This technology is good to get once it is available, as it makes cavalry even better at evading archer fire and cover distances more quickly - traits essential for both closing a gap with an enemy and scouting. Husbandry is one of the most basic cavalry technologies. Thus, researching it is a must in order to compete with cavalry from other teams and is an absolute must for cavalry-focused civilizations like the Berbers, Huns, Saracens, or Franks.
In an age dominated for centuries by knights, the breeding and provision of horses, a branch of animal husbandry, became an important skill. Knights needed heavy chargers to carry them into battle but also dependable lighter horses with stamina for campaigning in the country. Scouts and light cavalry needed fast and nimble horses when traveling cross-country in enemy territory. Horse breeders of the Middle Ages selected for these traits, and horses of different abilities were the result.
Husbandry refers to the breeding of animals for a specific purpose. Humans have been practicing husbandry for thousands of years, since the first domestication of animals. During the Middle Ages, Europe bred several different types of horses: Packhorses for endurance; light, fast horses for scouting; large and heavy horses for warfare. Husbandry has had an enormous impact on warfare: it was in part thanks to their superb husbandry that the Mongols were able to perform military feats unimagined by their European opponents; their speed and endurance often caught their opponents off guard.