Department of Population Medicine, University of Guelph, Ontario, Canada N1G 2W1.
Department of Population Medicine, University of Guelph, Ontario, Canada N1G 2W1.
J Dairy Sci. 2022 Mar;105(3):2544-2557. doi: 10.3168/jds.2021-21046. Epub 2021 Dec 23.
Nonambulatory dairy cattle pose a complex problem due to the challenges associated with prevention, appropriate treatment and management, and arriving at an accurate prognosis. There is a breadth of literature regarding this topic, of which there is currently no formal synthesis. The objective of this scoping review was to describe and characterize the literature investigating risk factors, sequela, preventions, treatments, and prognostic factors for nonambulatory conditions in dairy cattle, with the intent of qualitatively synthesizing knowledge of the topic and identifying gaps in the literature. A literature search was conducted in 6 databases and 2 conference proceeding archives, which returned 7,568 unique articles. Initial screening of abstracts resulted in 1,544 articles reviewed at the full-text stage, of which 379 were included for data extraction. Over 75% of the included literature was published after 1980, and the most common countries in which these studies took place were the United States (n = 72), Canada (18), Sweden (17), and Germany (17). Common eligibility criteria used for inclusion were geographic region (97) and parity (92). Of the 379 studies included in this review, 144 were randomized controlled trials and 235 were observational studies. The majority of the controlled trials assessed prevention of nonambulatory conditions (116), most commonly through supplementation of vitamin D (27) and calcium (25) or the provision of anionic salts (22). Of the 28 studies focusing on treatment of nonambulatory conditions, 26 focused on calcium administration. Becoming nonambulatory was evaluated as an outcome in 165 of the observational studies. Frequently measured risk factors for becoming nonambulatory included hematological variables, such as blood calcium (73), phosphorus (53) and magnesium (42), and other factors such as parity (35) and breed (22). Recovery from a nonambulatory condition was the outcome in 31 of the observational studies, with commonly measured prognostic indicators being calcium (9), phosphorus (9), and duration of recumbency (7). Nonambulatory disorders were measured as risk factors in 53 of the observational studies, with the most commonly assessed outcomes including disorders of the transition period (11), and death or euthanasia (11). The most common terms used to describe nonambulatory conditions were "milk fever" (199) and "parturient paresis" (147). These terms were only further defined with explicit symptomatic criteria in 193 of the 379 studies in this review. Recumbency was the most commonly used of these criteria (144), followed by inability to rise (55). Potential gaps in the literature concerning nonambulatory dairy cattle that were identified in the present review included investigation of prognostic indicators for recovery from nonambulatory conditions that are applicable on farm, treatment alternatives to calcium administration, and guidance regarding the appropriate usage of terms meant to categorize nonambulatory dairy cattle.
非卧床奶牛由于与预防、适当治疗和管理以及准确预后相关的挑战而构成复杂的问题。关于这个主题有大量的文献，但目前没有正式的综合。本范围综述的目的是描述和描述调查奶牛非卧床条件的风险因素、后遗症、预防、治疗和预后因素的文献，旨在定性综合该主题的知识并确定文献中的空白。在 6 个数据库和 2 个会议论文集档案中进行了文献检索，共返回 7568 篇独特的文章。对摘要进行初步筛选后，有 1544 篇文章在全文阶段进行了审查，其中 379 篇文章进行了数据提取。纳入的文献中超过 75%是在 1980 年后发表的，这些研究最常见的国家是美国（n=72）、加拿大（18）、瑞典（17）和德国（17）。纳入标准中常见的纳入标准是地理区域（97）和胎次（92）。在本综述中纳入的 379 项研究中，有 144 项为随机对照试验，235 项为观察性研究。大多数对照试验评估了非卧床条件的预防（116），最常见的方法是补充维生素 D（27）和钙（25）或提供阴离子盐（22）。在 28 项关注非卧床条件治疗的研究中，有 26 项研究侧重于钙的管理。在 165 项观察性研究中，非卧床状态评估为结局。常见的非卧床风险因素包括血液学变量，如血钙（73）、血磷（53）和血镁（42），以及其他因素，如胎次（35）和品种（22）。在 31 项观察性研究中，非卧床状态的恢复是结局，常用的预后指标为钙（9）、磷（9）和卧床时间（7）。非卧床疾病在 53 项观察性研究中被评估为风险因素，最常评估的结局包括过渡期疾病（11）和死亡或安乐死（11）。用于描述非卧床疾病的最常见术语是“产褥热”（199）和“分娩瘫痪”（147）。在本综述中纳入的 379 项研究中，只有 193 项进一步明确了这些术语的明确症状标准。卧床是这些标准中最常用的（144），其次是无法起床（55）。在本综述中确定的与非卧床奶牛有关的文献中的潜在空白包括调查适用于农场的非卧床疾病恢复的预后指标、钙管理以外的替代治疗方法以及关于用于分类非卧床奶牛的术语的适当使用的指南。
