Performance and egg quality of commercial laying hens fed with various levels of protected sodium butyrate

Two experiments were conducted to evaluate the effect of including protected sodium butyrate (PSB) in the diets of laying hens of advanced age on productive performance and egg quality. In experiment 1, a total of 320 Dekalb White 61-week-old laying hens were distributed in a randomized block design to four treatments (0, 105, 210, and 300 g/ton of PSB) with eight replicates of 10 birds. The experiment was conducted over 112 days, divided into four periods of 28 days each. Productive performance and egg quality were evaluated. In experiment 2, a total of 58 000 Dekalb White 70-week-old laying hens were assigned to diets containing either 0 or 105 g/ton of PSB with two replicates of 14 500 birds. The experiment was conducted on a commercial poultry farm. Egg production and the percentages of broken eggs and dirty eggs were evaluated. The PSB levels did not influence the productive performance of laying hens. A quadratic effect was observed for eggshell thickness, percentage of eggshell and eggshell strength, reaching maxima at 193, 136 and 198 g/ton of PSB, respectively. A quadratic effect on yolk index reached a minimum at 181 g/ton of PSB. The percentages of dirty eggs and broken eggs were lower in laying hens fed 105 g/ton of PSB. In conclusion, the addition of PSB to the diets of old laying hens improved the eggshell quality and decreased the percentage of broken and dirty eggs Keywords: egg quality, laying hens, organic acids, performance, protected sodium butyrat

Inibição e inativação in vitro de Salmonella spp. com extratos de plantas com indicativo etnográfico medicinal ou condimentar In vitro inhibition and inactivation activity of Salmonella spp. by plant extracts with spicy or medicinal ethnographic indicative

Determinou-se in vitro a intensidade de atividade de inibição bacteriana e a intensidade de atividade de inativação bacteriana, por meio de testes de diluição e suspensão em sistema de tubos múltiplos, de diferentes extratos, aquosos ou alcoólicos/hidroalcoólicos, de 86 plantas com indicativo etnográfico medicinal ou condimentar acessadas na região metropolitana de Porto Alegre, Rio Grande do Sul, frente a Salmonella spp., ou S. enteritidis ATCC nº 13076, ou S. cholera-suis ATCC nº10708, ou S. gallinarum CPVDF-SAA/RS/BR, em doses-desafio de The in vitro intensity of bacterial inhibition activity of diverse extracts (aquous, alcoholic, or hydroalcoholic) from 86 plants with medicinal and spicy ethnographic indicative, from Porto Alegre City, Rio Grande do Sul State, Brazil, were determinated in Salmonella spp. (S. enteritidis ATCC n.13076, S. cholera-suis ATCC n. 10708, or S. gallinarum CPVDF-SAA/RS/BR) in challenge dose <10(7)CFU.mL-1. Extracts of fifty plants presented some anti-Salmonella selective activity, while the other 36 extracts presented no activity. It is discussed the validity of ethnographic search instruments in the prospection of anti-bacterial protection factors in plants, as well the influence of inhibition/inactivation results in the predictivity of bacteriological diagnostic

Atividade antibacteriana in vitro de extratos de alho nirá (Allium tuberosum Rottler ex Spreng.)

Com o objetivo de demonstrar a influência da condimentação sobre a Validade Preditiva dos Resultados Negativos do diagnóstico de bactérias transmissíveis por alimentos, determinou-se, in vitro, a intensidade de atividade de inibição bacteriana (IINIB) e a intensidade de atividade de inativação bacteriana (IINAB) de três acessos de Allium tuberosum Rottler ex Spreng. - Liliaceae - alho "nirá", originários da região metropolitana de Porto Alegre, Rio Grande do Sul. O extrato etanólico à 50% destes diferentes acessos (alcoolaturas com evaporação do etanol em sistema rotavapor com reconstituição hídrica sob assepsia) foi testado, através de testes de diluição em sistema de tubos múltiplos, sobre inóculos padronizados de Staphylococcus aureus (ATCC 25.923), Enterococcus faecalis (ATCC 19.433), Salmonella enteritidis (ATCC 11.076), Escherichia coli (ATCC 11.229). Os testes revelaram atividade antibacteriana seletiva sobre os diferentes inóculos Gram-negativos, que atingiram inibição e inativação máximas e permanentes para Salmonella após 48 horas, e, para Escherichia coli, após 72 horas de exposição. As bactérias Gram-positivas, Staphylococcus e Enterococcus, apresentaram resistência total frente aos extratos etanólicos Não houve diferença significativa entre si quanto aos tempos de atuação, quanto a Salmonella e Escherichia, quanto à presença ou ausência de desinibidores bacterianos, havendo, entretanto, diferença significativa entre os acessos de alho nirá