One avian leukosis virus of subgroup J (ALV-J) strain GX14YYA1 was isolated from a commercial bivalent Newcastle disease (ND)-infectious bronchitis (IB) vaccine in our previous study. To evaluate the pathogenicity of the ALV-J-contaminated vaccine on commercial chickens, day-old Three-Yellow chicks in group I were vaccinated with ALV-J-contaminated bivalent ND-IB live vaccine by intranasal and eye drop at 1-day-old for the primary vaccination and at 7-day-old for the secondary vaccination. Groups II and III were kept as the normal vaccination group with the noncontaminated ND-IB vaccine and blank control groups, respectively. The birds of different groups were maintained separately in isolators for 175 d. The first viremia was detected at 4 wk of age and 20% (2/10) of the birds maintained viremia during 11 to 25 wk of age. At the same time, the birds in group I experienced a significant suppression of body weight gain when compared with those of groups II and III (P < 0.05). In addition, the birds in group I showed obvious ALV-J hemangioma-type anatomical lesions in the liver and tumors were observed in the abdominal cavity. The results demonstrated that the ALV-J contaminated commercial live vaccines can induce pathogenicity in commercial Three-Yellow chickens and indicate that ALV-J-contaminated commercial live vaccines could be one of the transmission routes of ALV-J to commercial chickens.
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http://dx.doi.org/10.1016/j.psj.2021.101027 | DOI Listing |
Trop Anim Health Prod
January 2025
Federal Institute of Education, Science, and Technology of Amazonas, Downtown Campus, Manaus, Amazonas, Brazil.
This study evaluated the effects of incorporating biological silage from tambaqui (Colossoma macropomum) by-products (BST) on the performance, hematological and plasma biochemical parameters, and egg quality (physical, proximate composition and sensory characteristics) of older commercial hens. The BST was prepared by ensiling tambaqui by-products with lactic acid bacteria, cassava trimmings, and preservatives, producing a nutrient-rich, high-protein feed ingredient. One hundred and twenty Hisex Brown hens (83 weeks old) were divided into five treatment groups, each receiving diets with 0, 1, 2, 3, or 4% BST.
View Article and Find Full Text PDFMicroorganisms
December 2024
Department of Pathology, Clinical and Toxicological Analysis, Health Sciences Center, State University of Londrina, Londrina 86057-970, Paraná, Brazil.
is a significant pathogen responsible for infections in both humans and livestock, possessing various virulence mechanisms and antimicrobial resistance that make it even more concerning. In this study, several internationally recognized clones of were identified, such as ST131, ST38, ST648, and ST354, from chicken meat, pork, and human infection samples. Notably, ST131, belonging to phylogroup B2, was the dominant sequence type (ST) in human samples, while ST38, belonging to phylogroup D, was the most prevalent in meat samples.
View Article and Find Full Text PDFMicroorganisms
December 2024
Chaire de Recherche en Salubrité des Viandes (CRSV), Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC J2S 2M2, Canada.
Avian necrotic enteritis due to the Gram-positive bacterium has re-emerged following the ban on antibiotic growth promoters in many poultry producing countries. The limited number of previous studies has left important gaps in our understanding of the genetic diversity and virulence traits of the pathogen. To address these knowledge gaps, in this study, we sequenced the genomes of 41 isolates recovered from commercial broiler chicken flocks in Quebec, Canada, including isolates from healthy birds and those affected by necrotic enteritis.
View Article and Find Full Text PDFGenes (Basel)
December 2024
Department of Animal Biotechnology and Genetics, Faculty of Animal Breeding and Biology, Bydgoszcz University of Science and Technology, St. Mazowiecka 28, 85-084 Bydgoszcz, Poland.
Background: stimulation introduces bioactive compounds, such as prebiotics, probiotics, or synbiotics into incubating eggs to enhance gut health and immune system development in chickens. This study aimed to determine the genetic and environmental effects modulating responses to stimulation in commercial broilers and Green-legged Partridge-like (GP) native chickens.
Methods: Eggs were stimulated on day 12 of incubation with prebiotics (GOS-galactooligosaccharides), probiotics ( subsp.
Biology (Basel)
December 2024
College of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China.
The eggshell quality traits in avian species, including Yunnong chickens (YN), are crucial for commercial and breeding purposes. The use of advanced biotechnologies, such as gene sequencing, has become increasingly common for identifying genetic markers and comparing specific traits in livestock. However, genetic markers related to eggshell traits in YN chickens remain unexplored.
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