Sequence-Based Analysis of the Intestinal Microbiota of Sows and Their Offspring Fed Genetically Modified Maize Expressing a Truncated Form of Bacillus thuringiensis Cry1Ab Protein (Bt Maize)

Abstract

eThe aim was to investigate transgenerational effects of feeding genetically modified (GM) maize expressing a truncated form of Bacillus thuringiensis Cry1Ab protein (Bt maize) to sows and their offspring on maternal and offspring intestinal microbiota. Sows were assigned to either non-GM or GM maize dietary treatments during gestation and lactation. At weaning, offspring were assigned within sow treatment to non-GM or GM maize diets for 115 days, as follows: (i) non-GM maize-fed sow/non-GM maize-fed offspring (non-GM/non-GM), (ii) non-GM maize-fed sow/GM maize-fed offspring (non-GM/GM), (iii) GM maize-fed sow/non-GM maize-fed offspring (GM/non-GM), and (iv) GM maize-fed sow/GM maize-fed offspring (GM/GM). Offspring of GM maize-fed sows had higher counts of fecal total anaerobes and Enterobacteriaceae at days 70 and 100 postweaning, respectively. At day 115 postweaning, GM/non-GM offspring had lower ileal Enterobacteriaceae counts than non-GM/non-GM or GM/GM offspring and lower ileal total anaerobes than pigs on the other treatments. GM maize-fed offspring also had higher ileal total anaerobe counts than non-GM maize-fed offspring, and cecal total anaerobes were lower in non-GM/GM and GM/ non-GM offspring than in those from the non-GM/non-GM treatment. The only differences observed for major bacterial phyla using 16S rRNA gene sequencing were that fecal Proteobacteria were less abundant in GM maize-fed sows prior to farrowing and in offspring at weaning, with fecal Firmicutes more abundant in offspring. While other differences occurred, they were not observed consistently in offspring, were mostly encountered for low-abundance, low-frequency bacterial taxa, and were not associated with pathology. Therefore, their biological relevance is questionable. This confirms the lack of adverse effects of GM maize on the intestinal microbiota of pigs, even following transgenerational consumption.

In Situ Prebiotics for Weaning Piglets: In Vitro Production and Fermentation of Potato Galacto-Rhamnogalacturonan

“…observed in these fermentations appear to be a normal part of the porcine healthy gut microbiota, as they were present in high numbers in the baseline group and grew to high numbers in the control group, an observation consistent with the findings of other studies in healthy animals (56,59,63,64). In the absence of genuine illness, the actual implications of Clostridium populations are difficult to discern, and it is also uncertain whether or not the eradication of Clostridium, as seen in the UFSF treatment group, is a positive effect.…”

High-throughput Sequencing-based Analysis of the Intestinal Microbiota of Broiler Chickens Fed Genetically Modified Rice Expressing Cry1Ac/Cry1Ab Chimeric <i>Bacillus thuringiensis</i> Protein

“…Our deep 16S rRNA gene-sequencing approach detected 12 bacterial phyla in broilers, which was less than that previously detected in pigs (Buzoianu et al, 2012b(Buzoianu et al, , 2013. The main phyla identified were Firmicutes, Bacteroidetes, and Proteobacteria, and this was in agreement with previously reported data on the cecal microbiota of broilers using 16S rRNA gene sequencing (Qu et al, 2008).…”

“…Many types of Bt-crops have been commercialized worldwide, triggering concerns about their potential impact on the health of humans and livestock. A large number of feeding studies have shown that the Cry proteins expressed by Bt-crops are non-toxic to humans and mammals (Kılıç et al, 2008;Buzoianu et al, 2013;Zeljenková et al, 2014). Diets containing Bt-corn had no deleterious effects on weight gain and carcass yields of broilers (Brake et al, 2003;Taylor et al, 2003;McNaughton et al, 2007).…”

Exploring a Possible Link between the Intestinal Microbiota and Feed Efficiency in Pigs

“…The advent of high-throughput sequencing has facilitated comprehensive profiling of the resident bacteria in the digestive tracts of pigs (17,22,29,30). However, this study is one of the first to exploit this technology to examine the intestinal microbiota among pigs of varying FE.…”