Parker A J, Hamlin G P, Coleman C J, Fitzpatrick L A
Australian Institute of Tropical Veterinary and Animal Science, School of Biomedical Sciences, James Cook University, Townsville 4811, Australia.
J Anim Sci. 2003 Jun;81(6):1434-9. doi: 10.2527/2003.8161434x.
There is a lack of information pertaining to the effects of transport stress on the acid-base physiology of ruminants. The effect of transportation and/or feed and water deprivation on acid-base balance was studied using 19 2-yr-old Bos indicus steers. The steers were allocated to one of three groups: 1) control, offered ad libitum access to feed and water (n = 8); 2) water and feed deprived, offered no feed or water for 60 h (n = 6); and 3) transported, offered no feed or water for 12 h, and then transported for 48 h (n = 5). Blood gases, electrolytes, lactate, total protein, albumin, anion gap, strong ion difference, and total weak acids were determined at the conclusion of transportation. Arterial blood pH did not differ among the experimental groups. Partial pressure of carbon dioxide (pCO2) was lower for the water and feed deprived (P = 0.023) group than for the control group. Plasma total protein, albumin and total weak acid concentrations were higher for the transported (P = 0.001, P = 0.03, P = 0.01) and water- and feed-deprived (P = 0.000, P = 0.003, P = 0.001) groups, respectively, compared with the control group. Transported animals had a lower plasma concentration of potassium (P = 0.026) compared with the control animals. This study demonstrates that although blood pH remains within normal values in transported and fasted steers, the primary challenge to a transported or feed- and water-deprived animal is a mild metabolic acidosis induced by elevated plasma proteins, which may be the result of a loss of body water. The loss of electrolytes had little effect on the acid-base balance of the animals.
关于运输应激对反刍动物酸碱生理学影响的信息匮乏。本研究使用19头2岁龄的印度瘤牛阉牛，探讨运输和/或禁食禁水对酸碱平衡的影响。这些阉牛被分为三组：1）对照组，自由采食和饮水（n = 8）；2）禁食禁水组，60小时不提供饲料和水（n = 6）；3）运输组，12小时不提供饲料和水，然后运输48小时（n = 5）。运输结束时测定血气、电解质、乳酸、总蛋白、白蛋白、阴离子间隙、强离子差和总弱酸。各实验组之间动脉血pH无差异。禁食禁水组的二氧化碳分压（pCO2）低于对照组（P = 0.023）。与对照组相比，运输组（P = 0.001、P = 0.03、P = 0.01）和禁食禁水组（P = 0.000、P = 0.003、P = 0.001）的血浆总蛋白、白蛋白和总弱酸浓度分别较高。与对照动物相比，运输动物的血浆钾浓度较低（P = 0.026）。本研究表明，虽然运输和禁食阉牛的血液pH仍在正常范围内，但运输或禁食禁水动物面临的主要挑战是血浆蛋白升高引起的轻度代谢性酸中毒，这可能是机体失水的结果。电解质的丢失对动物的酸碱平衡影响很小。
