The production of short chain fatty acid and colonic development in weaning piglets

Weaning process widely affects the small intestinal structure and function in piglets, while the responses of large intestine to weaning stress are still obscure. The purpose of this study was to determine the developmental changes (i.e., short chain fatty acids (SCFAs) concentrations, growth parameters, crypt‐related indices and antioxidant capacity) in colon of piglet during weaning. Forty piglets were weaned at day 21 and euthanized to collect colonic tissues and digesta samples on day 0, 1, 3, 7 and 14 post‐weaning (n = 8). Piglet growth performance was improved (p < .001) on day 7 and 14 post‐weaning. The concentrations of acetate, propionate, butyrate, valerate, isobutyrate, isovalerate and total SCFAs were higher (p < .001) during the late post‐weaning period. The mRNA abundances of SCFAs transporters were greater (p < .001) on day 7 and 14. The absolute and relative weights, absolute length and perimeter of colon were greater (p < .001) on day 7 and 14. Similarly, post‐weaning increases (p < .001) in colonic crypt depth and Ki67 positive cells numbers per crypt were observed during the same period. Colonic crypt fission indices decreased (p < .01), while total crypt numbers increased (p < .001) on day 14 after weaning. Moreover, total SCFAs concentration was significantly associated with colonic growth parameters and Ki67 cells/crypt (p < .001). In addition, catalase content was decreased on day 3, 7, and 14, whereas, the concentrations of total superoxide dismutase (T‐SOD) and manganese‐containing superoxide dismutase (MnSOD) were higher (p < .05) on day 1 and 3 post‐weaning. These results showed that weaning process has a significant effect on colonic growth and development, which might be associated with the change of SCFAs concentrations in colon.     

Influence of meal frequency on postprandial variations in the production and absorption of volatile fatty acids in the digestive tract of conscious pigs

Five Large White pigs of 62.2 +/- 1.4 kg mean body weight were fitted with permanent catheters in the portal vein and carotid artery and with an electromagnetic flow probe around the portal vein to study the absorption of volatile fatty acids (VFA) by measuring the concentration of these metabolites in hourly blood samples, and by determining the portal blood flow rate for a period of 12 h after intake of a single 800-g meal (6% crude fiber) preceded by 12 or 24 h of fasting. The portal concentration of VFA mixture always highly exceeded the arterial concentration. The arterial concentrations of propionic, butyric, valeric and isovaleric acids were nearly null, accounting for an almost complete uptake of these VFA by the liver. Acetic acid also was taken up, but to a lesser extent. Total VFA absorption during 12 h was 64% higher (P less than .05) after 12 h (1,160 +/- 100 mmol/12 h) than after 24 h of preprandial fasting (740 +/- 83 mmol/12 h). It increased after the meal (P less than .05) from 82.3 +/- 7.8 mmol/h between the first and fourth hour to 107.8 +/- 7.5 mmol/h between the fifth and tenth hour when the preprandial fasting lasted 12 h; a nonsignificant increase also was found when fasting prior to the meal lasted 24 h. The composition of the VFA mixture was not modified by the length of preprandial fasting. With this type of diet there was a large predominance of acetic acid (52%) followed by propionic and butyric acids (36 and 8.5%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

短链脂肪酸在生猪产业的研究与应用

短链脂肪酸是肠道微生物发酵产物,其对机体健康的影响已被广泛研究。本文就短链脂肪酸在国内外的研究进展,综述了其对猪肠道健康和代谢健康的有益影响以及在生猪养殖中的应用,旨在为新型饲料添加剂的开发与利用提供应用和理论依据。     

肠膜蛋白粉对早期断奶仔猪生产性能及消化道发育的影响

豆粕中含有的大豆球蛋白和ｂｅｔａ -ｃｏｎｇｌｙｃｉｎｉｎ等抗原 ,可导致断奶仔猪肠粘膜细胞发生过敏反应 ,进而降低其生产性能 (谯仕彦等 ,1 995,1 996) ,因此人们试图用其他原料替代或降低日粮中的豆粕用量。研究表明 ,日粮中添加乳清粉和血浆蛋白粉能够提高断奶仔猪日采食量和日增重 (管武太 ,1 994) ,但昂贵的价格限制了其广泛的应用。最近试验表明 ,用ＤＰＳ(肠膜蛋白粉 ,其中ＤＰＳ30 、ＤＰＳ50 的粗蛋白质含量分别为 30 %、50 % )全部或部分替代乳清粉或血浆蛋白粉 ,能够在降低饲料成本的同时 ,保持甚至提高断奶仔猪的生产性能。…     

Cecal short-chain fatty acids in experimental rabbit mucoid enteropathy

Short-chain fatty acid concentrations were measured in the cecal contents of 9 healthy rabbits and 20 rabbits with experimentally induced mucoid enteropathy. In control rabbits, cecal concentration of acetate was the most abundant, followed by that of butyrate and propionate--a feature distinguishing rabbits from most other mammals. In mucoid enteropathy, cecal acetate and butyrate concentrations were lower, whereas propionate, isobutyrate, valerate, and isovalerate were increased. The results indicated that there were abnormal fermentation and cecal maldigestion in rabbits with mucoid enteropathy.     

Effects of short-chain fatty acids and lactic acids on survival of Oesophagostomum dentatum in pigs

The direct influence of intracaecal infusion of short-chain fatty acids (SCFA) and lactic acids (LA) on already established Oesophagostomum dentatum infection in cannulated pigs was investigated. We tested the hypothesis that the previously discovered anti-parasitic effect of inulin is mediated through its metabolic products SCFA and LA by infusing into cannulated pigs these compounds in amounts approximating to those produced in the pigs large intestine and caecum during the metabolism of inulin. The experiment comprised of 18 pigs--2 groups of 9 pigs in each. The normal diet used in the experiment was based on barley flour with insoluble fibre from oat husk with added soybean meal, vitamins and minerals. After 2 weeks of adaptation to the diet all the pigs were inoculated with 6,000 infective larvae of O. dentatum. Six weeks later, surgery on all pigs was performed to install cannulas into caeci. At 7 weeks post-infection (p.i.) the SCFA and LA infusion was initiated in Group 1 (experimental) pigs; at the same time pigs in Group 2 (controls) were infused with saline. At week 10 p.i., all pigs were killed and their worm burdens determined. SCFA and LA infused pigs exhibited markedly reduced fecal egg counts and worm recoveries (98 and 92% reduction, respectively, compared to saline controls). The results from this study demonstrate that SCFA and LA have a significant negative influence on established O. dentatum infection in growing pigs. The results also show that the type of dietary carbohydrates fed and its intestinal degradation can yield metabolic by products that profoundly influence helminth survival.     

Association between butyrate and short-chain fatty acid concentrations in gut contents and faeces in weaning piglets

The concentration and composition of short-chain fatty acids (SCFA) in gastrointestinal and faecal samples were studied in weaning pigs fed different amounts and composition dietary fibre (DF). In Trial 1 a total of 50 castrated piglets were fed five experimental diets with varying contents of citrus pectin (soluble fibre) and barley hulls (insoluble fibre) and gastrointestinal contents were collected at euthanasia 9 days after weaning. In Trial 2, 120 pair-wise penned piglets were allocated to the same experimental diets as in Trial 1 (24 piglets per treatment), and fresh faecal samples were collected 5 and 32 days after weaning.

There was no difference in the concentrations of SCFA caused by dietary treatments, but across treatments there was a correlation between concentration of SCFA and the proportion of butyrate. The correlation was lowest in the caecum (r² = 0.22, P = 0.0007) and highest in the distal colon (r² = 0.45, P = 0.0001). In faeces there was no relationship 5 days after weaning (r² = 0.004. P = 0.64) but a correlation of r² = 0.25 (P = 0.0001) 32 days after weaning. The results suggest that adaptive changes and differences between piglets in fermentative capacity immediately after weaning are associated not only with a higher concentration of SCFA but also a changed fermentation profile.     

Effect of feeding pelleted feed on the level of volatile fatty acids in the digestive tract of sheep]

In an experiment with wethers we investigated the effect of complete pelleted feed ration on the concentration of volatile fatty acids in the rumen and intestinal tract. The animals consumed daily 1,300 g of dry matter of a diet which contained 41.81% of meadow hay, 25.28% of barley, 15.37% of sawdust, 14.98% of molasses, 1.32% of urea and 1.24% of a vitamin-mineral supplement for a period of six months. The pelleted diet increased the total amount of volatile fatty acids, the content of propionic acid and especially the content of butyric acid. There appeared a decrease in the ratio of acetate: propionate. On the basis of the greater energy efficiency of the volatile fatty acid production the animals fed pelleted feed showed a better energy balance. A higher VFA concentration was determined also in the large intestine and the cecum, which proves the importance of fermentation porcesses in these organs.     

Inulin and isomalto-oligosaccharide alleviate constipation and improve reproductive performance by modulating motility-related hormones,short-chain fatty acids,and feces microflora in pregnant sows

Constipation in gestating and lactating sows is common and the inclusion of dietary fiber may help to alleviate this problem. We investigated the effects of inulin (INU) and isomalto-oligosaccharide (IMO), two sources of soluble dietary fiber, on gastrointestinal motility-related hormones, short-chain fatty acids (SCFA), fecal microflora, and reproductive performance in pregnant sows. On day 64 of gestation, 30 sows were randomly divided into three groups and fed as follows: a basal diet, a basal diet with 0.5% INU, and a basal diet with 0.5% IMO. We found that INU and IMO significantly modulated the levels of gastrointestinal motility-related hormones, as evidenced by an increase in substance P (P < 0.05), and a decrease in the vasoactive intestinal peptide concentrations (P < 0.05), indicating the capacity of INU and IMO to alleviate constipation. Furthermore, IMO enhanced the concentrations of acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids in the feces (P < 0.05). High-throughput sequencing showed that IMO and INU increased the fecal microflora α- and β-diversity (P < 0.05). Methanobrevibacter was more abundant (P < 0.05), whereas the richness of Turicibacter was lower in the INU and IMO groups than in the control group (P < 0.05). In addition, IMO significantly increased litter size (P < 0.05). Overall, our findings indicate that INU and IMO can relieve constipation, optimize intestinal flora, and promote reproductive performance in pregnant sows.     

The absorption of a new sustained release furazolidone formulation from the digestive tract of piglets and calves

Summary

Chyme concentrations and total recoveries of furazolidone (5 mg/kg bodyweight) were determined by a HPLC‐method, after oral administration of two different furazolidone formulations to piglets (n = 6) and pre‐ruminant calves (n = 8), provided with an ileal re‐entrant canula. Additional blood samples were taken from the calves to measure the time dependent plasma levels of furazolidone.

In the case of the normal crystalline preparation, the results indicate an almost complete absorption of the drug from the upper parts of the digestive tract. In both species, 96–99% of the dose had been absorbed by the time it reached the end of the ileum.

The mean ileal recovery of the newly developed furazolidone formulation in calves and piglets was 14% and 38%, respectively. In calves the observed maximum plasma concentrations of furazolidone after oral application of the sustained release formulation were 14 times lower than with the normal crystalline preparation.     

乳酸菌剂对断奶仔猪肠道生理指标的影响

当前,抗生素的耐药性及内源感染等问题使人们将更多注意力集中在寻找残留少、污染小的饲料添加剂,益生素作为其中之一,其生理功能及作用机理成为世界各国相关行业的研究热点.益生素又称活菌制剂,是对动物有益的微生物制剂.乳酸菌作为其中一种,可调节动物消化道微生物区系平衡、改变pH、提高消化酶活性、抑制肠道有害微生物生长,对宿主的营养、免疫应答、生物拮抗及生长等方面均产生有利影响.本试验通过在饲料中以不同方式添加乳酸菌,研究其对断奶仔猪消化道的影响,从而对乳酸菌类微生态剂的作用机理进行探讨.     

The absorption of a new sustained release furazolidone formulation from the digestive tract of piglets and calves

Chyme concentrations and total recoveries of furazolidone (5 mg/kg body-weight) were determined by a HPLC-method, after oral administration of two different furazolidone formulations to piglets (n = 6) and pre-ruminant calves (n = 8), provided with an ileal re-entrant canula. Additional blood samples were taken from the calves to measure the time dependent plasma levels of furazolidone. In the case of the normal crystalline preparation, the results indicate an almost complete absorption of the drug from the upper parts of the digestive tract. In both species, 96-99% of the dose had been absorbed by the time it reached the end of the ileum. The mean ileal recovery of the newly developed furazolidone formulation in calves and piglets was 14% and 38%, respectively. In calves the observed maximum plasma concentrations of furazolidone after oral application of the sustained release formulation were 14 times lower than with the normal crystalline preparation.     

Investigations on prophylactic effects of coarse feed structure and/or potassium diformate on the microflora in the digestive tract of weaned piglets experimentally infected with Salmonella Derby

The purpose of this study was to examine potential prophylactic effects of a coarse feed structure and/or potassium diformate (KDF as feed additive) addition to diets on the microflora of the digestive tract in reared piglets experimentally infected with Salmonella Derby. The results show that coarse grinding as well as KDF addition are able to influence positively the intestinal flora and are capable to reduce Salmonella excretion of infected piglets. Coarse grinding of main ingredients (e.g. cereals) led to an increased number of lactobacilli as well as to higher counts of Gram-positive coccoid bacteria in the colon chyme, while KDF resulted in a tendency towards lower counts of Escherichia coli within the digestive tract. Moreover, a combination of both treatments influenced the composition of the gastrointestinal flora quite positively. Furthermore, the combination of these dietetic measures resulted in a reduced Salmonella excretion rate, shorter Salmonella shedding period and a reduced translocation of Salmonella within the infected piglets. The positive effects of combining both treatments led to a significantly reduced spreading of Salmonella within the group of pigs, which might be used to diminish Salmonella prevalence in pig production.     

Effect of short-chain fatty acids on contraction of smooth muscle in the canine colon

OBJECTIVE: To determine effects of short-chain fatty acids (SCFA) on canine colonic smooth muscle. SAMPLE POPULATION: Colonic tissue obtained from 14 healthy dogs. PROCEDURE: Short-chain fatty acid (SCFA; acetate, propionate, and butyrate; 1 to 100 mmol/L)-induced contractions were compared with responses obtained with acetylmethylcholine (AMCh; 10(-4) mol/L). Roles of enteric neurons, cholinergic receptors, calcium stores in the sarcoplasmic reticulum, and extracellular calcium in the SCFA-induced responses were investigated by incubating muscle strips with tetrodotoxin (1 micromol/L), atropine (1 micromol/L), ryanodine (10 micromol/L), nifedipine (1 micromol/L), ethylene glycol-bis (beta-aminoethylether)-N,N,N',N'-tetra-acetate (EGTA; 0.1 mmol/L), or an extracellular calcium-depleted (zero extracellular calcium) solution prior to the addition of propionate or butyrate. RESULTS: Incubation with SCFA elicited isometric stress responses (0.25 to 2.15 x 10(4) N/m2) in colonic longitudinal smooth muscle. Maximal responses to butyrate and propionate (50 mmol/L) were 37 and 23%, respectively, of the maximal AMCh response. Acetate was least effective in stimulating contractile responses. Tetrodotoxin and atropine did not affect SCFA-induced contractions. Nifedipine and zero extracellular calcium solution abolished responses to butyrate and propionate, whereas EGTA attenuated (> 60%) but did not abolish those responses. Ryanodine did not affect SCFA-induced contractile responses. The SCFA did not affect colonic circular smooth muscle. CONCLUSIONS AND CLINICAL RESPONSE: The SCFA stimulate longitudinal but not circular colonic smooth muscle contractions via a direct effect on smooth muscle. The mechanism of the SCFA effect appears to involve the influx of extracellular calcium. These findings may account for some of the effects of fiber on canine colonic motility [corrected].     

The differential localization of IgA,IgM and IgG in the gut of suckled neonatal piglets

The localization of immunoglobulins IgG, IgM and IgA in tissue sections prepared from the ileum of neonatal and adult swine were compared. Eighty percent of the immunoglobulin-containing lymphoid cells in the lamina propria of conventional adult German Landrasse swine were IgA-positive with lower numbers of IgM cells and occasionally an IgG cell. Anti-μ and α-chain reagents also stained the cytoplasm of the crypt epithelial cells. By comparison to these adult control tissues, the ileum of unsuckled neonates contained no immunoglobulins although after the ingestion of colostrum, the entire cytoplasm of the villus epithelial cells stained intensely when tested for IgG with only faint staining for IgM and IgA. On the other hand, IgA and IgM were readily localized on what appears to be only the apical border of the crypt epithelial cells but in contrast to the adult, the cytoplasm of these cells was unlabelled. IgG was absent from the crypt region. We interprete these findings to indicate an important, selective role for the villus epithelium in the absorption into the neonatal circulation of colostral IgG and probably IgA and IgM, and a specialized role for the crypt epithelium in adsorbing colostral IgA and IgM; possibly by complexing with mucin-bound secretory component.