This study was to investigate the effect of corn naturally contaminated with aflatoxins(AF)under the regulatory level on the growth performance and health of nursery pigs,and the efficiency of yeast cell wall based fe...This study was to investigate the effect of corn naturally contaminated with aflatoxins(AF)under the regulatory level on the growth performance and health of nursery pigs,and the efficiency of yeast cell wall based feed additive(YC)mainly composed ofβ-glucans and mannan oligosaccharide(MOS)(Integral A+,Alltech,Lexington,KY)in prevention of mycotoxicosis.Pigs(60 barrows and 60 gilts at 6.02 ± 0.83kg BW)were randomly allotted to 4 treatments in a randomized complete block design based on a 2×2 factorial arrangement with 10 pens(5 barrow and 5 gilt pens)per treatment and 3 pigs per pen.Pigs were fed experimental diets for 5 wk.First factor was AF(0 or 20 mg/kg in feed)and the second factor was YC(0 or 2 g/kg in feed).Feed intake and body weight were measured weekly,and blood samples were used to measure blood cell counts,immunoglobulin G(Ig G),tumor necrosis factor-a(TNF-a),oxidative damage status,and serological evaluation related to liver health.Aflatoxin decreased(P<0.05)the number of platelet count(247.4 to 193.5×10~3/μL),and it also tended to increase the level of albumin(P=0.055,3.46 to 3.63 g/d L),albumin:globulin ratio(P=0.050,2.09 to 2.37),and Ca(P=0.080,10.79 to 10.97 mg/d L).Yeast cell wall based feed additive increased(P < 0.05)ADG(493 to 524 g/d),and ADFI(796 to 846 g/d)of pigs whereas G:F was not affected,and it also tended to increase(P=0.055)albumin level(3.46 to 3.63 g/d L).Interactions(P < 0.05)on hemoglobin,hematocrit,and platelet count indicated that YC further increased their levels when pigs were eating AF contaminated feed.Interactions(P < 0.05)on urea nitrogen and blood urea N to creatinine ratio indicated that YC further decreased their levels when feed were contaminated with AF.In conclusion,low level of 20 mg AF/kg under the regulatory level had minor effects on hematology without affecting growth performance,however the supplementation of 2 g/kg YC as a source ofβ-glucans and MOS in feed can improve feed intake and therefore the growth of pigs.展开更多
Gut health of nursery pigs immediately after weaning is tightly associated with their growth performance and economic values. Postweaning diarrhea(PWD) is one of the major concerns related to gut health of nursery pig...Gut health of nursery pigs immediately after weaning is tightly associated with their growth performance and economic values. Postweaning diarrhea(PWD) is one of the major concerns related to gut health of nursery pigs which often is caused by infections of enterotoxigenic Escherichia coli(ETEC),mainly including F4(K88)^+ and F18^+ E. coli. The main virulence factors of ETEC are adhesins(fimbriae or pili) and enterotoxins. The common types of fimbriae on ETEC from PWD pigs are F18^+ and F4^+. Typically, PWD in pigs is associated with both F18^+ and F4^+ ETEC infections whereas pre-weaning diarrhea in pigs is associated with F4+ ETEC infection. Enterotoxins including heat-labile enterotoxins(LT) and heatstable peptide toxins(ST) are associated with causing diarrhea in pigs. At least 109 to 1010 ETEC are required to induce diarrhea in nursery pigs typically lasting 1 to 5 days after ETEC infection. Antibiotics used to be the most effective way to prevent PWD, however, with the increased bacterial resistance to antibiotics, alternatives to the use of antibiotics are urgently needed to prevent PWD. Immunopropylaxis and nutritional intervention of antimicrobial minerals(such as zinc oxide and copper sulfate), organic acids, functional feedstuffs(such as blood plasma and egg yolk antibodies), direct fed microbials, phytobiotics, and bacteriophage can potentially prevent PWD associated with ETEC. Some other feed additives such as nucleotides, feed enzymes, prebiotic oligosaccharides, and clay minerals can enhance intestinal health and thus indirectly help with preventing PWD. Numerous papers show that nutritional intervention using selected feed additives can effectively prevent PWD.展开更多
This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli(ETEC)F18+on newly weaned pigs.Thirty-two pigs(16 b...This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli(ETEC)F18+on newly weaned pigs.Thirty-two pigs(16 barrows and 16 gilts,BW=6.99±0.33 kg)at 21 d of age were individually allotted in a randomized complete block design with 2×2 factorial arrangement of treatments.Pigs were selected from sows not infected previously and not vaccinated against ETEC.Pigs were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase 2.The factors were ETEC challenge(oral inoculation of saline solution or E.coli F18+at 2×109 CFU)and probiotics(none or multispecies probiotics 0.15%and 0.10%for phase 1 and 2,respectively).Body weight and feed intake were measured on d 5,9,13,19,and 25.Fecal scores were measured daily.Blood samples were taken on d 19 and 24.On d 25,all pigs were euthanized to obtain samples of digesta,intestinal tissues,and spleen.The tumor necrosis factor alpha(TNFα),malondialdehyde(MDA),peptide YY(PYY),and neuropeptide Y(NPY)were measured in serum and intestinal tissue.Data were analyzed using the MIXED procedure of SAS.The fecal score of pigs was increased(P<0.05)by ETEC challenge at the post-challenge period.The ETEC challenge decreased(P<0.05)jejunal villus height and crypt depth,tended to increase(P=0.056)jejunal TNFα,increased(P<0.05)ileal crypt depth,and decreased(P<0.05)serum NPY.The probiotics decreased(P<0.05)serum TNFα,tended to reduce(P=0.064)jejunal MDA,tended to increase(P=0.092)serum PYY,and increased(P<0.05)jejunal villus height,and especially villus height-to-crypt depth ratio in challenged pigs.Growth performance of pigs were not affected by ETEC challenge,whereas the probiotics increased(P<0.05)ADG and ADFI and tended to increase(P-0.069)G:F ratio.In conclusion,ETEC F18+challenge caused diarrhea,intestinal inflammation and morphological damages without affecting the growth performance.The multispecies probiotics enhanced growth performance by reducing intestinal inflammation,oxidative stress,morphological damages.展开更多
文摘This study was to investigate the effect of corn naturally contaminated with aflatoxins(AF)under the regulatory level on the growth performance and health of nursery pigs,and the efficiency of yeast cell wall based feed additive(YC)mainly composed ofβ-glucans and mannan oligosaccharide(MOS)(Integral A+,Alltech,Lexington,KY)in prevention of mycotoxicosis.Pigs(60 barrows and 60 gilts at 6.02 ± 0.83kg BW)were randomly allotted to 4 treatments in a randomized complete block design based on a 2×2 factorial arrangement with 10 pens(5 barrow and 5 gilt pens)per treatment and 3 pigs per pen.Pigs were fed experimental diets for 5 wk.First factor was AF(0 or 20 mg/kg in feed)and the second factor was YC(0 or 2 g/kg in feed).Feed intake and body weight were measured weekly,and blood samples were used to measure blood cell counts,immunoglobulin G(Ig G),tumor necrosis factor-a(TNF-a),oxidative damage status,and serological evaluation related to liver health.Aflatoxin decreased(P<0.05)the number of platelet count(247.4 to 193.5×10~3/μL),and it also tended to increase the level of albumin(P=0.055,3.46 to 3.63 g/d L),albumin:globulin ratio(P=0.050,2.09 to 2.37),and Ca(P=0.080,10.79 to 10.97 mg/d L).Yeast cell wall based feed additive increased(P < 0.05)ADG(493 to 524 g/d),and ADFI(796 to 846 g/d)of pigs whereas G:F was not affected,and it also tended to increase(P=0.055)albumin level(3.46 to 3.63 g/d L).Interactions(P < 0.05)on hemoglobin,hematocrit,and platelet count indicated that YC further increased their levels when pigs were eating AF contaminated feed.Interactions(P < 0.05)on urea nitrogen and blood urea N to creatinine ratio indicated that YC further decreased their levels when feed were contaminated with AF.In conclusion,low level of 20 mg AF/kg under the regulatory level had minor effects on hematology without affecting growth performance,however the supplementation of 2 g/kg YC as a source ofβ-glucans and MOS in feed can improve feed intake and therefore the growth of pigs.
文摘Gut health of nursery pigs immediately after weaning is tightly associated with their growth performance and economic values. Postweaning diarrhea(PWD) is one of the major concerns related to gut health of nursery pigs which often is caused by infections of enterotoxigenic Escherichia coli(ETEC),mainly including F4(K88)^+ and F18^+ E. coli. The main virulence factors of ETEC are adhesins(fimbriae or pili) and enterotoxins. The common types of fimbriae on ETEC from PWD pigs are F18^+ and F4^+. Typically, PWD in pigs is associated with both F18^+ and F4^+ ETEC infections whereas pre-weaning diarrhea in pigs is associated with F4+ ETEC infection. Enterotoxins including heat-labile enterotoxins(LT) and heatstable peptide toxins(ST) are associated with causing diarrhea in pigs. At least 109 to 1010 ETEC are required to induce diarrhea in nursery pigs typically lasting 1 to 5 days after ETEC infection. Antibiotics used to be the most effective way to prevent PWD, however, with the increased bacterial resistance to antibiotics, alternatives to the use of antibiotics are urgently needed to prevent PWD. Immunopropylaxis and nutritional intervention of antimicrobial minerals(such as zinc oxide and copper sulfate), organic acids, functional feedstuffs(such as blood plasma and egg yolk antibodies), direct fed microbials, phytobiotics, and bacteriophage can potentially prevent PWD associated with ETEC. Some other feed additives such as nucleotides, feed enzymes, prebiotic oligosaccharides, and clay minerals can enhance intestinal health and thus indirectly help with preventing PWD. Numerous papers show that nutritional intervention using selected feed additives can effectively prevent PWD.
文摘This study was aimed to determine the efficacy of multispecies probiotics in reducing the severity of post-weaning diarrhea caused by enterotoxigenic Escherichia coli(ETEC)F18+on newly weaned pigs.Thirty-two pigs(16 barrows and 16 gilts,BW=6.99±0.33 kg)at 21 d of age were individually allotted in a randomized complete block design with 2×2 factorial arrangement of treatments.Pigs were selected from sows not infected previously and not vaccinated against ETEC.Pigs were fed experimental diets for 25 d based on 10 d phase 1 and 15 d phase 2.The factors were ETEC challenge(oral inoculation of saline solution or E.coli F18+at 2×109 CFU)and probiotics(none or multispecies probiotics 0.15%and 0.10%for phase 1 and 2,respectively).Body weight and feed intake were measured on d 5,9,13,19,and 25.Fecal scores were measured daily.Blood samples were taken on d 19 and 24.On d 25,all pigs were euthanized to obtain samples of digesta,intestinal tissues,and spleen.The tumor necrosis factor alpha(TNFα),malondialdehyde(MDA),peptide YY(PYY),and neuropeptide Y(NPY)were measured in serum and intestinal tissue.Data were analyzed using the MIXED procedure of SAS.The fecal score of pigs was increased(P<0.05)by ETEC challenge at the post-challenge period.The ETEC challenge decreased(P<0.05)jejunal villus height and crypt depth,tended to increase(P=0.056)jejunal TNFα,increased(P<0.05)ileal crypt depth,and decreased(P<0.05)serum NPY.The probiotics decreased(P<0.05)serum TNFα,tended to reduce(P=0.064)jejunal MDA,tended to increase(P=0.092)serum PYY,and increased(P<0.05)jejunal villus height,and especially villus height-to-crypt depth ratio in challenged pigs.Growth performance of pigs were not affected by ETEC challenge,whereas the probiotics increased(P<0.05)ADG and ADFI and tended to increase(P-0.069)G:F ratio.In conclusion,ETEC F18+challenge caused diarrhea,intestinal inflammation and morphological damages without affecting the growth performance.The multispecies probiotics enhanced growth performance by reducing intestinal inflammation,oxidative stress,morphological damages.
