Morantel could not be detected (< 0.05 microgram/ml) in the plasma of cattle or goats following the
oral administration of
morantel tartrate at a dose rate of 10 mg/kg bodyweight. No
morantel was detected in the milk of lactating goats except in one animal where a concentration of 0.092 microgram/ml was detected at 8 h after
drug administration.
Morantel was highly effective against Cooperia oncophora
infections in calves treated 6, 9 or 18 days after
infection; however, was highly effective against Ostertagia ostertagi only when treated 18 days after
infection.
Morantel did not affect the fecundity of adult O. ostertagi surviving treatment 18 days after
infection which had similar average numbers of eggs in their uteri (range 13.4 +/- 0.73-16.8 +/- 0.98) as did parasites from control animals (range 12.0 +/- 0.70-13.6 +/- 0.66).
Morantel could be detected at a concentration of 96 +/- 4.5 micrograms/g (dry weight) in the faeces of a calf 24 h
after treatment with 10 mg/kg bodyweight of
morantel tartrate. The concentration of
morantel in replicate samples of this faeces exposed to natural atmosphere, but not to soil or soil organisms, declined slowly over the following 322 days. At day 322 after the start of the experiment 8.8 micrograms/g of
morantel could be measured in the remaining faecal material. Throughout the faecal degradation study the concentration of
morantel in the crusts of the replicate sample pats was lower than the concentration in the core samples.