Estudo comparativo da inclusão de aditivos zootécnicos na ração de codornas japonesas em produção

Abstract

An experiment was conducted in order to evaluate the intestinal morphology, performance, egg quality and analysis of the financial feasibility of including various additives in feed during the whole production period of Japanese quails. 360 quails were distributed in a completely randomized design in a time split plot scheme (9 to 23 weeks of age and 24 to 39 weeks old) with five treatments and eight repetitions of nine birds each. The used treatments were: control, antibiotic, prebiotic, probiotic and synbiotic. The intestinal morphology was evaluated by the height and width and width/height ratio of the villus, crypt depth and villus/crypt ratio; performance, by the feed intake, egg production, egg weight average, feed conversion (kg / kg and kg / dozen), egg mass and viability; egg quality, by the Haugh unit, yolk index, percentage of egg components, shell thickness measured by the micrometer and the scanning electron microscope (SEM); financial analysis was computed by the internal rate of return, net present value and cost benefit. The inclusion of additives in the feed increased the height and width of the villi, decreased crypt depth and increased villous / crypt ratio compared to the control. The inclusion of the additives reduced the feed intake in the two periods of production of the quails in comparison with the control. Throughout the production period, consumption was lower after inclusion of antibiotic and synbiotic in the feed. Egg production, egg weight average, egg mass and feed conversion (kg / kg and kg / dozen) were improved in the quails fed with additives in the two periods of production. The supply of additives within 24 to 39 weeks of age increased the Haugh unit of the eggs compared to the control. The inclusion of additives in the feed increased the yolk and shell percentage, and improved shell and membrane thickness measured by the micrometer compared to the control in both periods of production. The shell thickness (SEM) and the shell palisade layer were improved after inclusion of antibiotic and synbiotic in the feed within 24 to 39 weeks of age. The financial analysis showed best values in the treatments that used antibiotics and synbiotic. The inclusion of antibiotics, probiotic, prebiotic and synbiotic in the feed improves performance and egg quality throughout the production phase of Japanese quails, and these improvements increase effects when the birds receive the additives in the first productive period. The inclusion of antibiotics and synbiotic is more effective than the inclusion of the other additives in reducing food intake throughout the production period and improving shell thickness during the second production period. Intestinal integrity of Japanese quails improved after the inclusion of the tested additives. The financial analysis proved to be more viable to include antibiotic or synbiotic in the feed of Japanese quails in comparison to the other studied additives.