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.
Early Weaning Calves. Early weaning calves will be an effective management tool for many breeders and will improve subsequent performance of the cow herd. The conventional weaning age of beef calves at 200-220 days of age (about 7 months) generally coincides with the lack of forage growth for spring-born calves.arly Weaning Calves. Early weaning calves will be an effective management tool for many breeders and will improve subsequent performance of the cow herd. The conventional weaning age of beef calves at 200-220 days of age (about 7 months) generally coincides with the lack of forage growth for spring-born calves.