Ferula communis variety brevifolia intoxication of sheep: A study of the coagulopathy

• Main Author: Tligui, Noursaid
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-1992
• Subjects: Animal Diseases
• ISBN: 9798207501284

In the first part of this study a total of 6 sheep were intoxicated with a standardized dose of Ferula communis var brevifolia (FCb) (2.5gm powder/kg body weight/day for 15 days). The purpose of this was to study the pathogenesis of the coagulopathy induced by the consumption of this toxic plant through evaluation of the clinical signs of the illness, the activity of the coagulation factors, platelet function, hematologic changes and liver function. The coagulopathy caused by FCb was found to be related to decreased activity of the vitamin K-dependent coagulation factors: II, VII, IX and X. No significant activity decrease was observed in the coagulation factors which are vitamin K-independent: V, VIII, XI and XII. Also, there was no evidence of primary liver damage or platelet malfunction. Two of the six intoxicated sheep died respectively on days 9 and 12, with only minimal evidence of hemorrhage. The main objectives of the second part of the study were to measure the changes in concentration of ferulenol, a 4-hydroxycoumarinic compound of FCb, in 4 sheep intoxicated with FCb (2.5g powder/kg body weight, 8 times at 6 hours intervals) and to correlate those concentrations with the changes of activity of vitamin K-dependent clotting factors, the prothrombin time and the activated partial thromboplastin time. A procedure developed to extract and quantify a variety of coumarinic rodenticides in blood serum (Chalermchaikit et al., 1992), was effective for the measurement of ferulenol in plasma. The maximal plasma levels of ferulenol obtained and the time for plasma clearance varied with the individual animals. Consistent with this, the return to normal of the decreased vitamin K-dependent coagulation factors, and consequently the prothrombin time (PT) and activated partial thromboplastin time (APTT) was quicker in animals with the short time of plasma ferulenol clearance. Also, maximal PT and APTT ratios were animal dependent but not always consistent with plasma ferulenol levels. In summary, the coagulopathy induced by the toxic plant FCb was due to decreased activity of the vitamin K-dependent coagulation factors: II, VII, IX and X.