Vailati-Riboni M, Coleman D N, Lopreiato V, Alharthi A, Bucktrout R E, Abdel-Hamied E, Martinez-Cortes I, Liang Y, Trevisi E, Yoon I, Loor J J
Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana, Urbana, IL, 61801, USA.
Department of Animal Sciences, Food and Nutrition (DIANA), Università Cattolica del Sacro Cuore, 29122, Piacenza, Italy.
J Anim Sci Biotechnol. 2021 Apr 8;12(1):62. doi: 10.1186/s40104-021-00560-8.
We aimed to characterize the protective effects and the molecular mechanisms of action of a Saccharomyces cerevisiae fermentation product (NTK) in response to a mastitis challenge. Eighteen mid-lactation multiparous Holstein cows (n = 9/group) were fed the control diet (CON) or CON supplemented with 19 g/d NTK for 45 d (phase 1, P1) and then infected in the right rear quarter with 2500 CFU of Streptococcus uberis (phase 2, P2). After 36-h, mammary gland and liver biopsies were collected and antibiotic treatment started until the end of P2 (9 d post challenge). Cows were then followed until day 75 (phase 3, P3). Milk yield (MY) and dry matter intake (DMI) were recorded daily. Milk samples for somatic cell score were collected, and rectal and udder temperature, heart and respiration rate were recorded during the challenge period (P2) together with blood samples for metabolite and immune function analyses. Data were analyzed by phase using the PROC MIXED procedure in SAS. Biopsies were used for transcriptomic analysis via RNA-sequencing, followed by pathway analysis.
DMI and MY were not affected by diet in P1, but an interaction with time was recorded in P2 indicating a better recovery from the challenge in NTK compared with CON. NTK reduced rectal temperature, somatic cell score, and temperature of the infected quarter during the challenge. Transcriptome data supported these findings, as NTK supplementation upregulated mammary genes related to immune cell antibacterial function (e.g., CATHL4, NOS2), epithelial tissue protection (e.g. IL17C), and anti-inflammatory activity (e.g., ATF3, BAG3, IER3, G-CSF, GRO1, ZFAND2A). Pathway analysis indicated upregulation of tumor necrosis factor α, heat shock protein response, and p21 related pathways in the response to mastitis in NTK cows. Other pathways for detoxification and cytoprotection functions along with the tight junction pathway were also upregulated in NTK-fed cows.
Overall, results highlighted molecular networks involved in the protective effect of NTK prophylactic supplementation on udder health during a subclinical mastitic event.
我们旨在表征酿酒酵母发酵产物（NTK）在应对乳腺炎挑战时的保护作用及其分子作用机制。18头处于泌乳中期的经产荷斯坦奶牛（每组n = 9头）在45天内（第1阶段，P1）饲喂对照日粮（CON）或添加19克/天NTK的CON日粮，然后在右后乳房注入2500 CFU乳房链球菌（第2阶段，P2）。36小时后，采集乳腺和肝脏活检样本，并开始抗生素治疗直至P2结束（攻毒后9天）。然后对奶牛进行跟踪直至第75天（第3阶段，P3）。每天记录产奶量（MY）和干物质摄入量（DMI）。采集用于体细胞评分的牛奶样本，并在攻毒期（P2）记录直肠和乳房温度、心率和呼吸频率，同时采集血液样本用于代谢物和免疫功能分析。使用SAS中的PROC MIXED程序按阶段对数据进行分析。活检样本通过RNA测序用于转录组分析，随后进行通路分析。
在P1期，DMI和MY不受日粮影响，但在P2期记录到与时间的交互作用，表明与CON相比，NTK组奶牛从攻毒中恢复得更好。在攻毒期间，NTK降低了直肠温度、体细胞评分以及感染乳房的温度。转录组数据支持了这些发现，因为补充NTK上调了与免疫细胞抗菌功能（如CATHL4、NOS2）、上皮组织保护（如IL17C）和抗炎活性（如ATF3、BAG3、IER3、G-CSF、GRO1、ZFAND2A）相关的乳腺基因。通路分析表明，在NTK组奶牛应对乳腺炎时，肿瘤坏死因子α、热休克蛋白反应和p21相关通路上调。在NTK组奶牛中，其他解毒和细胞保护功能相关通路以及紧密连接通路也上调。
总体而言，结果突出了在亚临床乳腺炎事件中，NTK预防性补充对乳房健康保护作用所涉及的分子网络。
