Effects of maize naturally contaminated with aflatoxin B1 on growth performance, intestinal morphology, and digestive physiology in ducks

Limosilactobacillus reuteri peptidoglycan alleviates aflatoxin B1-induced toxicity through adsorbing toxins and improving growth, antioxidant status, immunity and liver pathological changes in chicks

1. The objective of this study was to investigate the protective effects of a peptidoglycan produced by Limosilactobacillus reuteri against aflatoxin B1 (AFB1) induced toxicity in vitro and in vivo in broiler chicks.2. Toxin adsorption experiments were carried out firstly in vitro. These experiments indicated that the absorption efficiency of the peptidoglycan for AFB1 was 64.3-75.9%.3. In the in vivo experiments, Hy-Line Brown chicks were fed a diet containing AFB1 at 71.43 µg/kg with and without peptidoglycan supplementation at concentrations of 100, 200, or 300 g/kg feed from 0-42 d of age.4. The peptidoglycan supplementation in AFB1-contaminated diets resulted in significant improvements in terms of average daily gain, feed intake, feed conversion ratio, white blood cell count, haemoglobin content, glutathione peroxidase activity, immunoglobulin (Ig) A, IgG, IgM and Newcastle disease virus antibody titres (p < 0.05) and diminished liver steatosis.5. In conclusion, peptidoglycan supplementation alleviated AFB1-induced toxicity through adsorbing toxins and improving growth performance, antioxidant ability, immunity and liver pathological changes in chicks. The optimal supplemental dose was 200 mg/kg in feed.

Effects of dietary supplement of ε-polylysine hydrochloride on laying performance, egg quality, serum parameters, organ index, intestinal morphology, gut microbiota and volatile fatty acids in laying hens

BACKGROUND

ε-polylysine hydrochloride (ε-PLH) is a naturally occurring antimicrobial peptide extensively utilized in the food and medical industries. However, its impact on animal husbandry remains to be further explored. Therefore, the present study aimed to determine the effect of ε-PLH on laying hens' health and laying performance.

RESULTS

Dietary supplementation with ε-PLH to the diet significantly increased average egg weight during weeks 1-8. Meanwhile, compared with the control group, supplementation with ε-PLH decreased the feed egg ratio during weeks 9-12 and egg breakage rate during weeks 9-16 ，whereas it increased eggshell strength during weeks 1-4 and 13-16 . The ε-PLH 0.05% group increased yolk percentage during weeks 5-8 and yolk color during weeks 1-4 . Furthermore, ε-PLH supplementation significantly increased the concentrations of total protein, albumin, globulin and reproductive hormones estradiol, as well as decreased interleukin-1 beta and malondialdehyde in the serum. Compared with the control group, supplementation with 0.05% ε-PLH significantly increased the relative abundance of Cyanobacteria and Gastranaerophilales and decreased the abundance of Desulfovibrio and Streptococcus in the cecum microbiota. In addition, ε-PLH 0.1% supplementation also increased acetic acid content in the cecum.

CONCLUSION

Dietary supplementation with ε-PLH has a positive impact on both productive performance and egg quality in laying hens. Furthermore, ε-PLH can also relieve inflammation by promoting the immunity and reducing oxidative damage during egg production. ε-PLH has been shown to improve intestinal morphology, gut microbial diversity and intestinal health. © 2023 Society of Chemical Industry.

Protective effects of polydatin on ileum injury in mice exposed to aflatoxin B1

Aflatoxin B1 (AFB1) is an extremely hazardous food/feed pollutant, posing a serious threat to health of human and animals. Particularly, exposure to AFB1 provokes enterocytes oxidative stress and inflammation, which lead to intestinal damage. Polydatin (PD), a stilbenoid glucoside, is known to possess antioxidant and anti-inflammatory properties and is being investigated for use in various disorders. The present study was intended at investigating the protective efficacy of polydatin against AFB1-induced ileum damage in mice. Kunming male mice received oral gavage of AFB1 (300 μg/kg) and PD (100 mg/kg) for 18 days. The results showed that mice exposed to AFB1 exhibited the impaired morphology, the suppressed disaccharidase activities, the down-regulated mRNA expressions of tight junction protein genes, oxidative stress, inflammation and the up-regulated mRNA expressions of genes related to mitophagy in the ileum, whereas PD treatment reversed the AFB1-induced disruption of ileal structure, digestion, barrier function, redox and immune status. The findings of the present study suggested that polydatin may have a potential benefit in preventing AFB1-induced ileum damage.

Crosstalk between Mycotoxins and Intestinal Microbiota and the Alleviation Approach via Microorganisms

Mycotoxins are secondary metabolites produced by fungus. Due to their widespread distribution, difficulty in removal, and complicated subsequent harmful by-products, mycotoxins pose a threat to the health of humans and animals worldwide. Increasing studies in recent years have highlighted the impact of mycotoxins on the gut microbiota. Numerous researchers have sought to illustrate novel toxicological mechanisms of mycotoxins by examining alterations in the gut microbiota caused by mycotoxins. However, few efficient techniques have been found to ameliorate the toxicity of mycotoxins via microbial pathways in terms of animal husbandry, human health management, and the prognosis of mycotoxin poisoning. This review seeks to examine the crosstalk between five typical mycotoxins and gut microbes, summarize the functions of mycotoxins-induced alterations in gut microbes in toxicological processes and investigate the application prospects of microbes in mycotoxins prevention and therapy from a variety of perspectives. The work is intended to provide support for future research on the interaction between mycotoxins and gut microbes, and to advance the technology for preventing and controlling mycotoxins.

Aflatoxin B1 disrupts the intestinal barrier integrity by reducing junction protein and promoting apoptosis in pigs and mice

With the growing diversity and complexity of diet, animals and humans are at risk of exposure to aflatoxin B1 (AFB1), which is a well-known contaminant in the food chain that causes various toxicological effects. The intestine acts as the first barrier against external contaminants, but the effect of AFB1 on intestinal barrier has not been determined. This study aimed to evaluate AFB1 on the intestinal barrier function in vitro and in vivo. In vitro, porcine jejunal epithelial cells (IPEC-J2) were treated with increasing concentrations of AFB1 (10-60 mg/L). In vivo, Kunming (KM) mice were used as controls or gavaged with 1% dimethyl sulfoxide (110 mg/kg b.w.) and AFB1 (0.3 mg/kg b.w.) for 28 days. In IPEC-J2 cells, the cell viability decreased with increasing mycotoxin concentrations, and the viability of IPEC-J2 cells decreased significantly (P < 0.05) when the AFB1 concentrations were greater than 30 mg/L. In addition, quantitative real-time PCR, Western blot analysis, and immunofluorescence results show that AFB1 can downregulate the tight junction proteins and increase the expression levels of Caspase-3 and the ratio of Bax/Bcl-2, suggesting that AFB1 was cytotoxic to IPEC-J2. In vivo, the ratio of villus height to crypt depth, the intestinal wall thickness, the number of intestinal villus per 1000 µm in the jejunum, the expression levels of ZO-1, Claudin-3, Occludin, MUC2, and Caspase-3, and the ratio of Bax/Bcl-2 were significantly affected in mice exposed to AFB1. In vitro and in vivo results showed that the effects of exposure to AFB1 on the intestinal function in the jejunum of KM mice and in the IPEC-J2 was similar, suggesting that AFB1 may adversely affect animal intestine.

Research progress in toxicological effects and mechanism of aflatoxin B1 toxin

Fungal contamination of animal feed can severely affect the health of farm animals, and result in considerable economic losses. Certain filamentous fungi or molds produce toxic secondary metabolites known as mycotoxins, of which aflatoxins (AFTs) are considered the most critical dietary risk factor for both humans and animals. AFTs are ubiquitous in the environment, soil, and food crops, and aflatoxin B₁(AFB₁) has been identified by the World Health Organization (WHO) as one of the most potent natural group 1A carcinogen. We reviewed the literature on the toxic effects of AFB₁ in humans and animals along with its toxicokinetic properties. The damage induced by AFB₁ in cells and tissues is mainly achieved through cell cycle arrest and inhibition of cell proliferation, and the induction of apoptosis, oxidative stress, endoplasmic reticulum (ER) stress and autophagy. In addition, numerous coding genes and non-coding RNAs have been identified that regulate AFB₁ toxicity. This review is a summary of the current research on the complexity of AFB₁ toxicity, and provides insights into the molecular mechanisms as well as the phenotypic characteristics.

Nutritional impact of mycotoxins in food animal production and strategies for mitigation

Mycotoxins are toxic secondary metabolites produced by filamentous fungi that are commonly detected as natural contaminants in agricultural commodities worldwide. Mycotoxin exposure can lead to mycotoxicosis in both animals and humans when found in animal feeds and food products, and at lower concentrations can affect animal performance by disrupting nutrient digestion, absorption, metabolism, and animal physiology. Thus, mycotoxin contamination of animal feeds represents a significant issue to the livestock industry and is a health threat to food animals. Since prevention of mycotoxin formation is difficult to undertake to avoid contamination, mitigation strategies are needed. This review explores how the mycotoxins aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A impose nutritional and metabolic effects on food animals and summarizes mitigation strategies to reduce the risk of mycotoxicity.

Functional Characterization and Whole-Genome Analysis of an Aflatoxin-Degrading Rhodococcus pyridinivorans Strain

Simple Summary

The microbiological degradation of AFB₁ has been a promising approach to control AFB₁ contamination. Here, we characterize a Rhodococcus pyridinivorans strain that can efficiently degrade AFB₁. The AFB₁-degrading capacity of this bacterial strain was characterized, and the completed genome was sequenced and analyzed. Further proteomic analyses of this strain identified a total of 723 proteins in an extracellular component that showed the strongest capacity to degrade AFB₁ (degradation rate 83.7%). Multiple potential AFB₁-degrading enzymes, and enzymes that are reported to respond to AFB₁ treatment, have been identified accordingly. These findings provide a genomic, proteomic, and experimental approach for characterizing an efficient AFB₁-degrading bacterial strain with great potential for use in the remediation of AFB₁ contamination.

Abstract

Aflatoxin B₁ (AFB₁) is one of the most toxic, naturally occurring carcinogen compounds and is produced by specific strains of fungi. Crop contamination with AFB₁ can cause huge economic losses and serious health problems. Many studies have examined the microbiological degradation of AFB₁, especially the use of efficient AFB₁-degrading microorganisms, to control AFB₁ contamination. Here, we reported the identification of a new Rhodococcus pyridinivorans strain (4-4) that can efficiently degrade AFB₁ (degradation rate 84.9%). The extracellular component of this strain showed the strongest capacity to degrade AFB₁ (degradation rate 83.7%). The effects of proteinase K, SDS, temperature, pH, incubation time, and AFB₁ concentration on the AFB₁ degradation ability of the extracellular component were investigated. We sequenced the complete genome of this strain, encoding 5246 protein-coding genes and 169 RNA genes on a circular chromosome and two plasmids. Comparative genomic analysis revealed high homology with other Rhodococcus strains with high AFB₁-degradation ability. Further proteomic analyses of this strain identified a total of 723 proteins in the extracellular component, including multiple potential AFB₁-degrading enzymes, along with enzymes that are reported to response to AFB₁ treatment. Overall, the results demonstrate that R. pyridinivorans 4-4 would be an excellent candidate for the biodegradation and detoxification of AFB₁ contamination.

Mycotoxins binder supplementation alleviates aflatoxin B1 toxic effects on the immune response and intestinal barrier function in broilers

This experiment was conducted to evaluate whether a commercial mycotoxins-binder, XL, could effectively attenuate the negative effects of Aflatoxin B₁ (AFB₁) on growth performance, immunological function, and intestinal health in birds. Two hundred forty 1-day-old Arbor Acres broiler chickens were randomly divided into 4 treatments using a 2 × 2 factorial randomized design with 2 levels of dietary mycotoxins binder (0 or 2g /kg) and 2 AFB₁ supplemented levels (0 or 200 μg/kg) from 0 to 42 d. Results showed that AFB₁ exposure impaired growth performance by decreasing BWG in 1–21 d and 1–42 d, decreasing FI in 1–21 d, increasing FCR in 1–21 d and 1–42 d (P < 0.05). Broilers fed AFB₁- contaminated diet impaired the immune function, as evident by decreasing IgA contents, Newcastle disease antibody titers in serum, and sIgA contents of jejunal mucosa at 21 d (P < 0.05). On the other hand, AFB₁ challenge significantly increased the gene expression of proinflammatory factors in spleen at 21 d and liver at 42 d, and significantly decreased claudin-1 expression at 42 d and occludin expression at 21 d, and increased claudin-2 at 21 d in jejunum of broiler chickens (P < 0.05) compared to the basal diet group. Dietary XL supplementation significantly decreased the gene expression of IL-6 in spleen at 21 d and IL-1β in liver at 42 d, cytochrome P450 3A4 (CYP3A4) expression in liver at 21 d of broilers (P < 0.05) compared with the nonsupplemented birds, regardless of AFB₁ challenged or not. Inclusion of 2 g/kg XL increased serum ALB at 42 d, IgM and IgA at 42 d, Newcastle disease antibody titer level at 35 d (P < 0.05). Dietary XL addition enhanced intestinal barrier function by increasing the expression of claudin-1 at 21 d and Occludin at 42 d (P < 0.05) in jejunum. Conclusively, 2 g/kg mycotoxins-binder can relieve the toxic effect of AFB₁ on broilers.

Effects of Dietary Ferulic Acid on the Intestinal Microbiota and the Associated Changes on the Growth Performance, Serum Cytokine Profile, and Intestinal Morphology in Ducks

The present study investigated the effects of ferulic acid (FA) on the growth performance, serum cytokine profile, intestinal morphology, and intestinal microbiota in ducks at the growing stage. 300 female Linwu ducks at 28 days of age with similar body weights were randomly divided into five groups. Each group contained six replicates of 10 birds. The dietary treatments were corn-soybean-based diet supplemented with FA at the concentrations of 0 (control), 100, 200, 400, and 800 mg/kg diet. The results demonstrated that dietary FA at the levels of 200, 400, and 800 mg/kg increased the average daily gain (P = 0.01), 400 and 800 mg/kg FA increased the final body weight (P = 0.02), 100, 200, and 800 mg/kg FA increased the serum glutathione (P = 0.01), and 100, 400, and 800 mg/kg FA increased the glutathione peroxidase activities in birds (P < 0.01). Additionally, 200, 400, and 800 mg/kg dietary FA lowered the serum levels of interleukin-2 (P = 0.02) and interleukin-6 (P = 0.04). Moreover, the morphometric study of the intestines indicated that 400 mg/kg FA decreased the crypt depth in jejunum (P = 0.01) and caecum (P = 0.04), and increased the ratio of villus height to crypt depth in jejunum (P = 0.02). Significant linear and/or quadratic relationships were found between FA concentration and the measured parameters. 16S rRNA sequencing revealed that dietary FA increased the populations of genera Faecalibacterium, Paludicola, RF39, and Faecalicoccus in the cecum (P < 0.05), whereas decreased the populations of Anaerofilum and UCG-002 (P < 0.05). The Spearman correlation analysis indicated that phylum Proteobacteria were negatively, but order Oscillospirales, and family Ruminococcaceae were positively related to the parameters of the growth performance. Phylum Bacteroidetes, class Negativicutes and family Rikenellaceae were negatively associated with the parameters of the antioxidative capability. And phylum Cyanobacteria, Elusimicrobia, and Bacteroidetes, class Bacilli, family Rikenellaceae, and genus Prevotella were positively associated with the parameters of the immunological capability. Thus, it was concluded that the supplementations of 400 mg/kg FA in diet was able to improve the growth performance, antioxidative and immunological capabilities, intestinal morphology, and modulated the gut microbial construction of Linwu ducks at the growing stage.

Evaluation of the protective effect of lycopene on growth performance, intestinal morphology, and digestive enzyme activities of aflatoxinB1 challenged broilers

The current study was conducted to investigate the protective efficiency of dietary lycopene (LYC) supplementation on growth performance, intestinal morphology, and digestive enzyme activities aflatoxinB₁ (AFB₁ ) challenged broilers. A total of 240 days old Arber across male broiler chicks were randomly allocated in five treatments and six replicates (eight birds per replicate); feed and water were provided ad libitum during the 42 days experiment. The treatment diets were as follows: (i) Basal diet (control), (ii) Basal diet + 100 µg/kg AFB₁ contaminated diet, (iii) Basal diet + 100 µg/kg AFB₁  + 100 mg/kg LYC1, (iv) Basal diet + 100 µg/kg AFB₁  + 200 mg/kg LYC2, and (v) Basal diet + 100 µg/kg AFB₁  + 400 mg/kg LYC3. The results showed that the addition of LYC to AFB₁ contaminated broiler diets significantly increased (p < .05) average daily gain (ADG) and decreased feed conversion ratio (FCR) compared to the AFB₁ diet. AFB₁ diet decreased the intestinal villus height (VH) and crypt depth ratio (VCR) while increasing the crypt depth (CD). However, dietary LYC supplemented diets relieved the intestinal morphological alterations. Dietary LYC supplementation (200 and 400 mg/kg) significantly improved (p < .05) intestinal digestive enzyme amylase and lipase activities with AFB₁ contaminated diet. These findings suggested that LYC is a promising feed supplement in the broiler industry, alleviating the harmful effects of AFB₁ .

Aflatoxin B1 and Aflatoxin M1 Induce Compromised Intestinal Integrity through Clathrin-Mediated Endocytosis

With the growing diversity and complexity of diet, humans are at risk of simultaneous exposure to aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1), which are well-known contaminants in dairy and other agricultural products worldwide. The intestine represents the first barrier against external contaminants; however, evidence about the combined effect of AFB1 and AFM1 on intestinal integrity is lacking. In vivo, the serum biochemical parameters related to intestinal barrier function, ratio of villus height/crypt depth, and distribution pattern of claudin-1 and zonula occluden-1 were significantly affected in mice exposed to 0.3 mg/kg b.w. AFB1 and 3.0 mg/kg b.w. AFM1. In vitro results on differentiated Caco-2 cells showed that individual and combined AFB1 (0.5 and 4 μg/mL) and AFM1 (0.5 and 4 μg/mL) decreased cell viability and trans-epithelial electrical resistance values as well as increased paracellular permeability of fluorescein isothiocyanate-dextran in a dose-dependent manner. Furthermore, AFM1 aggravated AFB1-induced compromised intestinal barrier, as demonstrated by the down-regulation of tight junction proteins and their redistribution, particularly internalization. Adding the inhibitor chlorpromazine illustrated that clathrin-mediated endocytosis partially contributed to the compromised intestinal integrity. Synergistic and additive effects were the predominant interactions, suggesting that these toxins are likely to have negative effects on human health.

Effects of Chronic Exposure to Low Levels of Dietary Aflatoxin B1 on Growth Performance, Apparent Total Tract Digestibility and Intestinal Health in Pigs

This study aimed to investigate the effects of chronic exposure to low levels of dietary aflatoxin B1 (AFB1) on growth performance, apparent total tract digestibility and intestinal health in pigs. In a 102-day experiment, fourteen barrows (Duroc×Landrace×Yorkshire, initial BW = 38.21 ± 0.45 kg) were randomly divided into control (CON, basal diet) and AFB1 groups (the basal diet supplemented with 280 μg/kg AFB1). Results revealed that the AFB1 exposure decreased the final BW, ADFI and ADG in pigs (p < 0.10). AFB1 exposure also decreased the apparent total tract digestibility of dry mater and gross energy at 50 to 75 kg and 105 to 135 kg stages, and decreased the apparent total tract digestibility of ether extract at 75 to 105 kg stage (p < 0.05). Meanwhile, AFB1 exposure increased serum diamine oxidase activity and reduced the mRNA abundance of sodium-glucose cotransporter 1, solute carrier family 7 member 1 and zonula occluden-1 in the jejunal mucosa (p < 0.05). Furthermore, AFB1 exposure decreased superoxide dismutase activity (p < 0.05) and increased 8-hydroxy-2'-deoxyguanosine content (p < 0.10) in jejunal mucosa. AFB1 exposure also increased tumor necrosis factor-α, interleukin-1β and transforming growth factor-β mRNA abundance in jejunal mucosa and upregulated Escherichia coli population in colon (p < 0.05). The data indicated that chronic exposure to low levels of dietary AFB1 suppressed growth performance, reduced the apparent total tract digestibility and damaged intestinal barrier integrity in pigs, which could be associated with the decreased intestinal antioxidant capacity and the increased pro-inflammatory cytokine production.

The Compromised Intestinal Barrier Induced by Mycotoxins

Mycotoxins are fungal metabolites that occur in human foods and animal feeds, potentially threatening human and animal health. The intestine is considered as the first barrier against these external contaminants, and it consists of interconnected physical, chemical, immunological, and microbial barriers. In this context, based on in vitro, ex vivo, and in vivo models, we summarize the literature for compromised intestinal barrier issues caused by various mycotoxins, and we reviewed events related to disrupted intestinal integrity (physical barrier), thinned mucus layer (chemical barrier), imbalanced inflammatory factors (immunological barrier), and dysfunctional bacterial homeostasis (microbial barrier). We also provide important information on deoxynivalenol, a leading mycotoxin implicated in intestinal dysfunction, and other adverse intestinal effects induced by other mycotoxins, including aflatoxins and ochratoxin A. In addition, intestinal perturbations caused by mycotoxins may also contribute to the development of mycotoxicosis, including human chronic intestinal inflammatory diseases. Therefore, we provide a clear understanding of compromised intestinal barrier induced by mycotoxins, with a view to potentially develop innovative strategies to prevent and treat mycotoxicosis. In addition, because of increased combinatorial interactions between mycotoxins, we explore the interactive effects of multiple mycotoxins in this review.

Paternal weight of ducks may have an influence on offspring' small intestinal function and cecal microorganisms

Background

In animals, many factors affect the small intestinal function and cecal microorganisms, including body weight and genetic background. However, whether paternal weight impacts the small intestinal function and cecal microorganisms remains unknown to date. The current study used Nonghua sheldrake to estimate the effect of paternal weight on the intestine of the offspring by evaluating differences in small intestinal morphology, digestive enzyme activity, and cecal microorganisms between the offspring of male parents with high body weight (group H) and that of male parents with low body weight (group L).

Results

The results of the analysis of small intestinal morphology showed that the villus height of the jejunum of group H ducks was higher than that of group L ducks, and the difference was significant for ducks at 10 weeks of age. Moreover, the villus height/crypt depth of the duodenum in group H significantly exceeded that of group L at a duck age of 2 weeks. The amylase activity in the jejunum content of group H exceeded that of group L at 5 and 10 weeks of age. Furthermore, the proportion of the Firmicutes to Bacteroidetes was significantly higher in group H (duck age of 2 weeks). Among the genera with a relative abundance exceeding 1%, the relative abundances of genera Desulfovibrio, Megamonas, Alistipes, Faecalibacterium, and Streptococcus observed in group H were significantly different between group H and group L.

Conclusions

For the first time, this study identifies the effect of paternal weight on offspring small intestinal function and cecal microorganisms. Consequently, this lays a foundation for further research on the relationship between male parents and offspring intestinal function.

Effects of residual superdoses of phytase on growth performance, tibia mineralization, and relative organ weight in ducks fed phosphorus-deficient diets

This study was conducted to determine the effects of residual superdoses of phytase on growth performance, tibia mineralization, and relative organ weight in ducks fed phosphorus-deficient diets. In Exp. 1, 4 kinds of commercial phytase were used to determine retention rate of phyatse with the phytase C being the highest via both high water-bath temperature (90%) and pelleting (50%), followed by phytase A, B, and D. In Exp. 2, a total of 560 male ducks were blocked based on body weight, and then allocated randomly to 7 treatments (5 replicates with 16 birds per replicate). Treatments included a maize-soybean meal-based diet with recommended calcium and 4.0 g non-phytate phosphorus (nPP)/kg starter diet or 3.8 g nPP/kg grower diet (positive control; PC), an nPP-deficient diet with 1.3 g nPP/kg starter diet or 1.1 g nPP/kg grower diet (negative control; NC), NC diets with increasing levels of residual phytase C (500, 1,000, 2,000, 3,000, and 4,000 units/kg feed) after pelleting. Birds fed NC diets had lower (P < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) throughout the experiment compared with those fed PC diet. Supplementing NC diet with increasing residual superdoses of phytase improved (P < 0.05) ADG and ADFI quadratically in the entire experiment, while reduced feed-to-gain ratio (P < 0.05) quadratically during day 0 to 14. On day 14 and 35, birds fed NC diet had lower (P < 0.05) tibia length, weight, ash, calcium, phosphorus, and manganese contents than those fed PC diet. Increasing residual superdoses of phytase in NC diet increased (P < 0.05) tibia weight and ash, calcium, phosphorus contents quadratically on day 14 and 35. NC treatment increased (P < 0.05) the duodenum, jejunum, ileum, and cecum index compared with other treatments on day 14 and 35. Taken together, feeding increasing residual superdoses of phytase could counteract or exceed the negative effects of NC diet on growth performance, tibia mineralization, and relative organ weight in ducks.

Effects of stale maize on growth performance, immunity, intestinal morphology and antioxidant capacity in broilers

OBJECTIVE

This study was conducted to determine the effects of stale maize on growth performance, immunity, intestinal morphology, and antioxidant capacity in broilers.

METHODS

A total of 800 one-day-old male Arbor Acres broilers (45.4±0.5 g) were blocked based on body weight, and then allocated randomly to 2 treatments with 20 cages per treatment and 20 broilers per cage in this 6-week experiment. Dietary treatments included a basal diet and diets with 100% of control maize replaced by stale maize.

RESULTS

The content of fat acidity value was higher (p<0.05) while the starch, activities of catalase and peroxidase were lower (p<0.05) than the control maize. Feeding stale maize diets reduced (p<0.05) average daily feed intake (ADFI) throughout the experiment, feed conversion ratio (FCR) during d 0 to 21 and the whole experiment as well as relative weight of liver, spleen, bursa of Fabricius and thymus (p<0.05) on d 21. Feeding stale maize diets decreased jejunum villus height (VH) and VH/crypt depth (CD) (p<0.05) on d 21 and 42 as well as ileum VH/CD on d 42. The levels of immunoglobulin G, acid α-naphthylacetate esterase positive ratios and lymphocyte proliferation on d 21 and 42 as well as lysozyme activity and avian influenza antibody H5N1 titer on d 21 decreased (p<0.05) by the stale maize. Feeding stale maize diets reduced (p<0.05) serum interferon-γ, tumor necrosis factor-α, interleukin-2 on d 21 and interleukin-6 on d 21 and 42. Broilers fed stale maize diets had lower levels of (p<0.05) total antioxidative capacity on d 42, superoxide dismutase and glutathione peroxidase on d 21 and 42, but higher (p<0.05) levels of malondialdehyde on d 21 and 42.

CONCLUSION

Feeding 100% stale maize decreased ADFI and FCR, caused adverse effects on immunity and antioxidant function and altered intestinal morphology in broilers.

Harmful Effects and Control Strategies of Aflatoxin B₁ Produced by Aspergillus flavus and Aspergillus parasiticus Strains on Poultry: Review

The presence of aflatoxin B₁ (AFB₁) in poultry diets decreases the hatchability, hatchling weight, growth rate, meat and egg production, meat and egg quality, vaccination efficiency, as well as impairing the feed conversion ratio and increasing the susceptibility of birds to disease and mortality. AFB₁ is transferred from poultry feed to eggs, meat, and other edible parts, representing a threat to the health of consumers because AFB₁ is carcinogenic and implicated in human liver cancer. This review considers how AFB₁ produced by Aspergillus flavus and Aspergillus parasiticus strains can affect the immune system, antioxidant defense system, digestive system, and reproductive system in poultry, as well as its effects on productivity and reproductive performance. Nutritional factors can offset the effects of AFB₁ in poultry and, thus, it is necessary to identify and select suitable additives to address the problems caused by AFB₁ in poultry.

Histopathological Injuries, Ultrastructural Changes, and Depressed TLR Expression in the Small Intestine of Broiler Chickens with Aflatoxin B₁

To explore AFB₁-induced damage of the small intestine, the changes in structure and expression of TLRs (Toll-like Receptors) in the small intestine of chickens were systematically investigated. Ninety healthy neonatal Cobb chickens were randomized into a control group (0 mg/kg AFB₁) and an AFB₁ group (0.6 mg/kg AFB₁). The crypt depth of the small intestine in the AFB₁ group was significantly increased in comparison to the control chickens, while the villus height and area were evidently decreased, as well as the villus:crypt ratio and epithelial thickness. The histopathological observations showed that the villi of the small intestine exposed to AFB₁ were obviously shedding. Based on ultrastructural observation, the absorptive cells of small intestine in the AFB₁ group exhibited fewer microvilli, mitochondrial vacuolation and the disappearance of mitochondrial cristae, and junctional complexes as well as terminal web. Moreover, the number of goblet cells in the small intestine in the AFB₁ group significantly decreased. Also, AFB₁ evidently decreased the mRNA expression of TLR2-2, TLR4, and TLR7 in the small intestine. Taken together, our study indicated that dietary 0.6 mg/kg AFB₁ could induce histopathological injuries and ultrastructural changes, and depress levels of TLR mRNA in the chicken small intestine.

Effects of feeding corn naturally contaminated with aflatoxin on growth performance, apparent ileal digestibility, serum hormones levels and gene expression of Na+, K+-ATPase in ducklings

Objective

A 14-d trial was conducted to determine the effects of feeding corn naturally contaminated with aflatoxin B₁ (AFB₁) on growth performance, apparent ileal digestibility, serum hormones levels and gene expression of Na⁺, K⁺-ATPase in ducklings.

Methods

A total of 704 ducklings were blocked on the basis of sex and body weight (BW), and then allocated randomly to one of the following two treatments: i) CON, basal diet and ii) AFB₁, diets with 100% of normal corn replaced with AFB₁ contaminated corn. There were 22 pens per treatment and 16 birds per pen. The concentration of AFB₁ was 195.4 and 124.35 μg/kg in the contaminated corn and AFB₁ diet, respectively.

Results

The AFB₁ decreased average daily gain, average daily feed intake, d 7 BW, final BW in the whole trial, and feed conversion ratio (FCR) during d 8 to 14 and d 1 to 14 by 10% to 47% (p<0.05), while FCR during d 1 to 7 was increased (p<0.05). AFB₁ did not affect mortality to 7 d of age, and then increased to 5.8% from 8 to 14 d of age (p<0.01). Apparent ileal gross energy digestibility was reduced by AFB₁, whereas apparent ileal digestibility of dry matter, nitrogen, and amino acid was improved (p<0.01). Feeding AFB₁ diets increased serum concentration of leptin and insulin-like growth factors-1 (IGF-1) (p<0.05), but had no effect on neuropeptide Y, ghrelin, cholecystokinin-8 or insulin (p>0.05). Dietary treatments did not influence relative expression of jejunal Na⁺, K⁺-ATPase gene (p>0.05).

Conclusion

Taken together, feeding corn naturally contaminated with AFB₁ reduced growth performance, improved apparent ileal digestibility, and affected serum leptin and IGF-1 in ducklings from d 1 to 14.