ABSTRACT. The use of antibiotics in feed for growth promotion has been restricted in many countries, thus it is of interest to investigate potential alternatives for enhancing growth performance in birds. An experiment was carried out to evaluate the concurrent use of prebiotic and probiotic on gut histology and some blood chemicals of broiler chickens during heat stress. A total of 144 day-old male Ross 308 broiler chicks were randomly divided into 3 treatments. The first treatment was a diluted diet including rice bran without probiotic or prebiotic. The other treatments were fed the diluted diets with a prebiotic (treatment 2) and concurrent use of that prebiotic along with a probiotic (treatment 3). Results showed that villus height was not influenced by feed additives. However, crypt depth significantly increased by feed additives in particular with combination of prebiotic and probiotic. The ratio of villus height to crypt depth significantly decreased in treatments fed prebiotic alone or prebiotic and probiotic together. This finding is indicating the fact that non-starch polysaccharides (NSPs) in high inclusion rate of rice bran caused to villus height erosion. It could be concluded that prebiotic and probiotic caused an increasing of enterocyte proliferation in the crypt of Liberkhun.

RESUMO. Um experimento foi realizado para avaliar os efeitos do extrato de Echinacea purpurea (EP) em 5 concentrações (0, 0,25, 0,5, 1 ou 2 mL L-1 de água potável) sobre o desempenho, órgãos internos e microflora intestinal de codornas japonesas (Coturnix coturnix japonica). Os resultados mostraram que o extrato diminuiu a ingestão alimentar e o ganho de peso corporal de codornas durante todo o período de estudo. A taxa de conversão alimentar de codornas alimentadas com extrato EP ao nível de 0,5 mL L-1 foi significativamente menor em relação ao grupo controle. A adição de extrato EP aos níveis de 0,25, 0,5 ou 1 mL L-1 diminuiu o rendimento de carcaça das aves (p < 0,05). O peso relativo dos órgãos internos das aves alimentadas com diferentes níveis de extrato EP não diferiu significativamente. As aves que consumiram o extrato EP nas concentrações de 1 ou 2 mL L-1 apresentaram uma menor população de bactérias aeróbicas no íleo em comparação com o grupo controle; no entanto, a população ideal de Coliform aumentou nas aves suplementadas com extrato EP (p < 0,05). Nossos resultados indicaram que o uso de extrato EP no nível de 0,5 mL L-1 de água potável melhora a taxa de conversão alimentar das codornas, no entanto, diminui o rendimento de carcaça dos animais.

ABSTRACT. An experiment was carried out to evaluate the effects of Echinacea purpurea (EP) extract at 5 levels (0, 0.25, 0.5, 1 or 2 mL L-1 of drinking water) on performance, internal organs and gut microflora of Japanese quail (Coturnix coturnix Japonica). The results showed that EP extract decreased feed intake and body weight gain of quails. The feed conversion ratio of quails fed with EP extract at the level of 0.5 ml L-1 drinking water was significantly decreased compared to the control group. Adding EP extract at the levels of 0.25, 0.5 or 1 mL L-1 drinking water decreased carcass yield of the birds (p < 0.05). The relative weight of internal organs of the birds fed different levels of EP extract was not significantly different. Birds consumed EP extract at the levels of 1 or 2 mL L-1 drinking water had lower ileal aerobic bacteria population compared to the control group; however, the ileal Coliform population increased by EP extract supplementation (p < 0.05). Results of the present study indicated that using EP extract at the level of 0.5 mL L-1 drinking water could improve feed conversion ratio of quails; however, it decreased the carcass yield of the birds.