Radioimmunological determination of chloramphenicol in the saliva of lactating cows

In an effort to search for noninvasive methods suitable to monitor compliance with the ban of chloramphenicol (CAP) in milkproducing animals, the pharmacokinetic behavior of this drug in bovine saliva was investigated. As revealed by studies using a radioimmunological assay, CAP appears following its intracisternal (i.c.) or subcutaneous (s.c.) administration in the saliva of lactating cows. The level of sensitivity of the method (1.5 ng CAP per g saliva) was reached 14 and 18 days after i.c. and s.c. administration, respectively. At present, the question must remain open as to whether the concentration of CAP in the saliva can serve as a reliable indicator for the enforcement of the highest permissible level set at 1 ng CAP per g of milk by German regulations. (orig.)