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  • Author: Beata Szymczyk x
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Beata Szymczyk, Witold Szczurek, Sylwester Świątkiewicz, Krzysztof Kwiatek, Zbigniew Sieradzki, Małgorzata Mazur, Dariusz Bednarek and Michał Reichert

Abstract

Introduction

The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested.

Material and Methods

Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups.

Results

There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected.

Conclusion

MON 810 maize seems to be as safe as the conventional maize lines.

Open access

Magdalena Franczyk-Żarów, Beata Szymczyk and Renata B. Kostogrys

Abstract

The objective of this study was to produce eggs enriched with conjugated linoleic acid (CLA) and ameliorate their fatty acid profile using the appropriate combination of dietary CLA with or without vegetable oils (olive oil or rapeseed oil) and vitamin E. In Experiment 1, 25-week-old laying hens were randomly distributed into eight groups of nine. Birds were fed with a standard diet with four different levels of CLA (0.0, 0.5, 0.75, 1.0%) and vegetable oils (olive oil or rapeseed oil, both in the amount of 1.46%). In Experiment 2, hens were randomly distributed into 12 groups of nine. The same four levels of CLA with three doses of vitamin E (0, 150, 300 mg/kg of diet) were applied. In both experiments, eggs were collected twice (at 4 and 8 weeks) for fatty acid profiling using GCMS. The differences between treatment means were considered significant at P<0.05. CLA treatments significantly increased the content of CLA, saturated fatty acids (SFA), and significantly decreased the content of monounsaturated fatty acids (MUFA) in the egg yolk, whereas levels of polyunsaturated fatty acids (PUFA) were unaffected. The vegetable oils used did not prevent the negative effects of CLA effectively. Only after eight weeks of experiment 1 SFA levels were significantly lower, but MUFA levels were significantly higher in groups fed with rapeseed oil compared to groups fed with olive oil. In experiment 2, the addition of vitamin E to the hen diet did not have an essential influence on the lipid profile of egg yolks.