No subchronic toxicity of multiple herbicide-resistant soybean FG72 in Sprague-Dawley rats by 90-days feeding study

Subchronic feeding study of glyphosate-tolerant maize GG2 with the gr79-epsps and gat genes in Wistar Han RCC rats

The genetically modified (GM) maize GG2 contains gr79-epsps and gat genes, conferring glyphosate tolerance. The present study aimed to investigate potential effects of maize GG2 in a 90-day subchronic feeding study on Wistar Han RCC rats. Maize grains from GG2 or non-GM maize were incorporated into diets at concentrations of 25% and 50% and administered to Wistar Han RCC rats (n = 10/sex/group) for 90 days. The basal-diet group of rats (n = 10/sex/group) were fed with common commercialized rodent diet. Compared with rats fed with the corresponding non-GM maize and the basal-diet, no biologically relevant differences were observed in rats fed with the maize GG2, according to the results of body weight/gain, feed consumption/utilization, clinical signs, mortality, ophthalmology, clinical pathology (hematology, prothrombin time, urinalysis, serum chemistry), organ weights, and gross and microscopic pathology. Under the conditions of this study, these results indicated that maize GG2 is as safe as the non-GM maize in this 90-day feeding study.

Evaluation of the impact of transgenic maize BT799 on growth, development and reproductive function of Sprague-Dawley rats in three generations

BT799 was Bacillus thuringiensis-genetic modified (GM) maize, and Sprague-Dawley (SD) rats were treated with different diet formulations containing BT799 maize grain (33% and 66%) or its non-transgenic Zhengdan 958 (ZD958, 33% and 66%). The feeding lasted for 10 (P)/14 (F1 and F2) weeks. The reproductive capacity and pathological responses were detected in each generation of rats fed with BT799 and ZD958. During the growth and development of parental rats, each group showed the same trend in body weight gain and food intake, with a few fluctuations at individual time points. No statistically significant difference was observed in reproductive data (copulation index, fertility index, and live birth rate) of rats fed with transgenic maize compared with non-transgenic maize. We observed some apparent changes in reproductive data (sperm numbers and motility) and pathological responses (organ relative weights, hematological parameters, serum chemistry parameters, and sex hormone levels) among rats fed with BT799 maize grain. However, these differences were within the laboratory's historical normal range of control SD rats and not maize grain dose-dependent. These changes were not considered to be adverse or toxic. No significant difference in macroscopic or histological adverse effects was observed between rats consuming transgenic BT799 diet and non-transgenic diet. In conclusion, the long-term intake of BT799 maize was as safe as the corresponding non-transgenic maize for three-generation SD rats.

DP-2Ø2216-6 maize does not adversely affect rats in a 90-day feeding study

Maize plants containing event DP-2Ø2216-6 (DP202216), which confers herbicide tolerance through expression of phosphinothricin acetyltransferase and enhanced grain yield potential via temporal modulation of the native ZMM28 protein, were developed for commercialization. To address current regulatory expectations, a mandatory 90-day rodent feeding study was conducted to support the safety assessment. Diets containing 50% by weight of ground maize grain from DP202216, non-transgenic control, and 3 non-transgenic reference varieties, were fully characterized, along with the grain, and diets were fed to Crl:CD®(SD) rats for at least 90 days. As anticipated, no biologically-relevant effects or toxicologically-significant differences were observed on survival, body weight/gain, food consumption/efficiency, clinical and neurobehavioral evaluations, ophthalmology, clinical pathology (hematology, coagulation, clinical chemistry, urinalysis), organ weights, or gross and microscopic pathology parameters in rats fed a diet containing up to 50% DP202216 maize grain when compared with rats fed diets containing control or reference maize grains. The results of this study support the conclusion that maize grain from plants containing event DP-2Ø2216-6 is as safe and nutritious as maize grain not containing the event and add to the significant existing database of rodent subchronic studies demonstrating the absence of hazards from consumption of edible fractions of genetically modified plants.

Untargeted Metabonomics of Genetically Modified Cows Expressing Lactoferrin Based on Serum and Milk

Metabolites of serum and milk from genetically modified (GM) cows and contrast check (CK) cows were comparatively investigated. Serum and milk were collected from genetically modified (GM) cows and contrast check (CK) cows, and then, they were analyzed using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) and gas chromatography-mass spectrometry (GC-MS). Although the level of some blood biochemical indexes for GM cows was shifted up or down, they were generally in normal physiological condition. Serum samples from lactoferrin GM cows exhibited reduced levels of amino acids and elevated levels of indoleacetate, α-keto acids, long-chain fatty acids, etc. GM milk possessed elevated levels of pentose and amino sugar metabolites, including arabitol, xylulose, glucuronate, and N-acetylgalactosamine. Interestingly, some essential nutrients, such as certain unsaturated fatty acids (e.g., eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA)), and some necessary rare sugars were significantly upregulated. Compared to the CK group, a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was conducted based on the increased or decreased metabolites identified in the serum and milk samples of the GM group. The results showed that the GM cows were in healthy condition and their milk has improved benefits for customers. The milk from genetically modified cows was found to be a promising milk source for producing recombinant human lactoferrin (rhLF) for human beings.