Intestinal epithelium of juvenile dourado Salminus brasiliensis (Cuvier, 1816) fed diet with lyophilized bovine colostrum

AbstractThe aim of this study was to evaluate the effect oflyophilized bovine colostrum (LBC) used as partialsource of dietary protein on the histological charac-teristics of the intestinal epithelium of juvenile dou-rado Salminus brasiliensis. Juveniles were fed dietscontaining 0%, 10% or 20% of LBC inclusion foreither 30 or 60 days. For the histological study, theintestine was divided into three segments, S1, S2and posterior intestine. In the S1 segment, interac-tion between treatment and period was observed inthe number of goblet cells containing sialomucin,effect of treatment in the total number of goblet cellsand effect of period in the number of goblet cellscontaining sulphomucins (P < 0.05). In the S2 seg-ment, effect of period was observed in the numberof goblet cells containing acid, neutral and totalmucins, sialomucins and the partial volume of theabsorptive mucosa (Vv) (P < 0.05). In the posteriorintestine, effect of period was observed in the thick-ness of muscle layer and number of goblet cells con-taining sialomucins and sulphomucins (P < 0.05).Considering the aspects studied, the presence of 0%,10% or 20% of LBC in the diet did not significantlyinfluence the enteric histological characteristics ofjuvenile dourado during the period of the study.Keywords: teleost, carnivorous fish, goblet cells,mucins, stereologyIntroductionThe dourado Salminus brasiliensis is largest scalyfreshwater fish of the Prata Basin (Dairiki 2009).This carnivorous, south America fish, mainlyinhabits large rivers in the basins of the Parana,Paraguay, Uruguay and San Francisco (Nakatami,Agostinho & Baumgartner 2001; Weingartner Z Glencross,Both & Allan 2007; Borghesi, Dairiki & Cyrino2009).Bovine colostrum is a rich source of animal pro-tein and constitutes an alternative to be consideredfor fish nutrition. This lacteal secretion containssignificant concentrations of lysozyme, lactoferrin,transferrin, immunoglobulins and bioactive factors,and is also considered a nutraceutical food (Pan-dey, Dar, Mondal & Nagaraja 2011). This bioac-tive molecules that are associated with colostrumcan promote the growth development of the gas-trointestinal epithelium (Blum & Hammon 2000;Pandey et al. 2011). The storage of colostrum inthe lyophilized form preserves its original featuresfor long periods of time (Castro, Capote, Alvarez A Rodrigues, Pauletti, Kindlein,Cyrino, Delgado & Machado-Neto 2009; Moretti,Nordi, Lima, Pauletti & Machado-Neto 2013;Nordi, Moretti, Lima, Pauletti, Susin & Machado-Neto 2013). Researches showed that the colos-trum can be used as source of protection, and as