{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T06:04:05Z","timestamp":1777356245722,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,9,29]],"date-time":"2021-09-29T00:00:00Z","timestamp":1632873600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The current study aimed to investigate the potential use of nano-bromocriptine in improving the laying performance of late laying hens by modulating the prolactin gene expression. A total of 150 NOVOgen brown laying hens aged 70 weeks were randomly allocated into three groups of 50 birds each. The first group was kept as a control, while the second and the third groups were treated with bromocriptine and nano-bromocriptine, respectively, at a dose of 100 \u00b5g\/kg body weight per week. The pause days, egg production, feed per dozen egg, and Haugh unit were determined on a monthly basis. Also, the relative prolactin gene expression in the pituitary gland was quantified using qPCR and the number of the ovarian follicles was determined after slaughtering at the 84th week of age. It was found that nano-bromocriptine and bromocriptine improved egg laying performance with minimal pause days, reduced feed per dozen egg, and depressed the relative prolactin gene expression; however, nano-bromocriptine treatment was significantly effective compared to bromocriptine. In conclusion, nano-bromocriptine might be beneficial for elongating sequences and reducing pauses.<\/jats:p>","DOI":"10.3390\/ani11102842","type":"journal-article","created":{"date-parts":[[2021,9,29]],"date-time":"2021-09-29T08:27:44Z","timestamp":1632904064000},"page":"2842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Impact of Nano-Bromocriptine on Egg Production Performance and Prolactin Expression in Layers"],"prefix":"10.3390","volume":"11","author":[{"given":"Ahmed","family":"Dawod","sequence":"first","affiliation":[{"name":"Department of Husbandry and Animal Wealth Development, Faculty of Veterinary Medicine, University of Sadat City, Menofia 32897, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noha","family":"Osman","sequence":"additional","affiliation":[{"name":"Department of Husbandry and Animal Wealth Development, Faculty of Veterinary Medicine, University of Sadat City, Menofia 32897, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanim S.","family":"Heikal","sequence":"additional","affiliation":[{"name":"Department of Husbandry and Animal Wealth Development, Faculty of Veterinary Medicine, University of Sadat City, Menofia 32897, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Korany A.","family":"Ali","sequence":"additional","affiliation":[{"name":"Center of Excellence for Advanced Science, Advanced Materials and Nanotechnology Group, Applied Organic Chemistry Department, National Research Centre, Dokki, Giza 12622, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Omaima M.","family":"Kandil","sequence":"additional","affiliation":[{"name":"Center of Excellence for Embryo and Genetic Resources Conservation Bank, Department of Animal Reproduction and Artificial Insemination, Veterinary Research Division, National Research Center, Dokki, Giza 12622, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Awad A.","family":"Shehata","sequence":"additional","affiliation":[{"name":"Avian and Rabbit Diseases Department, Faculty of Veterinary Medicine, University of Sadat City, Menofia 32897, Egypt"},{"name":"Research and Development Section, PerNaturam GmbH, 56290 G\u00f6denroth, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hafez M.","family":"Hafez","sequence":"additional","affiliation":[{"name":"Institute of Poultry Diseases, Free University Berlin, 14195 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hamada","family":"Mahboub","sequence":"additional","affiliation":[{"name":"Department of Husbandry and Animal Wealth Development, Faculty of Veterinary Medicine, University of Sadat City, Menofia 32897, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,29]]},"reference":[{"key":"ref_1","unstructured":"FAO (2021, July 15). 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