ABSTRACT The objective of this study was to examine the effects of replacement of an antibiotic (ANT, chlorohydroxyquinoline) in the diet of weaned piglets with a prebiotic composed of β-glucans, glucomannans, and mannan-oligosaccharides on growth performance, diarrhea occurrence (DO), hematological parameters, pH of digestive content, organ weights, intestinal epithelium morphology, and intestinal bacterial counts. A total of 120 piglets (weaned at 21 d old; 6.32±0.10 kg BW) were allocated in a randomized block design, with six pens replicates and four piglets per pen as experimental unit. Treatments consisted of diets with 0, 1,000, 2,000, or 3,000 mg kg−1 of prebiotic and a basal diet with 120 mg kg−1 ANT. No differences of treatments were observed on performance, DO, pH of digestive content, organ weights, and hematological parameters. Duodenal villus density (VD) increased linearly with the prebiotic levels. In the jejunum, the prebiotic level of 2,000 mg kg−1 resulted in a greater VD compared with the ANT. Enterobacteriaceae count in the ileum and total and lactic acid bacteria counts in the cecum responded quadratically to increasing prebiotic levels. The equations estimated the prebiotic levels of 2,125, 1,167, and 1,500 mg kg−1 to provide reduced counts of the respective bacteria (ileal enterobacteria: 6.47 log CFU g−1; total cecal bacteria: 6.70 log CFU g−1; and cecal lactic acid: 7.29 log CFU g−1). Salmonella spp. was not detected, whereas Escherichia coli and Lactobacillus spp. gene copies were unaffected by the treatments. Prebiotic levels or ANT do not enhance performance or health of weanling pigs, but the effects observed on VD and microbiota profile might be an indication of the potential benefits of these products in commercial farming conditions.

RESUMO: Objetivou-se com este estudo avaliar o efeito do uso dos óleos essenciais (OLES) de Mentha piperita e Melaleuca alternifolia em codornas de corte. Para o estudo do desempenho foi utilizado o delineamento inteiramente ao acaso, com quatrotratamentos e oito repetições, sendo sete aves por repetição. Para o estudo da lipidemia utilizou-se o delineamento inteiramente casualizado em esquema fatorial: 4x2, consistindo em quatro tratamentos e duas condições de coleta, com oito repetições, sendo uma ave por repetição. As variáveis analisadas foram: ganho de peso, consumo ração, conversão alimentar, rendimento de carcaça, colesterol, HDL, triglicerídeos, pH, capacidade de retenção de água, perda de peso por cozimento, luminosidade na carne do peito de codornas. Os dados obtidos foram analisados quanto à homocedasticidade e normalidade, as médias foram submetidas à análise de variância. O uso de OLES de M. piperita e M. alternifolia na dieta de codornas de corte pode proporcionar desempenhos zootécnicos, rendimentos de carcaça e características de qualidade da carne comparáveis ao uso de antibióticos melhoradores de desempenho. A redução no nível de colesterol HDL foi notada nas aves tratadas com Bacitracina de zinco e com os OLES de M. piperita e M. alternifolia, em 8,12; 16,52 e 3,36% respectivamente. O uso da Bacitracina de zinco, da M. piperita e da M. alternifolia associado às diferentes condições de coleta não aumentaram os valores séricos de LDL, VLDL. Os coeficientes de variação aferidos na condição “após 12 horas de jejum” apresentaram-se 86% inferiores à condição “sem jejum”.

ABSTRACT: This study evaluated the effect of essential oil (ESOL) of Mentha piperita and Melaleuca alternifolia on meat-type quails. To examine performance, a completely randomized design was used, with four treatments and eight repetitions each, using seven birds per repetition. To assess lipidemia, a completely randomized design in a 4 × 2 factorial scheme was used, with four treatments and two collection conditions using eight repetitions and one bird per repetition. Weight gain, feed intake, feed conversion, carcass yield, cholesterol, high-density lipoporteins, triglycerides, pH, and brightness of quail breast meat were assessed. The data were analyzed for homoscedasticity and normality, and the means were subjected to analysis of variance. Adding M. piperita and M. alternifolia ESOL to the diets of meat-type quails can improve performance, carcass yield, and meat quality characteristics, comparable to the use of performance-enhancing antibiotics. The use of zinc bacitracin, M. piperita, and M. alternifolia under different collection conditions did not increase the serum levels of low-density and very low-density lipoproteins. The variation coefficients measured after 12 hours of fasting were 86% lower than without fasting.

A utilização de antimicrobianos melhoradores de desempenho na criação de frangos de corte é uma prática comum na indústria avícola e, no Brasil, seu uso deve ser feito de acordo com os limites determinados pelo Ministério da Agricultura Pecuária e Abastecimento (MAPA).Objetivou-se com o presente trabalho determinar o efeito da utilização da bacitracina de zinco, dentro dos níveis recomendados pelo Ministério da Agricultura Pecuária e Abastecimento (MAPA), em dietas para frangos de corte sobre o desempenho de aves e criadas de 1 a 42 dias de idade. Utilizou-se o delineamento inteiramente casualizado, com 5 tratamentos, distribuídos em 10 repetições de 25 pintos machos de corte da linhagem Cobb 500®, totalizando 1250 aves. Os tratamentos experimentais foram constituídos de cinco níveis de inclusão de bacitracina de zinco (0, 10, 25, 40 e 55ppm). As variáveis analisadas foram consumo de ração, ganho de peso, conversão alimentar e avaliação econômica das dietas. Para o período total de criação, avaliou-se também a viabilidade dos frangos de corte. A bacitracina de zinco foi eficiente como beneficiador do desempenho de frangos de corte criados no período de 1 a 21, 1 a 35 e 1 a 42 dias. Para o período de 1 a 21 dias, o uso de 55 e 29,3ppm de bacitracina de zinco resultou em menor consumo de ração e maior ganho de peso, respectivamente. No geral, a melhor conversão alimentar foi obtida quando se adicionou 55ppm de bacitracina de zinco na ração de frangos de corte.

The use of growth promoters in the broilers production is a common practice in the poultry industry and its use must be made accordance with limits in Brazil set by the Ministry of Agriculture, Livestock and Supply (MAPA).The main objective of this study was to verify the effect of the use of zinc bacitracin, within the levels recommended by the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA), in broiler diets for the performance of birds from 1 to 42 days old. We used a randomized design with five treatments in 10 replications of 25 male chicks from Cobb cut 500®, totaling 1250 birds. The treatments consisted of five inclusion levels of zinc bacitracin (0, 10, 25, 40 and 55ppm). The variables studied were feed intake, weight gain, feed conversion and economic evaluation of feed. For the breeding period as a whole, this study also evaluated the viability of broilers. Zinc bacitracin was effective as growth promoter of broilers reared during 1 to 21, 1 to 35 and 1 to 42 days. For the period 1-21 days, using 55 and 29.3ppm of zinc bacitracin resulted in a lower feed intake and increased weight gain, respectively. In general, the best feed conversion was obtained when 55ppm of zinc bacitracin was added to the feed of broilers.

The objective of this experiment was to evaluate the use of probiotic based upon Bacillus subtilis C-3102 (BS) in broiler diets containing or not conventional additive growth-promoter (AGP). A total of 1,824 one-day-old chicks of the Cobb-500 strain were used and distributed into 48 plots (1.50 × 2.00 m). A completely randomized design with four treatments and 12 repetitions was adopted. The treatments evaluated were: 1- Negative Control - AGP-free diet (NC); 2 - Positive Control, with AGP halquinol 30 mg/kg diet (PC); 3 - NC + BS (3x10(5) cfu/g diet); and 4 - PC + BS (3x10(5) cfu/g diet). The diets were on corn, soybean meal and meat and bone meal basis, formulated according to the nutrient allowances of the Strain Cobb Guide, following a feed program with three diets (starter, grower and finisher). At 21 and 42 days of age, feed intake, weight gain and feed conversion were evaluated, and carcass yield characteristics were determined at 42 days of age. Throughout the trial period (starter and total phases), better feed conversion was found for broilers fed diet with both additives (AGP and BS) combined. At the end of the experiment (1 to 42 days), the highest weight gain also occurred in broilers fed diets with a combination of the two additives. In present study, the use of BS or AGP alone in diets did not affect the performance of broilers. The carcass yield was not influenced by the use of the additives and beneficial effects of supplementation of BS and AGP combined in the diet on broiler performance were observed.

O experimento foi conduzido com o objetivo de avaliar níveis de suplementação de vitamina D proveniente de duas fontes (D3 e 25-OHD3) em rações para frangos de corte criados em gaiolas. Foram utilizados 1.500 pintos machos de 1 dia, linhagem Cobb-700, alojados em gaiolas metálicas (100) com dispositivos e manejo adaptados para criação das aves. Em cada fase do desenvolvimento (inicial, de 1 a 21 dias; de crescimento, 22 a 38 dias; e final, de 39 a 45 dias), avaliaram-se quatro níveis (programas) de suplementação de vitamina D (20/16/10; 37,5/30/18,8; 87,5/70/43,8 e 137,5/110/68,8 mg/kg ração), oriunda de duas fontes. Os dois tratamentos adicionais foram constituídos da combinação das duas fontes (D3 + 25-OHD3), em diferentes proporções (50+37,7/40+30/25+18,8 e 50+70/40+56/25+35 mg/kg de ração para as fases inicial, crescimento e final, respectivamente). O delineamento experimental foi inteiramente casualizado, em esquema fatorial 2 × 4 + 2 (fontes × níveis + adicionais) e 10 repetições por tratamento As rações foram à base de milho e farelo de soja, com suplementação de fitase (500 ftu/kg), segundo recomendações das tabelas brasileiras de exigências nutricionais de animais não-ruminantes. Foram avaliados o desempenho, o rendimento de carcaça e a morfologia intestinal das aves. A suplementação de vitamina D na fase inicial melhorou o ganho de peso e a conversão alimentar das aves. Maior ganho de peso e consumo de ração aos 45 dias foi observado nas aves dos tratamentos adicionais (associações). O rendimento de carcaça aumentou com o uso de 25-OHD3. Em comparação à suplementação isolada das fontes de vitamina D, os tratamentos adicionais promoveram maiores benefícios para a maioria das características avaliadas. A adição de 25-OHD3 em rações contendo vitamina D3 melhora as características de desempenho dos frangos de corte.

The experiment was conducted aiming at evaluating the levels of supplementation of vitamin D from two sources (vitamin D3 and 25-OHD3) on diets for broiler chickens raised in cages. It was used 1,500 line Cobb-700 male chicks at one day of age, housed in metal cages (100), with appliances and management fitted for bird raising. In each growing phase (starter, from 1 to 21 days; growing, from 22 to 38 days, and finishing, from 39 to 45 days), it was evaluated four levels (programs) of vitamin D supplementation (20/16/10; 37.5/30/18.8; 87.5/70/43.8 and 137.5/110/68.8 mg/kg ration) from two sources. The two additional treatments consisted of combination of the two sources (D3 + 25-OHD3) at different proportions (50+37.7/40+30/25+18.8 and 50+70/40+56/25+35 mg/kg ration for starter, growing and finishing phases, respectively). It was used a complete random experimental design, in a 2 × 4 + 2 (sources × levels + aditionals) and 10 replicates per treatment. The diets were based on corn and soybean meal, with supplementation of phytase (500 ftu/kg), following the recommendations of the national tables of nutritional requirements of non-ruminant animals. The performance and carcass characteristics as well as the intestinal morphology of the birds were evaluated. Vitamin-D supplementation at the starter phase improved weight gain and feed conversion of the birds. Greater weight gain and feed intake at 45 days of age were observed for the group of birds of the additional treatment associations. Carcass yield increased with the use of 25-OHD3. When compared to the single supplementation of vitamin D sources, the additional treatments promoted more benefits for most of the evaluated characteristics. The addition of 25-OHD3 in rations containing vitamin D3 improves performance characteristics of broilers.