Opinion by
Smith, J.,It is not necessary, in disposing of this case, to determine the liability of the owner of a domestic animal for all its acts while trespassing upon another’s land. In such eases, 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. When the primary trespass is the wilful act of the owner, he may be held to a larger measure of responsibility; thus, if he take a dog into a field where he is himself a trespasser, and the dog there kills or injures sheep, this, though its first offense, may be laid as an aggravation of the trespass: Beckwith v. Shandike, Burr. 2092; Michael v. Alestree, 2 Lev. 172, cited in Dolph v. Ferris, 7 W. & S. 367. Beyond this, the authorities appear unsettled, and principle and analogy form the only guide. Doubtless there may be mischief so far independent of the primary trespass, and unrelated to the propensity or habit leading to this, that it can*5not properly be deemed matter of aggravation. In my view, however, the mischievous act, when incident to the primary trespass, in any of its aspects, or so closely associated with it as to form a substantive part or an immediate result of it, is a legitimate matter of aggravation, for which the owner should be held liable. In such case, the propensity or habit leading to the primary trespass may be regarded as the proximate cause of the resulting injury. If, for example, trespassing cattle, in order to reach the vegetation in a hot bed, break its glass covering, the owner must be held liable for this injury, though cattle are not bjr nature prone to break glass. Such breaking is incident to the primary trespass, and grows out of the propensity leading to this. If an animal injure a person lawfully trying to prevent it from trespassing, the owner should be held liable, though the injury be one which the animal is not prone to commit. In such case the mischievous act is closely associated with the primary trespass, and in fact grows directly out of it. The same principle must govern if a person be injured in trying to prevent the continuance of a trespass, or of acts forming an aggravation of it.
As was said in Rossell v. Cottom, 31 Pa. 525: “ The property in the animal raises the duty, on the part of the owner, to guard against its mischievous propensities; and failing in this, it holds him answerable for its injurious acts, without regard to the degree of care bestowed in controlling it. ‘ Sic utere tuo ut alienum non lsedas ’ applies to all such cases. It is not a question of negligence or want of due care on the part of the owner.” This principle is more in accord with the requirements of present conditions and needs of the people than the doctrine of non-liability of the owner without notice of the vicious habits of his cattle. It is reasonable to presume that an owner of cattle is better acquainted with their habits than a stranger would be, and if ignorance on this point will relieve an owner from the consequences of their mischievous acts, the burden of showing this should rest with him. By a statute passed two centuries ago domestic animals had a right to roam at will over a stranger’s land, if not adequately fenced. Yerily, a landowner, under this statute, was keeper of his neighbor’s cattle. But this statutory duty has ceased, and now the owner of cattle must restrain them or be held liable for the consequences. There is no sound *6reason for visiting upon third persons the injurious results of the acts of trespassing cattle, or for subjecting them to loss thus caused, while exempting the owners.
In this view of the principles which should govern' the determination of this case, the injury to the plaintiff must be deemed an aggravation of the trespass committed by the animal in entering the garden. This injury, indeed, is not such as a cow is ordinarily prone to commit; ajid there is no evidence that the defendant’s cow had contracted the habit of making such assaults.' Bub the act of the animal was one to which a creature of that kind is naturally disposed on being disturbed while feeding; and it was so directly associated with the primary trespass that, unless the plaintiff’s right to prevent a continuance of this be denied, there can be no ground for questioning the liability of the owner. This right cannot be controverted, for under the circumstances the act of the plaintiff is to be regarded as that of the tenant of the premises. The act of the animal by which the plaintiff was injured, so far from being independent of the primary trespass, or unrelated to it, grew directly out of the propensity in which this originated, coupled with the plaintiff’s attempt to prevent its continuance. The defendant’s fifth point was therefore properly refused. The case was submitted to the jury with suitable instructions, and their finding on the questions involved was concurred in by the trial court.
The judgment is affirmed.