Potential of blended organic acids to improve performance and health of broilers infected with necrotic enteritis

Organic acids(OA)and their blends have been shown to positively affect performance and health of broilers.However,the data in the literature are not consistent.This study examined the potential of blended short-chain fatty acids(SCFA)with medium-chain fatty acids(MCFA)as alternatives to antibiotic growth promoters(AGP)on performance,health and welfare of broilers infected with necrotic enteritis(NE).The additives used were:A)a blend of SCFA,MCFA,and a phenolic compound(SMP);B)a blend of free and buffered SCFA with MCFA(SMF);C)a blend of free and buffered SCFA with a high concentration of MCFA(SHM).A total of 1,404 Ross 308 one-day-old male parental chicks were randomly distributed into 78-floor pens with 13 replicates of 18 birds each.Six treatments were the following:T1,unchal-lenged control(UCC);T2,challenged control(CHC);T3,challenged group plus zinc bacitracin(BAC);T4,challenged group plus additive SMP;T5,challenged group plus additive SMF;T6,challenged group plus additive SHM.Challenged birds were gavaged with Eimeria spp.on d 9 and Clostridium perfringens EHE-NE18 on d 14.Post NE challenge and cumulatively,BWG,FCR,and nutrient digestibility of birds were compromised(P<0.05)by NE challenge indicating a successful induction of sub-clinical NE.Additive SHM had higher BWG compared to CHC and BAC groups(P=0.001;d 10 to 24)but not different from SMP and SMF groups(P>0.05).All the 3 additive groups had lower FCR compared to CHC(P=0.001;d 0 to 35),and exhibited similar jejunal lesions(d 16)compared to BAC and apparent ileal protein di-gestibility(d 21)compared to UCC and BAC groups(P>0.05).Birds in additive SHM group had a higher concentration of serum IgA compared to all groups(P=0.001)except additive SMF(P>0.05;d 21).All the additive groups had lower footpad dermatitis and hock burns compared to CHC(P<0.05).The findings suggest the potential of blended OA as alternatives to BAC to protect broilers from NE indicated by improved FCR,immunity,digestibility,and bird welfare.

Organic acid blends improve intestinal integrity,modulate short-chain fatty acids profiles and alter microbiota of broilers under necrotic enteritis challenge

Controlling enteric diseases of broilers is crucial.Among many additives,organic acids(OA)and their blends are gaining attention to combat diseases in the post-antibiotic era.The current study evaluated the potentials of short-chain fatty acids(SCFA)and medium-chain fatty acids(MCFA)blends and/or phenolic compounds on intestinal integrity,intestinal pH,caecal microbiota,and caecal SCFA profiles of broilers under necrotic enteritis(NE)challenge.The additives used were:(A)a blend of SCFA,MCFA,and a phenolic compound(SMP),(B)a blend of free and buffered SCFA with MCFA(SMF),and(C)a blend of free and buffered SCFA with a high concentration of MCFA(SHM).A total of 1,404 male parental chicks of Ross 308 broilers were randomly allocated to 78 floor pens on hatching day with 6 treatments replicated 13 times with 18 birds per pen.The treatments were:UCC,unchallenged control;CHC,challenged control;BAC,challenged group plus zinc bacitracin;SMP,challenged group plus additive SMP;SMF,challenged group plus additive SMF;SHM,challenged group plus additive SHM.Birds were challenged with field-strain Eimeria spp.on d 9 and Clostridium perfringens on d 14.Birds challenged with NE increased fluorescein isothiocyanate dextran(FITC-d)concentration in serum,reduced acetate and butyrate concentrations,and increased Bacteroides and C.perfringens load in the caeca(P<0.05).Birds fed additives decreased FITC-d from gut to serum,reduced Bacteroides(d 16,P<0.05)and numerically reduced C.perfringens load compared to CHC group.Birds fed additive SHM had higher concentrations of acetate and butyrate(d 21,P<0.05)than CHC group but were not different from SMP and SMF groups.All the additives exhibited similar intestinal protection against NE compared to the BAC group indicated by FITC-d concentration in serum,acetate,propionate and butyrate concentrations in the caeca,and caecal bacterial loads except for the C.perfringens(P>0.05).The SMP group had a higher load compared to BAC(P<0.05).These findings suggest the promising effects of OA blends as alternatives to BAC to ameliorate the impact of NE challenge of broilers as indicated by improved intestinal health.