what is their behaviour like?
Can be cranky during season, more distractible during heat, and are far less easily distracted at any time.
Mare
Mares are considered easier to handle than stallions. However, geldings have little to no hormone-driven behavior patterns at all, thus sometimes they are preferred to both mares and stallions. Mares have a notorious, if generally undeserved, reputation for being "marish", meaning that they can be cranky or unwilling when they come into season.

While a few mares may be somewhat more distractible or irritable when in heat, they are far less easily distracted than a stallion at any time. 
what is andalusian horse? A horse breed what are some characteristics of this horse? Stallions and geldings average at the withers and in weight; mares average what is its influence on other breeds? Stallions were crossed with local mares adding Spanish bloodlines wherever they went, especially to other European breeds. where did the first mentioned breed originate from? Iberian horses of Spain and Portugal what is the cultural view regarding them? UNANSWERABLE what is the first mentioned breed's herd behaviour? Do not live with a harem of mares and do not fight each other to the death in competition for mares. where did this aforementioned type originate? UNANSWERABLE what is the historic use of this harlem breed mentioned? Bedouin preferred them on their raids as they were quiet. what is their reproductive cycle like? The cycle is controlled by the photoperiod, the cycle first triggered when the days begin to lengthen, as it shortens, the mare returns to the anestrus period.
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Mare [SEP] Behavior
Mares are considered easier to handle than stallions. However, geldings have little to no hormone-driven behavior patterns at all, thus sometimes they are preferred to both mares and stallions. Mares have a notorious, if generally undeserved, reputation for being "marish", meaning that they can be cranky or unwilling when they come into season. While a few mares may be somewhat more distractible or irritable when in heat, they are far less easily distracted than a stallion at any time. Solid training usually minimizes hormonal behavior. For competitive purposes, mares are sometimes placed on hormone therapies, such as the drug Regumate, to help control hormonally based behavior.