Effects of short-term feeding of Bt MON810 maize on growth performance, organ morphology and function in pigs.

摘要

Male weanling pigs (n 32) with a mean initial body weight of 7.5[NON-BREAKING SPACE]kg and a mean weaning age of 28[NON-BREAKING SPACE]d were used in a 31[NON-BREAKING SPACE]d study to investigate the effects of feeding GM (Bt MON810) maize on growth performance, intestinal histology and organ weight and function. At weaning, the pigs were fed a non-GM starter diet during a 6[NON-BREAKING SPACE]d acclimatisation period. The pigs were then blocked by weight and litter ancestry and assigned to diets containing 38.9[NON-BREAKING SPACE]% GM (Bt MON810) or non-GM isogenic parent line maize for 31 d. Body weight and feed disappearance were recorded on a weekly basis (n 16/treatment), and the pigs (n 10/treatment) were killed on day 31 for the collection of organ, tissue and blood samples. GM maize-fed pigs consumed more feed than the control pigs during the 31[NON-BREAKING SPACE]d study (P[NON-BREAKING SPACE]<[NON-BREAKING SPACE]0.05) and were less efficient at converting feed to gain during days 14-30 (P[NON-BREAKING SPACE]<[NON-BREAKING SPACE]0.01). The kidneys of the pigs fed GM maize tended to be heavier than those of control pigs (P[NON-BREAKING SPACE]=[NON-BREAKING SPACE]0.06); however, no histopathological changes or alterations in blood biochemistry were evident. Small intestinal morphology was not different between treatments. However, duodenal villi of GM maize-fed pigs tended to have fewer goblet cells/mum of villus compared with control pigs (P[NON-BREAKING SPACE]=[NON-BREAKING SPACE]0.10). In conclusion, short-term feeding of Bt MON810 maize to weaned pigs resulted in increased feed consumption, less efficient conversion of feed to gain and a decrease in goblet cells/mum of duodenal villus. There was also a tendency for an increase in kidney weight, but this was not associated with changes in histopathology or blood biochemistry. The biological significance of these findings is currently being clarified in long-term exposure studies in pigs.