Coproduto de goiaba desidratado na alimentação de poedeiras comerciais

Abstract

The objective was to evaluate the productive performance, egg quality, yolk colorimetry, sensory analysis, and economic efficiency of eggs from laying hens fed different levels of dehydrated guava byproduct (CGD). The experiment was conducted after approval of experimental protocol no. 5088151221 by the Ethics Committee on the Use of Animals (CEUA) of Ufra at the Poultry Experimental Shed of the Federal Rural University of the Amazon - Belém Campus. The guava byproduct was acquired through a partnership with the Cooperative of Rural Producers of the Carajás Region – COOPER, located in the municipality of Parauapebas-PA. The byproduct was sun-dried for approximately 7 days, being turned 3 times a day. 140 Bovans White laying hens were used, aged 32 weeks, and the experiment concluded at 44 weeks of age. The birds were distributed in a completely randomized experimental design into five treatments (0, 5, 10, 15, 20% inclusion of dehydrated guava by-product) with seven replicates of 4 birds in each cage. Four 21-day cycles were evaluated, totaling 84 days of evaluation. The diets were isonutritive and water was ad libitum. Productive performance evaluations were obtained from feed consumption (g/kg), feed conversion ratio (kg of feed/kg of eggs), feed conversion ratio (kg of feed/dozen eggs), average egg weight (g), egg mass produced, number of egg units per cage, egg production, and viability. For quality analysis, Haugh units, albumen index, yolk index, shell thickness, specific gravity, albumen and yolk pH, and colorimetry of raw and cooked yolks were evaluated. For sensory analysis of cooked egg yolks, a 9-point hedonic scale test was applied, evaluating: appearance, aroma, texture, flavor, and overall impression. For feed costs, economic efficiency and relative economic efficiency (%) calculations were performed. Data were analyzed using linear and quadratic regression models with the SAS program (2000) at a 5% probability level. For sensory analysis, the data were subjected to the Wilcoxon test. A linear increasing effect of the inclusion of dehydrated guava by-product was observed on feed consumption, feed conversion (kg of eggs), feed conversion (dozen), egg mass, and average egg weight. There was a quadratic effect for laying rate, but no significant effect on viability. A quadratic effect was evident for Haugh Unit. For the variables albumen index and shell percentage, there was a linear decreasing effect, respectively. Specific gravity showed a quadratic adjustment. For yolk index, albumen percentage, yolk, and shell thickness, there were no significant differences. There was a significant difference in albumen pH, indicating an increasing linear effect. There was a significant effect for L* = luminosity, b* = yellow/blue hue, and C* = chromaticity, expressing a decreasing linear effect. The analysis of h* = hue angle showed a quadratic effect. There was no significant difference for * = red/green coordinate. There were significant effects for the colorimetry of the cooked yolks; a quadratic fit was observed for the analysis of the a* (red/green) coordinate, h* = hue angle, and C* = chromaticity. There was a decreasing linear effect for b* (yellow/blue) hue, and no significant effect for luminosity. It was observed that there were no significant differences in the sensory analyses of the cooked yolks. The economic efficiency values were greater than 1.0, since the net profit exceeds the feed costs in all treatments, and the relative economic efficiency increased with the inclusion of the guava co- product. It is concluded that guava by-product is viable, and is recommended at levels between 5% and 15%. The eggs showed good acceptance by the tasters in the sensory evaluation. In addition, it reduced the cost of feed and acted as a source of pigments, accentuating the yolk color of the eggs.