis marginais de biotina (0,10 ppm), formuladas à base de trigo e farelo de soja, foram suplementadas ou não com 0,4 ppm de biotina (BIO) e 250 ppm de cobre (COB) e fornecidas a 168 leitões desmamados com 4 semanas de idade e peso médio de 7,8 kg. Os experimentos tiveram duração de 5 semanas. No experimento 1 houve uma interação BIO x COB (P 0,05) no ganho de peso dos leitões, com BIO promovendo uma melhora de 10% na ausência de COB, mas não na presença de COB; COB resultou em um aumento de 16% no ganho de peso na ausência de BIO, mas não em sua presença . Também houve uma melhora de 7% na conversão alimentar dos leitões que receberam COB (P 0,05). A mesma tendência foi observada no experimento 2, e embora a magnitude das diferenças tenha sido semelhante, não houve significância (P > 0,05). A suplementação conjunta de COB e BIO não melhorou o desempenho dos animais, em relação a sua suplementação individual.

Efeitos da suplementação independente de sódio e cloro na dieta de suínos na fase inicial

This study was conducted to assess the effects of different dietary levels of sodium (Na) and chlorine (Cl) on performance and blood electrolyte concentration of starter pigs. The treatments consisted of diets based on corn and soybean meal containing 0.12 or 0.18% Na and 0.04; 0.12 or 0.20% Cl in a factorial arrangement. Six weaning pigs were housed in each of 12 pens in a complete randomized block design with 2 replicates per treatment. The average initial weight was 7.5 kg and the trial was conducted for 4 weeks. Sodium bicarbonate and ammonium chloride were the sources of Na and Cl, respectively. Plasma determinations of Na, Cl, Ca and P were performed at the end of the trial. Sodium did not affect performance of the piglets (P >.10). The lower Cl level (.04% Cl) resulted in less weight gain and feed efficiency (P .01), than the other two higher Cl levels. The lower dietary Cl also reduced plasma Cl and P (P .01), but did not affect plasma Ca and Na. It is concluded that combinations of dietary levels of 0.12 or 0.18% Na and 0.12 or 0.20% Cl resulted in normal performance of starter pigs.

Este estudo foi realizado para avaliar os efeitos de diferentes níveis dietéticos de sódio (Na) e cloro (Cl) sobre o desempenho e concentração de eletrólitos no sangue de suínos na fase inicial. Os tratamentos consistiram de rações à base de milho e farelo de soja com 2 níveis de Na (0,12 e 0,18%) e 3 níveis de Cl (0,04; 0,12 e 0,20%) num arranjo fatorial. Foram utilizadas 12 baias, contendo 6 animais cada, num delineamento em blocos casualizados com duas repetições por tratamento. O peso médio inicial foi 7,5 kg e o experimento teve duração de quatro semanas. O bicarbonato de sódio e o cloreto de amonio foram as fontes de Na e Cl, respectivamente. As concentrações plasmáticas de cálcio, fósforo, sódio e cloro foram determinadas ao final do experimento. Não houve efeito de níveis de Na sobre o desempenho (P > 0,10) dos animais. As dietas não suplementadas com Cl (0,04% Cl) resultaram em ganho de peso e conversão alimentar inferiores (P 0,01), não havendo diferença significativa entre os outros níveis de Cl (P > 0,10). O nível mais baixo de Cl resultou em menor concentração plasmática de Cl e P (P 0,01), não afetando Ca e Na no plasma. As diferentes combinações de 0,12 ou 0,18% Na com 0,12 ou 0,20% Cl na dieta resultaram em desempenho adequado dos leitões.

Efeitos da suplementação independente de sódio e cloro na dieta de suínos na fase inicial

This study was conducted to assess the effects of different dietary levels of sodium (Na) and chlorine (Cl) on performance and blood electrolyte concentration of starter pigs. The treatments consisted of diets based on corn and soybean meal containing 0.12 or 0.18% Na and 0.04; 0.12 or 0.20% Cl in a factorial arrangement. Six weaning pigs were housed in each of 12 pens in a complete randomized block design with 2 replicates per treatment. The average initial weight was 7.5 kg and the trial was conducted for 4 weeks. Sodium bicarbonate and ammonium chloride were the sources of Na and Cl, respectively. Plasma determinations of Na, Cl, Ca and P were performed at the end of the trial. Sodium did not affect performance of the piglets (P >.10). The lower Cl level (.04% Cl) resulted in less weight gain and feed efficiency (P .01), than the other two higher Cl levels. The lower dietary Cl also reduced plasma Cl and P (P .01), but did not affect plasma Ca and Na. It is concluded that combinations of dietary levels of 0.12 or 0.18% Na and 0.12 or 0.20% Cl resulted in normal performance of starter pigs.

Este estudo foi realizado para avaliar os efeitos de diferentes níveis dietéticos de sódio (Na) e cloro (Cl) sobre o desempenho e concentração de eletrólitos no sangue de suínos na fase inicial. Os tratamentos consistiram de rações à base de milho e farelo de soja com 2 níveis de Na (0,12 e 0,18%) e 3 níveis de Cl (0,04; 0,12 e 0,20%) num arranjo fatorial. Foram utilizadas 12 baias, contendo 6 animais cada, num delineamento em blocos casualizados com duas repetições por tratamento. O peso médio inicial foi 7,5 kg e o experimento teve duração de quatro semanas. O bicarbonato de sódio e o cloreto de amonio foram as fontes de Na e Cl, respectivamente. As concentrações plasmáticas de cálcio, fósforo, sódio e cloro foram determinadas ao final do experimento. Não houve efeito de níveis de Na sobre o desempenho (P > 0,10) dos animais. As dietas não suplementadas com Cl (0,04% Cl) resultaram em ganho de peso e conversão alimentar inferiores (P 0,01), não havendo diferença significativa entre os outros níveis de Cl (P > 0,10). O nível mais baixo de Cl resultou em menor concentração plasmática de Cl e P (P 0,01), não afetando Ca e Na no plasma. As diferentes combinações de 0,12 ou 0,18% Na com 0,12 ou 0,20% Cl na dieta resultaram em desempenho adequado dos leitões.

Efeitos da suplementação de alto nível de cobre e de biotina na dieta de suínos de 8 a 20 kg

Two trials were carried out to investigate the need for supplemental biotin in the diet of weanling pigs when high dietary copper is used as growth promoter. Wheat - soybean meal based feeds, containing marginal levels of biotin (.10 ppm) were supplemented or not with .4 ppm biotin (BIO) and 250 ppm copper (COP). The diets were fed to 168 piglets weaned at 4 weeks of age with an average weight of 7.8 kg. The trials were conducted for 5 weeks. In trial 1 there was a BIO x COP interaction (P .05) for weight gain; BIO resulted in a 10% improvement in gain in absence of COP, but not when COP was present; COP resulted in a 16% improvement in absence of BIO and no improvement when BIO was present. There was also a main effect of COP on feed efficiency (P .05), resulting in a 7% improvement. A similar tendency was observed in trial 2, but the differences were not significant (P > .05). The combination of supplemental BIO and COP did not result in further improvement in performance compared to the individual supplementation.

Dois experimentos foram conduzidos para investigar a necessidade de suplementação de biotina na dieta de leitões recém desmamados quando o cobre é utilizado como promotor de crescimento. Rações com níveis marginais de biotina (0,10 ppm), formuladas à base de trigo e farelo de soja, foram suplementadas ou não com 0,4 ppm de biotina (BIO) e 250 ppm de cobre (COB) e fornecidas a 168 leitões desmamados com 4 semanas de idade e peso médio de 7,8 kg. Os experimentos tiveram duração de 5 semanas. No experimento 1 houve uma interação BIO x COB (P 0,05) no ganho de peso dos leitões, com BIO promovendo uma melhora de 10% na ausência de COB, mas não na presença de COB; COB resultou em um aumento de 16% no ganho de peso na ausência de BIO, mas não em sua presença . Também houve uma melhora de 7% na conversão alimentar dos leitões que receberam COB (P 0,05). A mesma tendência foi observada no experimento 2, e embora a magnitude das diferenças tenha sido semelhante, não houve significância (P > 0,05). A suplementação conjunta de COB e BIO não melhorou o desempenho dos animais, em relação a sua suplementação individual.

Suplementação de vitamina C associada à densidade de criação no desempenho de frangos de corte

The effect of vitamin C supplementation (75 and 150 mg/kg) was evaluated in male broiler feeding under heat stress, crowding and normal floor space conditions. The results showed that crowding conditions (10 vs. 14 birds/m²) affected negatively (P 0.05) body weight gain from 28 to 48 days of age. Feed conversion from 35 to 48 days of age was unproved (P 0.01) in birds supplemented with 75 mg/kg as compared to the control. Birds which received 150 mg of vitamin C per kg of feed showed better feed conversion than the control birds, but differences were not significant.

Avaliou-se o efeito da suplementação da vitamina C (75 e 150 mg/kg) na alimentação de frangos de corte machos sob condições de estresse de calor e superlotação. As aves foram criadas sobre "cama" de cavaco de madeira nas lotações de 10 e 14 aves/m². O delineamento experimental foi o inteiramente casualizado em esquema fatorial (3 níveis de vitamina C na ração e 2 lotações), com 5 repetições. Os resultados indicaram que o aumento da lotação de criação prejudicou (P 0,05) o ganho de peso das aves no período final da criação. A conversão alimentar dos 35 aos 48 dias de idade foi melhor (P 0,01) nas aves que receberam suplementação de 75 mg/kg em comparação com o controle. A suplementação de 150 mg/kg deu média de conversão alimentar melhor do que a média da testemunha, porem, as diferenças não foram significativas. A suplementação de vitamina C apresentou efeito benéfico no desempenho de frangos de corte. O benefício se mostrou particularmente importante na melhoria da conversão alimentar.

Suplementação de vitamina C associada à densidade de criação no desempenho de frangos de corte

The effect of vitamin C supplementation (75 and 150 mg/kg) was evaluated in male broiler feeding under heat stress, crowding and normal floor space conditions. The results showed that crowding conditions (10 vs. 14 birds/m²) affected negatively (P 0.05) body weight gain from 28 to 48 days of age. Feed conversion from 35 to 48 days of age was unproved (P 0.01) in birds supplemented with 75 mg/kg as compared to the control. Birds which received 150 mg of vitamin C per kg of feed showed better feed conversion than the control birds, but differences were not significant.

Avaliou-se o efeito da suplementação da vitamina C (75 e 150 mg/kg) na alimentação de frangos de corte machos sob condições de estresse de calor e superlotação. As aves foram criadas sobre "cama" de cavaco de madeira nas lotações de 10 e 14 aves/m². O delineamento experimental foi o inteiramente casualizado em esquema fatorial (3 níveis de vitamina C na ração e 2 lotações), com 5 repetições. Os resultados indicaram que o aumento da lotação de criação prejudicou (P 0,05) o ganho de peso das aves no período final da criação. A conversão alimentar dos 35 aos 48 dias de idade foi melhor (P 0,01) nas aves que receberam suplementação de 75 mg/kg em comparação com o controle. A suplementação de 150 mg/kg deu média de conversão alimentar melhor do que a média da testemunha, porem, as diferenças não foram significativas. A suplementação de vitamina C apresentou efeito benéfico no desempenho de frangos de corte. O benefício se mostrou particularmente importante na melhoria da conversão alimentar.