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Show CONTAGIOUS ABORTION IN ! COWS. By (Dr. David Roberts. Wisconsin State Veterinarian, '06-7-8 The germs of contagious abortion may lie dormant in a herd for years and as soon as new cattle arc added to a herd, they arc liable to contract the disease of abortion. Oftentimes wherS contagious abortion has been noticed in herds and has apparently stopped, it will be noticed that heifers hei-fers in such herds arc very apt and oftentimes do abort. These arc only positive symptoms of the contagion? form of the disease. The damage brought about by the loss of calves is not the greatest by any means. The shortage of milk, the liability of other diseases afflicting afflict-ing the herd, such as tuberculosis renders contagious abortion in cattle a dangerous disease to have in the hcird when all danger and Josses arc considered. The mere fact of cows in herds where contagious abortion exists, that carry their calves full time, docs not prove that they arc not infected with the conolagious germs of abor-ion abor-ion but simply proves that their resisting re-sisting power against the germs of contagious abortion is greater than that of a cow that' is likewise afflicted afflict-ed and aborts. Cows and heifers coining in heat at irregular intervals is another symptom symp-tom of contagious abortion. A cow may conceive and carry her calf three or four months and the germs of contagious abortion may destroy the circulation between the mother and the foetus, causing the death of the foetus and in some instances tho foetus becomes mummified. The cow may carry it full time although she takes on the appearance of a barren cow and at the time the ca'f should be born the cow passes through every ev-ery appearance' of calving but owing to the fact that the foetus is ,so small that the womb cannot contract upon it to expel it, she may retain it and carry it even longer than the regular period. If an examination of such cases be made, the mummified foetus is often found cither in the womb of the cow or sometimes forced up in the pelvic cavity or vagina. This however does not often occur but I merely mention this to show the peculiarities and the freakish things that occur where herds arc afflicted with contagious abortion. I recently had the opportunity of seeing a pure bred bulF that was brought out of an infected herd when he was too young to Jjc used for ser vice an 1 lept in aTjcrfeclly hd&luiy herd until he was old enough to be brcu to the herd, lie was then used upon the herd and introduced contagious contag-ious abortion. The germs of contagious con-tagious abortion had lain dormant within this calf from tho time of birth and the moment he became old enough for breeding purposes, the germ became active and infected all cows bred to him. This same may be applied to heifers. Tho germs of contagious abortion will lie dormant dor-mant in the heifer until she becomes of a breeding age and as soqii as" she is bred they become active. She becomes infected so that same can be noticed outwardly such as in an examination of the vulva. She infects in-fects the herd bull and he in turn infects the entire herd |