Opinion by

The plaintiff and the defendant each owned a boar pig. One evening the defendant’s boar broke into plaintiff’s barnyard and killed his boar. Suit is brought for its value. Three propositions were submitted by the court to the jury in the following language: (1) Was the animal vicious and did the owner know it? (2) Was the animal at the time of the injury in the control, ownership and possession of the defendant? (3) Did the owner permit the animal to run at large? All of these were questions of fact for the jury and under the instructions of the court any one of these propositions answered in the negative would necessarily result in a verdict for the defendant. As to the first proposition, we think the court was in error in stating that under the circumstances in this case, to hold the defendant the jury must find that the animal was vicious and the owner knew it. “On account of the natural and notorious propensities of horses, cows, and sheep to rove, the owner is bound, at all hazards, to confine them on his own land, and if they escape and do any mischief on the land of another, which they are naturally inclined to commit, the owner is liable to an action of trespass, although he had no notice in fact of such propensity”: Dolph v. Ferris, 7 W. & S. 367. In Troth v. Wills, 8 Pa. Superior Ct. 1, this court held, following a number of *353cases, that the owner of a trespassing animal is liable for such damages as naturally follow. We quote from the opinion, “The primary trespass is the entry of the animal upon the land; the attendant damage for which the owner may be held liable is matter of aggravation. The minimum liability of the owner is for acts arising from the natural propensities of the species, and from special characteristics and acquired habits of the individual of which the owner has notice.” In that case a cow trespassed upon another’s land and hooked the plaintiff who endeavored to drive it off. See Ramsey v. Martin, 45 Pa. Superior Ct. 645.

We all know that the males of certain species of animals will almost invariably attack each other, and it was not an essential part of plaintiff’s case to prove that the boar of defendant was of vicious disposition and that the owner knew it; the question should have been submitted to the jury whether the owner, if he allowed such an animal to be at large, was not chargeable with the knowledge that naturally if he were to meet another boar he would be liable to inflict injury. The learned judge, in considering the question whether the case was properly brought before a justice of the peace, commenting on the cases above cited and a number of others, concludes that branch of his opinion in these words, “I am, therefore, of the opinion that, from the trend of these authorities, an action of trespass may be maintained before a justice, where a hog escapes from the owner’s property or from his control on a public road, or is permitted to run at large, and it enters the premises of another and causes damage. If, then, this was all that appeared in the presen]; case, the plaintiff would be entitled to a verdict. It, however, was not the crucial point raised on the trial, and it becomes necessary to turn to the uncontradicted facts as established by the verdict.” He then states that the two questions had been submitted to the jury,- (1) whether the hog was at the time the killing occurred in possession and under *354control of the defendant? and (2) whether at the time of the killing the hog belonged to defendant or some one else? The court here inadvertently fell into error. As we stated before three questions were submitted and the jury was definitely instructed as to one of them in order that he (the plaintiff) might recover, the jury must conclude not only that the hog was vicious, but as we have said that defendant knew it. Of the three questions categorically submitted this was the first. Having found for the defendant generally we cannot tell whether the verdict was premised upon the lack of proof of viciousness in the animal or upon one or other of the remaining questions. If the jury found that the animal was not vicious it was relieved under the instructions given from any consideration of the other questions. We cannot therefore say that this was “not the crucial point raised on the trial” quoting the words of the learned trial judge, when it is submitted to the jury with the language, “You must find that the hog was vicious and the owner knew it.” Nor can we sustain the judgment on the theory that there should have been binding instructions for the defendant. Having admittedly been the owner of the boar on the day preceding the trespass, the jury had to determine as to the truth of his story that he had parted with his possession to one man and his ownership to another. The case must go back for retrial.

The first and second assignments of error are sustained. The judgment is reversed with a venire facias de novo.