Search Results (509)

Sternal bursitis is an underexplored lesion in poultry, often overlooked in microbiological diagnostics. In this study, we characterized 36 Escherichia coli isolates recovered from sternal bursitis in broiler chickens, combining phenotypic antimicrobial susceptibility testing, PCR-based screening, and whole genome sequencing (WGS). The genetic analysis revealed a diverse population spanning 15 sequence types, including ST155, ST201, and ST58. Resistance to tetracycline and ciprofloxacin was common, and several isolates carried genes encoding β-lactamases, including blaTEM-1B. Chromosomal mutations associated with quinolone and fosfomycin resistance (e.g., gyrA p.S83L, glpT_E448K) were also identified. WGS revealed a high number of virulence-associated genes per isolate (58–96), notably those linked to adhesion (fim, ecp clusters), secretion systems (T6SS), and iron acquisition (ent, fep, fes), suggesting strong pathogenic potential. Many isolates harbored virulence markers typical of ExPEC/APEC, such as iss, ompT, and traT, even in the absence of multidrug resistance. Our findings suggest that E. coli from sternal bursitis may act as reservoirs of resistance and virulence traits relevant to animal and public health. This highlights the need for including such lesions in genomic surveillance programs and reinforces the importance of integrated One Health approaches. Full article

Proteomics combined with peptidomics approaches were used to analyze the protein degradation and the release pattern of umami peptides in stewed chicken. The results showed that a total of 422 proteins were identified, of which 273 proteins consistently existed in samples stewed for 0–5 h. Myosin heavy chain exhibited the highest abundance (26.29–30.26%) throughout the stewing process. The proportion of proteins under 20 kDa increased progressively with the duration of stewing and reached 61% at 4–5 h of stewing. A total of 8018 peptides were detected in the soup samples, and 2323 umami peptides were identified using the prediction platforms iUmami-SCM, UMPred-FRL, Umami_YYDS, and TastePertides-DM. Umami peptides derived from titin (accession number A0A8V0ZZ81) were determined to be the most abundant, accounting for 24% of the total umami peptides, and Val534 and Lys33639 were the key N-terminal and C-terminal amino acids of these umami peptides. Abundance analysis showed that the umami peptides KK16 and SK18 ranked among the top 5 in the samples stewed for 0–5 h, and they were most abundant in the 3 h stewed samples. The results obtained will provide data support for promoting the industrialization of high-quality chicken soup products. Full article

The Luhua chicken is an outstanding local breed in China that has been placed under conservation due to the impact of specialized breeding and the widespread adoption of commercial varieties. As such, this study analyzed reproductive traits across three consecutive generations and utilized whole-genome resequencing data from 60 Luhua chickens to assess conservation efficacy through genetic diversity, run of homozygosity (ROH) distribution, kinship, and population structure so as to better conserve the breed. The results show that, across generations, the body weight at first egg increased, the age at first egg was delayed, and the egg weight at first laying increased. No significant variations were found in the body weight at 300 d or the total egg number. The key genetic parameters of the polymorphism information content (PIC), expected heterozygosity (HE), observed heterozygosity (HO), and mean identical-by-state (IBS) distance were 0.234, 0.351, 0.277, and 0.782, respectively. The majority of ROHs ranged from 0.5 to 1 Mb, and the inbreeding coefficient based on ROHs was calculated at 0.021. The findings reveal that these traits remained unchanged across the three generations. Our research suggests that optimizing the mating plan of Luhua chickens is essential to minimize inbreeding risk. Furthermore, the methodology applied in this study provides a valuable reference for the conservation monitoring of other indigenous chicken breeds. Full article

To accelerate breeding progress for egg production traits in Lindian chickens, the genetic parameters for egg production and clutch-related traits in Lindian chickens were evaluated in the present study. Data regarding the age at first egg (AFE), egg number (EN), average clutch length (ACL), and average pause length (APL) were collected from two generations of Lindian chickens based on individual egg production records at 32 weeks of age (32–wk), 43–wk, and 52–wk. The results showed that the AFE of Lindian chickens was 179.3 d of age, with a heritability of 0.35. The heritability was 0.26 for EN32, 0.28 for EN43, and 0.34 for EN52. ACL showed moderate-to-high heritability (h² = 0.3–0.54), but APL traits showed low heritability (h² = 0.09–0.14). There were high positive genetic and phenotypic correlations for EN in the three periods from the start of laying up to 32–wk, 43–wk, and 52–wk. EN had high negative genetic correlations with AFE (r_G = −0.47–−0.80) and high positive genetic correlations with ACL (r_G = 0.45–0.81). The correlation between EN and APL was positive for 32–wk and 43–wk, but negative for 52–wk. These results indicated that the egg production of Lindian chickens could be improved by the selection of AFE, early EN, and ACL. Full article

The Lueyang black-bone chicken represents a distinct indigenous avian breed native to China and it is a slow-growing broiler breed. The gut, whose primary function is to digest food and absorb nutrients, is also home to a large and diverse microbial community. The intestinal morphology, intestinal metabolites, and gut microbiota are critical determinants of nutrient utilization efficiency and immune health in poultry. This study investigates the impact of two distinct rearing modalities—cage-raised (CR) and cage-free (CF)—on the intestinal morphology, intestinal metabolites, and gut microbiota of the duodenum and cecum in Lueyang black-bone chickens. Additionally, we have integrated metabolomics and microbiome analyses. Morphological assessments revealed that, in comparison to the CR group, the CF group exhibited a significant increase in duodenal villi height (VH) and crypt depth (CD) (p < 0.01). Furthermore, there was a notable increase in the number of intestinal inflammatory cells within the CF group. Non-targeted metabolomics indicated an upregulation of omega-3 series polyunsaturated fatty acids and bile acid metabolites in the CR group. Conversely, the CF group demonstrated significantly elevated levels of lysophosphatidylcholine (LPC) and phosphatidylcholine (PE) in the intestine. Microbiome analysis revealed that in the duodenum, beneficial bacteria (e.g., Lactobacillus) were the dominant genera in the CF group, while the Bacteroides predominate in the CR group. Correlation analyses indicated a positive association between LPC levels and the presence of eight bacterial genera, including Ureaplasma. The omega-3 series polyunsaturated fatty acids were positively correlated with three bacterial genera, such as Flavobacterium. Notably, bile acid metabolites exhibited a significant positive correlation with Rikenellaceae_RC9_gut_group. In conclusion, this study provides novel insights into how rearing methods influence intestinal morphology, intestinal metabolites, and gut microbiota, offering a new perspective for the scientific management of poultry with the premise of ensuring animal health and welfare. Full article

Vertebrate molecular genetic research methods typically employ single genetic loci (monolocus markers) and those involving a variable number of loci (multilocus markers). The former often employ microsatellites that ensure accuracy in establishing inbreeding, tracking pan-generational dynamics of genetic parameters, assessing genetic purity, and facilitating genotype/phenotype correlations. They also enable the determination and identification of unique alleles by studying and managing marker-assisted breeding regimes to control the artificial selection of agriculturally important traits. Microsatellites consist of 2–6 nucleotides that repeat numerous times and are widely distributed throughout genomes. Their main advantages lie in their ease of use for PCR amplification, their known genome localization, and their incredible polymorphism (variability) levels. Robust lab-based molecular technologies are supplemented by high-quality statistics and bioinformatics and have been widely employed, especially in those instances when more costly, high throughput techniques are not available. Here, we consider that human and livestock microsatellite studies have been a “roadmap” for the genetics, breeding, and conservation of wildlife and rare animal breeds. In this context, we examine humans and other primates, cattle and other artiodactyls, chickens and other birds, carnivores (cats and dogs), elephants, reptiles, amphibians, and fish. Studies originally designed for mass animal production have thus been adapted to save less abundant species, highlighting the need for molecular scientists to consider where research may be applied in different disciplines. Full article

Infectious bursal disease (IBD) is a viral disease that most commonly affects young chickens and destroys lymphocytes, leading to immunosuppression. The field study aimed to investigate the effect of three different vaccines administered in ovo against IBD and spray against Newcastle disease (ND) on serological response tested for IBD and ND and histopathological analysis of the bursa of Fabricius (BF) and quantitative B lymphocytes in BF in broiler chickens. The study was conducted on a farm of four hen houses with 30,000 chicks in each building. Three different vaccination programs were used in the poultry hatchery, and one hen house IV was not vaccinated. All three groups were vaccinated at 18 days and 9 h in ovo during egg transfer against IBD at a dose of 0.05 mL/embryo, group I vector vaccine (strain vHVT013-69), group II immunocomplex vaccine (strain Winterfield 2512), group III immunocomplex vaccine (strain M.B, 0.05). Then, after hatching, the chicks were vaccinated in a spray (groups I, II, and III) against NDV (strain VG/GA, 20 mL/100 birds) and infectious bronchitis (IBV) in a spray (strain H-120, serotype Mass, and strain CR88121, serotype 793B) at a dose of 20 mL/100 chicks. On days 1, 21, 31, and 41, blood was collected for serological tests to determine the antibody titer against IBD, which was performed using two tests (IDEXX and ID-Vet) and against ND. During the necropsy of birds on days 21 and 31, the bursae of Fabricius were collected from five chickens for histopathological evaluation of BF and quantitative B lymphocyte counts; a total of 40 bursae were analyzed (10 per group). The vaccination program applied significantly (p < 0.05) affected the immune response expressed as a geometric mean titer (GMT) in the serum of the examined chickens against IBDV on days 21, 31, and 41. Differences were also demonstrated in the mass and level of BF damage and the number of B lymphocytes. No significant differences were demonstrated in the GMT in the serum of the examined chickens against NDV depending on the vaccination program applied. Full article

The Japanese government established Japan Agriculture Standards (JAS) in 1999 for the production of chicken meat using native Japanese chicken breeds, abbreviated as ‘Jidori JAS’, for the effective use of native chickens. “Jidori” means “native chickens” in Japanese. The Jidori JAS has designated the Japanese chicken breeds that were established in Japan and/or imported before the end of the Meiji period (until 1912). According to the Jidori JAS, the percentage of native blood in chickens to be marketed as certified Jidori JAS must be 50% or more. This indicates that the Japanese government has permitted the commercial production of hybrid chickens under the Jidori JAS certification. Jidori JAS was introduced to increase the number of chicks available for fattening and improve the growth performance of Jidori JAS certified production. While farmers have to buy chicks from hatcheries each time they produce poultry, this ensures stable production, and the meat quality of the chicken remains consistent. It should be noted that Jidori JAS certification does not guarantee a specific flavor for Jidori meat products. Currently, marker-assisted selection for growth improvement has been successfully implemented in Japan for several Jidori JAS-certified chickens, enhancing their growth performance. Full article

Background: The presence of C. perfringens in chicken meat products leads to significant economic losses for the industry and is associated with human food poisoning. It inspires creative answers for novel substances and techniques, such natural antibacterials, for improved prospects in the future. The objective of this study was to examine the antibacterial properties of thymus and star anise extracts for the suppression of Clostridium perfringens in products made from chicken meat. Methods: Thymus and star anise extracts were phytochemically analyzed using the Folin–Ciocalteu spectrophotometric method, High-Performance Liquid Chromatography (HPLC) to determine the phenolic compounds, DPPH to determine the antioxidant activity, and the agar disk diffusion assay to determine the antibacterial effect of the star anise. Following treatment with the mixture extract, an experimental application was conducted on chicken burgers. C. perfringens was also found in poultry samples. Lastly, the sensory evaluation of the chicken burger was detected. Results: The findings showed that Clostridium perfringens was present in a large number of chicken meat products, with a significant concentration in chicken thighs (84%), as well as in the mixture extract has the largest concentration of phytochemical components (TPC:123.88 ± 7.42 mg GAE/g, TFC: 69.04 ± 6.37 mg quercetin/g) with strong antibacterial action (the minimum inhibitory concentration (MIC) of the mixed extract was 3.12 mg/mL, with an inhibition zone of 13.06 ± 0.91 mm). Also, the addition of mix. extract to chicken burgers extends their shelf life, particularly when the mix content is high. Additionally, the mix. extract shows non-significant effect (p < 0.05) on the chicken burger’s sensory qualities. Conclusions: Finally, we can make use of the mix. extract of thymus and star anise as a natural preservative in chicken meat products especially the chicken burger. Full article

Fibrosarcomas represent a rare but highly aggressive tumor entity among soft tissue tumors. Due to its rarity, questions regarding its development and pathophysiology remain unclear. The chorioallantoic membrane (CAM) assay represents an easily available method to investigate tumors on a growth membrane, live and in ovo. The following study was established to test whether the growth of fibrosarcoma spheroids on the CAM was possible and to critically review their applicability for downstream investigations. The shells of fertilized chicken eggs were opened and the previously prepared HT1080 cell spheroids (50,000, 75,000, and 100,000 cells per spheroid) were applied to the CAM. After 7 days, tumors were examined for size, weight, and vascularization. After 7 days, 80 of 163 chicken eggs showed sufficient tumor growth. Of these 80 eggs with confirmed tumor growth, 32 (40%) were from the 50,000 spheroid group, 18 (22.5%) were from the 75,000 spheroid group, and 30 (37.5%) were from the 100,000 spheroid group. The 100,000-cell spheroid group exhibited the highest weights, with a mean of 110.7 mg, as well as tumor size expansion. This cell number also showed the highest vascularization rates. Tumor growth of fibrosarcoma spheroids could successfully be initiated on the CAM. Consequently, the CAM assay presents a good base for future studies involving human fibrosarcoma cell spheroids. Full article

In ovo administration of probiotics has the potential to enable the early colonization of the gut microbiota, providing health benefits from the onset of life. This study aimed to assess the impact of in ovo probiotic inoculation combined with early posthatch feeding on intestinal development and colonization by Campylobacter spp., immune system development, and the final production performance of chickens. On the 18th day of incubation, Bacillus subtilis, Lactobacillus fermentum, Enterococcus faecium, or physiological saline (control) was administered to Ross 308 eggs in ovo, and chicks had immediate access to feed and water upon hatching. On the 7th, 21st, and 35th days after hatching, samples of tissues were taken for histomorphometric analysis. Campylobacter strains in the cecal content were quantitatively evaluated. Probiotic administration had a beneficial effect on the development of the small intestine and increased the number of B cells in the spleen and the number of B and CD4⁺ cells in the cecal tonsils. The in ovo administration of probiotics did not reduce Campylobacter jejuni colonization and even led to increased bacterial loads in some groups by day 35. However, when combined with early feeding, in ovo probiotic administration had a positive impact on the development of the small intestine and peripheral immune organs. Full article

Background: As one of the most important poultry species worldwide, chickens provide substantial amounts of meat, eggs, and other products for human consumption. With continuous improvements in living standards, consumer demand for high-quality animal products is increasing, making it essential to understand the genetic basis of key traits such as egg production, meat quality, and disease resistance for targeted genetic improvement. Methods: In this study, a number of the candidate genes associated with important traits in chickens were screened by various comparative genomics analysis methods. To further clarify the relationship between these candidate genes and important traits in chickens, they were functionally annotated through the KOG, GO, and KEGG databases. Results: These candidate genes are mainly concentrated in the functional categories of transcription and signal transduction mechanisms and are involved in biological processes such as cyclic nucleotide biosynthesis and intracellular signaling, which involve signaling pathways such as ECM–receptor interactions and calcium signaling. Conclusions: Based on the annotation results from various databases, a functional search of the candidate genes and related literature reports, the following results were obtained: genes such as TBX22, LCORL, and GH were associated with chicken growth traits; genes such as A-FABP, H-FABP, and PRKAB2 were associated with chicken meat quality; genes such as IGF-1, SLC25A29, and WDR25 were associated with chicken reproductive traits; and genes such as C1QBP, VAV2 and IL12B were associated with chicken disease resistance traits. Overall, the findings of this study provide novel insights and candidate genes for genetic improvements in chickens, laying a foundation for future research and breeding strategies targeting key economic traits. Full article

The objective of this study was to estimate the genetic parameters of the egg-laying traits of hens after long-term selection. Four lines were derived from Taiwan indigenous chickens conserved in situ by the National Livestock Biodiversity Program. A total of 9834 hens’ laying records from 18 non-overlapping generations classified as seven generational stages from 2006 to 2023 was used. The traits evaluated included body weight at 16 weeks of age, age at the first egg (Sday), body weight change between Sday and 40 weeks of age (Gain40), mean egg weight at 40 weeks of age (EW40), and egg number up to 40 weeks of age (EN40). A four-trait animal model via the REML procedure was used to estimate the variance/covariance components for each generational stage within each line. The ranges of the heritability estimates for Sday, Gain40, EW40, and EN40 were 0.09–0.61, 0.03–0.70, 0.32–0.83, and 0.00–0.65, respectively. Within the lines’ generational stages, most of the heritability estimates of Gain40 and EW40 were higher than those of Sday and EN40. Also, less fluctuation was found in the heritability estimates of Gain40 and EW40 among the generational stages within the lines. Favorable negative genetic and phenotypic correlations between Sday and EN40 were observed at the last generational stage, which could be beneficial for future breeding programs to improve egg production. Full article

Aging leads to ovarian degeneration in poultry, reducing egg production and quality. Ellagic acid (EA), a natural plant-derived compound, may help delay ovarian aging, though its precise mechanisms remain unclear. This study investigated the effects of EA on ovarian aging of low-yield laying chickens and explored its underlying mechanism. EA supplementation (100 and 500 mg/kg) significantly increased ovarian weight as well as the number and proportion of small yellow follicles in aging chickens. EA administration elevated serum antioxidant levels and upregulated the expression of glutathione peroxidase 4 (GPX4) expression to reduce oxidative stress. Importantly, EA treatment suppressed the mRNA and protein expression of ferroptosis markers transferrin receptor protein 1 (TFRC) and solute carrier family 7 member 11 (SLC7A11), increased Proliferating Cell Nuclear Antigen (PCNA) expression, and alleviated G1 phase arrest in granulosa cells (GCs), promoting cell proliferation, which improves egg quality and production. Furthermore, in vitro experiments demonstrated that EA treatment decreased reactive oxygen species production, improved mitochondrial function, inhibited ferroptosis, and attenuated GCs aging. In conclusion, this study reveals the critical role of ferroptosis in chicken ovarian aging and suggests that EA may provide a promising approach for delaying ovarian aging and enhancing productivity in low-yield poultry. Full article

The etiology of transmissible viral proventriculitis (TVP) of broiler chickens has been discussed since its initial recognition 40 years ago. Regardless of its low direct impact on mortality rate, it leads to high economic losses in the broiler industry through reduction of food conversion, weakening of birds, and their increased susceptibility to pathogens. The aim of the present study was to examine the potential presence of TVP on the broiler chicken farms in Bosnia and Herzegovina, to characterize microscopic lesions, and to investigate the viruses implicated in etiology of TVP by PCR-based methods. In total, 143 diseased broiler chickens from 16 farms in Bosnia and Herzegovina were euthanized and subjected to necropsy and subsequent histopathology of proventriculi. A representative number of proventriculi samples (n = 50) that exhibited histopathologic changes were processed for molecular detection of chicken proventricular necrosis virus (CPNV), girovirus (GyV3), chicken anemia virus (CAV), and infectious bursal disease virus (IBDV) by PCR-based methods. In addition, samples of bursa of Fabricius (n = 39) and spleen (n = 50) were tested for IBDV. Histopathology revealed changes consistent with TVP in 39.8% (57/143) and LP (lymphocytic proventriculitis) in 2.1% (3/143) of samples. All 50 proventricular samples showed positivity to CPNV with Ct values ranging between 18 and 26. GyV3 was detected in eight samples (16%), with Ct values ranging from 11.1 to 27.5. The presence of CAV was more prominent (38%), with 19 positive broiler chickens (Ct ranging from 9.6 to 35.6). Pooled samples of spleen, bursa, and proventriculi from three farms were positive for IBDV. The obtained results represent the first documented data on TVP and the first record of CPNV and GyV3 presence in broiler farms from Bosnia and Herzegovina. Full article