Three hundred and twenty 30-week old White Leghorn cockerels were housed in individual cages and distributed in a completely randomized factorial design of 5 x 3, with five oil sources (sunflower, soybean, canola, linseed and fish/soybean) and three levels of antioxidant (30, 200 and 400 mg of vitamin E/kg). The aim of this study was to evaluate the effect of the ratio of omega6: omega3 fatty acids by the inclusion of different oil sources and of dietary supplementation with vitamin E on the reproductive performance of cockerels. The use of the fish/soybean combination determined the lowest total antioxidant status of the semen. However, the addition of vitamin E to the fish/soybean-oil-based diet resulted in a linear increase in semen volume, motility and sperm vigour in the 38th week and again in the 52nd week for motility and for sperm vigour and fertility rate in the periods from 50-53 and 41-53 weeks of age. The use of canola oil in the diet resulted in the highest fertility rate during 50-53 and 41-53 weeks of life. Animals receiving the soybean oil based diet showed the smallest fertility rate in the range from 50-53 weeks of age and concomitantly the highest level of cholesterol in the spermatozoa in the range from 47-51 weeks. An interaction between the vitamin E level and soybean oil was verified by the linear increase in motility and sperm vigour at 38 weeks of age. Later, the contrary was shown by a linear reduction in fertility in the periods from 44-46, 47-49 and 41-53 weeks of age. Cockerels that had been fed on the sunflower-oil-based diet showed the highest content of saturated fatty acids in the spermatozoa from 48-51 weeks. An interaction effect was observed between the vitamin E level and sunflower oil shown by a linear increase in the content of saturated fatty acids in the spermatozoa and a linear reduction in the C18: 1omega9, C18 :2 omega6 and PUFA (C18 : 2omega6 + C20 : 4omega6) contents in the spermatozoa at 48-51 weeks and in sperm volume at 52 weeks of age.

Intestinal mucosa structure of broiler chickens infected experimentally with Eimeria tenella and treated with essential oil of oregano

This study investigates the effect of citral on growth and on the occurrence of sublethal damage in Listeria innocua Serovar 6a (CECT 910) and Listeria monocytogenes Serovar 4b (CECT 4032) cells that were exposed to citral as a natural antimicrobial agent. Two initial inoculum concentrations were considered in this investigation: 102 and 106 cfu/mL. Citral exhibited antilisterial activity against L. innocua and L. monocytogenes, and the observed effects were dependent on the concentration of citral present in the culture medium (0, 0.150 and 0.250 μL/mL) (p ≤ 0.05). L. innocua had a shorter lag phase than L. monocytogenes, and the two species had nearly identical maximum specific growth rates. These results indicate that L. innocua could be used as surrogate for L. monocytogenes when testing the effects of this antimicrobial. Significant differences in the lag phase and growth rate were observed between the small and large inoculum concentration (p ≤ 0.05). Citral-treated L. innocua and L. monocytogenes that were recovered on selective medium (i.e., TSA-YE-SC) had a shorter lag phase and a higher maximum specific growth rate than cells that were recovered on non-selective medium (i.e., TSA-YE) (p ≤ 0.05). This result suggests that damage occurs at sublethal concentrations of citral.

No abstract

Objetivou-se avaliar os efeitos da inclusão de óleo essencial de aroeira-vermelha (Schinus terebinthifolius Raddi) como promotor de crescimento nas rações de frangos de corte sobre o desempenho e morfometria intestinal desses animais. Foram utilizados 300 pintos de um dia de vida, tipo corte, machos, linhagem Cobb. As aves foram alojadas em 20 boxes de 2m² (15 aves boxe-1), distribuídos em um delineamento inteiramente casualizado, em grupos de quatro (4) tratamentos e cinco (5) repetições, com 15 aves cada. Os grupos foram identificados como T1: dieta sem promotor de crescimento e sem óleo de aroeira-vermelha (controle negativo); T2: dieta com promotor de crescimento e sem óleo de aroeira (antimicrobiano e anticoccidiano - controle positivo); T3: dieta contendo somente antimicrobiano (bacitracina de zinco); T4: dieta com 0,4% de óleo de aroeira-vermelha. Não houve efeito significativo dos tratamentos sobre o desempenho animal (P>0,05). Contudo, quanto aos aspectos morfométricos dos intestinos verificou-se que, aos 21 dias de idade, os animais tratados com promotor de crescimento apresentaram maior relação vilo:cripta, que não diferiu dos tratados com 0,4% de óleo de aroeira-vermelha (P>0,05). As aves arraçoadas com uma dieta sem promotor de crescimento (sem antibiótico e anticoccidiano) tiveram a menor relação vilo:cripta (P<0,05). A adição de óleo de aroeira-vermelha na dieta de frangos de corte reduziu o peso relativo dos intestinos quando comparado com a dieta sem promotor de crescimento (P<0,05), não diferindo dos tratados com promotor de crescimento (P>0,05). Neste estudo, não houve diferença significativa na profundidade das criptas de Lieberkühn e na altura das vilosidades entre os tratamentos (P>0,05). Concluiu-se que a adição de 0,4% de óleo de aroeira promoveu uma melhoria na superfície absortiva intestinal das aves, quando comparado com as aves alimentadas sem promotor de crescimento.