Sorghum-soybean meal-based diets supplemented with canthaxanthin and their effects on internal egg quality of laying hens, stored in different temperatures.

Introduction. The substitution of corn to sorghum, in addition to a lower price, has greater resistance to drought, which favors its cultivation in various regions with low rainfall (Fialho; Barbosa, 1997). Although rustic, sorghum loses to be less productive and the carotenoid deficiency in maize, an effect that may be corrected by inclusion of pigments in the diets of poultry (Oliveira et al., 2008). The aim of this study was to evaluate the sorghum-soybean mealbased diets supplemented with canthaxanthin (CTX) on internal egg quality of laying hens, stored at room temperature or refrigerated.

 

Material and Methods. It was used 2400 eggs, distributed in randomized design with a 2x2 factorial arrangement [supplementation 0 or 6mg of CTX (CAROPHYLL® Red 10%, DSM Nutritional Products)/kg sorghum-soybean meal-based diet; two types of storage: room temperature (25°C) or refrigerated (4°C)], with 10 replicates of 60 eggs each one. The eggs were stored during 0, 7, 14, 21 and 28 days (d). The parameters analyzed were: egg weight (EW), yolk and albumen weight (YW and AW), yolk index (YI), Haugh unit (HU), vitelline membrane resistance (VMR), lipid oxidation (TBARS), albumen pH (pH) and mg of total carotenoids/kg of yolk (C). To determine internal quality three eggs were selected per repetition according to EW (within an interval for variance of 2.5%). To determine the C was used an iCheck™ portable photometer, for VMR was used TA.XT Texture Analyzer 123 and TBARS was measured the amount of Thiobarbituric Acid Reactive Substances. All the data were subject to analysis of variance. Tukey´s test was used for significant interaction at the 10% level. Statistical procedures were performed using SAS software.

 

Results. In the interactions study, was observed eggs from hens fed without CTX supplemented and stored at 4ºC or with CTX supplemented and stored at 25ºC had highest YW to 14d (P=0.0636) and did not differ each other. Interaction was observed between eggs stored at 4ºC from hens fed with different diets that had higher YI to 7d (P=0.0140) than eggs stored at 25ºC. Also there was interaction for C to 28d (P=0.0999), where eggs from hens fed with CTX supplemented and stored at 4ºC or 25ºC had higher carotenoids concentration/kg of yolk. Hens fed without CTX supplemented had highest AW at 14d (P=0.0217), HU at 7d (P=0.0918). Eggs stored at 4°C had highest EW from 21 to 28d (P<0.10), AW from 14 to 28d (P<0.10), HU and RVM from 7 to 28d (P<0.10) and lowest TBARS at 14d (P<0.10) and pH at 7 to 28d (P<0.10).

 

Conclusion. Eggs from hens fed sorghum- soybean meal-based diets supplemented with canthaxanthin, stored at room temperature (25ºC), improved yolk index. However, in other parameters, refrigerated temperature (4ºC) is effective to increase the shelf life of eggs.

 

References. Fialho E T and Barbosa H P. 1997. Alimentos alternativos para suínos. Lavras, MG: FAEPE. 228p; Oliveira N T E et al. 2008. Ciênc. Agrotec. 31 (5) 1525-1531.

 

Keywords: Carotenoids, refrigerated, lipid oxidation, yolk.