Influence of an organic acid blend and essential oil blend, individually or in combination, on growth performance, carcass parameters, apparent digestibility, intestinal microflora and intestinal morphology of broilers

Effects of drinking water supplemented with essential oils and organic acids mixtures on growth performance and intestinal health of broilers challenged with necrotic enteritis

It is urgent to develop effective antibiotic alternatives for the control of subclinical necrotic enteritis (NE) in chickens after in-feed antibiotics have been banned. The current study investigated the efficacy of drinking water supplemented with essential oils and organic acids mixtures (EOA) on growth performance and intestinal health of broilers challenged with necrotic enteritis (NE). A total of 360 one-day-old Arbor Acres male broilers were randomly divided into 5 treatment groups, including non-challenged control group (T0), challenged NE group (T1), and challenged NE chickens treated with 0.2 % EOA1 (T2) or 0.2 % EOA2 (T3) in drinking water, along with NE-challenged chickens treated with 45 mg/kg bacitracin methylene disalicylate (BMD) in the diet (T4). Results showed that drinking water supplemented with either EOA1 or EOA2 significantly decreased Clostridium perfringens load in ileal content (P < 0.05). EOA2 markedly reduced jejunal crypt depth, serum lipopolysaccharide (LPS) content, ileal IL-1β mRNA level and myeloperoxidase (MPO) activity, significantly increased Mucin-2 mRNA abundance in ileum of NE infected broilers (P < 0.05) when compared with single NE-infected group. The 16S sequencing analysis revealed that, compared with single NE-challenge group and the antibiotic BMD group, the addition of EOA1 in drinking water significantly increased the Shannon index and Simpson index of ileal microbiota in NE-infected broilers (P < 0.05), while drinking water supplemented with either EOA1 or EOA2 significantly decreased Streptococcus relative abundance of NE-infected broilers (P < 0.05). In summary, drinking water with EOA2 might alleviate the intestinal injury induced by NE challenge, and the gut health-improving effects of EOA2 were better than that of EOA1.

Effects of microencapsulated essential oils and organic acids preparation on growth performance, slaughter characteristics, nutrient digestibility and intestinal microenvironment of broiler chickens

To develop effective antibiotics alternatives is getting more and more important to poultry healthy production. The study investigated the effects of a microencapsulated essential oils and organic acids preparation (EOA) on growth performance, slaughter performance, nutrient digestibility and intestinal microenvironment of broilers. A total of 624 1-day-old male Arbor Acres broilers were randomly divided into 6 groups including the control group (T1) fed with basal diet, the antibiotic group (T2) supplemented with basal diet with 45 mg/kg bacitracin methylene disalicylate (BMD), and 4 inclusion levels of EOA-treated groups (T3, T4, T5, T6 groups) chickens given basal diet with 200, 400, 600, and 800 mg EOA/kg of diet, respectively. Results showed that compared with the control, the 200 mg/kg EOA group increased average daily gain (ADG) and average body weight (ABW) during the early stage (P < 0.05). EOA addition decreased crypt depth of the ileum (P < 0.05), but villus height to crypt depth ratio was increased by EOA addition at 200 and 400 mg/kg at d 21 (P < 0.05). Compared with the control, dietary addition EOA at 200, 400 and 600 mg/kg increased the lipase activity in the duodenum at d 21 (P < 0.05). Increased lactic acid bacteria population was found in cecal digesta of the 400 mg/kg EOA group at d 21 (P < 0.05), and higher concentration of butyric acid level was observed in cecal digesta at d 21 and d 42 in the 200 mg/kg EOA group compared with the control (P < 0.05). RT-PCR analysis found that dietary EOA addition decreased the gene expression of IL-1β, COX-2 and TGF-β4 in the ileum at d 21 (P < 0.05), while only the 200 mg/kg EOA increased the gene expression of IL-10, TGF-β4, Claudin-1, ZO-1, CATH-1, CATH-3, AvBD-1, AvBD-9 and AvBD-12 in the ileum at d 42 (P < 0.05) compared with the control. In summary, adding 200 mg/kg and 400 mg/kg of the EOA to the diet could improve the growth performance and intestinal microenvironment through improving intestinal morphology, increasing digestive enzymes activity and cecal lactic acid bacteria abundance and butyric acid content, improving intestinal barrier function as well as maintaining intestinal immune homeostasis. The improving effect induced by EOA addition in the early growth stage was better than that in the later growth stage. Overall, the EOA product might be an effective antibiotic alternative for broiler industry.

Evaluation of Natural Antimicrobial Substances Blend as a Replacement for Antibiotic Growth Promoters in Broiler Chickens: Enhancing Growth and Managing Intestinal Bacterial Diseases

In recent years, commercial use of antibiotic growth promoter (AGP) has restrictions due to drug resistance against intestinal pathogenic bacteria: Escherichia coli, Salmonella, and Clostridium perfringens. Currently there is no single non-antibiotic treatment approach that is effective against intestinal illnesses in broiler chicken. Hence, present study aimed to analyze efficacy of blend of natural antimicrobial substances (probiotics, prebiotics, organic acids, and essential oils blend named as AGPR) as replacers of AGPs (BMD and CTC) for promoting growth and controlling bacterial diseases in aforementioned three microbes challenged broiler chickens. Effects of treatments (5) and microbes (3) on growth and health performances in experimental birds were analyzed using two factorial ANOVA. Health performance like pathogen loads, morbidity and mortality was considerably reduced by AGPR. Similarly small intestine villi morphometry, nutrition utilization, serum immune response, and carcass yield, was improved significantly by AGPR equivalent to AGPs. Further, growth performance like body weight gain, feed efficiency was also improved by AGPR compared to control but, non-significantly. Among three microbes, E. coli infections had higher morbidity and mortality rates. It was concluded that AGPR blend could be used to improve growth and control the intestinal bacterial infections in broiler chickens as an alternative for AGPs.

Effects of housing systems and feed additive on growth, carcass traits, liver function, oxidative status, thyroid function, and immune parameters of broilers

The effects of rearing Cobb500 broiler chickens under 3 different housing systems (floor litter, floor plastic, and batteries) without or with feed additive (Butinov) on broiler performance, blood parameters and carcass traits were evaluated. Three hundred 1-day-old chicks were distributed in a 3 × 2 factorial arrangement (6 treatments each of 5 replicates). The results showed that reared broilers on litter or plastic floors had high values (P ≤ 0.01) of bird's weight (BW), weight gain (WG), and feed intake (FI) throughout the entire study period (1-42 d of age) compared with rearing on batteries. Rearing broilers in the different housing systems and with or without feed additives did not affect (P ≥ 0.05) total feed conversion (FCR). Different rearing systems or feed additives did not influence broiler chicks' carcass traits and some serum blood parameters. The plastic floor system significantly increased (P ≤ 0.05) blood serum corticosterone compared with litter and batteries. Feed additive (Butinov) decreased the level of T4 (P ≤ 0.05) in blood serum. Plastic floors or batteries significantly increased (P ≤ 0.01) the level of antibody titer against avian influenza virus (HIAV) compared to chicken reared on a litter floor. The results suggested that using housing systems of litter or plastic floors could improve broiler growth performance without adversely affecting carcass traits and blood characteristics compared with rearing in batteries. Also, broiler diets' feed additive (Butinov) and their interaction with rearing systems did not improve broiler growth performance.

Growth performance, carcass characteristics, and blood biochemical indices of broilers affected by dietary organic acids blend's supplementation

The objective of the present study was to explore the influence of organic acids cocktail (lactic-L plus formic-F acid, LF) in broiler diets on feed utilization, growth rate, blood indices and carcass traits. A total of 300 chicks were used and allotted to five treatment groups. The rations contained 0 additives (negative control-NC), basal diet + 0.5 g Colistin® (positive control-PC); LF2, LF4 and LF6: basal diet + 2, 4 and 6 cm3 LF/kg diet, respectively. There were no differences in feed consumption and feed conversion due to LF treatments at all ages except FI at 1-2 wks of age which was significantly affected by gradual levels of LF (p < 0.05). All carcass traits were statistically significant (p < 0.05) differed due to LF treatments. The alterations in urea, creatinine total protein, globulin and albumin in addition to the activity of alanine aminotransferase and aspartate aminotransferase in broiler chicks were significantly different when compared to controls. Malondialdehyde (MDA) slightly decreased with an increase in the level of formic plus lactic. Based on our results, the highest and middle levels (6 and 4 cm3 LF/kg diet) are recommended for the best performance and health aspects of broilers.

The use of thymol, carvacrol and sorbic acid in microencapsules to control Salmonella Heidelberg, S. Minnesota and S. Typhimurium in broilers

Introduction

The control of Salmonella spp. in poultry involves different biosecurity actions and lately has been complicated by the emergence of multidrug resistant serovars. The application of organic acids and essential oils has been used with different approaches due to the antibacterial properties as food preservatives. The use of these molecules in animal feed to control enteric pathogens is a major interest within the poultry industry.

Methods

The use of a blend containing nature-identical compounds of sorbic acid (25%), thymol (9.5%) and carvacrol (2.5%) microencapsulated in a lipid matrix, was investigated in the present work, for the control of three Salmonella serovars (S. ser. Typhimurium, S. ser. Heidelberg and S. ser. Minnesota). Commercial broilers were challenged at 3 or at 33 days of age. Groups SH-1, SM-1 and ST-1, received treatment in the feed, at 2 kg/ton from 1-21 days of age and at 1 kg/ton from 35-42 days of age (last week), while groups SH-2, SM-2 and ST-2, were treated only during the last week receiving 2 kg/ton. Each treated group had an untreated control group, that was challenged at the same moment with the respective serovar (groups PCH, PCM and PCT). The challenge strains were enumerated in liver and cecal contents, weekly after challenge, at 7, 14, 21, 28, 35 and 42 days-of-age.

Results and discussion

Significant reduction was noticed at 7 and 14 days of age in all groups that received treatment during the initial phase (p < 0.05). Moreover, the body weight was significantly higher at the last experimental day (p < 0.05) in chickens that received treatment at the initial and at the final growth stages.

Dietary coated essential oil and organic acid mixture supplementation improves health of broilers infected with avian pathogenic Escherichia coli

Colibacillosis caused by avian pathogenic Escherichia coli (APEC) is a very prevalent disease in poultry farms in China. The exploration of effective non-antibiotic substances is of great significance for the control of APEC infections. This experiment evaluated the efficacy of coated essential oil and organic acid (EOA) supplementation to prevent E. coli O78 infection in broiler chickens. A total of 288 one-day-old male broiler chicks were randomly distributed into 4 groups with 6 replicates per group. Chickens were fed a diet either supplemented with EOA (500 mg/kg feed) or not, and either uninfected or infected with E. coli O78 intratracheally. Results showed that E. coli O78 infection reduced body weight gain, increased mortality and the ratio of feed to gain along with cecal and liver E. coli load, damaged gut mucosa, induced local and systemic inflammation, and altered cecal microbial composition, diversity and function (P < 0.05). Supplemental EOA improved feed conversion efficiency, lowered gross lesion scores and cecal E. coli population, enhanced intestinal goblet cells and serum IgG concentration, and tended to decrease serum IL-12 production (P < 0.05). Essential oil and organic acid addition downregulated IFN-γ mRNA, tended to decrease mucin-2 mRNA levels while upregulating IL-10 mRNA, and tended to increase ZO-1 gene expression in the jejuna of infected birds at 7 d after E. coli O78 challenge (P < 0.05). The 16S rRNA gene sequencing indicated that both EOA addition and E. coli O78 challenge altered the diversity and composition of the cecal microbiota community. Furthermore, infected birds fed EOA showed decreased Bacteroidetes and genus Lactobacillus abundance compared with the infected control. LEfSe analysis showed that Firmicutes, Ruminococcaceae, Clostridiales, Clostridia, Lactobacillus, Lactobacilaceae, and cc-115 were enriched in the non-infected but EOA-treated group (P < 0.05). Collectively, dietary EOA supplementation could mildly alleviate E. coli-induced gut injury and inflammation.

Performance of broiler chicken on dietary supplementation of protected organic acids blend

1. The fatty acid coated organic acids blend was evaluated for its potential as a growth promoter.2. A six-week experiment was conducted following a completely randomised design. One-day old broiler chicks (n=384) were randomly divided into four dietary groups (eight replicates per group). Diet treatments were an unsupplemented basal diet or containing 0.3, 0.6, and 1 g/kg of a coated organic acid blend. Birds were evaluated for growth performance, carcass traits, immune-competence, total viable count, and gut villus height.3. The broiler chickens fed with 1 g/kg organic acids blend showed significantly higher body weight gain with improved feed conversion ratio and lower mortality than those fed the basal diet.4. The carcass traits vis. eviscerated yield, dressing percentage, breast yield and relative weight of giblets, were significantly better in the group fed with 1 g/kg coated organic acids blend with reduction in abdominal fat.5. Significantly higher cell-mediated, humoral immune responses and villi height with higher lymphoid organ weight (bursa and thymus) and a significant decrease in the total viable count were recorded in birds fed 1 g/kg organic acids blend.6. The results indicated that dietary inclusion of coated organic acids blend (1 g/kg) improved growth performance, carcass traits, immunity, and gut health in broiler chicken and reduced total viable count and abdominal fat, indicating its potential role as a promising growth promoter in poultry.

Effect of blending encapsulated essential oils and organic acids as an antibiotic growth promoter alternative on growth performance and intestinal health in broilers with necrotic enteritis

The effects of a blend of encapsulated organic acids with essential oils (EOA) as an alternative to antimicrobial growth promoter (AGP) on growth performance and gut health of Eimeria spp./Clostridium perfringens (C. perfringens) in chickens infected with necrotic enteritis (NE) broilers was investigated. A total of 432 male Arbor Acres broilers (1-day-old) were randomly distributed into 6 treatment groups, namely noninfected negative control (A); NE-infected positive control (D); NE-infected broiler chickens fed a basal diet supplemented with 250 mg/kg bacitracin methylene disalicylate (BMD) plus 90 mg/kg monensin; and NE-infected broiler chicken fed 200; 500; and 800 mg/kg EOA (E, F, G, and H group). Feeding EOA at 200 and 500 mg/kg considerably improved the feed conversion ratio, reduced gut lesions, serum fluorescein isothiocyanate dextran level, and C. perfringens load in the caecum and liver of the NE-infected broiler chickens. This feed was similar to AGP. Furthermore, the increased villous height-to-crypt depth ratio and goblet cells counts, upregulated claudin-1, glucagon-like peptide-2 (GLP-2), insulin-like growth factor-2 (IGF-2) mRNA gene expression, downregulated occludin, zonula occludens-1 (ZO-1), toll-like receptor (TLR-4), interleukin (IL-1β), interferon γ (IFN-γ), TNF receptor-associated factor 6 (TRAF-6), tumor necrosis factor superfamily member 15 (TNFSF15), and Toll-interacting protein (Tollip) genes expression in the jejunum were observed in the NE-infected broiler chickens that received EOA at 200 and 500 mg/kg compared with those of the single NE-challenged groups without EOA supplementations (P < 0.05). The 16S analysis revealed that EOA supplemented with 200 or 500 mg/kg enriched relative abundance of Lactobacillus, unclassified_Lachnospiraceae, and Enterococcus, and carbohydrate metabolic pathways but suppressed unclassified_Erysipelotrichacease and organismal systems involved in the immune system (P < 0.05). Feeding EOA could alleviate NE-induced gut impairment and growth depression and modulate cecal microbiota composition, which has potential as antimicrobial alternatives.

Effect of organic acids-essential oils blend and oat fiber combination on broiler chicken growth performance, blood parameters, and intestinal health

This study evaluated the effect of organic acids-essential oils blend with or without oat hulls (OH) on growth performance, organ weights, blood parameters, gut morphology, microbiota, and short-chain fatty acids (SCFA) in broiler chickens. Day-old broiler chickens were randomly allocated to 4 dietary treatments consisting of 1) a corn-soybean meal-wheat based diet (BAS), 2) BAS + 0.05% bacitracin methylene disalicylate (BMD), 3) BAS + protected organic acids-essential oils at 300 g/1,000 kg of feed (OE), and 4) BAS + protected organic acids-essential oils at 300 g/1,000 kg of feed + 3% OH (OEOH), in 8 replicate groups. Feeding was in starter (d 0 to 14), grower (d 14 to 24), and finisher (d 24 to 36) phases. Body weight (BW), feed intake (FI), feed conversion ratio (FCR), and mortality were determined weekly. On d 36, 8 chickens per treatment were sampled for blood biochemistry, organ weights, cecal SCFA production, and microbiota. Treatments had no effect on FI and FCR at all phases. Both OE and OEOH treatments reduced (P < 0.001) the body weight gain of birds at the starter phase. Birds fed the OEOH treatment had higher (P < 0.001) gizzard weight, while those offered the BMD diet showed a tendency (P = 0.08) to have higher cecal weight. Birds in the OEOH treatment recorded increased ileal villus height and villus height-to-crypt depth ratio, as well as reduced duodenal crypt depth, while birds in the OE treatment had increased jejunal villus height and villus height-to-crypt depth ratio. Both OEOH and OE treatments increased the number of goblet cells produced in the duodenum and jejunum. Treatments had no effect on SCFA concentrations. Birds in the OE treatment recorded the lowest concentration of blood urea (P = 0.05) and cholesterol (P < 0.05). Both OE and OEOH treatments increased (P < 0.05) the relative abundance of potentially beneficial bacteria in the genus Firmicutes_unclassified, Ruminococcus, Turicibacter, and Erysipelotrichaceae_unclassified, while reducing (P < 0.001) the relative abundance of potentially harmful Coprobacillus. Conclusively, both protected organic acids-essential oils blend and its combination with oat fibers show potential as tools to achieve antibiotics reduction in broiler production.

The Concentration of Organic Acids in Cranberry Juice Modulates the Gut Microbiota in Mice

A daily consumption of cranberry juice (CJ) is linked to many beneficial health effects due to its richness in polyphenols but could also awake some intestinal discomforts due to its organic acid content and possibly lead to intestinal inflammation. Additionally, the impact of such a juice on the gut microbiota is still unknown. Thus, this study aimed to determine the impacts of a daily consumption of CJ and its successive deacidification on the intestinal inflammation and on the gut microbiota in mice. Four deacidified CJs (DCJs) (deacidification rates of 0, 40, 60, and 80%) were produced by electrodialysis with bipolar membrane (EDBM) and administered to C57BL/6J mice for four weeks, while the diet (CHOW) and the water were ad libitum. Different parameters were measured to determine intestinal inflammation when the gut microbiota was profiled. Treatment with a 0% DCJ did not induce intestinal inflammation but increased the gut microbiota diversity and induced a modulation of its functions in comparison with control (water). The effect of the removal of the organic acid content of CJ on the decrease of intestinal inflammation could not be observed. However, deacidification by EDBM of CJ induced an additional increase, in comparison with a 0% DCJ, in the Lachnospiraceae family which have beneficial effects and functions associated with protection of the intestine: the lower the organic acid content, the more bacteria of the Lachnospiraceae family and functions having a positive impact on the gut microbiota.

Supplementation of Mixed Organic Acids Improves Growth Performance, Meat Quality, Gut Morphology and Volatile Fatty Acids of Broiler Chicken

Simple Summary

Organic acid as a green feed additive is increasingly favoured by enterprises and scholars, but little emphasis has been placed on the effect of organic acids on broiler meat quality and lipid profile. Therefore, this study observed that mixed organic acids improve broiler growth performance, meat quality as well as muscle lipid profile, which suggests that mixed organic acids can be an effective measure to prevent meat quality decline in chicken meat.

Abstract

Background: Organic acid as a green feed additive is increasingly favoured by enterprises and scholars, but little emphasis has been placed on the effect of organic acids on broiler meat quality. Methods: A total of 192 male chicks (one-day-old, weighted 48.40 ± 0.64 g) were selected to investigate the effect of mixed organic acids (MOA) on growth performance, meat quality as well as fatty acids profile. Chicks were randomly allocated to three treatments with eight replicates and eight chicks per replicate, including a corn–soybean basal diet with 0 (CON), 3000 mg/kg (low MOA; LMOA), and 6000 mg/kg (high MOA; HMOA) MOA. The experiment was divided into starter (d 1–d 21) and grower (d 22–d 42) phases. Results: Broilers supplemented with LMOA and HMOA enhanced (p < 0.05) the final body weight and average daily gain in the grower and overall phases. An improved (p < 0.05) feed conversion ratio in the grower and overall phases was observed in broilers supplemented with LMOA. The breast and thigh muscles pH24h were higher (p < 0.05) in broilers fed with HMOA and the redness in thigh meat was also improved (p < 0.05). Additionally, supplementing LMOA increased (p < 0.05) the saturated fatty acids, unsaturated fatty acids and the ratio of polyunsaturated fatty acids to saturated fatty acids in breast meat. A positive effect occurred (p < 0.05) on jejunal villus height and ileal crypt depth in 21 d broilers supplemented with HMOA. Conclusion: Our findings indicated that dietary supplementation of MOA could improve the growth performance, meat quality, and fatty acids profile, as well as intestinal morphology. Furthermore, diets supplemented with mixed organic acids at 3000 mg/kg may be more desirable, considering the overall experimental results in broilers.

Are There Effective Intervention Measures in Broiler Production against the ESBL/AmpC Producer Escherichia coli?

Extended-spectrum beta-lactamase (ESBL) and AmpC beta-lactamase (AmpC) producing Enterobacteriaceae occur frequently in livestock animals and the subsequent stages of the meat production chain and are therefore considered a risk for human health. Strict biosecurity measures and optimal farm management should reduce or even prevent poultry flock colonization at farm level. This review summarizes and evaluates published information on the effectiveness of specific intervention measures and farm management factors aiming to reduce the occurrence and spread of ESBL/AmpC producing or commensal or pathogenic E. coli in broiler chicken farms. In this systematic literature review, a total of 643 publications were analyzed, and 14 studies with significant outcome about the effectiveness of specific measures against E. coli and ESBL/AmpC producing E. coli in broiler chicken farms were found. Different feed additives seem to have an impact on the occurrence of those microorganisms. The measures ‘cleaning and disinfection’ and ‘competitive exclusion’ showed strong effects in prevention in some studies. In summary, some intervention measures showed potential to protect against or eliminate ESBL/AmpC-producing, commensal or pathogenic E. coli at farm level. Due to the high variability in the outcome of the studies, more specific, detailed investigations are needed to assess the potential of the individual intervention measures.

Probiotics and Herbs Combination in Commercial Feed Additives as Growth Promoter in Broiler Chicken

The prohibition on the use of Antibiotic Growth Promoter (AGP) causes the use of probiotics, herbs, enzymes and organic acids as an alternatives to AGP. This study aimed to determine the role of combination of probiotic and herbs in commercial feed additives on broiler performance. Sixty day-old male broiler were divided into 3 groups where each group consisted of 20 chickens with 4 replication each group. Group I was given commercial feed, group II was given commercial feed + AGP and group III was given commercial feed + combination of probiotics, herbs, enzymes and organic acids. All chickens were kept for 5 weeks. Body weight gain (BWG), body weight (BW) and Feed Convertion Ratio (FCR) were calculated every week. Carcass percentage was calculated at week 5. The results obtained from BWG and BW on group III at weeks 4 and 5 weeks were higher and significant difference (P<0.05) compared to groups I and II. The percentage of carcasses between groups did not have a significant difference (P>0.05). FCR values in group III from week 1 to weeks 5 were lower than groups I and II. The use of combination of probiotics, herbs, enzymes and organic acids has proven to have a good role on broiler performance so that it can replace AGP as a feed additive on broiler.

Essential oils as growth-promoting additives on performance, nutrient digestibility, cecal microbes, and serum metabolites of broiler chickens: a meta-analysis

OBJECTIVE

The purpose of this meta-analysis was to evaluate the effect of dietary essential oils (EOs) on productive performance, nutrient digestibility, and serum metabolite profiles of broiler chickens and to compare their effectiveness as growth-promoting additives against antibiotics.

METHODS

Peer-reviewed articles were retrieved from Web of Science, Science Direct, PubMed, and Google scholar and selected based on pre-determined criteria. A total of 41 articles containing 55 experiments with 163 treatment units were eligible for analyses. Data were subjected to a meta-analysis based on mixed model methodology considering the doses of EOs as fixed effects and the different studies as random effects.

RESULTS

Results showed a linear increase (p<0.001) on body weight gain (BWG) where Antibiotics (FCR) and average daily feed intake decreased (p<0.001) linearly with an increasing dose of EOs. Positive effects were observed on the increased (p<0.01) digestibility of dry matter, crude protein, ether extract, and cecal Lactobacillus while Escherichia coli (E. coli) population in the cecum decreased (p<0.001) linearly. There was a quadratic effect on the weight of gizzard (p<0.01), spleen (p<0.05), bursa of fabricius (p<0.001), and liver (p< 0.10) while carcass, abdominal fat, and pancreas increased (p<0.01) linearly. The dose of EOs linearly increased high density lipoprotein, glucose, protein, and globulin concentrations (p<0.01). In comparison to control and antibiotics, all type of EOs significantly reduced (p<0.001) FCR and tended to increase (p<0.1) BWG and final body weight. Cinnamaldehyde-compound was the only EOs type showing a tendency to increase (p<0.1) carcass weight, albumin, and protein of serum metabolites while this EOs together with EOs-Blend 1 decreased (p<0.01) E. coli population. Low density lipoprotein concentration decreased (p<0.05) with antibiotics and carvacrol-based compound when compared to the control group.

CONCLUSION

This evidence confirms that EOs are suitable to be used as growth promoters and their economical benefit appears to be promising.

Effects of dietary supplementation with herbal extract mixture on growth performance, organ weight and intestinal morphology in weaning piglets

BACKGROUND

Many countries are increasingly prohibiting the addition of antibiotics in livestock diets. Therefore, herb extracts have gradually drawn attention to substitute antibiotics. Our present study aimed to determine the effects of herbal extract mixture (HEM) in dietary on growth performance, organ weight, intestinal morphology and intestinal nutrient transporters in weaned pigs.

METHODS

27 piglets (Duroc × [Landrace × Yorkshire]; Body Weight (BW) = 5.99 ± 0.13 kg) were weaned at day 21 and randomly divided into three groups (n = 9 piglets/group). All piglets received a basal diet containing similar amounts of nutrients for 14 days. The three groups were the control (no additive), the antibiotics (375 mg/kg chlortetracycline, 20%, 500 mg/kg enramycin, 4%, 1,500 mg/kg oxytetracycline calcium, 50%) and the HEM group (1000 mg/kg extract mixture of golden-and-silver honeysuckle, huangqi, duzhong leaves and dangshen). After 14 d of treatment, we collected tissue samples to measure organ weight, intestinal parameters, intestinal morphology, digestive enzyme activities and intestinal mRNA expression of nutrient transporters.

RESULTS

The HEM group had no effects on growth performance and organ weight of weaned pigs. But compared with the control group, both HEM and antibiotics improved intestinal morphology, and HEM elevated the expression of nutrient transporters in ileum (SLC6A9, SLC15A1, and SLC5A1). HEM significantly decreased the activities of maltase in ileum and the ratio of small intestinal weight to BW than control group.

CONCLUSIONS

These results indicate benefit effects of the supplementation of HEM in diet, including modulating intestinal morphology and increasing the mRNA expression of nutrients transporters. These findings suggest that HEM provides novel insights into a variety of herbal extract mixtures to replace antibiotics in animal production.

The dietary combination of essential oils and organic acids reduces Salmonella enteritidis in challenged chicks

This study was conducted to determine the effects of essential oils and organic acids (EOA) on Salmonella Enteritidis (S. Enteritidis) challenged chickens. One-day-old specific pathogen-free (SPF) chicks (250) were randomly assigned to 5 groups, with 50 birds in each group. The treatment groups were as follows: 1) basal diet, negative control group (NC); 2) basal diet + S. Enteritidis, positive control group (PC); 3) PC + 4,000 g/t of enrofloxacin (5%), antibiotic group (ENR); 4) PC + 800 g/t of EOA1, thymol-benzoic acid group (TBA); and 5) PC + 800 g/t of EOA2, cinnamylaldehyde-caproic acid group (CCA). At 7 D of age, each bird, except those in NC, was orally gavaged with 0.4 mL of a suspension of 4.4 × 10⁹ cfu S. Enteritidis/mL. Results revealed that ENR reduced bacterial counts in the liver and spleen on days 3, 5, and 7 post-challenge more (P < 0.05) than any other treatments. However, bacterial counts in cecal contents among ENR, TBA, and CCA were similar at 5 and 7 D post-challenge but lower than those of PC. Additionally, the bacterial counts in liver, spleen, and cecum contents in TBA were lower (P < 0.05) than in PC at 3, 5, and 7 D post-challenge; the bacterial counts in spleen contents in TBA were lower (P < 0.05) than in CCA at 7 D post-challenge. Tumor necrosis factor-α contents in TBA and CCA were lower (P < 0.05) than those in PC. Also, the ratio of villus height to crypt depth in the ileum of CCA was higher (P < 0.05) than that of PC and ENR; however, there was no difference in the secretory IgA content of the jejunum among the groups. In conclusion, EOA had a bacteriostatic effect on S. Enteritidis, and the effect of the thymol-benzoic acid complex surpassed that of the cinnamaldehyde-caproic acid complex. Therefore, EOA may act as an effective antibiotic substitute for animals in the prevention and treatment of Salmonella.

Effects of benzoic acid, Bacillus coagulans and oregano oil combined supplementation on growth performance, immune status and intestinal barrier integrity of weaned piglets

This experiment was conducted to investigate the effects of benzoic acid, Bacillus coagulans and oregano oil combined supplementation on growth performance, immune status and intestinal barrier integrity of piglets. In a 26-d experiment, 25 piglets were randomly assigned to 5 treatments: 1) a basal diet, negative control (NC), 2) NC added with antibiotics, positive control (PC); 3) NC added with benzoic acid at 3,000 g/t and Bacillus coagulans at 400 g/t (AB); 4) NC added with benzoic acid at 3,000 g/t and oregano oil at 400 g/t (AO); 5) NC added with 3,000 g/t benzoic acid and Bacillus coagulans at 400 g/t and oregano oil at 400 g/t (ABO). On d 27, all piglets were euthanized to obtain jejunal mucosa to measure immune status and intestinal barrier integrity. Results showed that pigs fed AB diet increased the final body weight and average daily body weight gain and decreased the ratio of feed to gain compared with NC group (P < 0.05). Compared with NC group, AB, AO and ABO decreased serum tumor necrosis factor-α concentration and ABO decreased interleukin-1β concentration in serum and jejunal mucosa (P < 0.05). Compared with NC group, AB up-regulated mRNA expressions of sodium-glucose cotransporte1, claudin-1, occludin and mucin2 in jejunal mucosa and the populations of Bifidobacterium and Bacillus in cecal digesta (P < 0.05). Compared with NC group, ABO increased jejunal mucosal occludin mRNA abundance and Bifidobacterium population in cecal digesta, and decreased Escherichia coli population in cecal digesta (P < 0.05). Furthermore, AB and ABO increased Bacillus population in cecal digesta compared with PC group (P < 0.05). These results indicated that dietary AB supplementation could improve growth performance and intestinal barrier integrity of piglets when fed antibiotic-free diets, which was possibly associated with the improvement of immune status and intestinal microflora. Dietary ABO supplementation is also beneficial to improve immune status and intestinal barrier integrity and microflora of piglets.

Role of acidifiers in livestock nutrition and health: A review

Ever since the European ban on use of in-feed antibiotics in food animals, the search for alternate antibiotic-free growth promoter is undertaken worldwide. There are few alternatives such as probiotics, pre-biotics, phytochemicals, enzymes and organic acids. Among these alternatives, the organic acids or simply acidifiers play an important role in gut health in animals. The acidifiers could be used to favourably manipulate the intestinal microbial populations and improve the immune response, hence perform an activity similar to antibiotics in food animals in countering pathogenic bacteria. Acidifiers also improve the digestibility of nutrients and increase the absorption of minerals. The incorporation of organic acids also leads to thinning of the intestinal lining which facilitates better absorption of nutrients and its efficient utilization. However, their effect will not be similar among all types of organic acids as their mechanism of activity is based on its pKa value. Moreover, there are claims about the neutralization of acids by the secretion of bicarbonates in the initial part of intestine, reactivity with metallic items in feed mills and reduced palatability due its bitter taste demands non-reactive and targeted delivery for better performance. Currently, coated salts of acidifiers are available commercially for use in food animals especially pigs and poultry. The present review highlights the role of different acidifiers in livestock nutrition with their potent applications in improving nutrient digestibility, mineral utilization, meat quality, enhancing immunity, antimicrobial effects in countering pathogenic bacteria, boosting performance and production, and thus safeguarding health of livestock animals and poultry.

Protective Effects of Benzoic Acid, Bacillus Coagulans, and Oregano Oil on Intestinal Injury Caused by Enterotoxigenic Escherichia coli in Weaned Piglets

The use of antibiotics as growth promoters in feed has been fully or partially banned in several countries. The objective of this study was to investigate the effects of benzoic acid (A), bacillus coagulans (B) and oregano oil (O) combined supplementation on growth performance and intestinal barrier in piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty piglets were randomly assigned to 6 treatments: (1) nonchallenged control (CON); (2) ETEC-challenged control (ETEC); (3) antibiotics + ETEC (AT); (4) A + B + ETEC (AB); (5) A + O + ETEC (AO); (6) A + B + O + ETEC (ABO). On day 22, piglets were orally challenged with ETEC or saline. The trial lasted 26 days. Dietary AO and ABO inhibited the reduction of growth performance and the elevation of diarrhoea incidence in piglets induced by ETEC (P<0.05). AB, AO, and ABO prevented the elevation of serum TNF-α and LPS concentrations in piglets induced by ETEC (P<0.05). ABO alleviated the elevation of TNF-α and IL-1β concentrations and the reduction of sIgA level in jejunal mucosa induced by ETEC (P<0.05). Furthermore, ABO upregulated mRNA expressions of Claudin-1 and Mucin2 (P<0.05), downregulated mRNA abundances of TLR4 and NOD2 signaling pathways related genes in jejunal mucosa (P<0.05), and improved the microbiota in jejunal and cecal digesta (P<0.05) compared with ETEC group. These results indicated that benzoic acid, bacillus coagulans, and oregano oil combined supplementation could improve growth performance and alleviate diarrhoea of piglets challenged with ETEC via improving intestinal mucosal barrier integrity, which was possibly associated with the improvement of intestinal microbiota and immune status. The combination of 3000 g/t benzoic acid + 400 g/t bacillus coagulans + 400 g/t oregano oil showed better effects than other treatments in improving growth performance and intestinal health of piglets, which could be used as a viable substitute for antibiotic.

Fermented soybean meal exhibits probiotic properties when included in Japanese quail diet in replacement of soybean meal

This study was conducted to investigate and compare the effect of dietary probiotic mixture (PM) and organic acid (OA) mixture with fermented soybean meal (FSBM) on performance, crop, and ceca microbiota, small intestine morphology, and serum lipid profile in Japanese quails. A total of 800 day-old Japanese quails was randomly allotted to 5 treatments with 8 replicate pens of 20 birds each, for 35 days. The experimental diets consisted of a control corn-soybean meal diet and 4 test diets: 1) control diet + 0.1% PM; 2) control diet + 0.2% OA mixture; 3) control diet + the combination of both PM and OA; and 4) an additives-free diet in which the soybean meal in the control diet was replaced with FSBM. The results indicated that in starter and the entire rearing periods, FSBM, PM, and PM+OA diets had significantly lower FCR compared to control or OA diets (P < 0.05). Birds in the FSBM group gained higher weight than control and OA birds (P < 0.05; 1 to 35 d). At d 21 and 35, birds fed the control diet showed significantly lower numbers of lactic acid bacteria in the crop, while coliforms were higher in the cecal content compared to the other diets (P < 0.05). At d 21, the villus height and villus height to crypt depth ratio in the duodenum and jejunum of birds fed PM, PM+OA, and FSBM diets were greater than in other treatments (P < 0.05). The serum concentrations of cholesterol and low-density lipoprotein cholesterol of birds fed PM, PM+OA, and FSBM diets were significantly lower than birds in control and AO groups (P < 0.05). The results obtained herein suggest that FSBM exhibits probiotic properties and, when used in substitution of SBM in Japanese quail diet, can improve growth performance, balance of desirable gastrointestinal microbiota in crop and ceca, small intestinal morphology, and serum lipid profile-likewise, a probiotic supplement.

Essential oils as alternatives to antibiotics in swine production

This review article summarizes the efficacy, feasibility and potential mechanisms of the application of essential oils as antibiotic alternatives in swine production. Although there are numerous studies demonstrating that essential oils have several properties, such as antimicrobial, antioxidative and anti-inflammatory effects, feed palatability enhancement and improvement in gut growth and health, there is still a need of further investigations to elucidate the mechanisms underlying their functions. In the past, the results has been inconsistent in both laboratory and field studies because of the varied product compositions, dosages, purities and growing stages and conditions of animals. The minimal inhibitory concentration (MIC) of essential oils needed for killing enteric pathogens may not ensure the optimal feed intake and the essential oils inclusion cost may be too high in swine production. With the lipophilic and volatile nature of essential oils, there is a challenge in effective delivery of essential oils within pig gut and this challenge can partially be resolved by microencapsulation and nanotechnology. The effects of essential oils on inflammation, oxidative stress, microbiome, gut chemosensing and bacterial quorum sensing (QS) have led to better production performance of animals fed essential oils in a number of studies. It has been demonstrated that essential oils have good potential as antibiotic alternatives in feeds for swine production. The combination of different essential oils and other compounds (synergistic effect) such as organic acids seems to be a promising approach to improve the efficacy and safety of essential oils in applications. High-throughput systems technologies have been developed recently, which will allow us to dissect the mechanisms underlying the functions of essential oils and facilitate the use of essential oils in swine production.