Leeches which suck blood of cattle are sometimes taken up by the animals when drinking water from ponds, etc. The leeches attach themselves to the inner surface of the mouth or nose, and sometimes reach the upper part of windpipe or the gullet. Bleeding at the mouth or nose may be noticed, the membranes where the leeches attach themselves become congested and swollen, and as a result of the loss of blood anemic condition follows.

Treatment.—If the leeches can be reached, they are easily destroyed by cutting them in two with a pair of scissors or they may be removed with a pair of forceps or with the fingers after wrapping a piece of cloth around them so as to prevent slipping.

Steam from boiling hot water containing Pine Tar or Oil or Turpentine may cause leeches to release their hold if they cannot be removed by other means. In ponds where leeches are numerous, eels should be introduced as they feed upon blood suckers of this species.