Department of Poultry Science, Mississippi State University, MS 39762, USA.
DSM Nutritional products, Parsippany, NJ, 07054, USA.
Poult Sci. 2024 Oct;103(10):104098. doi: 10.1016/j.psj.2024.104098. Epub 2024 Jul 14.
Investigations were performed to determine the systemic immune and small intestine (SI) morphological responses of Ross 708 broilers to the Marek's Disease vaccine (MDV) administered alone or in conjunction with the in ovo and dietary administration of calcifediol (25OHD). Live embryonated hatching eggs were assigned at random to 3 in ovo treatments at 18 d of incubation. Pre-specified in ovo treatments were: commercial MDV-alone-injected (50 µL) or commercial MDV containing 1.2 (MDV+25OHD-1.2) or 2.4 (MDV+25OHD-2.4) μg of 25OHD. A noninjected control treatment was also included. For the growing phase, broilers received a commercial diet containing 250 IU of vitamin D /kg (control) or a commercial diet supplemented with 2,760 IU of 25OHD /kg (Hy-D diet). For determination of serum IgG, nitric oxide, and α-1-acid glycoprotein (AGP) at 14 and 40 d of age (doa), blood was collected from 1 bird per pen (48 total). In the duodenum, jejunum, and ileum of the same bird, villus length (VL), crypt depth (CD), VL to CD ratio (VCR), and villus surface area were also determined. There were no significant dietary x in ovo treatment interactions for any of the variables examined. However, birds fed Hy-D diets had lower serum AGP levels at 14 doa when compared to those fed un-supplemented commercial diets. Additionally, at 40 doa, birds in the MDV+25OHD-1.2 and MDV+25OHD-2.4 treatments experienced a decrease in serum AGP in comparison to those belonging to the noninjected and MDV-alone treatment groups. A higher jejunal VCR was observed at 14 and 40 doa in birds that belonged to the MDV+25OHD-1.2 treatment when compared to those in the noninjected and MDV-alone treatment groups, and dietary Hy-D increased the VL of the duodenum and jejunum in birds at 14 and 40 doa when compared to those fed the commercial diet. In conclusion, both dietary or in ovo administration of 25OHD lowered inflammatory reactions and improved the SI morphology of broilers that were in ovo-injected with the MDV.
研究旨在确定罗斯 708 肉鸡对马立克氏病疫苗（MDV）的全身免疫和小肠（SI）形态反应，该疫苗单独或与胚内和饮食给予钙三醇（25OHD）联合使用。活胚蛋在孵化 18 天时随机分配到 3 种胚内处理中。预先指定的胚内处理包括：商业 MDV 单独注射（50 μL）或含有 1.2（MDV+25OHD-1.2）或 2.4（MDV+25OHD-2.4）μg 25OHD 的商业 MDV。还包括非注射对照处理。在生长阶段，肉鸡接受含有 250IU 维生素 D/kg（对照）的商业饮食或补充有 2760IU 25OHD/kg（Hy-D 饮食）的商业饮食。为了确定 14 和 40 日龄（doa）时血清 IgG、一氧化氮和α-1-酸性糖蛋白（AGP），从每个鸡舍采集 1 只鸡的血液（共 48 只）。在同一只鸡的十二指肠、空肠和回肠中，还测定了绒毛长度（VL）、隐窝深度（CD）、VL 与 CD 的比值（VCR）和绒毛表面积。在检查的任何变量中，饮食与胚内处理之间都没有显著的相互作用。然而，与未补充商业饮食的鸡相比，Hy-D 饮食组的鸡在 14 doa 时血清 AGP 水平较低。此外，在 40 doa 时，与非注射和 MDV 单独处理组相比，MDV+25OHD-1.2 和 MDV+25OHD-2.4 处理组的鸡血清 AGP 降低。与非注射和 MDV 单独处理组相比，14 和 40 doa 时，属于 MDV+25OHD-1.2 处理组的鸡的空肠 VCR 更高，与商业饮食相比，Hy-D 饮食增加了鸡的十二指肠和空肠的 VL。总之，胚内或饮食给予 25OHD 均可降低 MDV 胚内注射鸡的炎症反应，改善 SI 形态。
