{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T08:45:33Z","timestamp":1791362733496,"version":"4.3.1"},"reference-count":50,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,1,7]],"date-time":"2022-01-07T00:00:00Z","timestamp":1641513600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 32072708 and No. 32102533"],"award-info":[{"award-number":["No. 32072708 and No. 32102533"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key R&amp;D Program of China","award":["2018YFE0128000"],"award-info":[{"award-number":["2018YFE0128000"]}]},{"name":"China Agriculture Research System of MOF and MARA","award":["CARS-41"],"award-info":[{"award-number":["CARS-41"]}]},{"DOI":"10.13039\/501100012421","name":"Agricultural Science and Technology Innovation Program","doi-asserted-by":"publisher","award":["ASTIP-IAS04 and CAASZDRW202005"],"award-info":[{"award-number":["ASTIP-IAS04 and CAASZDRW202005"]}],"id":[{"id":"10.13039\/501100012421","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Salmonella causes significant economic loss to the poultry industry and represents a real threat to human health. The region of difference 21 (ROD21) pathogenicity island removal is a genetic mechanism by which Salmonellaenteritidis (SE) invades the intestinal epithelium and induces systemic infection in mice. The heterophil\/lymphocyte (H\/L) ratio reflects the chicken\u2019s robustness and immune system status. The H\/L ratio is considered a disease resistance trait, and it could be used as a marker for selecting Salmonella resistance in live chickens. However, the association of the H\/L ratio with Salmonella resistance and the inflammatory response remains to be elucidated. Moreover, the kinetics of ROD21 excision in the intestine and immune organs of chickens is unknown. Therefore, this study aimed to investigate the bacterial load, the ROD21 excision, the IL-1\u03b2, IL-8, and INF-\u03b3 blood serum concentration kinetics, and the association with the H\/L ratio in chicken at 1, 3, 7, and 21 days post-SE infection. The results showed a significant correlation between the H\/L ratio and the bacterial load in the ileum and caecum at 7 dpi. The ROD21 pathogenicity island absolute and relative excision in the caecum were positively correlated at 1 dpi but negatively correlated at 7 dpi with the H\/L ratio. However, in the liver, we found the opposite tendency. The association of the H\/L ratio with IL-1\u03b2, IL-8, and INF-\u03b3 blood serum concentrations showed that a low H\/L ratio is correlated with increased IL-1\u03b2 and INF-\u03b3 at 21 dpi. This study confirmed that the H\/L ratio is associated with robustness and Salmonella-resistance in chicken. The methodology used in this study can separate individuals into susceptible and resistant and can help in the selection and breeding of Salmonella-resistant chickens.<\/jats:p>","DOI":"10.3390\/pathogens11010072","type":"journal-article","created":{"date-parts":[[2022,1,9]],"date-time":"2022-01-09T20:21:56Z","timestamp":1641759716000},"page":"72","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Investigation of the Potential of Heterophil\/Lymphocyte Ratio as a Biomarker to Predict Colonization Resistance and Inflammatory Response to Salmonella enteritidis Infection in Chicken"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2533-3720","authenticated-orcid":false,"given":"Mamadou","family":"Thiam","sequence":"first","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Astrid Lissette","family":"Barreto S\u00e1nchez","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Wen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guiping","family":"Zhao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiao","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1146\/annurev-animal-061220-023200","article-title":"Strategies to Improve Poultry Food Safety, a Landscape Review","volume":"9","author":"Ricke","year":"2021","journal-title":"Annu. 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