Search Results (93)

Bacterial chondronecrosis with osteomyelitis (BCO) is a major cause of lameness in broiler chickens. This condition arises when bacteria from the gastrointestinal or aerosol tract migrate to infect bone microfractures, often exacerbated by rapid growth, reduced blood flow, and mechanical stress. As concerns about antibiotic resistance grow, probiotics have gained attention for their potential to improve gut health and reduce systemic bacterial load. This study evaluated the efficacy of a probiotic program comprising an Enterococcus faecium-based spray (2 × 10⁹ CFU/bird at hatch) and a triple-strain Bacillus-based feed additive (B. subtilis 597, B. subtilis 600, and B. amyloliquefaciens 516 at 500 g/t feed from day 1 to 56), applied individually or in combination. A wire-flooring challenge model was used to simulate BCO transmission. A total of 1560 Cobb 500 broilers were randomly assigned to five groups: T1 (positive control), T2 (negative control), T3 (E. faecium spray only), T4 (Bacillus feed supplement only), and T5 (combined treatment). Lameness was evaluated daily from day 21 to 56 through clinical observation and necropsy. The challenge model was validated with >70% lameness in T1. All probiotic treatments significantly reduced lameness compared to T2 (p < 0.05): 35.4% in T3, 36.7% in T4, and 47.6% in T5. The combined treatment resulted in the statistically highest reduction in lameness incidence, indicating a synergistic rather than merely additive effect compared to individual treatments. These findings support the use of targeted probiotic strategies to reduce BCO lameness and enhance skeletal health and welfare in broilers. Full article

The gastrointestinal (GI) tract is under neural, endocrine and paracrine control. The release (basal and in the presence of either cholinergic and opioid antagonists) of Met-enkephalin, insulin-like growth factor 1 (IGF-1) and somatostatin (SRIF) was determined quantitatively in vitro using explants of the crop, proventriculus and duodenum from either day 0 or day 1 chicks. In addition, the effects of cholinergic and opioid antagonists on PENK gene expression were examined. Thus, the aim of this study was to determine the roles of cholinergic and opioid receptors in the GI tract in newly hatched chickens. Moreover, the effect of IGF-1 and Met-enkephalin on cell division in duodenal explants in vitro was determined. There was both the release of Met-enkephalin from, and PENK expression in, the explants of the crop, proventriculus and duodenum tissue. This is the first report of any neuropeptide(s) being synthesized in and/or released from the crop. In vitro release of Met-enkephalin, IGF-1 and SRIF from duodenal and proventriculus explants was influenced (p < 0.01) by either cholinergic or opioid antagonists; for instance, in the presence of atropine, decreases (p < 0.001) of 17.8% and 57.7% are seen, respectively, in Met-enkephalin release and PENK expression in crop explants from day 1 chicks. Moreover, in the presence of atropine, there were increases (p < 0.001) of 47.7% and 70.9% in IGF-1 release in proventriculus explants from, respectively, day 0 and day 1 chicks. Met-enkephalin and/or IGF-1 stimulated the cell division of duodenal explants in vitro. This is the first report of Met-enkephalin release and PENK expression in the avian crop and of the effects of cholinergic or opioid antagonists on these factors. It is also the first report of either cholinergic or opioid control of IGF-1 release in the periphery of any species. There were strong relationships (p < 0.05) between the release of Met-enkephalin and that of IGF-1 in the duodenum and between the release of SRIF and that of IGF-1 in the proventriculus. This is the first report of IGF-1 and Met-enkephalin stimulating (p < 0.001) the proliferation of duodenal cells and, together, exerting a synergist effect. It is concluded that the release of Met-enkephalin, IGF-1 and SRIF from foregut regions is under tonic cholinergic and opioid control. Full article

In poultry production, antibiotics have been excessively used as growth promoters to support well-being and decrease mortality caused by pathogenic microorganisms. The overuse of antibiotics has led to the emergence of antibiotic-resistant bacteria and the presence of antibiotic residues in poultry products. To counteract this problem, probiotics could be used as adjuncts or as substitutes for preserving a diverse and balanced microflora to prevent the colonization and multiplication of pathogenic bacteria in the GI tract. This study aimed to isolate and characterize the potential probiotic properties of lactic acid bacteria from the small intestine of 23-week-old broiler breeders, with the goal of identifying potential probiotic candidates. Four phenotypically healthy broiler breeders were selected, and intestinal contents were aseptically collected and cultured on MRS agar. From the initial pool of 39 colonies, six isolates were identified based on Gram-positive and catalase-negative characteristics and further classified using 16S rRNA sequencing as Levilactobacillus brevis (n = 3), Pediococcus pentosaceus (n = 2), and Streptococcus salivarius (n = 1). These strains were further evaluated for probiotic properties such as transit resistance to simulated upper gastrointestinal conditions, antagonist activity, haemolytic activity, and cell surface properties such as autoaggregation, co-aggregation and hydrophobicity, in vitro. L. brevis NKFS8 showed good tolerance to pH 3, while P. pentosaceus NKSF10 exhibited good tolerance to pH 4 acidic conditions. All isolates demonstrated good survivability in bile salt concentration of 3% (w/v), with P. pentosaceus NKSF10 exhibiting the highest tolerance. The isolates showed a wide range of antagonistic activity against the test pathogens Pseudomonas aeruginosa (ATCC 27853), Salmonella typhimurium, Salmonella enterica (ATCC 13314), Staphylococcus aureus (ATCC 29213), and Listeria monocytogenes (ATCC 7644). Furthermore, these strains exhibited good auto-aggregation, co-aggregation, and hydrophobicity properties. In conclusion, lactic acid bacteria from the small intestine of broiler breeders present a valuable prospect for the development of effective probiotics. These probiotics can be utilized as a supplementary inclusion in poultry feed, obviating the need for antibiotics as growth promoters. Nevertheless, additional in vivo studies are required to closely monitor and assess the effects of probiotics on the gastrointestinal system of chickens. Full article

Recently, there has been a gradual increase in the demand for chicken and eggs. The gut, as the vital place of nutrient digestion and absorption, is highly associated with the development of livestock and poultry and the quality of meat, eggs, and milk. Intestinal stem cells, as an important source of intestinal cell proliferation and renewal, exert a vital effect on repairing injured intestinal epithelial cells and keeping homeostasis. Intestinal stem cell-regulated intestinal epithelial balance is closely controlled and modulated by interlinked developmental loops that maintain cell proliferation and differentiation processes in balance. Some conservative signaling pathways, including the Wnt, Notch, hedgehog, and bone morphogenetic protein (BMP) loops, have been proved to modulate intestinal health in poultry. Meanwhile, studies have revealed the importance of the Hippo pathway in gastrointestinal tract physiology by regulating intestinal stem cells. Moreover, crosstalk between Hippo and other signaling pathways provides tight, yet versatile, regulation of tissue homeostasis. In this review, we summarize studies on the role of the Hippo pathway in the intestine in these physiological processes and the underlying mechanisms responsible via interacting with these signaling pathways and discuss future research directions and potential therapeutic strategies targeting Hippo signaling in intestinal disease. A comprehensive understanding of how these signaling pathways regulate stem cell proliferation, differentiation, and self-renewal will help to understand the regulation of intestinal homeostasis. In addition, it has the capacity for creative ways to govern intestinal damage, enteritis, and associated disorders induced by different factors. Full article

The industrial processing of broiler chickens has become increasingly automated to scale up meat production. However, certain procedures may cause rupture of the gastrointestinal tract, contaminating the products. The objective of this study was to evaluate the efficiency of the removal of visible contaminated broiler carcasses from the slaughter line based on their microbiological quality compared to non-contaminated ones. Carcasses were analyzed for Escherichia coli and aerobic mesophilic microorganisms counts, as well as Salmonella spp. detection. Carcasses with gastrointestinal contamination had significantly higher counts of aerobic mesophilic microorganisms and E. coli than those without contamination. However, carcasses without visible contamination also showed high counts of bacteria, indicative of the hygiene and sanitary concerns during slaughter. Salmonella spp. were detected in both types of carcasses, with no significant difference in the frequency of positive samples. The most frequently identified serovar was Salmonella Minnesota. The most frequently detected bacteria were E. coli, Klebsiella pneumoniae, Citrobacter freundii, and Pseudomonas aeruginosa. In conclusion, both contaminated and non-contaminated carcasses exhibited high bacterial counts, including potentially pathogenic microorganisms, highlighting the need for post-evisceration steps to reduce microbial contamination. Full article

The objective of this study was to compare the effects of applying a 50% wheat grain diet with those of a diet with 3% additional dietary fibre from various sources on the development of broiler chickens’ gastrointestinal tract and its related organs and to model this phenomenon based on data obtained from 35-day-old chickens using multiple regression equations. The use of various structural components, including oat hull (OH), sunflower hull (SH), sugar beet pulp (SBP), and wheat bran (WB), in proportions of 3% of the diet not only affects digestive processes in broiler chickens’ gastrointestinal tract but also causes a change in the length of their intestinal sections or the weight of related organs. These effects can be taken into account when creating an experimental model, the results of which can at least be partially applicable to human studies. The use of OH and SH (3%) in the birds’ diets resulted in a significantly higher body weight (p < 0.05) compared with the use of SBP and WB. OH in the diet significantly increased (p < 0.01) the weight of the chicken’s gizzards compared with the other dietary fibre sources, apart from SH. On the other hand, the weight of the proventriculus in chickens fed the diet containing OH was significantly lower than that of the chickens fed the diet containing SBP (p < 0.05). The use of SH in the diet caused a significant decrease (p < 0.01) in the weight of the chickens’ heart. Compared with other additional sources of dietary fibre, OH in the diet also significantly increased (p < 0.05) the lengths of the small and large intestines, as well as the total length of the intestines. A correlation analysis showed a significant, average, positive relationship (p < 0.05) between the content of TDF in the diet and the weight of the gizzard and indicated a significant positive correlation between the lengths of the jejunum and the remaining sections of the intestines. Additionally, the regression equation models indicated a significant effect (p < 0.01) of all the independent variables on the jejunal, ileal, and caecal lengths and the liver weight. The application of the regression model confirmed significant changes in the small intestine and liver weight depending on the type of dietary fibre and other independent variables, which can also be taken into account when assessing diseases in people with thin intestines. However, further studies with separate models still need to be conducted using experiments including both soluble and insoluble fibre. Full article

The present study investigated the in vitro digestibility of diets for broiler chickens (Ross308) and broiler and laying Japanese quails (Coturnix japonica). The diets contained unconventional feedstuffs such as silkworm (Bombyx mori) meal (SWM) and meals obtained from different Camelina sativa lines (Pearl and Alan, characterized by reduced linoleic acid and glucosinolates content, respectively). An in vitro technique was tested in order to assess its potential for replacing in vivo studies. To test this, the digestive tracts of fifty broiler chickens and four hundred Japanese quails were sampled to extract digestive enzymes to be used for in vitro digestibility assessments, including dry matter digestibility (DMd), organic matter digestibility (OMd), and crude protein digestibility (CPd). Diets including SWM exhibited comparable digestibility values to those of Control diet for broiler chickens, highlighting its potential as a valuable protein source in poultry nutrition. The study also found strong correlations between DMd and OMd (p < 0.01), indicating a logical relationship in nutrient breakdown. A 5% or 10% inclusion of the two camelina lines in the diet for broiler quails did not significantly alter the digestibility parameters (p ≥ 0.05), whereas in laying quails, diets with a 15% inclusion level of camelina resulted in a significant difference in digestibility (p < 0.05). Specifically, oil diets provided the best outcomes, while the diet Pearl Spring 15 showed the lowest DMd, CPd, and OMd (p < 0.05). Overall, results from the present study indicate that the tested alternative feedstuffs (SWM and camelina) have a good potential for poultry feed formulations. In addition, the tested in vitro technique was shown to be more suitable to predict the digestibility of single feedstuffs (i.e., SWM) rather than complete diets, which is consistent with the existing literature. For this reason, this in vitro technique is not adequate to replace in vivo digestibility experiments. Full article

The continuous use of antibiotics is associated with many complications in the poultry industry. Probiotics have emerged as a viable alternative over the past few decades to counter the adverse effects of antibiotics. No candidate probiotic microorganisms have been fully evaluated in the poultry industry for their effectiveness as potential probiotics in guinea fowls (GFs) compared to chickens. Recently, a metagenome evaluation of GFs in our laboratory revealed a predominance of Lactobacillus reuteri (L. reuteri) and actinobacteria class of bacteria in their gastrointestinal tract. The aim of this study is to evaluate a well-known lactic acid probiotic bacterium (L. reuteri) and a unique probiotic (S. coelicolor) that has not been assessed in any guinea fowl species. In the current study, L. reuteri and Streptomyces coelicolor (S. coelicolor) were selected as probiotic bacteria, encapsulated, and added into French guinea fowl (FGF) feed individually at a concentration of 10⁸ cfu/g or both microorganisms combined each at 10⁴ cfu/g. In an 8-week study, 216-day-old guinea keets were randomly assigned to four dietary treatments as indicated: (1) L. reuteri (10⁸ cfu/g); (2) S. coelicolor (10⁸ cfu/g); (3) mixture of L. reuteri (10⁴ cfu/g) and S. coelicolor (10⁴ cfu/g); and (4) control treatment (no probiotics included). The L. reuteri, S. coelicolor, and L. reuteri + S. coelicolor were added into the feed using wheat middlings as a carrier at a final concentration of 10⁸ cfu/g. The FGFs that were fed diets containing L. reuteri showed improved feed consumption at 3–8 weeks of age (WOA). The guineas fed L. reuteri and S. coelicolor showed a lower feed conversion ratio (FCR), which was significant at 2 and 8 WOA, and a numerically lower 8-week average FCR when compared with other dietary treatments. Differences in body weight gain among all dietary treatments were not significant. This research suggests that L. reuteri and S. coelicolor may have the potential for use as probiotics in FGFs when used in combination or separately. Full article

This study aims to clarify the use of Limosilactobaillus reuteri (Lmb. reuteri) in dairy products, emphasizing its main characteristics and limitations through a comprehensive literature review. Lmb. reuteri, previously classified as Lactobacillus reuteri, is a lactic acid bacterium (LAB) generally present in the gastrointestinal tracts of humans and other animals, such as sheep, chickens, and rodents. Lmb. reuteri was reclassified as part of the genus Limosilactobacillus in April 2020, reflecting advancements in biomolecular research that identified distinct metabolic and biochemical characteristics among strains. This species is an important producer of reuterin, an antimicrobial compound facilitated through glycerol fermentation via specific enzymatic pathways. In addition, selected strains of Lmb. reuteri can be considered probiotic bacteria with numerous health benefits and that lead to well-being improvements. It is consistently related to improvements in gut health, immune function enhancement, and cholesterol reduction. Furthermore, its application in dairy products has gained prominence and is increasingly reported in the literature due to its technological and sensory benefits. Despite the challenges of its incorporation into the dairy matrix, largely due to the need to supplement these products, it has already demonstrated significant effects on several dairy products’ technological, sensory, and quality characteristics. Future research should address challenges like strain-specific efficacy and regulatory hurdles for the application of Lmb. reuteri in foods. Full article

Aflatoxin B1 (AFB1) can impair the growth of chickens and reduce the quality of eggs and meat, resulting in significant economic losses. The inclusion of mycotoxin detoxifying agents (MyDA) with binding properties in the diet is an efficient tool to reduce their absorption rate in the gastrointestinal tract. Our aim was to investigate the ability of two innovative MyDA (SeOX, a feed additive featuring a tri-octahedral smectite mixed with lignocellulose, and CHS, a di-octahedral smectite functionalized with an organic non-toxic modifier) in both reducing the bio-accessibility and mitigating the adverse effects of AFB1 in broilers exposed for 10 days to concentrations approaching the European Union maximum limits in feed (0.02 mg/kg). The amount of AFB1 in the excreta of birds, collected over four consecutive days (starting on day 7), was significantly lower (p < 0.001) in the group exposed to AFB1 alone compared to the groups treated with either SeOX or CHS. The calculated bio-accessibility was decreased by nearly 30% with both MyDA. This positive effect was reflected by a significant reduction (p < 0.001) in the oxidative stress (measured as serum antioxidant capacity and hepatic lipid peroxidation) induced by AFB1. Although antioxidant enzyme activities and glutathione levels were unaffected by any treatment, AFB1 significantly induced (p < 0.001) the upregulation of CYP2A6 and the downregulation of Nrf2; the latter was reverted by each MyDA. Overall, these results demonstrate that the selected MyDA are effective in limiting the AFB1 absorption rate, thereby mitigating or even reverting the oxidative stress induced by AFB1 in broilers. Full article

Upcycling brewers’ spent grain (BSG) into poultry feed needs to be optimized. Since broiler chickens inefficiently digest fiber, we created a water-soluble BSG extract (BSGE) to explore this fraction’s potential nutritional benefits. We utilized intra-amniotic administration (in ovo) to target the gastrointestinal tract of broiler embryos. BSGE increased villus surface area and goblet cell quantity and size, implying improved duodenal development. The extract also changed cecal Escherichia coli (E. coli) and Clostridium abundances. Synchrotron X-ray fluorescence microscopy, along with zinc and iron transporter relative expression, did not reveal significant changes by BSGE. These findings highlight the potential for BSGE to be a functional feed component, underscoring the potential value of upcycling this byproduct. This pilot study supports future work exploring the impact of BSGE within feed and its effects over long-term consumption. Full article

Peroxisome proliferator-activated receptors (PPARs) are important targets for cannabidiol (CBD), which mediate many of its biological actions. The hypothesis of the present research assumed that PPARs affect the gut response to different challenge factors in chickens (C. perfringens vs. lipopolysaccharides (LPS) from E. coli), and that CBD can mediate the pathways of this response. The study proved that CBD and the challenge factors significantly affect the expression level of PPARα (p = 0.001) and selected genes determining gut barrier function. A positive correlation was demonstrated between PPARs and genes involved in the formation of tight junctions, immune, and oxidative stress responses in chickens. Dietary supplementation with CBD actively mediated the expression rate of PPARs, but the mechanism of interaction between CBD and PPARs was different depending on the stress factor used. The addition of CBD to the birds’ diets did not contribute to reducing intestinal permeability under induced stress conditions nor cause stress, as indicated by the absence of elevated blood cortisol and endotoxin levels. CBD also supported the mechanisms of protecting intestinal cells from the cytotoxic effects in a C. perfringens challenge through the levels of genes involved in oxidative stress. This study indicates the importance of research toward understanding the mechanisms of PPARs as a target for enhancing intestinal barrier function, provides new results on the biological action of CBD in chickens, and shows a constant PPAR association with the jejunum mucosa of birds. Full article

Broiler chicken lameness caused by bacterial chondronecrosis with osteomyelitis (BCO) is presently amongst the most important economic and animal welfare issues faced by the poultry industry, and the estimated economic loss is around USD 150 million. BCO lameness is associated with multiple opportunistic bacterial pathogens inhabiting the respiratory and gastrointestinal tracts. In cases of immune deficiency resulting from stress, injury, or inflammation of the tissue, opportunistic pathogens, mainly Staphylococcus spp., can infiltrate the respiratory or gastrointestinal mucosa and migrate through the bloodstream to eventually colonize the growth plates of long bones, causing necrosis that leads to lameness. This is the first report of developing a Staphylococcus vaccine against BCO lameness disease in broiler chickens. Electron beam (eBeam) technology causes irreparable DNA damage, preventing bacterial multiplication, while keeping the epitopes of the cell membrane intact, helping the immune system generate a more effective response. Our results show a 50% reduction of lameness incidence in the eBeam-vaccinated chicken group compared to the control. Additionally, the eBeam-vaccinated chickens present higher titer of anti-Staphylococcus IgA, signifying the development of an efficient and more specific humoral immune response. Our data establish the eBeam-killed Staphylococcus vaccine as an effective approach to reducing the incidence of lameness in broiler chickens. Full article

Since the global restrictions on antibiotics in poultry systems, there has been a growing demand for natural and sustainable feed additives for disease prevention and poultry nutrition. This study evaluated the effects of incorporating sugarcane bagasse (SCB) lignin into broiler chicken diets. The performance of the chickens, including body weight, feed intake, and mortality, as well as intestinal histomorphometry, and cecum content pH, microbiota, and volatile fatty acids were assessed. In addition, we also aimed to validate an in vitro gastrointestinal tract (GIT) model developed by Carvalho et al. (2023). One hundred and eight 1-day-old Ross 308 chicks were randomly and equally divided into two groups. The first group was fed a basal diet (BD group), while the second group was fed a basal diet supplemented with 1% (w/w) SCB lignin (BD + SCB lignin group) for 36 days. The in vivo conditions of the chicken GIT were replicated in an in vitro model. In the in vivo study, SCB lignin increased cecum acetate and butyrate levels while reducing Bifidobacterium and Enterobacteriaceae, without affecting productivity (body weight, feed intake, and mortality). The in vitro assessment reflected microbiota trends observed in vivo, although without statistical significance. The divergence in organic acid production between the in vivo and in vitro conditions likely resulted from issues with inoculum preparation. This study demonstrates that SCB lignin incorporation positively influences cecal microbiota composition without impacting the animals’ productivity and physiology, suggesting its potential as a functional feed additive. For a more reliable in vitro model, adjustments in inoculum preparation are necessary. Full article

Coccidiosis in broiler chickens continues to be a major disease of the gastrointestinal tract, causing economic losses to the poultry industry worldwide. The goal of this study was to generate a symptomatic Eimeria maxima (1000 oocysts) infection to determine its effect on the luminal and mucosal microbiota populations (L and M) in the jejunum and ileum (J and IL). Samples were taken from day 0 to 14 post-infection, and sequencing of 16S rRNA was performed using Illumina technology. Infected birds had significantly (p < 0.0001) lower body weight gain (BWG), higher feed conversion ratio (FCR) (p = 0.0015), increased crypt depth, and decreased villus height (p < 0.05). The significant differences in alpha and beta diversity were observed primarily at height of infection (D7). Analysis of taxonomy indicated that J-L and M were dominated by Lactobacillus, and in IL-M, changeover from Candidatus Arthromitus to Lactobacillus as the major taxon was observed, which occurred quicky in infected animals. LEfSe analysis found that in the J-M of infected chickens, Lactobacillus was significantly more abundant in infected (IF) chickens. These findings show that E. maxima infection affects the microbiota of the small intestine in a time-dependent manner, with different effects on the luminal and mucosal populations. Full article