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)

Qualidade interna de diferentes tipos de ovos comercializados durante o inverno e o verão / Internal quality of different types of eggs sold during the winter and summer

Objetivou-se no presente estudo avaliar a qualidade interna de ovos brancos e vermelhos, comercializados durante o inverno e o verão, no estado de São Paulo. Para tal análise, utilizaram-se ovos classificados como tamanho grande, e a avaliação da qualidade interna realizada por meio das seguintes variáveis: massa média do ovo, gravidade específica, unidade Haugh, índice de gema, coloração da gema e incidência de partículas estranhas nos ovos. O delineamento experimental foi inteiramente ao acaso, em fatorial 2 x 2 (cor da casca x épocas do ano), sendo as cores da casca: branca e vermelha, e as épocas do ano: inverno e verão. Verificou-se que, no verão, foram obtidos os menores valores de massa média do ovo, de unidade Haugh e de índice de gema, o que evidencia maior perda da qualidade do produto, provavelmente devido às elevadas temperaturas, comparativamente ao inverno. Entretanto, durante o inverno, foram observados ovos contendo discos germinativos fecundados. Conclui-se que os ovos comercializados no Vale do Ribeira, SP, apresentaram baixa qualidade e, portanto, estavam impróprios ao consumo e à industrialização.

The aim of this study was to evaluate the internal quality of white and red eggs marketed during the winter and summer in the state of São Paulo. For this analysis, eggs classified as big were used, with the evaluation of the internal quality carried out according the following variables: Average egg mass, specific gravity, Haugh unit, yolk index, yolk color and strange particles in eggs. The experimental design was completely randomized in a 2 x 2 factorial (shell color x seasons), with shell color: white and red; and seasons: winter and summer. Through the results we found that summer had the lowest values of average egg weight, Haugh unit and yolk index, showing a greater loss of product quality, probably due to the high temperatures compared to the winter. However, during the winter we observed fertilized eggs containing germ discs. We conclude that eggs sold in the Ribeira Valley - SP are of low quality and therefore unfit for consumption and industrialization.

Effect of dietary supplementation with vitamin E and stocking density on macrophage recruitment and giant cell formation in the teleost fish, Piaractus mesopotamicus.

The effect of dietary supplementation with 0, 100 and 450 mg of vitamin E (DL-alpha tocopheryl acetate)/kg of a dry diet on the kinetics of macrophage recruitment and giant cell formation in the pacu, maintained at different stocking densities (5 kg/m(3) and 20 kg/m(3)), was investigated by insertion of round glass coverslips into the subcutaneous connective tissue. After a feeding period of 18 weeks, the coverslips were implanted and later removed for examination at 2, 7 and 15 days post-implantation. Fish fed diets supplemented with 450 mg of vitamin E showed an increase (P<0.05) in the accumulation of macrophages, foreign body giant cells and Langhans type cells. The kinetics of macrophage recruitment and giant cell formation on the glass coverslips appeared to be strongly influenced by vitamin E supplementation, since fish fed a basal diet and held at high stocking densities showed low numbers of adhering cells on the coverslips, and high concentrations of plasma corticosteroids. On the other hand, fish given a diet supplemented with 450 mg of vitamin E did not show a similar difference in plasma cortisol concentrations related to stocking density. The effect of cortisol concentrations on carbohydrate metabolism, analysed by assessment of plasma glycaemia, was not clear. Blood glucose concentrations did not vary substantially with the different treatments examined. These results suggest that vitamin E may contribute to the efficiency of the fish's inflammatory response by increasing macrophage recruitment and giant cell formation in the foreign body granulomatous reaction. Vitamin E appeared to act on the stress response of pacus by preventing a stress-related immunosuppression.