Caracterização e digestibilidade ileal de torta de caroço de algodão pré-tratada pelo macro-basidiomiceto Fistulina hepatica CC102 em dietas para suínos

Abstract

Mushrooms may be promising biodegradable agents of gossypol present in cotton seed cake, making this residue as a future constituent in pig feed. Therefore, experiments were carried out with the objective of evaluating the biodestoxific capacity of macrofungi in cotton seed cake and the protein and amino acid digestibility of this material in swine. In the first experiment, 35 fungi belonging to the Embrapa Agroenergia edible mushroom collection were inoculated in solid medium in petri dishes using 10% cotton seed cake (ATCA), 100% cotton seed cake (TCA) and CAT medium which is a crushed cotton core medium. After this process, the fungi with the best growth in TCA were tested for the degradation of gossypol. Only 13 fungi were promising in colonization of the substrate with cotton seed cake. Of these, only, Fistulina hepatica, proved to be efficient in the degradation of gossypol. In addition, the substrates colonized by this species presented bromatological characteristics with high protein value. Tests with salty artemia and rodents did not detect anomalies or toxicide effects associated with free gossypol. The enzymes quantified in the present study proved to be efficient in the degradation of gossypol, even at low concentrations. The results obtained in this work pointed to an efficiency of P. ostreatus CC389 F. hepatica CC102 in detoxification of cotton seed cake, thus opening possibilities of integration of the production chains of biodiesel, fungiculture and the industry of animal rations. In the second experiment, surgeries were performed with implantation of a T-cannula in the final portion of the ileum in 4 pigs weighing 80 kg each. The animals went through the postoperative period and fed for 6 days with a protein-free diet (DIP) and a DIP diet containing 25% SMS from the cotton seed pie. On the sixth day of feeding, digests were withdrawn in plastic bags attached to the cannula for 24 hours. The digests were stored in freezer and lyophilized for high performance liquid chromatography (HPLC) for amino acid quantification. The apparent digestibility coefficients of the apparent protein (CDPBap), apparent ileal digestibility coefficient of the amino acids (CDAAap) and true (CDAAv) were similar to those reported in the literature (greater than 80%), showing a food promising in pork nutrition.