Histological alterations of intestinal villi in chickens fed dried Bacillus subtilis var. natto

Effects of zinc dosage and particle size on gut morphology, tight junctions and TNF-α expression in broiler breeder hens

This study was performed to evaluate the effects of different amounts and particle size of zinc oxide (ZnO) on villus height (VH), villus width (VW), crypt depth (CD) and VH to CD ratio (VH: CD), and expression of zonula occludens-1 (ZO-1), occludin (OC) and tumour necrosis factor-α (TNF-α) in broiler breeders. A total of 350 (Ross 308) broiler breeder hens of 54 weeks randomly assigned to seven treatments, included control basal diet (C) without added Zn, C+ 100, and 130 mg Zn per kg of diet from Large (L) (100-1000 nm) and Small (S) (<100 nm) particle size ZnO (LZnO100 and 130; SZnO100 and 130), C and SZnO100 challenged with lipopolysaccharide (C+LPS and SZnO100+LPS). Each diet was fed to five replicates consisting of ten birds each. The middle part of the duodenum, jejunum and ileum was used for morphological assessments. To assess the gene expression of ZO-1, OC and TNF-α in the jejunum samples were excised. Results showed that the supplementing 130 ppm SZnO increased VH:CD in the duodenum (p < 0.05). VW in the duodenum and all the evaluated morphometric indices in jejunum and ileum were not affected by the dietary treatment (p > 0.05). ZO-1 mRNA abundance in C+LPS group compared to SZnO100+LPS group was significantly decreased and increased by LPS and SZnO100 respectively. The SZnO-100 increased OC gene expression in compare to C+LPS group. The expression of TNF-α in C+LPS treatment was higher than other groups (p < 0.05). The lowest and the highest litter moisture and foot-pad dermatitis (FPD) were observed in LZnO-130 and C treatments respectively (p < 0.05). Improving the physical properties of ZnO affect on VH:CD. Broiler breeder diet with ZnO enhance ZO-1, OC and mitigate TNF-α gene expression in jejunum maintenance of gut health in broiler breeders.

Microbial Composition in the Duodenum and Ileum of Yellow Broilers With High and Low Feed Efficiency

The composition of the gut microbiome plays important roles in digestion, nutrient absorption, and health. Here, we analyzed the microbial composition in the duodenum and ileum of yellow broilers. Chickens were grouped based on feed efficiency (high feed efficiency [HFE] and low feed efficiency [LFE] groups; n = 22 each). Microbial samples from the duodenum and ileum were collected, and 16S rRNA sequencing of the V3–V4 region was performed. The dominant bacteria in the duodenum were from the phyla Firmicutes and Cyanobacteria and the genera Lactobacillus, Faecalibacterium, and Ruminococcus. In the ileum, the phyla Firmicutes and Proteobacteria and the genera Lactobacillus, SMB53 and Enterococcus were predominant. Alpha diversity analysis showed that the microbiota diversity was significantly higher in the duodenum than in the ileum. The structure of the ileal microbiota was similar between groups, and the species richness of the microbiota in the HFE group was significantly higher than that in the LFE group. In the HFE and LFE groups, Firmicutes and Cyanobacteria were negatively correlated, and Lactobacillus had medium to high negative correlations with most other genera. Functional prediction analysis showed that the gluconeogenesis I pathway was the most abundant differential metabolic pathway and was significantly altered in the LFE group. Moreover, although the microbial community structures were similar in the duodenum and ileum, the diversity of the microbial community was significantly higher in the duodenum than in the ileum. Pearson correlation analysis revealed that the phylum Chloroflexi and genera Acinetobacter, Pseudomonas, Bacillus and Neisseria were with coefficients <−0.3 or >0.3. In the ileum, Ruminococcus may be associated with HFE whereas Faecalibacterium may be associated with LFE. These findings may provide valuable foundations for future research on composition and diversity of intestinal microbes and provide insights into the roles of intestinal microbes in improving feed efficiency and the industrial economic benefits of yellow broilers.

Effect of Selenium Sources on Laying Performance, Egg Quality Characteristics, Intestinal Morphology, Microbial Population and Digesta Volatile Fatty Acids in Laying Hens

The use of toxic and less bioavailable inorganic selenium can now be supplemented with an alternative organic source from bacterial species in nutrition for human and animal benefit. This study investigated the effects of selenium sources on laying performance, egg quality characteristics, intestinal morphology, caecum microbial population, and digesta volatile fatty acids in laying hens. One hundred and forty-four Lohman Brown Classic laying hens, at 23 weeks of age, were divided into four experimental groups (36 hens in each), differing in form of Se supplementation: no Se supplementation (Con), 0.3 mg/kg of inorganic Se in the form of sodium selenite (Na2SeO3), 0.3 mg/kg of organic Se from selenium yeast (Se-Yeast), and 0.3 mg/kg of organic Se from Stenotrophomonas maltophilia (bacterial organic Se, ADS18). The results showed that different dietary Se sources significantly affected laying rate, average egg weight, daily egg mass, feed conversion ratio (FCR), and live bodyweight (LBW) (p < 0.05). However, average daily feed intake and shell-less and broken eggs were unaffected (p > 0.05) among the treatment groups. The findings revealed that selenium sources had no (p > 0.05) effect on egg quality (external and internal) parameters. However, eggshell breaking strength and Haugh unit were significantly (p < 0.05) improved with organic (ADS18 or Se-yeast) Se-fed hens compared to the control group. In addition, egg yolk and breast tissue Se concentrations were higher (p < 0.05) in the dietary Se supplemented group compared to the control. Intestinal histomorphology revealed that hens fed ADS18 or Se-Yeast groups had significantly (p < 0.05) higher villi height in the duodenum and jejunum compared to those fed Na2SeO3 or a basal diet. However, when compared to organic Se fed (ADS18 or Se-Yeast) hens, the ileum villus height was higher (p < 0.05) in the basal diet group; with the lowest in the SS among the treatment groups. A significant increase (p < 0.05) of Lactobacilli spp. and Bifidobacteria spp., and a decrease of Escherichia coli and Salmonella spp. population were observed in the organic (ADS18 or Se-yeast) compared to inorganic supplemented and control hens. The individual digesta volatile fatty acid (VFA) was significantly different, but with no total VFA differences. Thus, bacterial selenoprotein or Se-yeast improved the performance index, egg quality characteristics, egg yolk and tissue Se contents, and intestinal villus height in laying hens. Moreover, caecum beneficial microbes increased with a decrease in the harmful microbe population and affected individual cecal volatile fatty acids without affecting the total VFA of the laying hens digesta.

Varying combinations of Lactobacillus species: impact on laying hens' performance, nitrogenous compounds in manure, serum profile, and uric acid in the liver

This study was conducted to evaluate the effects of various combinations of Lactobacillus species (L. rhamnosus, L. paracasei, and L. plantarum) on closely associated variables of production of laying hens, nitrogenous compounds in manure, the serum concentration of specific chemicals, and liver uric acid (UA) concentrations at peak lay. White Leghorns W-36 (32-week-old) were randomly assigned to five treatments for 8 weeks. Treatments were T1, the Control, a commercial feed; T2, the Control + L. paracasei + L. plantarum; T3, the Control + L. paracasei + L. rhamnosus; T4, the Control + L. plantarum + L. rhamnosus and T5, the Control + L. paracasei + L. plantarum + L. rhamnosus. Each bacterial species was included at 3.33 × 10¹¹cfu/kg feed for a total of 6.66 x 10¹¹ cfu/kg feed for T2–T4 and a total of 1.0 × 10¹² cfu/kg feed for T5. Major effects among combinations of probiotics on production were not noted. The interaction of Probiotics by Week (Probiotics*Time) affected feed intake (P = 0.0007) and feed conversion ratio (FCR, P = 0.0049) due to fluctuation by week. Significant effects of time were also recorded for a gradual increase in body weight (BW, P = 0.0007); lowest and greatest feed intake at weeks 2 and 7, respectively (P < 0.0001); an increase in egg production (P = 0.0007) and maximum FCR at week 7 (P < 0.0001). Ammonia (NH₃) concentration, ammonium nitrogen (NH₄–N), total Kjeldahl nitrogen (TKN), and total nitrogen remained unaffected at P < 0.05. Although there were fluctuations, a trend emerged for the reduction of TKN. Combinations of probiotics did not affect NH₃, UA, total protein (TP), albumin (ALB), creatine kinase (CK), and UA in the liver. Temporal (Time as a fixed effect) effects were noted for all nitrogenous compounds present in manure. For ammonia, temporal effects were significant due to fluctuation over time. Week 0 had the lowest value followed by weeks 4 and 8. Week 6 had the greatest value. For ammonium nitrogen, week 8 had the lowest value followed by week 0 and 4 with the next highest value. Week 6 had the greatest value. For TKN, week 4 had the lowest value followed by weeks 6 and 8. Week 0 had the greatest value. For TN, weeks 4, 6, and 8 had similar and lowest values followed by week 0 having the greatest value. However, an overall reduction in NH₄-N, TKN, and TN was noted. Fluctuations in NH₃ (P = 0.0033) and CK (P = 0.0085) were noted for Time. There was also a trend (P = 0.0706) for the increase of UA in serum. Two or more species of probiotics with yeast should be investigated. If the combination is applicable for increasing production measurements and reducing nitrogenous and serum compounds, the most appropriate time to feed the probiotics from day 1 to the end of production should be investigated.

The Use of Probiotics in the Reduction of Campylobacter spp. Prevalence in Poultry

Campylobacter spp. are widely distributed microorganisms, many of which are commensals of gastrointestinal tract in multiple animal species, including poultry. Most commonly detected are C. jejuni and C. coli. Although infections are usually asymptomatic in poultry, poultry meat and products represent main sources of infection with these bacteria to humans. According to recent EFSA report, campylobacteriosis is the most commonly reported zoonotic disease. In 2018, EFSA Panel on Biological Hazards indicated that use of feed and water additives is the second most likely strategy that can be successful in minimizing Campylobacter spp. colonization rate in broiler chickens. One of those feed and water additives are probiotics. From numerous research papers it can be concluded that probiotics exhibit plenty of mechanisms of anti-Campylobacter activity, which were evaluated under in vitro conditions. These results, to some extent, can explain the efficacy of probiotics in in vivo studies, although different outcome can be observed under these two laboratory conditions. Probiotics are capable of reducing Campylobacter spp. population count in poultry gastrointestinal tract and they can reduce carcass contamination. Potential modes of anti-Campylobacter activity of probiotics, results of in vivo studies and studies performed at a farm level are widely discussed in the paper.

Growth performance, carcass traits and gut health of broiler chickens fed diets incorporated with single cell protein

Objective

This study was conducted to evaluate single cell protein (SCP), produced from Methylococcus species, as a protein source on the growth performance, carcass traits and gut health of broiler chickens.

Methods

Ten iso-nitrogenous and iso-caloric diets containing 0 (Control), 2.5%, 5%, 7.5%, and 10% SCP replacing either soybean meal (T₁ to T₅) or fish meal (T₆ to T₁₀) were formulated. Each diet prepared for starter (0 to 14 days), grower (15 to 21 days), and finisher (22 to 42 days) phases was offered to four replicates of 10 chicks each (n = 400). Growth performance at different phases and carcass characteristics and intestinal morphology on 42nd day of trial were measured.

Results

Body weight gain in groups fed 2.5% and 5% SCP diets were comparable to control during different phases and cumulatively, however lower (p<0.01) in 7.5% and 10% SCP diets. Feed conversion ratio was better (p<0.01) in 2.5% and 5% SCP diets. Dressing percentage, abdominal fat percentage and meat:bone ratio were not affected (p>0.05) by SCP inclusion in the diets. However, breast percentage was higher (p<0.01) in 2.5% and 5% SCP groups and thigh percentage higher in 7.5% and 10% SCP groups. Total microbial count in duodenum, jejunum and ileum were not affected (p>0.05) by SCP inclusion up to 10% in diets. Duodenal villi length and crypt depth were highest (p<0.01) in group fed 5% SCP diets and lowest in group fed 10% SCP diets. Jejunal villi length and crypt depth as well as ileal villi length were lowest (p<0.01) in group fed 10% SCP diets. Body weight gain, feed consumption, feed conversion ratio and gut health were better (p<0.01) in broilers fed fish meal based diets compared to soybean meal based diets.

Conclusion

It was concluded that inclusion of SCP up to 5% replacing soybean meal in broiler diets is beneficial in improving growth rate, breast yield and gut health status.

Effect of Walnut Meal Peptides on Hyperlipidemia and Hepatic Lipid Metabolism in Rats Fed a High-Fat Diet

As a natural active substance that can effectively improve blood lipid balance in the body, hypolipidemic active peptides have attracted the attention of scholars. In this study, the effect of walnut meal peptides (WMP) on lipid metabolism was investigated in rats fed a high-fat diet (HFD). The experimental results show that feeding walnut meal peptides counteracted the high-fat diet-induced increase in body, liver and epididymal fat weight, and reduce the serum concentrations of total cholesterol, triglycerides, and LDL-cholesterol and hepatic cholesterol and triglyceride content. Walnut meal peptides also resulted in increased HDL-cholesterol while reducing the atherosclerosis index (AI). Additionally, the stained pathological sections of the liver showed that the walnut meal peptides reduced hepatic steatosis and damage caused by HFD. Furthermore, walnut meal peptide supplementation was associated with normalization of elevated apolipoprotein (Apo)-B and reduced Apo-A1 induced by the high-fat diet and with favorable changes in the expression of genes related to lipid metabolism (LCAT, CYP7A1, HMGR, FAS). The results indicate that walnut meal peptides can effectively prevent the harmful effects of a high-fat diet on body weight, lipid metabolism and liver fat content in rats, and provide, and provide a reference for the further development of walnut meal functional foods.

Extract of Aloe vera (Aloe barbadensis Miller) Enhances the Growth, Protein Contents, and Gastrosomatic Index (GaSI) of Common Carp Cyprinus carpio

Aquaculture is a growing agribusiness, and large-scale microbial infection frequently leads to considerable economic losses, as there are very few approved drugs available to counteract such a problem. Aloe vera is a natural therapeutic plant with biological activities, for example, antimicrobial, anticancer, mitigating, and immunomodulatory properties. Thus, an experiment was conducted to understand the effects of dietary Aloe vera on survival, growth performance, protein utilization, gastrosomatic index, and gut histomorphological studies in common carp in laboratory conditions. Aloe vera leaves were collected, washed, shade-dried, and homogenized to get a filtrate, which was extracted in ethanol (70%) using the Soxhlet apparatus. The carp with an average weight of 1.73 ± 0.14 g was divided randomly into 5 treatments (control and other 4 treated groups) with the extract of 0.0%, 0.2%, 0.4%, 0.8%, and 1.6% in the diet with 3 replicates and the stocking density was 25 fish per each replicate. Sampling was done on the 30th, 60th, and 90th days, and the results show that percent weight gain, specific growth rate, protein efficiency ratio, and feed conversion efficiency were significantly high in the treated diet compared to the control (0.0%). Gastrosomatic index, condition factors, and gut histology found better performance in common carp group fed 0.4% and 0.8% of Aloe vera after 90 days. In conclusion, it was found that Aloe vera extract between the amount of 0.4% and 0.8% is better for fish growth for common carp.

The Immunostimulatory Effects of Commercial Feed Additives on Growth Performance, Non-specific Immune Response, Antioxidants Assay, and Intestinal Morphometry of Nile tilapia, Oreochromis niloticus

The main objective of the present research was to investigate the impacts of commercial immunostimulants on growth, non-specific immune response, antioxidant enzymes, and intestinal morphometry of Nile tilapia, Oreochromis niloticus. Fish (100 ± 6.5 g) were randomly divided into five groups in triplicates (150 fish in each replicate), stocked in 20 m² of aerated concrete ponds. The fish were fed on a control diet (30.0% crude protein) (control), and four experimental diets supplemented with Yeast Plus^®, Digestarom^®, and Biotronic^® Top³ at 1 kg ton^–1, and Sanolife PRO-F^® at 0.5 kg ton^–1. After the experimental period, the highest significant yield (kg m^–3), mean final weight (g fish^–1), average weight gain (g fish^–1), and specific growth rate (% body weight day^–1), were recorded in fish fed on the diet supplemented by Sanolife PRO-F, followed by Yeast Plus ponds. The lowest yield was recorded in the control group. However, the feed conversion ratio was significantly decreased with Sanolife PRO-F diet. Furthermore, the hematological analysis increased in the following ascending order: Sanolife PRO-F^®; Yeast Plus^®; Biotronic^® Top3 and finally Digestarom^® groups. The lowest concentrations of white blood cells, red blood cells, hematocrite, and hemoglobin (P ≤ 0.05) were observed in the control group. The levels of phagocytic activity and phagocytic index were significantly higher in fish fed with Sanolife PRO-F^® group (P ≤ 0.05). Likewise, serum lysozyme activity was significantly highest in Sanolife PRO-F (0.63 and 0.68 U/mL, after 0.5 min and 3 min, respectively). Levels of total serum proteins, globulin, Immunoglobulin M, catalase, and super oxide dismutase were significantly higher in fish fed with Sanolife PRO-F^® supplement. On the contrary, length measurement of the intestinal villus height/width, absorption area, crypt depth, and goblet cells, were significantly lower in the control group, whereas their highest values was observed in fish fed Sanolife PRO-F (P ≤ 0.05). Consequently, Sanolife PRO-F^® is recommended at a level of 0.5 kg ton^–1, to improve the growth performance, antioxidative capacity, and immune response of Nile tilapia.

Effects of dietary red-osier dogwood (Cornus stolonifera) on growth performance, blood profile, ileal morphology, and oxidative status in weaned pigs challenged with Escherichia coli K88+

A total of 28 piglets weaned at 21 d of age (6.94 ± 0.28 kg of body weight) were assigned to one of four dietary treatments for 14 d: (1) negative control (NC; a corn–wheat–soybean meal diet), (2) positive control [PC; NC + 0.025% antimicrobial growth promoter (AGP)], (3) ROD2 [2% red-osier dogwood (ROD)], and (4) ROD4 (4% ROD). All pigs were orally inoculated with Escherichia coli K88+ on day 8. The pre-planned orthogonal test was performed to compare (1) NC vs. PC and (2) NC vs. ROD. The inclusion of ROD in a nursery diet increased (P < 0.05) superoxide dismutase (SOD) activities and decreased (P < 0.05) malondialdehyde (MDA) concentrations in the serum. Moreover, pigs fed with ROD diets had shallower (P < 0.05) crypt depth and higher (P < 0.05) villus height to crypt depth ratio than those fed the NC diet. Dietary AGP supplementation reduced (P < 0.05) the MDA concentration in the ileum and serum at 24 h after challenge, and improved (P < 0.01) the SOD activities in the serum. In conclusion, the inclusion of ROD in a nursery diet enhanced the antioxidative defense system and intestinal morphology, showing comparable effects with AGP supplementation.

Immunosecurity: immunomodulants enhance immune responses in chickens

The global population has increased with swift urbanization in developing countries, and it is likely to result in a high demand for animal-derived protein-rich foods. Animal farming has been constantly affected by various stressful conditions, which can be categorized into physical, environmental, nutritional, and biological factors. Such conditions could be exacerbated by banning on the use of antibiotics as a growth promoter together with a pandemic situation including, but not limited to, African swine fever, avian influenza, and foot-and-mouth disease. To alleviate these pervasive tension, various immunomodulants have been suggested as alternatives for antibiotics. Various studies have investigated how stressors (i.e., imbalanced nutrition, dysbiosis, and disease) could negatively affect nutritional physiology in chickens. Importantly, the immune system is critical for host protective activity against pathogens, but at the same time excessive immune responses negatively affect its productivity. Yet, comprehensive review articles addressing the impact of such stress factors on the immune system of chickens are scarce. In this review, we categorize these stressors and their effects on the immune system of chickens and attempt to provide immunomodulants which can be a solution to the aforementioned problems facing the chicken industry.

Genomics Analysis of Bacillus megaterium 1259 as a Probiotic and Its Effects on Performance in Lactating Dairy Cows

In this study, we isolated a novel bacterium, Bacillus megaterium 1259 (BM1259), from chicken manure. Whole-genome sequencing analysis showed that the BM1259 complete genome is composed of a 5,043,095 bp circular chromosome and three circular plasmids, and it encodes 5379 coding genes and 182 RNA genes. Among these genes, a series of nitrate assimilation-related genes and pathways were identified, implying a potential role of BM1259 in nitrate metabolism. In addition, 24 lactating Holstein dairy cows were randomly assigned to four groups that were fed a total mixed ration (TMR) diet only (C), a TMR diet supplemented with 5 g/day of BM1259 (T1), a TMR diet supplemented with 10 g/day of BM1259 (T2), or a TMR diet supplemented with 15 g/day of BM1259 (T3). The results showed that supplementing dairy cows with 15 g/day of BM1259 increased 4% fat-corrected milk production. The molar proportion of propionate (C3) was significantly higher in T2 than in C. The C2:C3 ratio of T3 was higher than those of C and T2. No negative effect of BM1259 on blood indicators was detected. This study demonstrates BM1259 can be applied as a potential probiotic to improve nitrogen utilization and milk production in lactating dairy cows.

Influence of sanguinarine-based phytobiotic supplementation on post necrotic enteritis challenge recovery

In the animal production industry, plant-derived antimicrobial phytobiotics are used as an alternative to antibiotics. Here we investigated the role sanguinarine-based phytobiotic in broiler recovery from Necrotic Enteritis (NE) infection. A total of 100 one-day-old broiler chicks (Ross 308) were randomly allocated to four treatments: negative control CTR (no challenge, no phytobiotic supplementation); positive control NE (NE challenged); phytobiotic SG (sanguinarine phytobiotic, 0.12 g/kg); and SG + NE, (sanguinarine phytobiotic, 0.12 g/kg and NE challenge). Sanguinarine-based phytobiotic supplementation caused significant changes between the groups in performance, livability and histological measurements, however, these changes were not significantly different between SG + NE and NE groups. Significant improvement was detected in NE lesion score of the duodenum and ileum of SG + NE birds compared to NE challenged birds at the end of the production cycle at 40 days old, indicating improved post-NE recovery with the addition of phytobiotic. Sanguinarine-based phytobiotic supplementation in NE challenged birds significantly compensated for a NE associated reduction of Firmicutes and an increase in Bacteroidetes. Functional profile of sanguinarine-based phytobiotic supplemented birds microbiota was distinct from CTR functional profile. NE challenge was associated with a significant increase in cecal propionic acid, while sanguinarine-based phytobiotic supplementation resulted in an increase in cecal acetic acid.

Effects of manganese and Bacillus subtilis on the reproductive performance, egg quality, antioxidant capacity, and gut microbiota of breeding geese during laying period

This experiment was conducted to investigate the effects of manganese (Mn) and Bacillus subtilis (BS) on the production performance, egg quality, antioxidant capacity, and gut microbiota of breeding geese during laying period. A total of 120 forty-six-week-old breeding geese (Wulong) were randomly assigned to 1 of 6 treatment diets formulated to supply 10, 20, and 30 mg/kg Mn with 5 × 109 CFU/kg or 2.5 × 109 CFU/kg BS for a 10-wk trial. Results showed that dietary supplementation with 20 and 30 mg/kg Mn could decrease the daily feed intake (DFI) of geese. Moreover, 30 mg/kg Mn significantly increased the laying rate. Besides, although Mn addition had no obvious effect on egg quality, 5 × 109 CFU/kg BS was found to elevate the hatching egg hatching rate and eggshell thickness. For the serum hormones, 30 mg/kg Mn promoted estradiol secretion, while 5 × 109 CFU/kg BS increased the level of follicle-stimulating hormone. Furthermore, 20 and 30 mg/kg Mn and 5 × 109 CFU/kg BS significantly enhanced the total antioxidant capacity by increasing the activity of total superoxide dismutases or decreasing the content of malondialdehyde. Dietary supplementation with 5 × 109 CFU/kg BS also increased the intestinal villus height and upregulated the abundance of Fusobacteria, Fusobacteriaceae, Fusobacterium, and Faecalibacterium in cecal content. In addition, 20 and 30 mg/kg Mn elevated the levels of Bacteroidetes, Bacteroidaceae, Bacteroides, and Ruminococcaceae but decreased Streptococcaceae. Importantly, an interaction effect was observed between Mn and BS on the DFI, egg mass, average egg size, and the abundance of Bacteroides as well as Faecalibacterium. In conclusion, dietary inclusion of Mn and BS could improve the production performance, egg quality, antioxidant capacity, intestinal structure, as well as gut microbiota. Supplementation of 30 mg/kg Mn and 5.0 × 109 CFU/kg BS provided the optimal effect.

Probiotics in poultry feed: A comprehensive review

The use of antibiotics to maintain animal well-being, promote growth and improve efficiency has been practised for more than 50 years. However, as early as the 1950s, researchers identified concern on the development of resistant bacteria for the antibiotics streptomycin and tetracycline used in turkeys and broilers respectively. These findings laid the groundwork for agricultural officials to impose stricter regulatory parameters on the use of antibiotics in poultry feeds. Probiotics are live micro-organisms included in the diet of animals as feed additives or supplements. Commonly known as a direct-fed microbial, probiotics provide beneficial properties to the host, primarily through action in the gastrointestinal tract (GIT) of the animal. Supplementation of probiotics in the diet can improve animal health and performance, through contributions to gut health and nutrient use. For instance, supplementation of probiotics has been demonstrated to benefit farm animals in immune modulation, structural modulation and increased cytokine production, which positively affect the intestinal mucosal lining against pathogens. Bacillus subtilis has been a popular bacterium used within the industry and was shown to improve intestinal villus height. Increasing the villus height and structure of the crypts in the GIT allows for the improvement of nutrient digestion and absorption. Tight junctions maintain important defences against pathogenic bacteria and cellular homeostasis. Heat stress can be a major environmental challenge in the poultry industry. Heat stress causes the bird to fluctuate its internal core temperature beyond their comfort zone. To overcome such challenges, poultry will attempt to balance its heat production and dissipation through behavioural and physiological adaptation mechanisms.

Bacillus subtilis PB6 based probiotic supplementation plays a role in the recovery after the necrotic enteritis challenge

In poultry production, birds are raised under intensive conditions, which can enable rapid spread of infections, with Clostridium perfringens-caused necrotic enteritis (NE) being one of the most devastating for the industry. The current investigation was conducted to evaluate the effectiveness of Bacillus subtilis PB6 probiotic supplementation on bird’s post NE recovery, based on chicken performance, cecal microbiota composition, ileum histomorphometric measurements, and short-chain fatty acid production in the cecum of the birds that were challenged with NE mid-production. Birds were split into four groups, including a negative control, positive control challenged with C. perfringens, group supplemented with B. subtilis probiotic, and NE challenged birds supplemented with B. subtilis probiotic. Following NE challenge birds were allowed to reach the end of production time at 40 days, and samples were collected to estimate if probiotic supplementation resulted in better post-NE recovery. Intestinal lesion score across the duodenum, jejunum, and ileum indicated that at the end of production timeline NE challenged birds supplemented with B. subtilis probiotic had lower intestinal lesion scores compared to NE challenged birds without probiotic supplementation implying improved recovery. Probiotic supplementation improved performance of NE challenged birds only in the post-NE recovery stage. NE challenged birds had a significant increase in cecal propionic acid, which was not observed in NE challenged birds supplemented with B.subtilus. Both B. subtilis supplemented groups (challenged and unchanged) were characterized by a significant rise in cecal acetic and butyric acid. Our results demonstrate that B. subtilis supplementation can assist the birds in dealing with NE outbreak and long term recovery.

Effect of a direct-fed microbial and prebiotic on performance and intestinal histomorophology of turkey poults challenged with Salmonella and Campylobacter

Salmonella and Campylobacter are leading human foodborne pathogens commonly associated with poultry and poultry products, and several methods to control these pathogens have been applied to poultry production. This study was conducted to evaluate the effect of CALSPORIN, (CSP), a direct-fed microbial (DFM), and yeast cell wall (Saccharomyces cervisiae, IMW50, a mannanoligosaccharide (MOS)-based prebiotic, on performance, levels of Salmonella and Campylobacter in the feces, and intestinal histomorphometry in turkey poults. A 21-day battery cage study was conducted using 4 dietary treatments, including: an unsupplemented basal diet (corn and soybean-based) as negative control (NC); basal diet supplemented with 0.05% DFM; basal diet supplemented with 0.05% MOS; and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female Large White turkey poults (n = 336) were randomly distributed in 6 electrically-heated battery cages with 4 treatments and 12 replicates per treatment (7 poults per replicate pen). The first 16 pens were not inoculated with bacteria, while poults in pens 17 to 32 were orally challenged at day 7 with 105 CFU Salmonella Heidelberg and the poults in pens 33 to 48 were orally challenged at day 7 with 105 CFU Campylobacter jejuni. Feed consumption, body weight, and feed conversion ratio were measured weekly and at the end of the experiment. At day 21, fresh fecal samples from each pen were collected for Salmonella and Campylobacter enumeration and ileal tissue samples were collected from 1 bird per pen for histomorphology examination. DFM and MOS supplementation was accompanied with reduced levels of Salmonella shed by the treated birds compared to the control group, and with increased body weight (P ≤ 0.05). The surface area of villi increased in the MOS-supplemented group compared to the control group (P ≤ 0.05). There was a significant difference in V:C ratio between supplemented groups and control group (P ≤ 0.05). Based on these results, there is potential for CALSPORIN and IMW50 to reduce Salmonella shedding in feces, enhance ileal mucosal health, and improve growth performance of turkey poults.

Recent Advances in the Physiology of Spore Formation for Bacillus Probiotic Production

Spore-forming probiotic bacteria have received a wide and constantly increasing scientific and commercial interest. Among them, Bacillus species are the most studied and well-characterized Gram-positive bacteria. The use of bacilli as probiotic products is expanding especially rapidly due to their inherent ability to form endospores with unique survivability and tolerance to extreme environments and to produce a large number of valuable metabolites coupled with their bio-therapeutic potential demonstrating immune stimulation, antimicrobial activities and competitive exclusion. Ease of Bacillus spp. production and stability during processing and storage make them a suitable candidate for commercial manufacture of novel foods or dietary supplements for human and animal feeds for livestock, especially in the poultry and aquaculture industries. Therefore, the development of low-cost and competitive technologies for the production of spore-forming probiotic bacteria through understanding physiological peculiarities and mechanisms determining the growth and spore production by Bacillus spp. became necessary. This review summarizes the recent literature and our own data on the physiology of bacilli growth and spore production in the submerged and solid-state fermentation conditions, focusing on the common characteristics and unique properties of individual bacteria as well as on several approaches providing enhanced spore formation.

Effect of Antimicrobial Peptide Microcin J25 on Growth Performance, Immune Regulation, and Intestinal Microbiota in Broiler Chickens Challenged with Escherichia coli and Salmonella

Simple Summary

Antimicrobial peptides are thought to be ideal candidates, owing to their antimicrobial properties, broad spectrum of activity, and low propensity for development of bacterial resistance. Microcin J25 (MccJ25) is an antimicrobial peptide produced by a fecal strain of Escherichia coli (E. coli) containing 21 Arbor Acres (AA) broilers, and has a strong inhibition on E. coli and Salmonella. This study was performed primarily to evaluate the effects of MccJ25 on growth performance and gut health in broilers challenged with E. coli and Salmonella, as a potential substitute for antibiotics. The results showed that MccJ25 promoted growth performance, improved intestinal morphology, and influenced fecal microbiota composition.

Abstract

The purpose of this study was to investigate the effects of antimicrobial peptide microcin J25 (MccJ25) on growth performance, immune regulation, and intestinal microbiota in broilers. A total of 3120 one-day-old male Arbor Acres (AA) broilers were randomly allocated to five groups (12 replicates, 52 chickens per replicate). The treatments were control, challenge (0 mg/kg MccJ25), different dosages of antimicrobial peptide (AMP) (0.5 and 1mg/kg MccJ25), and antibiotic groups (20 mg/kg colistin sulfate). The MccJ25 groups increased the body weight gain (starter and overall) that was reduced in the challenge group. The overall (day 1 to day 42) feed-to-gain ratio (G:F) was significantly decreased in AMP groups compared with the challenge group. Birds fed AMP had a decreased population of total anaerobic bacteria (day 21 and day 42) and E. coli (day 21 and day 42) in feces, as well as a lower Salmonella infection rate (day 21 and day 42) compared with birds in the challenge group. The villus height of the duodenum, jejunum, and ileum, as well as the villus height/crypt depth of the duodenum and jejunum were greater in AMP groups than birds in the challenge group. Moreover, MccJ25 linearly improved the villus height of the duodenum and jejunum. The addition of MccJ25 decreased the concentration of TNF-α, IL-1β, and IL-6 compared with challenge group. At d 21, MccJ25 linearly reduced the level of IL-6. In conclusion, dietary supplemented MccJ25 effectively improved performance, systematic inflammation, and improved fecal microbiota composition of the broilers.

Effects of a combination of xylanase, amylase and protease, and probiotics on major nutrients including amino acids and non-starch polysaccharides utilization in broilers fed different level of fibers

This study evaluated the effects of a combination of xylanase, amylase, and protease (XAP), with probiotics (3 Bacillus spp.) supplementation on apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients in Cobb 500 broilers from 0 to 21 d. A completely randomized 2 × 4 factorial design (2 levels of fiber; 4 types of supplements) with 8 replicate cages (6 birds/cage) was used. Each low and high-fiber diet contained 500 FTU/kg Buttiauxella sp. phytase and was supplemented with: (a) none (control), (b) XAP (2,000 U xylanase + 200 U amylase + 4,000 U protease/kg diet), (c) probiotics (75,000 CFU/g of Bacillus spp.), or (d) XAP + probiotics. High fiber decreased (P < 0.05) nitrogen-corrected apparent metabolizable energy (AMEn), AID of all amino acids (AA), AID and ATTD of dry matter (DM), crude protein (CP), starch, and gross energy (GE). High fiber increased (P < 0.01) the flow of total non-starch polysaccharides (NSP) in both ileum and total tract. The XAP + probiotics increased (P < 0.01) AMEn as well as AID and ATTD of DM, CP, GE, starch, while alone, XAP yielded similar improvement except for DM compared with control. The supplemental XAP alone improved (P < 0.01) the digestibility of most of the AAs compared with control. Moreover, XAP + probiotics increased (P < 0.05) AID of all AA except arginine and serine compared with control. A fiber × supplements interaction (P < 0.05) was found for AID of histidine and threonine, and their digestibility in high-fiber diet was improved to a level comparable to low-fiber diet by XAP + probiotics. The flow of NSP in XAP group was 5 to 6% lower than in control while NSP flow in XAP + probiotic group was further 4% lower than that of XAP group (P < 0.01). The results infer that the combination of XAP and probiotics can effectively optimize the nutrient digestibility in broilers fed both low and high-fiber diets.

A novel Bacillus based multi-strain probiotic improves growth performance and intestinal properties of Clostridium perfringens challenged broilers

There is a necessity for the implementation of in-feed probiotics in the poultry production industry, following strict regulations around the use of antibiotic growth promoters (AGP). Bacillus spp. are becoming an attractive alternative because of their functionality and stability. This study aims to evaluate the effect of a novel multi-strain Bacillus based probiotic on growth performance and gut health in male Ross 308 broiler chickens challenged with Clostridium perfringens Type A. Broilers on a 4 phase feeding program were fed diets containing either a standard metabolizable energy (ME) (100%) or a reduced ME (98%) level. The test probiotic was compared to an un-supplemented negative control and a commercial benchmark product as positive control over a 35 D feeding trial, using a 2 × 3 factorial experimental design. Chicks were inoculated with a once-off dose of C. perfringens on day 14. Growth performance was measured weekly to calculate body weight (BW), feed intake (FI) and feed conversion ratio (FCR). Villi histomorphology, gut lesions, and liver weight were assessed at day 35. Broilers fed the reduced ME diet with the test probiotic achieved higher final BWs (P = 0.037) and FCR (P = 0.014) than the negative control. Broilers fed the standard ME diet with the test probiotic showed improved (P = 0.001) FCR than the negative control from day 21 onwards. Increased duodenal villi height (P = 0.012) and villi height to crypt depth ratio in the duodenum (P < 0.0001) and jejunum (P = 0.0004) were observed in broilers fed the reduced ME diet containing the test probiotic. Additionally, the test probiotic resulted in significantly reduced relative liver weights in both ME groups. Consequently, the results suggest that the novel multi-strain Bacillus based probiotic enhanced broiler performance and improved gut health and is thus attractive as an alternative to AGP's in broiler production.

Use of Bacillus subtilis PB6 enriched with choline to improve growth performance, immune status, histological parameters and intestinal microbiota of broiler chickens

Context Probiotics used in poultry nutrition may promote the propagation of beneficial bacteria and limit the growth of pathogens, improving the body’s resistance to disease. Aims The aim of the study was to establish the dose and timing of administration of a probiotic preparation containing live cultures of Bacillus subtilis PB6 and choline that would have the most beneficial effect on histological parameters and microbiological status of the intestine, immune status, and growth performance of broiler chickens. Methods In total, 980 one-day-old Ross 308 male chickens, divided into seven groups of 140 (each group with seven replications of 20 individuals), were used in the experiment. The birds were reared until Day 42 of life. In the control group, birds received water without addition of the probiotic preparation. In three continuous treatments, birds received the probiotic preparation in their water at doses of 0.05, 0.1 or 0.25 g/L from Day 1 to Day 42 of rearing. In three periodic treatments, birds received the same doses of the probiotic preparation, but only during Days 1–7, 15–21 and 29–35 of rearing. Key results Addition of the probiotic preparation to the drinking water of broiler chickens increased the total number of aerobic bacteria as well as the length of the intestinal villi and the depth of the crypts. It also reduced the number of fungi and coliform bacteria. In addition, increases were noted in the lysozyme content, the phagocytic index, and the level of immunoglobulin A. Conclusions The probiotic preparation containing B. subtilis and choline administered continuously at a dose of 0.25 g/L in water throughout the rearing period had the most beneficial effect on the composition of the microbiome, and improved the mucous membrane structure of the intestine (increasing villus length and intestinal crypt depth), immunity, and growth performance of the broiler chickens. Implications The use of probiotics in poultry nutrition improves the health of animals and makes breeding more profitable. Administration of this probiotic improves disease resistance, jejunal histological parameters, and intestinal microflora of broiler chickens.

The Effect of Addition of Probiotic Bacteria (Bacillus Subtilis or Enterococcus faecium) or Phytobiotic Containing Cinnamon Oil to Drinking Water on the Health and Performance of Broiler Chickens

The aim of the study was to test whether the use of probiotic bacteria Bacillus subtilis or Enterococcus faecium or a phytobiotic containing cinnamon oil can improve the metabolic parameters, immune status, gut microbiota and histology, and growth performance of broiler chickens. The experiment was carried out on 560 one-day-old male Ross 308 broiler chickens raised until the age of 42 days. The broiler chickens were assigned to 4 experimental groups of 140 birds each (7 replications of 20 individuals each). The control group (Control) did not receive additives. A probiotic preparation containing live bacterial cultures of Enterococcus faecium (EF, in the amount of 0.25 g/l) or Bacillus subtilis (BS, 0.25 g/l) or a phytobiotic preparation containing cinnamon oil (OC, 0.25 ml/l) was administered to the broiler chickens with their drinking water throughout the rearing period. The most important results indicate that the use of BS and OC resulted in: a significant (P≤0.05) increase in the level of ferric reducing ability of plasma (FRAP), high-density cholesterol (HDL) and glutathione (GSH + GSSH) and a significant (P≤0.05) decrease in the level of malondialdehyde (MDA), lipid hydroperoxides (LOOH), total cholesterol (TC), triacylglycerols (TAG), nonesterified fatty acids (NEFA) and interleukin 6 (IL-6), a ratio of heterophils : leukocytes (H:L) and alkaline phosphatase (ALP) activity, alanine aminotransferase (ALT), acidic phosphatase (AC) and creatinine kinase (CK), relative to the C group. In the blood of broiler chickens from the OC treatment, aspartate aminotransferase (AST), lactate dehydrogenase activity and 3-hydroxy-butyrate dehydrogenase (HBDH) significantly (P≤0.05) decreased in relation to the C group, and in broiler chickens from EF and BS treatments there was an increase (P≤0.05) in haemoglobin (Hb) content. Compared with group C, in the broiler chickens’ nutritional content from EF, BS and OC treatments, the total number of coliforms and number of fungi significantly (P≤0.05) dropped and the number of aerobic bacteria increased (P≤0.05) in the length of the villus and the depth of the crypt. It has been found that Bacillus subtilis, Enterococcus faecium and phytobiotic containing cinnamon oil can improve the microbiological and histological appearance of broiler chicken intestine. The addition of probiotic bacteria Bacillus subtilis or phytobiotic containing cinnamon oil to drinking water is more preferable than Enterococcus faecium regarding stimulation of the immune system, blood redox status parameters, parameters of metabolic changes and the gut microbiome and morphometry.

Cassava (Manihot esculenta) root chips inclusion in the diets of broiler chickens: effects on growth performance, ileal histomorphology, and cecal volatile fatty acid production

Exploration and evaluation of alternative feedstuffs in the poultry diets are critical to the industry when the prices of conventional energy sources (i.e., corn and wheat) fluctuate widely and are limited in supply. Cassava root chips (CRC) is rich in energy and fiber, and thus may serve as an alternative energy source in poultry diets, while the fiber in it will undergo microbial fermentation and improve the gut health of broilers. This study evaluated the effects of dietary inclusion of different levels of CRC on the growth performance and gut health parameters of broiler chickens. A total of 180 day-old chicks were allocated randomly to 5 dietary treatments, each with 6 replicate pens. The 5 dietary treatments were the corn-soybean meal-based diets with 0, 12.5, 25, 37.5, and 50% CRC inclusion in the 42-D feeding trial. Ileal histomorphology and cecal volatile fatty acid (VFA) were evaluated as indicators of gut health. Compared to the control group (0% CRC), broiler body weight was not different (P > 0.05) up to 25% CRC inclusion in the starter period (1 to 21 D) and up to 37.5% in the total study period (1 to 42 D). The average daily gain was significantly lower (P < 0.05) at 50% CRC inclusion in the starter period and for the total study period. Feed conversion ratio did not differ (P > 0.05) up to 37.5% CRC inclusion in the starter diet, and up to 50% CRC inclusion in the finisher diet. Villus height, crypt depth, their ratio, and villus surface area were not different among the treatments (P > 0.05). Total VFA and acetate production increased with the increasing dietary inclusion of CRC from 25 to 50%. In conclusion, CRC can be used to replace conventional energy feedstuff (like corn) up to 25 and 37.5% in starter and finisher diets, respectively. Use of CRC in diets may benefit broiler chickens' production by reducing feed costs and contribute to improving gut health.

Growth performance and gastrointestinal responses in heavy Tom turkeys fed antibiotic free corn-soybean meal diets supplemented with multiple doses of a single strain Bacillus subtilis probiotic (DSM29784)1

Growth performance and gastrointestinal (GIT) responses to a single-strain of Bacillus subtilis (SSB) were investigated using 960 Hybrid Converter Toms. A total of 4 iso-caloric and iso-nitrogenous corn-soybean meal-based diets were allocated to 12 replicate cages/pens and fed (ad libitum) in a four-phase feeding program (starter; days 0 to 28, grower-1; days 29 to 56, grower-2; days 57 to 84, and finisher; days 85 to 126). The diets had either 0 (control), 1E+08 (low), 2E+08 (mid) or 1E+09 (high) cfu B. subtilis/kg. Feed intake (FI) and BW were recorded by phase. Excreta samples were collected towards the end of starter and grower-1 phases for apparent retention (AR) of components by marker method and litter moisture, respectively. Selected birds were necropsied on days 28 and 56 for GIT weight and samples for jejunal histomorphology and ceca digesta short chain fatty acids (SCFA). Supplemental SSB had linear and non-linear (P < 0.05) response on BW gain (BWG). Specifically, relative to the control, birds fed low SSB had higher BWG in starter and grower-1 phases whereas bird fed mid and high SSB had lower BWG in grower-2 and birds fed low and mid SSB had higher BWG in finisher phase. Consequently, birds fed low and mid SSB doses were heavier (P < 0.05) than control fed birds at the end of trial. The FCR response to SSB was linear and non-linear (P < 0.05) with birds fed low SSB showing lower FCR than control fed birds in starter, grower-1 and finisher phases. Supplemental SSB had linear and non-linear (P < 0.05) effects on AR of components (DM, ash, crude protein, crude fat, neutral detergent fiber, and gross energy), litter moisture, GIT weight, jejunal histomorphology, and SCFA. Relative to control, birds fed high SSB showed higher AR of components, villi height, day 56 ceca digesta total SCFA concentration, and lower litter moisture. In conclusions, under condition of the current study, growth performance was optimized by low to mid SSB. Improved nutrient retention and indices of gut health suggested higher SSB doses may optimize growth performance under challenging farm conditions.

Lactobacillus casei DBN023 protects against jejunal mucosal injury in chicks infected with Salmonella pullorum CMCC-533

Pullorum disease is one of the most serious poultry diseases. Antibiotic prophylaxis is commonly applied in actual production, but the emergence of drug-resistant strains and drug residues threatens the health of animals and humans. The use of probiotics has become a potential solution for the aforementioned problem. In this study, we investigated the effects of Lactobacillus casei DBN023 (CGMCC-16146) on the intestinal tissue structure and immune functions of the jejunal epithelium in chicks infected with Salmonella pullorum CMCC-533 using histomorphological and immunological methods. A total of 450 newborn chicks were randomly divided into the control group and experimental groups. We used hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), and an enzyme-linked immunosorbent assay (ELISA) to observe the structure of the jejunal mucosa and analyze changes in cytokine and secretory immunoglobulin A (sIgA) levels. The results showed that prophylactic feeding of L. casei DBN023 to chicks significantly increased their jejunum villar height, villar height-to-crypt-depth (V/C) ratio, and muscle thickness; reduced intestinal-crypt depth; and increased the proliferating cell nuclear antigen (PCNA) level compared with S. pullorum infection. L. casei DBN023 enhances intestinal mucosal immunity, regulates cytokine balance, enhances intestinal immune function, and effectively reduces intestinal inflammation. Thus, it protects intestinal tissues and reduces S. pullorum CMCC-533 damage to the intestinal tract.

Effects of Supplementation of Branches and Leaves Trimmed from Tea Plant on Growth Performance, Rumen Fermentation and Meat Composition of Nanjiang Yellow Goats

Simple Summary

The effects of supplementation of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics and meat composition of fattening Nanjiang Yellow goats were studied. Supplementation of 4% BLTT increased final body weight of goats and also increased the activity of superoxide dismutase, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. Supplementation of 4% BLTT decreased the saturated fatty acid C16:0, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). From the present study, it is concluded that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall hence growth performance and meat composition in goats.

Abstract

Thirty-two 6-month-old, healthy Nanjiang Yellow goats (34.6 ± 4.16 kg) were randomly divided into four treatments to evaluate the supplementary effects of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics, and meat composition in fattening goats. The control goats were fed a basal diet. Treatments 1, 2 and 3 were fed 2%, 4% and 6% of BLTT respectively. After a 60 d feeding trial, blood samples were collected for the analysis of the antioxidant profile and goats were slaughtered to obtain the rumen fluid and carcass samples for determination of rumen fermentation characteristics and meat composition perameters. Increased final body weight was observed in goats fed 4% BLTT compared with control. The activity of superoxide dismutase was increased in the 4% BLTT-treated group, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. The saturated fatty acid C16:0 was decreased with 4% of BLTT supplementation, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). To sum up, our findings revealed that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall growth performance and meat quality in goats.

The effects of dietary supplementation with porous zinc oxide on growth performance, intestinal microbiota, morphology, and permeability in weaned piglets

The objective of this experiment was to evaluate the effects of dietary supplementation with porous zinc oxide (HiZox) on growth performance, intestinal microbiota, morphology, and permeability in weaned piglets. A total of 128 weaned piglets [(Landrace × Yorkshire) × Duroc] with an average body weight (BW) of (6.55 ± 0.25 kg; 21 d of age) were randomly assigned to four dietary treatments: (1) a corn-soybean basal diet; (2) basal diet + 3,000 mg/kg conventional ZnO; (3) basal diet + 200 mg/kg HiZox; (4) basal diet + 500 mg/kg HiZox. The experiments lasted for 28 days. Incremental HiZox in the diet increased ADG (linear p = 0.015; quadratic p = 0.043) and ADFI (linear p = 0.027; quadratic p = 0.038), and the diarrhea index decreased linearly and quadratically (p < 0.01) as HiZox supplemented increased. Furthermore, supplementation with HiZox increased the amounts of Lactobacillus spp. (p < 0.05) in the ileum and cecum in comparison with that of control treatment or 3,000 mg/kg ZnO treatment, while decreased the populations of Escherichia coli, Clostridium coccoides, and Clostridium. leptum subgroup (p < 0.05) in the ileum and cecum relative to those in control treatment. The addition of HiZox increased the villus height and villus-to-crypt ratio (VC) of duodenum, jejunum, and ileum (p < 0.05), while decreased the crypt depth of jejunum (p < 0.05) and tended to reduce the crypt depth of duodenum (p < 0.10) compared with the control treatment. Piglets fed with 500 mg/kg HiZox had lower serum D-lactate and diamine oxidase (DAO) than those fed with basal control diet or 3,000 mg/kg ZnO diet (p < 0.01). The results suggested that supplementation with HiZox modulated intestinal microbial composition and improved intestinal morphology, which may exert protective effects on the integrity of the mucosal barrier function of weaned piglets, was as efficacious as pharmaceutical doses of ZnO in enhancing growth performance, indicating that the HiZox may be a promising alternative to pharmaceutical doses of ZnO.

Intestinal Morphology in Broiler Chickens Supplemented with Propolis and Bee Pollen

The aim of this study was to determine the influence of dietary supplementation with propolis and bee pollen on the intestinal morphology and absorptive surface areas of chickens. Two hundred day-old Ross 308 chickens (100 male and 100 female) were equally allocated into five groups. Throughout the whole study, the control group of chickens was fed with a basal diet, while the experimental groups of chickens were fed with the same diet supplemented with propolis and bee pollen: P1 = 0.25 g of propolis/kg + 20 g of bee pollen/kg; P2 = 0.5 g of propolis/kg; P3 = 1.0 g of propolis/kg; P4 = 20 g of bee pollen/kg. The duodenal villi of chickens from all experimental groups were significantly higher and wider (p < 0.001), while their duodenal villi crypts were significantly deeper (p < 0.001) in comparison with these parameters in chickens from the control group. The villus height to crypt depth ratio, as well as the absorptive surface areas of broiler chickens, were significantly increased (p < 0.001) in experimental groups of chickens in comparison with the control group. These findings suggest that dietary supplementation with propolis and bee pollen has a beneficial effect on broilers chickens' intestinal morphophysiology.

Evaluating two multistrain probiotics on growth performance, intestinal morphology, lipid oxidation and ileal microflora in chickens

An experiment was conducted to investigate the supplementation of two commercially available multistrain probiotics as an alternative to antibiotics on growth performance, intestinal morphology, lipid oxidation and ileal microflora in broiler chickens. A total of 280-day-old ROSS 308 mixed-sex broiler chickens with an average initial body weight of 42 ± 0.5 g were randomly divided into four treatments with five replicate cages of 14 birds each cage in a completely randomized design and fed with the following diets for 42 day: (a) control (CON) (antibiotic-free diet), (b) antibiotic (ANT) (CON + Avilamycin 150 g/ton feed), (c) probiotic A (CON + Protexin^® 150 g/ton feed) and (d) probiotic B (CON + Bio-Poul^® 200 g/ton feed). The results showed the broilers fed the ANT diet had greater average daily gain than broilers fed the CON diet during day 1-14 (p < 0.05). At day 42, two birds were randomly selected per replicate for evaluation intestinal morphology, lipid oxidation and ileal microflora. birds fed diet supplemented with probiotic A and probiotic B increased villus height and goblet cells numbers in the jejunum and villus height to crypt depth ratio and villus height in the ileum as compared to birds fed CON diet (p < 0.05). The malondialdehyde value was reduced (p < 0.05) in the ANT, probiotic B and probiotic A groups compared with the CON group. The Lactobacillus population was increased and Clostridium spp. population decreased in the ileum of broilers fed diets containing the probiotic B and probiotic A compared with those fed CON diet (p < 0.05). The results from this study indicate that the probiotic A (Protexin^® ) and probiotic B (Bio-Poul^® ) used in this trial may serve as alternatives to ANT.

Improved growth performance due to hypertrophied intestinal absorptive epithelial cells by heat-killed Lactobacillus sakei HS-1 in broiler chickens1

This study investigated the effect of heat-killed Lactobacillus sakei HS-1 (HK LS HS-1) on the growth performance and intestinal histology of broilers through 2 feeding trials. In trial 1, 48 male broilers were separated into 3 groups: 1) basal diet (1 to 21 d, including antibiotics; 21 to 49 d, not including antibiotics) supplemented with 0 bacterial cells of HK LS HS-1/g (control); 2) 106 bacterial cells were used; and 3) 108 bacterial cells were used. Trial 2 was carried out in a tropical area of Thailand, where 50 7-d-old male broilers were separated into 2 groups: 1) basal diet (control group); and 2) basal diet supplemented with 107 bacterial cells of HK LS HS-1/g. In trial 1, compared with the control, BW gain (linear; P = 0.019) and G:F (linear; P = 0.032) linearly increase with increasing HK LS HS-1 supplementation. In addition, 3 males died in the control group, while none died in the experimental group. In trial 2, growth performance was not significantly different between the groups. Observation of the gross anatomical visceral organs and intestinal histological parameters showed no difference among the groups. However, the weight of the ileum, total small intestine, gizzard, and ceca decreased, while the height of the ileal villus increased with increasing HK LS HS-1 supplementation (P < 0.05). On the duodenal villus apical surface, protuberated cells, cells without microvilli, recently exfoliated regions on villus tips, and deeper cells at the sites of these recently exfoliated cells were more frequently observed in the experimental groups compared to the control; therefore, the duodenal epithelial cells of the experimental groups were hypertrophied by rapid cell turnover. On the ileal villus apical surface, morphological changes (i.e., cell shedding) were not observed, but protuberated cells were observed; thus, the ileal epithelial cells of the experimental groups were hypertrophied by prolonging the detention period of cells on the villus tip without shedding into the intestinal lumen. The results indicate that HK LS HS-1 improves the growth performance of broilers due to the presences of hypertrophied intestinal absorptive epithelial cells on the villus apical surface, which induce enhanced durability against environmental stress.

Efficacy of synbiotic Jerusalem artichoke and Lactobacillus rhamnosus GG-supplemented diets on growth performance, serum biochemical parameters, intestinal morphology, immune parameters and protection against Aeromonas veronii in juvenile red tilapia (Oreochromis spp.)

Synbiotics, a synergistic combination of probiotics and prebiotics, are currently regarded as one of the most practical nutritional supplements in tilapia farms. In this study, the effect of supplementing the diet of red tilapia (Oreochromis spp.) with Jerusalem artichoke (Helianthus tuberosus) and Lactobacillus rhamnosus GG (LGG) was evaluated. Growth performance, serum biochemical parameters, intestinal morphology, goblet cell counts, immune parameters and protection against Aeromonas veronii challenge were determined. The results showed that fish fed with synbiotic-supplemented diets had a significantly higher (P < 0.05) feed conversion ratio (FCR), specific growth rate (SGR), and average daily gain (ADG) than fish fed with a control diet. The synbiotic-supplemented diet increased glucose, total protein and the total cholesterol levels. The absorptive area of the proximal and distal intestine of fish fed on the synbiotic diet was significantly higher (P < 0.05) than in those fed with probiotics (LGG), prebiotic-supplemented diets (JA), and the control diet. Goblet cell counts revealed that the numbers of acid mucous cells, neutral mucous cells and double-staining mucous cells of fish fed the synbiotic-supplemented diet (JA + LGG) were significantly higher (P < 0.05) in the proximal and distal intestine. Fish fed the synbiotic-supplemented diets also exhibited significantly higher (P < 0.05) lysozyme activity. The cumulative mortalities of fish fed with a synbiotic-supplemented diet were significantly lower than those of fish fed other diets. The results suggested the beneficial effect of JA and LGG synbiotic diet on growth performance and health status of red tilapia. Direct administration of JA and LGG in fish feed can be used as a practical nutritional supplement in red tilapia.

Bacillus amyloliquefaciens Spore Production Under Solid-State Fermentation of Lignocellulosic Residues

This study was conducted to elucidate cultivation conditions determining Bacillus amyloliquefaciens B-1895 growth and enhanced spore formation during the solid-state fermentation (SSF) of agro-industrial lignocellulosic biomasses. Among the tested growth substrates, corncobs provided the highest yield of spores (47 × 10¹⁰ spores g^-1 biomass) while the mushroom spent substrate and sunflower oil mill appeared to be poor growth substrates for spore formation. Maximum spore yield (82 × 10¹⁰ spores g^-1 biomass) was achieved when 15 g corncobs were moistened with 60 ml of the optimized nutrient medium containing 10 g peptone, 2 g KH₂PO₄, 1 g MgSO₄·7H₂O, and 1 g NaCl per 1 l of distilled water. The cheese whey usage for wetting of lignocellulosic substrate instead water promoted spore formation and increased the spore number to 105 × 10¹⁰ spores g^-1. Addition to the cheese whey of optimized medium components favored sporulation process. The feasibility of developed medium and strategy was shown in scaled up SSF of corncobs in polypropylene bags since yield of 10 × 10¹¹ spores per gram of dry biomass was achieved. In the SSF of lignocellulose, B. amyloliquefaciens B-1895 secreted comparatively high cellulase and xylanase activities to ensure good growth of the bacterial culture.

Effects of In Ovo Methionine-Cysteine Injection on Embryonic Development, Antioxidant Status, IGF-I and TLR4 Gene Expression, and Jejunum Histomorphometry in Newly Hatched Broiler Chicks Exposed to Heat Stress during Incubation

Sulfur amino acids are typically the first-limiting amino acids (AA) used in protein metabolism in poultry. Therefore, we hypothesized that their utilization in the pre-hatch period would affect embryonic development, IGF-I and TLR4 gene expression, antioxidant status, serum biochemical profile, and jejunum histomorphometry of newly hatched Ross broiler chicks incubated under heat stress conditions. A total of 150 fertile broiler eggs were subjected to heat stress (39.6 °C for 6 h/d) from d10 until d18 and injected at d 17.5 of incubation with methionine and cysteine (Met-Cys) at a dose of 5.90 mg l-methionine plus 3.40 mg l-cysteine. The effects of Met-Cys administration were examined and compared with the control (Non-injected group) and 0.75% NaCl injected group. The results showed that no significant differences among all groups in serum protein profiles (total protein, albumin, globulin, and albumin/globulin ratio) and creatine kinase were observed. The level of heat shock protein-90 was decreased with Met-Cys In ovo injection. The In ovo injection of Met-Cys also improved the values of total antioxidants capacity and glutathione in examined tissues. At the same time, an increase in fold change mRNA abundance of IGF-I and TLR4 was observed after Met-Cys injection in tested tissues. Finally, an increase of 29% in villus area was found after Met-Cys injection compared to the control group. In conclusion, the In ovo injection of Met-Cys resulted in improved embryonic development, IGF-I and TLR4 gene expression, antioxidant status and jejunum histomorphometry of newly hatched broiler chicks exposed to heat stress during incubation.

The beneficial effects of purple yam (Dioscorea alata L.) resistant starch on hyperlipidemia in high-fat-fed hamsters

In this study, we investigated the interventional effect of resistant starch (RS) obtained from purple yam (Dioscorea alata L.) on regulating lipid metabolism and gut microbiota in hyperlipidemic hamsters.

Dietary effects of Bacillus subtilis fmbj on growth performance, small intestinal morphology, and its antioxidant capacity of broilers

This paper aimed to study the dietary effects of Bacillus subtilis fmbj (BS fmbj) on growth performance, small intestinal histomorphology, and its antioxidant capacity of broilers at 21 d of raising. A total of 300 1-d old male Arbor Acres broilers were randomly assigned to 5 groups: broilers fed the basal diets with 0 g/kg BS fmbj (CON), 0.2 g/kg BS fmbj (BS-1), 0.3 g/kg BS fmbj (BS-2), 0.4 g/kg BS fmbj (BS-3), and 0.5 g/kg BS fmbj (BS-4). The results showed that there were no differences in the growth performance among treatments during the trail. Dietary BS fmbj in broiler diets increased (P < 0.05) the serum immunoglobulin A (IgA) and immunoglobulin G (IgG) concentration, and enhanced the secretory immunoglobulin A (sIgA) level of small intestine (jejunum and ileum) compared with those in the CON group. The BS groups could improve (P < 0.05) the values of villus length, villus width, crypt depth, and villus area of small intestine compared with that in the CON group. Compared with the CON group, the BS group increased (P < 0.05) small intestinal antioxidant capacity and its mitochondrial antioxidant capacity, and also improved the antioxidant related-gene expression. The BS group exerted a lower (P < 0.05) level of oxidative damages in small intestine than that of the CON group. In conclusion, dietary BS fmbj in broiler diets was potential to improve the small intestinal histomorphology, small intestinal antioxidant capacity, and its mitochondrial antioxidant capacity. Thus this BS fmbj might be considered to be an important additive for the poultry industry.

Effects of inulin supplementation to piglets in the suckling period on growth performance, postileal microbial and immunological traits in the suckling period and three weeks after weaning

The aim of this study was to investigate the effect of inulin (IN) supplementation to suckling piglets at and 3 weeks post-weaning. A total of 72 newborn piglets were used. Twenty-four piglets per group received different amounts of IN during the suckling period: (a) CON: no IN; (b) IN-0.5: 0.5 g IN/d on the 1st week, 1 g IN/d on the 2nd week, 1.5 g IN/d on the 3rd week and 2 g IN/d on the 4th week, or (c) IN-0.75: 0.75 g IN/d on the 1st week, 1.5 g IN/d on the 2nd week, 2.25 g IN/d on the 3rd week and 3 g IN/d on the 4th week. Starting at 28 d of age, piglets were weaned and received a post-weaning diet without inulin during the following 3 weeks. At both 28 d and 49 d of age, piglets were euthanised for sampling. Piglets of group IN-0.5 had the highest body weight starting from the 3rd week (p < 0.05), concomitant with the highest villus height and the ratio of villus height/crypt depth in the jejunum and ileum on both sampling days (p < 0.05). At 28 d of age, an increased concentration of propionate, iso-butyrate or total short chain fatty acids was observed between treatment IN-0.5 and the other groups in the caecum or colon (p < 0.05). Moreover, the relative abundance of Escherichia coli (p = 0.05) and Enterobacteriaceae (p = 0.01) in colonic digesta were reduced in IN-0.5-treated piglets, and in both IN-supplemented groups, colonic interleukin-8, tumor necrosis factor-α and toll-like receptor-4 mRNA abundance were decreased compared to the CON group (p < 0.05). However, at 49 d of age, most of these differences disappeared. In conclusion, treatment IN-0.5 improved during the suckling period of piglets development of intestine, but these beneficial effects were not lasting after weaning, when IN supplementation was terminated. Treatment IN-0.75, however, did not display a prebiotic effect.