Racklyeft D J, Love D N
Department of Veterinary Pathology, University of Sydney, New South Wales.
Aust Vet J. 1990 Nov;67(11):402-5. doi: 10.1111/j.1751-0813.1990.tb03028.x.
Twenty four normal, confined mares were unable to lower their heads for 24 or 48 h. In 21 mares this resulted in increases in the proportion of neutrophils and/or numbers of bacteria in transtracheal aspirates. In eight mares the changes in tracheal washes were accompanied by clinical evidence of mild respiratory disease. In three additional cases respiratory signs were accompanied by systemic illness. These changes reversed once the mares were able to lower their heads. Haematological changes (absolute neutrophilia and/or hyperfibrinogenamia) were mild and occurred more commonly in horses restrained for 48 h. The results suggest that keeping the heads of healthy horses raised leads to an increased bacterial burden in their tracheobronchial secretions. These changes appeared to be related to head posture effects and not simply confinement in stocks. These findings give further weight to the theory that postural drainage may facilitate clearance of bacteria from the tracheobronchial tree. The possible relevance of such findings to post-transportation pneumonia in horses is discussed.
24匹正常的、被限制活动的母马在24小时或48小时内无法低头。在21匹母马中，这导致经气管吸出物中中性粒细胞比例和/或细菌数量增加。在8匹母马中，气管冲洗液的变化伴有轻度呼吸道疾病的临床证据。在另外3例中，呼吸道症状伴有全身性疾病。一旦母马能够低头，这些变化就会逆转。血液学变化（绝对中性粒细胞增多和/或高纤维蛋白原血症）较轻，且更常见于被限制48小时的马匹。结果表明，使健康马匹头部抬高会导致其气管支气管分泌物中的细菌负荷增加。这些变化似乎与头部姿势的影响有关，而不仅仅是被限制在畜栏中。这些发现进一步支持了体位引流可能有助于从气管支气管树清除细菌的理论。讨论了这些发现与马匹运输后肺炎的可能相关性。
