Deemer, J.
*2191 2 *218The petition is in two> counts. In the first it is alleged that plaintiff purchased some hogs from defendant at a public sale, and that defendant warranted them to be free from disease; that the hogs were not as warranted, but were afflicted with cholera; that three of the hogs •so purchased died of the disease; and that the sick hogs communicated the disease to other hogs of plaintiff that were theretofore sound and healthy, whereby he lost twenty more. ■ Damages were asked for the value of the hogs so lost, *219'and consequential damages resulting from the sickness and death of all the animals. The second count is to recover the same damages for false and fraudulent representations in the sale of the animals. Defendant admits the sale, but denies that the hogs were diseased when he sold them. He further pleaded contributory negligence of plaintiff in placing the animals purchased at the sale with his own healthy animals. In the ninth instruction given, the jury, the court said, in effect, that, if they found for plaintiff on the first count, there could be nO' recovery on the second, and, if they found for him on the second, there could be no recovery on the first. In the previous instruction the jury were told that the measure of damage was the same under either count. There was no error in this instruction. Joy v. Bitzer, 77 Iowa, 73 (3 L. R. A. 184). As the eight instruction is not objected to; the giving of the ninth was manifestly correct, for the two causes of action grew out of the same transaction. But, if the instruction was not technically correct, no prejudice resulted; for the jury found that plaintiff was not entitled to recover on either count. Fisk v. Railway Co., 83 Iowa, 255; Mayne v. Bank, 80 Iowa, 710.
3 II. In the eleventh instruction the court said “that if plaintiff, in taking the hogs in controversy among his own hogs, failed to use ordinary care in so doing, or negligently and carelessly permitted them to come in contact with and run with his well hogs, plaintiff cannot recover for loss by reason of the infection of his hogs from the hogs in controversy, if so infected.” This instruction is said to be erroneous because it eliminates the plaintiff’s knowledge of the diseased character of the animals purchased of defendant. We do not' think so. In order to determine the question of negligence or ordinary care, plaintiff’s knowledge was, of necessity, an essential feature, and there is nothing that inhibits’the jury from considering it. Moreover, in other *220parts of the charge plajnt-iff’s knowledge was made a material feature. In any event, the instruction was without prejudice, under the rules announced in the Fish and Moyne Cases, supra.
4 III. Plaintiff produced two veterinarians who gave evidence respecting the disease known as “hog cholera,” and who testified that the hogs plaintiff purchased were infected, with the disease at the time of his purchase. After giving the usual instruction with reference to the value of expert evidence in general, the court concluded as follows: "It may be further remarked, too, in Regard to evidence which is made up largely of mere theory and speculation, and which suggests mere probabilities, that it ought never to be allowed, to overcome clear and well-established facts, and, further, that the law recognizes expert tes timony as the lowest order of evidence.” The part italicized is objected to. That it announces the correct rule in a certain class of cases, as where the evidence relates to the genuineness of handwriting, is conceded. But it is argued that in the instant case it was erroneous. The right of the court to give cautionary instructions regarding such evidence is admitted, but it is claimed that it was error to instruct in this case that expert testimony is the lowest order of evidence. No doubt, this evidence, being merely the opinions of witnesses, should be received with caution; for it is yrell known that a witness testifying to an opinion is more likely to be mistaken than one who testifies to a fact. But, while it is to be received with caution, it is not always true that it is of little value, or the lowest order of evidence. In some cases it may be of great value, and of tire highest character. State v. Townsend, 66 Iowa, 745; Bever v. Spangler, 93 Iowa, 605. The disease among animals denominated “cholera” is so well known and established, has been the subject of so much investigation by experts, and its symptoms and effects have become so well recognized by professional veterinarians, that we think evidence given by” them. *221based on proven facts, should not be disparaged as was done in this case. As said in State v. Townsend, supra: “In view of the peculiar character of the case, we do not think that medical evidence should be regarded as the lowest order of evidence. The attempt to grade the evidence was calculated to mislead the jury and the instructions cannot be sustained.”
Some motions are submitted with the case. We need only say with reference thereto that they seem to> be without merit. Ror the error pointed out, the judgment is reversed.