Dynamic changes of postprandial plasma metabolites after intake of corn-soybean meal or casein-starch diets in growing pigs

Background: Postprandial nutrients utilization and metabolism of a certain diet is a complicated process. The metabolic feature of pigs after intake of corn-soybean meal or casein-starch diets are largely unknown. Therefore,this study was conducted to investigate the dynamic postprandial changes of plasma metabolic profile using growing pigs using metabolomics.Methods: Twenty-four growing pigs with average initial body weight(BW) about 30 kg were placed in metabolic cages and then fitted with precaval vein catheters. Pigs were fed daily 4% of initial body weight. Two experimental diets were included:(i) a starch-casein based purified diet(PD) and(ii) a common corn-soybean meal diet(CD).Plasma was collected before feeding and 0.5 h, 1 h, 2 h, 4 h, 8 h after feeding.Results: In both diets, compared to prior to feeding, the concentrations of glucose, most amino acids, metabolites such as 5-aminopentanoic acid, pipecolic acid, ornithine and 5-hydroxy-L-tryptophan were significantly increased in plasma during the first hour, whereas the concentrations of plasma triglycerides, glutamate, glycine, palmitelaidic acid, 13-HODE and oleic acid were decreased in the first hour. Compared with PD group, concentration of plasma leucine and isoleucine declined at 30 min in CD group. Plasma linoleic acid, sphingosine and many dipeptides were significantly higher in pigs fed CD.Conclusion: Most significant metabolic changes occurred during the first hour after feeding and then became relatively stable after 2 h in both diets. These results show a broad scope picture of postprandial changes in plasma metabolites after intake of PD and CD and could be a reference for further nutrition intervention as well as the design of nutritional studies.

Intrauterine growth restriction alters nutrient metabolism in the intestine of porcine offspring

Background:Intrauterine growth restriction(IUGR)has negative impacts on the postnatal survival,growth and development of humans and animals,with not only on newborns but also adulthood.However,the characteristics for nutrient digestion and absorption in IUGR offspring are still largely unknown.Therefore,the normal birth weight(NBW)and IUGR growing pigs were used in this study to investigate their differences in nutrient utilization,with an expectition for further nutritional optimization of the IUGR offspring during their later life.Methods:Twelve IUGR and 12 NBW growing pigs were fitted with catheters in their portal vein to measure blood flow rate as well as nutrients and metabolites in plasma.The digestibilities of nutrients in different intestinal segments,and bacterial fermentation in the large intestine were examined to reveal the characteristics of nutrients utilization in IUGR versus NBW pigs.Results:The rate of portal venous blood flow did not differ beween IUGR and NBW pigs.Plasma concentrations of total cholesterol,triglycerides and glucose were much lower but those of urea were higher in the portal vein of IUGR pigs,compared with the NBW pigs.The ileal digestibility of dry matter,gross energy and starch were lower in IUGR pigs than in NBW pigs.IUGR increased hindgut microbial diversity and bacterial fermentation activity in the caecum.In vitro cross-fermentation of ileal digesta by caecal microbes of NBW and IUGR pigs showed that gas production was much higher for IUGR ileal digesta regardless of the source of caecal inocula.Conclusion:IUGR impairs the nutrient digestion and absorption in small intestine,reduces caecal microbial diversity and promotes bacterial fermentation in the large intestine during the growing phase.These findings aid in our understanding of nutrient metabolism in IUGR pigs and provide the basis for future nutritional interventions.

Zearalenone toxicosis on reproduction as estrogen receptor selective modulator and alleviation of zearalenone biodegradative agent in pregnant sows

Background:Zearalenone(ZEA)is a resorcylic acid lactone derivative derived from various Fusarium species that are widely found in food and feeds.The molecular structure of ZEA resembles that of the mammalian hormone 17β-oestradiol,thus zearalenone and its metabolites are known to compete with endogenous hormones for estrogen receptors binding sites and to activate transcription of oestrogen-responsive genes.However,the effect of long-term low-dose ZEA exposure on the reproductive response to Bacillus subtilis ANSB01G culture for first-parity gilts has not yet been investigated.This study was conducted to investigate the toxic effects of ZEA as an estrogen receptor selective modulator and the alleviating effects of Bacillus subtilis ANSB01G cultures as ZEA biodegraders in pregnant sows during their first parity.Results:A total of 80 first-parity gilts(Yorkshire×Landrace)were randomly assigned to four dietary treatments during gestation:CO(positive control);MO(negative control,246μg ZEA/kg diet);COA(CO+B.subtilis ANSB01G culture with 2×10^(9)CFU/kg diet);MOA(MO+B.subtilis ANSB01G culture with 2×10^(9)CFU/kg diet).There were 20 replications per treatment with one gilt per replicate.Feeding low-dose ZEA naturally contaminated diets disordered most of reproductive hormones secretion and affected estrogen receptor-αand estrogen receptor-βconcentrations in serum and specific organs and led to moderate histopathological changes of gilts,but did not cause significant detrimental effects on reproductive performance.The addition of Bacillus subtilis ANSB01G culture to the diet can effectively relieve the competence of ZEA to estrogen receptor and the disturbance of reproductive hormones secretion,and then ameliorate toxicosis of ZEA in gilts.Conclusions:Collectively,our study investigated the effects of feeding low-dose ZEA on reproduction in pregnant sows during their first parity.Feeding low-dose ZEA could modulate estrogen receptor-αand-βconcentrations in specific organs,cause disturbance of reproductive hormones and vulva swelling,and damage organ histopathology and up-regulate apoptosis in sow models.Diet with Bacillus subtilis ANSB01G alleviated negative effects of the ZEA on gilts to some extent.

Dietary supplementation of porcine bile acids improves laying performance,serum lipid metabolism and cecal microbiota in latephase laying hens

Due to the exceptional laying performance of hens,the demand on lipid metabolism and oxidation in vivo is vigorous,resulting in excessive lipid accumulation in late-phase hens,which lowers the production performance.Bile acids regulate lipid metabolism and gut microbiota in humans and animals.However,the effect of porcine bile acids on lipid metabolism and cecal microbiota in laying hens in the late phase is still unclear.A total of 360 healthy 45-week-old laying hens were chosen for a 24-week feeding trial,where 0,30,60 and 90 mg/kg porcine bile acids were added to a basal diet,respectively.The results showed that dietary supplementation of 60 mg/kg bile acids increased egg production and feed conversion(P<0.05).Also,60 and 90 mg/kg porcine bile acids reduced abdominal fat percentage and body weight(P<0.05).The levels of serum total cholesterol,triglyceride,and low-density lipoprotein cholesterol of hens decreased(P<0.05)in bile acids supplement groups.As for cecal microbiota,bile acids supplementation did not affect the alpha diversity of cecal microbiota at the genus level.Moreover,dietary supplementation of 90 mg/kg bile acids resulted in an increase in the abundance of beneficial bacteria in the cecum,such as Lactobacillus,Bifidobacterium and Turicibacter.The changes in the cecal microbiota caused by bile acids supplementation correlated with serum lipid indexes.According to KEGG pathway analysis,dietary supplementation of 60 and 90 mg/kg bile acids promoted structural transformation of the cecal microbiota to down-regulate steroid biosynthesis,up-regulate fatty acid degradation and up-regulate unsaturated fatty acid biosynthesis.Meanwhile,bile acids bioisomerization function of cecal microbiota was enhanced in 60 and 90 mg/kg bile acids treatment,and the short-chain fatty acid metabolism was also affected.In conclusion,the present study revealed dietary supplementation of porcine bile acids enriched probiotics in the gut and improved serum lipid metabolism of laying hens.These findings demonstrate that porcine bile acids can be a potential gut beneficial promoter for late-phase laying hens.