In geography and fluvial geomorphology, a thalweg or talweg (/ËtÉËlvÉÉ¡/) is the line of lowest elevation within a valley or watercourse. Under international law, thalwegs can acquire special significance because disputed river borders are often deemed to run along the river's thalweg. 1 Etymology.
However, when they are 3 to 4 months old, they become susceptible to the disease, so all calves should be vaccinated for blackleg by 4 months of age. A revaccination 3 to 6 weeks later according to product label directions is necessary to provide the best protec-tion.lackleg seldom affects cattle older than 2 years of age, most likely due to immunity induced by vaccines or natural exposure. However, sporadic cases do occur in cattle older than 2 years and are often associated with the reuse of needles for multiple injections.
Primary vaccination age* 3 months or older. Booster vaccination every 3 years. Route of administration intramuscularly or subcutaneously. * Primary vaccination may be administered at an earlier age (minimum in dogs and cats of 4 weeks of age), but then a repeat vaccination must be given at the age of 3 months.Can be used during pregnancy in dogs.oute of administration intramuscularly or subcutaneously. * Primary vaccination may be administered at an earlier age (minimum in dogs and cats of 4 weeks of age), but then a repeat vaccination must be given at the age of 3 months. Can be used during pregnancy in dogs.