Effect of host genotype and Eimeria acervulina infection on the metabolome of meat-type chickens

ObjectiveA study was conducted to identify metabolic biochemical differences between two chicken genotypes infected with Eimeria acervulina and to ascertain the underlying mechanisms for these metabolic alterations and to further delineate genotype-specific effects during merozoite formation and oocyst shedding.MethodsFourteen day old chicks of an unimproved (ACRB) and improved (COBB) genotype were orally infected with 2.5 x 105 sporulated E. acervulina oocysts. At 4 and 6 day-post infection, 5 birds from each treatment group and their controls were bled for serum. Global metabolomic profiles were assessed using ultra performance liquid chromatography/tandem mass spectrometry (metabolon, Inc.,). Statistical analyses were based on analysis of variance to identify which biochemicals differed significantly between experimental groups. Pathway enrichment analysis was conducted to identify significant pathways associated with response to E. acervulina infection.ResultsA total of 752 metabolites were identified across genotype, treatment and time post infection. Altered fatty acid (FA) metabolism and β-oxidation were identified as dominant metabolic signatures associated with E. acervulina infection. Key metabolite changes in FA metabolism included stearoylcarnitine, palmitoylcarnitine and linoleoylcarnitine. The infection induced changes in nucleotide metabolism and elicited inflammatory reaction as evidenced by changes in thromboxane B2, 12-HHTrE and itaconate.ConclusionsSerum metabolome of two chicken genotypes infected with E. acervulina demonstrated significant changes that were treatment-, time post-infection- and genotype-dependent. Distinct metabolic signatures were identified in fatty acid, nucleotide, inflammation and oxidative stress biochemicals. Significant microbial associated product alterations are likely to be associated with malabsorption of nutrients during infection.

研究目的：本研究旨在明确两种感染堆型艾美耳球虫（Eimeria acervulina）的鸡基因型之间的代谢生化差异，阐明此类代谢改变的潜在机制，并进一步刻画裂殖子形成与卵囊排出阶段的基因型特异性效应。研究方法：选取14日龄的未改良型（ACRB）与改良型（COBB）两种基因型雏鸡，经口接种2.5×10^5个已孢子化的堆型艾美耳球虫卵囊。于感染后第4天和第6天，从各感染组及其对照组中各取5只雏鸡采血分离血清。采用超高效液相色谱-串联质谱法（metabolon, Inc.）检测血清的全局代谢组学特征。统计分析采用方差分析，以筛选实验组间存在显著差异的生化物质；并通过通路富集分析，鉴定与堆型艾美耳球虫感染应答相关的显著富集通路。研究结果：本研究共鉴定到752种代谢物，其表达水平受鸡基因型、感染处理及感染后时间的影响。与堆型艾美耳球虫感染相关的核心代谢特征为脂肪酸（FA）代谢与β-氧化的异常改变。脂肪酸代谢中的关键代谢物变化包括硬脂酰肉碱、棕榈酰肉碱与亚油酰肉碱。感染还可诱导核苷酸代谢改变，并引发炎症反应，具体表现为血栓烷B2、12-HHTrE及衣康酸水平的变化。研究结论：两种感染堆型艾美耳球虫的鸡基因型的血清代谢组均发生显著变化，且该变化受感染处理、感染后时间及鸡基因型的调控。本研究鉴定到脂肪酸、核苷酸、炎症及氧化应激相关生化物质的特异性代谢特征。感染过程中显著的微生物相关代谢产物变化，可能与感染期间的营养物质吸收不良存在关联。