评估从干奶到产犊的体况评分动态对荷斯坦奶牛泌乳早期疾病发病率的影响  

Assessing the Impact of Body Condition Score Dynamics from Dryoff to Calving on the Incidence of Early Lactation Disease in Holstein Cows

作　　者：李胜楠(编译) 郭凯军[1] LI Shengnan;GUO Kaijun(Beijing University of Agriculture,Beijing 100096)

机构地区：[1]北京农学院,北京100096

出　　处：《中国乳业》2024年第11期69-73,共5页China Dairy

基　　金：北京市家畜创新团队项目(BAIC05-2024)。

摘　　要：[目的]通过图像技术自动生成体况评分(BCS)的系统能够以高效且无应激的方式对奶牛的体能储备进行每日评估,并生成客观信息。高频BCS数据可用于分析特定的关注点,并在必要时快速调整饲养管理方式。本研究的目的是评估高产荷斯坦奶牛群体从干奶到产犊时的BCS动态与泌乳早期疾病之间的关联。使用2019年4月—2022年1月在美国科罗拉多州一家商业奶牛场产犊的7626头荷斯坦牛的12042次泌乳中收集的数据完成回顾性观察性研究。[方法]选择干奶(BCSdry)和产犊(BCScalv)奶牛由BCS相机(DeLavalInternationalAB,瑞典Tumba)生成间隔0.1的评分,随后分别针对初产牛和经产牛进行四分位数分类(Q1=最低BCS)。从干奶时到产犊时的BCS变化计算为BCScalv-BCSdry,并分配到四分位数类别,其中Q1被视为损失最大的25%的奶牛。奶牛被归类为健康(HLT;无健康事件)或产后60天内至少受一种健康疾病影响(SCK)。健康问题包括繁殖问题(胎衣不下、子宫炎和子宫囊肿),代谢问题(临床低钙血症、亚临床酮病和左侧真胃移位)和其他问题(跛行、临床乳房炎、消化问题、受伤和肺炎)。[结果]HLT与SCK之间的平均(SE)BCSdry为3.38(0.004)与3.42(0.004)(P<0.0001),而BCScalv为3.30(0.003)与3.33(0.003)(P<0.0001)。HLT与SCK之间的平均BCS在干奶时和产犊时之间的差异为-0.088(0.004)与-0.11(0.005)(P=0.008)。逻辑回归分析表明,相对于BCS值最高的类别(Q4),BCS值较低的干奶牛患病几率(95%CI)较低:Q1=0.78(0.65~0.94);Q2=0.75(0.62~0.90);Q3=0.79(0.65~0.96)。相反,BCScalv类别与泌乳早期疾病无关(P=0.48)。从干奶时到产犊时BCS降低与随后的疾病有关,BCS上升的奶牛(Q4)相比,BCS下降较多(Q1和Q2)的奶牛患病几率更高:Q1=1.32(1.11~1.58)和Q2=1.35(1.14~1.61)。[结论]干奶时BCS以及干奶时至产犊时BCS的显著下降对早期泌乳期疾病的发生有显著影响。[Objective]Automated systems generating body condition scores(BCS)through image technology enable daily assessments of body energy reserves of dairy cows in an efficient non stressful approach and generate objective information.The availability of high-frequency BCS data allows for the analysis of specific points of interest and could result in quick adjustments of management if necessary.The objective of this study was to evaluate the association between the dynamics of BCS from dry-off to calving and early lactation disease in a population of high-producing Holstein cows.[Method]A retrospective observational study was completed using data collected from 12042 lactations in 7626 Holstein cows calving between April 2019 and January 2022 in a commercial dairy operation located in Colorado,USA.Scores generated by BCS cameras(DeLaval International AB,Tumba,Sweden),at 0.1 point intervals,at dry-off(BCSdry)and calving(BCScalv)were selected for the analysis and subsequently categorized into quartiles(Q1=lowest BCS),separately for primiparous and multiparous cows.The change in BCS from dry-ff to calving was calculated as BCScalv–BCSdry and assigned into quartile categories considering Q1 as the 25%of cows with greatest loss.Cows were classified as healthy(HLT;no health event)or affected by at least one health disorder within 60 days postpartum(SCK).Health disorders included reproductive(retained fetal membranes,metritis,and pyometra),metabolic(clinical hypocalcemia,subclinical ketosis,and left displaced abomasum),and other conditions(lameness,clinical mastitis,digestive problem,injury,and pneumonia).[Result]Mean(SE)BCSdry for HLT vs.SCK were 3.38(0.004)vs.3.42(0.004)(P<0.0001),while BCScalv for HLT vs.SCK were 3.30(0.003)vs.3.33(0.003)(P<0.0001).Mean BCS differences between dry-off and calving for HLT vs.SCK were-0.088(0.004)vs.-0.11(0.005)(P=0.0008).The logistic regression analyses indicated that the odds(95%CI)of disease were smaller in the lower BCSdry categories relative to cows in the highest BCS category(Q4):Q1=

关 键 词：体况评分 自动化 健康 

分 类 号：S858.23[农业科学—临床兽医学]