Aelianus [170-230 CE] (On the Characteristics of Animals, Book 4, 48): When once a bull has been provoked to anger and is threatening violence with his horns and rushing on with irresistible speed, the herdsman cannot control him, fear cannot check him, nor anything else; only a man may bring him to a halt and stay his onrush if he tie a scarf round his own right knee and face the bull. - [Scholfield translation]

Gaius Julius Solinus [3rd century CE] (De mirabilibus mundi / Polyhistor, Chapter 52.36): Indian bulls are tawny in color, and exceedingly fleet. Their hair is turned backwards, and their heads are all mouth. The hardness of their hides rejects all spears, and they are of such inexorable wildness that when captured they kill themselves from madness. - [Arwen Apps translation, 2011]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Quadrupeds 4.98-99): [Thomas includes the cow and the ox in his description of the bull]. [Quadrupeds 4.98] The bull, he says [i.e. Liber rerum], is an animal robust in strength, and among all social animals tame enough to surpass those who oppose the rest with rapacity. Several together fight most bitterly, but when alone, it easily succumbs to cowardice. When they are taken, they have their tongues stuck out, they do nothing with their teeth, but only with their horns: for there is no terror in their teeth. When they graze on the grass, they do not injure the roots, but only take what is visible on the surface. Bulls are gentler, and are made suitable for all work, and especially for the hills, if they are kept from lust by being castrated. And the older they are, the more tender their flesh, if they have been fattened. Pliny: They say that if they go to the right during the mating of the bull, males are born, but if they go to the left, females. Conception is seen at a single stroke. They give birth in the tenth month. And first the coagulated cow's milk becomes stone, and this shall be mixed with water. All the females have a finer and sharper voice than the males, especially in the genus of cows: for the cow has a coarser voice than the bull. The cattle of the herd have extraordinary compassion for their companions, as Isidore says, for each one inquires about the other, with whom it is usually yoked to the plough, and with frequent lowing testifies to the pious affection if by chance its partner is absent. As the Experimentator says, the ox has stronger and harder heart nerves than other animals; the bull, however, has more strength. The flesh of cattle is dry in comparison with that of pigs and goats, and therefore generates blood that is thick, turbid, and melancholy. However, it gives a lot of nourishment and is very strong; and this is a worse evil (because it is slowly digested except with strong wine and garlic). Bulls, if they remain many years in a partnership, will be greatly fattened. And when their death comes, they will die suddenly and will not suffer from a long illness before death. We see the same thing in the peasants [hominibus rusticis] and farmers, who were inexperienced in the pleasures and hardships experienced every day. The bull likes to drink clear water. The horns of females are harder than the horns of males. The fetus which the cow gives birth to before ten months does not live, because the hooves will not be completed. When the cows are very fertile, people say that the rainy season will follow in the winter. The bull's horns, if heated, can be bent at will. Cows get gout, and they can't be taken care of easily. Another infirmity happens to cows, and the sign of this infirmity is the decline of the ears, and they are not easily cured. And if the chest is opened when they are dead, it is evident that the corruption of the lungs was the cause. As the great Basil says, a drink of the blood of a bull is fatal. We have the ox as a helper in the labor and cultivation of the farm, and so great was the care of oxen among the ancients, that, as Pliny says, it is among the examples that a certain man had been condemned who had killed his own ox, and the penalty of exile was as if he had killed his farmer. The bull is the only animal that is urged onward by a goad. A bull's blood does not congeal quickly. But cow's milk is very thick and is not easily frozen by the cold, but water is separated from it and the residue will become thick; but it is thickened by fire. In the region of Ambardor there are cows of a large body, so that it is necessary for the milker to stand upright. They give an exceeding abundance of milk. But the dogs are also great in that country, and all the animals above the asses. Cows, on the other hand, cannot frequently suffer the intercourse of a bull, on account of the hardness of the rod: for it is very cartilaginous and sinewy. Aristotle reports in his book De animalibus that a bull of Armenia, once castrated, later mated once with a cow, and the cow conceived from the bull and gave birth. But this, he says, was not contrary to the order of nature, because before he was castrated he had seed in the rod, which after castration poured into the cow, and could very well generate, but never again, because the path of the seed in his testicles to the rod was prevented by the amputation of the testicles. And it should be noted that menses appear chiefly in cows and mares, and cease in four or five months. But this rarely happens except in warm regions, where there is a greater abundance of fluids and superfluities in animals. But the menstruation itself is sometimes carried out through the bladder in the urine; and the cow's urine is very pungent. Every animal has a thicker urine after birth. When two bulls are in a herd, they fight with each other, and the one who wins joins with the cows; and when the conqueror has been weakened by much intercourse, his rival attacks him, and with that of the vanquished he jumps upon the cows, in order to provoke him to fury. Twenty years is the age of bulls. If a man cuts the skin of a bull and blows into it and then gives it food, they will be fattened more quickly.Ambrose reports that oxen know to stay quietly in the stalls when the rain is pouring down. The same, where by natural sense they gather the change of the sky, they look outside, and beyond the manger they all stretch out their necks together to show that they want to come out. The blood of a bull does not freeze easily, and this is because of the natural heat of the blood; but it is frozen, but very weakly. The warm blood of the bull inflames the broken bones. Ox bile mixed with honey draws a thorn, either of wood or iron. [Quadrupeds 4.99] The bulls, as Solinus says, which are in India, have a brown color, dense and horrid bristles, a large head, and a crooked mouth open to the ears [said of the leucrota]. They are swift as the birds, their hair lies in the opposite direction. Their horns are as flexible as they please, either at will or in battle, and either lay them down or raise them.They also have another aid to fighting, as Aristotle says, because they throw dung very far behind them, the heat and stench of which deters dogs and hunters from approaching them [said of the bonnacon]. They are so ferocious in their wildness that they throw away their souls when they are captured in their fury. There are also others who are armed with three horns on their foreheads; these have by no means flexible hooves, but solid, like horses. - [Badke translation/paraphrase]

Bartholomaeus Anglicus [13th century CE] (Liber de proprietatibus rerum, Book18.63; 18.99): [Book 18.63] Juvenca or Juvencus, is a young Stéere or Bullocke that is able to be yoaked to draw at plough, as Isido[re] saith: or els it hath that name Juvencus, for in old time such a young Stéere was offered to Jupiter, and not a Bull, as he sayth: and is a lecherous Beast, because of youth, & is therefore overset with a strong yoke to make him easie & tame, and is pricked with a pricke, and compelled to follow even and foreright, the steps and fores of Dren. Juvenca, such a young Stéere, is ofte able to the coupling and joyning of Bulles, for in that age such a Stéere is joyned to the Bull to drawe. The young Cowe is made fat in léese and in pasture, to bée slayne of a Butcher, for divers use of mankinde. Hir flesh is more drye and more sad, than ye flesh of sucking calves, for she is longer without féeding of milk, and is more tender, and more hot and moyst than the flesh of an olde Oxe, or of an olde Cow: for yet she is néerer the age of sucking, than those that are of more age, as it sayd in Dietis. [Book 18.99] The Bull is called Taurus, & is neither roother nor gelded, as Isid[ore] saith. And Taurus is a nowne of Gréeke, & so is Bos also. And as hée sayeth, libro. 12. Bulles of Indie be red, and swifte, and cruell, & their haire is turned in contrarywise, & such a Bull bendeth his necke at his owne will, and putteth off dartes and shot with hardnesse of the backe, and is fierce, and is not overcome, and when he is tyed under a Figge trée, hée looseth and leaveth all his fiercenesse, and is sodeinelye sober and softe, as Isidore sayth libro. 17. Looke before de Ficu, in littera F. and is a proud beast and headstrong, and his most strength is in the necke, in the hornes, and in the powle. Plinius speaketh of the Bull, libro. 8. cap. 45. and saith, that the gentlenesse of the Bull is knowen by sight, & by sterne face, and ful eares, and in hornes, and in shape disposed to fighting: al his manace standeth in his fore-feet, with the which he diggeth the earth, and throweth it up among beasts. He useth specially such casting and throwing of earth, & comforteth him therewith, as he saith. And Aristotle lib. 2. saith, that the Bull hath a round liver, lyke to a mans lyver: and eateth alone before time of generation & of love, but then hée commeth into company of kine, as he saith, lib. 7. And fighteth then strongly against other. Also in codem, Bulls be fatted with grasse, hearbes, & corne, which bréedeth ventositie, & also they be fatted with Pesen & Beanes, and other such, & if thou doest cut & slit his skin, so that it areare somewhat from his flesh with blowing with a pipe, & givest him afterwarde to eate, then he fatteth, & is made fat with swéet meats, as with Figs and Grapes, and Reysons. Also lib. septimo, Bulles be in contrary manner & doing to horses: for they covet not to drinke water but it be colde and cléere. Also libr. 7. it is sayde, that Bulles doe fight for theyr Kine, and he that hath ye mastry, and is victor, leapeth on the female: and when he is faint and féeble by much dooing the déeds of generation, then he yt was overcome, commeth & fighteth with him, & he that hath the mastry leapeth on the female, as it were making joy of the mastrie. And Bulls use the worke of generation after one yere, & perchance after 8. months, as kine do. Looke within following in this same booke, de Vacca, in littera V. Bulls before that they bée gelded, be fierce and proude, but when they have lost theyr gendring stones, they be soft as females and mild, and fight not, and waxe in bodye, and fatten, and be made milde and soft with yokes of ploughs. Look within in littera V, de vitulo castrato. Also lib. 11. in fine it is saide. That Bulles have stronger sinews & strings, or brawnes, then Oxen: for in the gelding all the members of the body soften, & therfore in the hart of ye Bul oftentimes a bone is fou¯d: as in the heart of an Hart. Also Pli[nius]. li. 8. cap. 22. saith, that some Bulls be wilde, fierce, and sterne, and be more in quantitie & greatnesse then other Bulls, & more swifter, and those Bulles be red in coulour, and bléew in the eies, having theyr haire overturned, and groweth towards their eyes: & they have movable hornes & moveth them one after another in fighting. And have ridges & backes as hard as flint, so that they may not be wounded. And he hunteth all wild beasts, and may not be taken but in déepe pits and caves, & be alway fierce when they bée taken, & destroy themselves, & die for indignation. - [Batman]