Van Schyndel S J, Bogado Pascottini O, LeBlanc S J
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Ont., N1G 2W1, Canada.
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Ont., N1G 2W1, Canada.
Theriogenology. 2018 Oct 15;120:117-122. doi: 10.1016/j.theriogenology.2018.08.001. Epub 2018 Aug 9.
A limited number of cow-side diagnostic techniques exist for the diagnosis of subclinical endometritis (SCE) in dairy cattle. The objectives of this study were to compare results of endometrial cytology from samples collected by cytobrush (CB) and low-volume lavage (LVL) and to assess leukocyte esterase (LE) test strips and Brix refractometry as surrogate cow-side tests for SCE. Two samples were consecutively collected from 248 Holstein cows between 29 and 35 days postpartum, using CB and LVL techniques. Each sample was analyzed using cytology with a cut-point of ≥5% polymorphonuclear (PMN) cells, LE strips using cut-points of ≥1 and ≥ 2, and a Brix refractometer. Each diagnostic technique was compared intra-sample using the respective cytology as a gold standard and inter-sample using CB samples as the referent. The concordance correlation coefficient (CCC, ρ) for PMN% between CB and LVL was ρ = 0.59 [95% confidence interval (CI): 0.50 to 0.67] and the Kappa (κ) for agreement was κ = 0.35 [sensitivity (Se) = 0.88, specificity (Sp) = 0.45]. The optimal cut-point of LE ≥ 2 resulted in moderate agreement between CB and LVL samples, κ = 0.56 (Se = 0.89, Sp = 0.65). Agreement between LE and cytology using CB (κ = 0.49; Se = 0.89, Sp = 0.57) and LVL (κ = 0.44; Se = 0.77, Sp = 0.67) were similar. The correlation between Brix values from CB and LVL was ρ = 0.12 (CI -0.01 to 0.26). The correlation between CB cytology and Brix was ρ = 0.33 (CI 0.20 to 0.45) but ρ = -0.07 (CI -0.21 to 0.06) between LVL cytology and Brix. While LE strips with a cut-point of LE ≥ 2 had moderate agreement with cytology, Brix refractometry had poor performance for the diagnosis of SCE. Samples taken by CB and LVL produced comparable cow-side diagnostic results and either is a viable method for the diagnosis of SCE.
目前用于诊断奶牛亚临床子宫内膜炎（SCE）的牛场现场诊断技术数量有限。本研究的目的是比较通过细胞刷（CB）和低容量灌洗（LVL）采集的样本的子宫内膜细胞学结果，并评估白细胞酯酶（LE）试纸条和糖度折射计作为SCE的替代牛场现场检测方法。在产后29至35天期间，使用CB和LVL技术从248头荷斯坦奶牛中连续采集两个样本。每个样本使用细胞学法进行分析，以多形核（PMN）细胞≥5%为切点，LE试纸条以≥1和≥2为切点，以及使用糖度折射计进行分析。每种诊断技术在样本内以各自的细胞学作为金标准进行比较，在样本间以CB样本作为参照进行比较。CB和LVL之间PMN%的一致性相关系数（CCC，ρ）为ρ = 0.59 [95%置信区间（CI）：0.50至0.67]，一致性的Kappa（κ）为κ = 0.35 [敏感性（Se）= 0.88，特异性（Sp）= 0.45]。LE≥2的最佳切点导致CB和LVL样本之间具有中等一致性，κ = 0.56（Se = 0.89，Sp = 0.65）。使用CB（κ = 0.49；Se = 0.89，Sp = 0.57）和LVL（κ = 0.44；Se = 0.77，Sp = 0.67）时，LE与细胞学之间的一致性相似。CB和LVL的糖度值之间的相关性为ρ = 0.12（CI -0.01至0.26）。CB细胞学与糖度之间的相关性为ρ = 0.33（CI 0.20至0.45），但LVL细胞学与糖度之间的相关性为ρ = -0.07（CI -0.21至0.06）。虽然切点为LE≥2的LE试纸条与细胞学具有中等一致性，但糖度折射计对SCE的诊断性能较差。通过CB和LVL采集的样本产生了可比的牛场现场诊断结果，两者都是诊断SCE的可行方法。
