Proceedings of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Oral Communication Abstract

SAFETY ASSESSMENT OF GENETICALLY MODIFIED PLANTS IN ANIMAL NUTRITION

PIVA G.F.*, MAZZA R.*^,**, PIVA A.***, PRANDINI A.*, DELLEDONNE M.**, MAROCCO A.**

* Istituto di Scienze degli Alimenti e della Nutrizione

** Istituto di Botanica e Genetica vegetale, Facoltà di Agraria, Università Cattolica del S. Cuore, Piacenza

*** Dipartimento di Morfologia e Fisio-patologia, Facoltà di Medicina Veterinaria, Università degli Studi di Bologna

DNA horizontal transfer, DNA uptake, GM feed

Recombinant DNA technology provides new perspectives for the feed industry although is rising concerns about the safety of genetically modified plants in animal diet. This project originates as an extension of animal feeding studies on the performance of living animals, piglets and broilers, fed with conventional and genetically modified corn. A comparison between animals raised on near isogenic corn (IC) and on insect protected (Bt) corn MON 810, expressing the Cry1A(b) protein, was performed. Animals fed with Bt corn showed higher performances than animals fed with isogenic corn: the small differences in the final live weight could be due to Bt corn having lower levels of mycotoxins, as shown by preliminary analyses. The feed ingested by the animals subjected to different treatments (IC and Bt) was recovered from different parts of the gastrointestinal tract. Samples of tissues and blood were also collected. Although the horizontal transfer of DNA between species is still poorly investigated, a few publications have presented data suggesting that small fragments of DNA derived from feed could be absorbed in the intestinal tract, directly by the epithelium or mediated by the immune system, and then taken up into the blood or in specific organs. DNA fragments originating from different plant genes (zein, shrunken) and Cry1(A)b were analyzed by PCR and Southern blot: the results obtained support the literature data indicating the possible detectability of fragments of DNA as the feed materials move through the digestive system. In the case of blood, preliminary data shows the ability to occasionally detect a fragment of the high copy number endogenous plant gene, zein, but not the Bt transgene. The results are discussed in terms of technical problems concerning sampling, analytical procedures, robustness of the methods used and recovery frequency of DNA with different size.