Biological response of rat fed diets with high tuber content of conventionally bred and transgenic potato resistant to necrotic strain of potato virus (PVYN). Part II. Caecal metabolism, serum enzymes and indices of non-specific defence of rats

Caecal fermentation in rats fed diets containing transgenic potato tubers

“…The results of our earlier studies indicate that genetically modified potato did not differentiate animal growth and feed utilization (Zduńczyk et al, 2004a) as well as serum enzymes and indices of non-specific defence of rats (Zduńczyk et al, 2004b), compared with non-transgenic tubers. The purpose of this study was to evaluate the potential influence of the transgenic potato on the fermentation processes in the caecum of rats.…”

Nutritional properties of tubers of conventionally bred and transgenic lines of potato resistant to necrotic strain of Potato virus Y (PVYN).

“…Tubers of transgenic line NTR2.27 (non-translated regions of PVY N genome in antisense orientation) increased the Table 3. Caecal parameters, bacterial enzyme activity and production of short chain fa�y acids (SCFA) in caecum of rats (Juśkiewicz et al, 2004, Zduńczyk et al, 2005b bulk of caecal digesta and the production of SCFA as compared to tubers of the conventional cultivar and the other transgenic clones. Taking into account some deviations, e.g., the higher content of essential amino acids in tubers of line R2.P, higher enzymatic activity in caecal digesta of rats fed a diet with tubers of somaclone Irga, and especially the increased amount of caecal digesta and higher production SCFA in the caecum of rats fed a diet with tubers of line NTR2.27, it seems reasonable to undertake a long-term feeding study to confirm the nutritional properties of tubers of transgenic lines.…”

“…The results obtained in the present study indicate that genetic modification of potato in order to improve their resistance to a necrotic strain of Potato virus Y (PVY N ) had no effect on the chemical composition (e.g., crude protein, starch, dietary fibre content and amino-acid composition of protein) and nutritional properties of tubers (diet intake and animal growth). In our original paper (Zduńczyk et al, 2005a;2005b), we described in details that greater differences between chemical composition (especially in crude protein and starch content) and biological response of rats were observed between tubers from conventional potato cultivars Irga, Ania and Maryna. The obtained results are confirmed by other researchers who worked with plants with genetically improved tolerance to herbicides and plants resistant to diseases.…”

“…All tubers used in the presented investigations were autoclaved (121°C, 1013 hPa, 15 min), dried (40°C) and ground. Our investigations, involving 3-week feeding experiment on rats, included the following determinations: the chemical composition of tubers and nutritional properties of diets with high (40%) content of tubers (Zduńczyk et al, 2005a), caecal metabolism, serum enzymes and indices of non-specific defence of rats (Zduńczyk et al, 2005b), and shortchain fa�y acids (SCFA) production in the caecum of rats (Juśkiewicz et al, 2004). Table 1 show that the crude protein, starch and fibre content in dry ma�er of potato was comparable in tubers obtained from the conventional cultivar Irga, somaclone Irga and the transgenic lines.…”