Organic acids in diets of weaned piglets: performance, digestibility and economical viability / Ácidos orgânicos em dietas para leitões desmamados: desempenho, digestibilidade e viabilidade econômica

Organic acids are used as feed additives to promote growth of weaned piglets since they prevent the occurrence of diarrhea. Thus, performance and digestibility assays were conducted and economic viability of diets was evaluated. In the performance assays, 64 hybrid piglets weaned with a mean weight of 5.87±0.31kg were divided in a randomized block design consisting of 4 treatments, 8 repetitions and 2 piglets per experimental unit (1 castrated male and 1 female). In the digestibility assay, 24 castrated male hybrid piglets with a mean weight of 8.21±0.79kg were individually assigned to 4 treatments and 6 repetitions. The treatments in the two assays were as follows: control, basal diet without addition of an acidifier; blend: inclusion of 0.5% of a mixture of organic acids; butyrate: inclusion of 0.1% of sodium butyrate; blend+butyrate: inclusion of 0.5% of a mixture of organic acids and 0.1% sodium butyrate. There was no effect (P>0.05) of the acidifiers on animal performance during the period studied. Organic acids exerted no effect (P>0.05) on the apparent digestibility coefficients of nutrients. Diets supplemented with sodium butyrate had an economic advantage for the period of 10-24 days. No episode of diarrhea was observed. This study demonstrated no effect of acidifier feed additives as growth promoters in complex diets for weaned piglets.(AU)

Ácidos orgânicos são utilizados como aditivos promotores de desempenho em leitões, pois podem prevenir a ocorrência de diarreias. Para tanto, foram conduzidos ensaios de desempenho, digestibilidade, e foi avaliada a viabilidade econômica das dietas. No desempenho, foram utilizados 64 leitões híbridos desmamados, com peso médio de 5,87±0,31kg, distribuídos em um delineamento em blocos ao acaso, com quatro tratamentos, oito repetições e dois leitões por unidade experimental (sendo um macho castrado e uma fêmea). Na digestibilidade, 24 leitões machos, castrados, híbridos, com peso médio de 8,21±0.79kg, foram alojados individualmente em quatro tratamentos e seis repetições. Em ambos os ensaios, os tratamentos foram: controle: dieta basal sem uso de acidificante; Blend: inclusão de 0,5% da mistura de ácidos orgânicos; butirato: inclusão de 0,1% de butirato de sódio; Blend+Butirato: inclusão de 0,5% da mistura de ácidos orgânicos e 0,1% butirato de sódio. Não houve efeito dos acidificantes (P>0,05) sobre o desempenho no período estudado. Não houve efeito dos ácidos orgânicos (P>0,05) sobre os coeficientes de digestibilidade aparente dos nutrientes. Dietas com suplementação de butirato de sódio apresentaram melhor vantagem econômica para o período de 10-24 dias. Não houve incidência de diarreia em nenhum período. Não ficou evidenciado o efeito dos aditivos acidificantes como promotores de crescimento em dietas complexas para leitões desmamados.(AU)

Organic acids in diets of weaned piglets: performance, digestibility and economical viability / Ácidos orgânicos em dietas para leitões desmamados: desempenho, digestibilidade e viabilidade econômica

Organic acids are used as feed additives to promote growth of weaned piglets since they prevent the occurrence of diarrhea. Thus, performance and digestibility assays were conducted and economic viability of diets was evaluated. In the performance assays, 64 hybrid piglets weaned with a mean weight of 5.87±0.31kg were divided in a randomized block design consisting of 4 treatments, 8 repetitions and 2 piglets per experimental unit (1 castrated male and 1 female). In the digestibility assay, 24 castrated male hybrid piglets with a mean weight of 8.21±0.79kg were individually assigned to 4 treatments and 6 repetitions. The treatments in the two assays were as follows: control, basal diet without addition of an acidifier; blend: inclusion of 0.5% of a mixture of organic acids; butyrate: inclusion of 0.1% of sodium butyrate; blend+butyrate: inclusion of 0.5% of a mixture of organic acids and 0.1% sodium butyrate. There was no effect (P>0.05) of the acidifiers on animal performance during the period studied. Organic acids exerted no effect (P>0.05) on the apparent digestibility coefficients of nutrients. Diets supplemented with sodium butyrate had an economic advantage for the period of 10-24 days. No episode of diarrhea was observed. This study demonstrated no effect of acidifier feed additives as growth promoters in complex diets for weaned piglets.(AU)

Ácidos orgânicos são utilizados como aditivos promotores de desempenho em leitões, pois podem prevenir a ocorrência de diarreias. Para tanto, foram conduzidos ensaios de desempenho, digestibilidade, e foi avaliada a viabilidade econômica das dietas. No desempenho, foram utilizados 64 leitões híbridos desmamados, com peso médio de 5,87±0,31kg, distribuídos em um delineamento em blocos ao acaso, com quatro tratamentos, oito repetições e dois leitões por unidade experimental (sendo um macho castrado e uma fêmea). Na digestibilidade, 24 leitões machos, castrados, híbridos, com peso médio de 8,21±0.79kg, foram alojados individualmente em quatro tratamentos e seis repetições. Em ambos os ensaios, os tratamentos foram: controle: dieta basal sem uso de acidificante; Blend: inclusão de 0,5% da mistura de ácidos orgânicos; butirato: inclusão de 0,1% de butirato de sódio; Blend+Butirato: inclusão de 0,5% da mistura de ácidos orgânicos e 0,1% butirato de sódio. Não houve efeito dos acidificantes (P>0,05) sobre o desempenho no período estudado. Não houve efeito dos ácidos orgânicos (P>0,05) sobre os coeficientes de digestibilidade aparente dos nutrientes. Dietas com suplementação de butirato de sódio apresentaram melhor vantagem econômica para o período de 10-24 dias. Não houve incidência de diarreia em nenhum período. Não ficou evidenciado o efeito dos aditivos acidificantes como promotores de crescimento em dietas complexas para leitões desmamados.(AU)

Comparison between linear and nonlinear systems of feed formulation for broilers

Two experiments were simultaneously carried out to compare feed formulation models: a linear model for minimum cost with a nonlinear model for maximum profitability for one-to 42-d-old broilers. One-d-old male or female Cobb 500 broilers (n=2368) were allocated to one of the two trials according to sex. The experiments were performed simultaneously in an experimental poultry farm. Two housing densities were used: high density (HDH), with 14 birds/m2, and low density (LDH), with 10 birds/m2. The following treatments were evaluated: linear feed formulation and LDH (LF10); nonlinear formulation and LDH (NF10); linear formulation and HDH (LF14); and nonlinear formulation and HDH (NF14). A completely randomized design with four treatments of eight replicates each was applied. Performance and cost per kg of poultry were evaluated. Both formulation systems promoted similar broiler performance. However, the high-density feed using linear formulation reduced body weight in 42-d-old males, but not when nonlinear formulation was used. The NF10 treatment yielded the worst feed conversion ratio (p 0.05) and the lowest cost/kg broiler (p 0.05) for both sexes. The results demonstrate that the nutritional program that yields the best performance is not always the most economical one.(AU)

Comparison between linear and nonlinear systems of feed formulation for broilers

Two experiments were simultaneously carried out to compare feed formulation models: a linear model for minimum cost with a nonlinear model for maximum profitability for one-to 42-d-old broilers. One-d-old male or female Cobb 500 broilers (n=2368) were allocated to one of the two trials according to sex. The experiments were performed simultaneously in an experimental poultry farm. Two housing densities were used: high density (HDH), with 14 birds/m2, and low density (LDH), with 10 birds/m2. The following treatments were evaluated: linear feed formulation and LDH (LF10); nonlinear formulation and LDH (NF10); linear formulation and HDH (LF14); and nonlinear formulation and HDH (NF14). A completely randomized design with four treatments of eight replicates each was applied. Performance and cost per kg of poultry were evaluated. Both formulation systems promoted similar broiler performance. However, the high-density feed using linear formulation reduced body weight in 42-d-old males, but not when nonlinear formulation was used. The NF10 treatment yielded the worst feed conversion ratio (p 0.05) and the lowest cost/kg broiler (p 0.05) for both sexes. The results demonstrate that the nutritional program that yields the best performance is not always the most economical one.