FARM AND DAIRY.

Taranaki Daily News, 13 August 1919, Page 2

FARM AND DAIRY.

CONTAGIOUS ABORTION. ADDRESS BY AIR K. B. WOODS, H.It.U.C.S. Tliere was :i very good attendance of members of the Bell Block branch of the New Zealand Farmers' Union on Monday evening, whan Mr R. B. Woods, M.K.C.U.H., gave an address on contagious abortion. Sir J. S. Connett, president of the branch, In introducing the speaker, referred to the importance of the subject to dairy farmers. In opening his address, the .speaker said that his desire was that nil should gain some useful information that would help to keep in check, If not quito stamp out. this most insidious disease from the farm. There were two recognised fonfis of the disease—contagloui and accidental, and the latter should be looked on with suspicion. In the early part of the 19th century, scientists were divided as to the contagious nature of the disease, but as the result of experiments, which he enumerated, It Was clearly shown that the disease was contagious and caused by a specific microbe and bacillus, whose character he described, pointing out that its vitality was destroyed if kept for ten minutes in water at a temperature of between 58 and CI degrees centigrade. It could remain Infectious outside the animal seven months but not for a year, and drying had a very destructive effect on Its virulence, as virulent material dried with chloride of calciuai (lime) for threo days at a temperature of 37 degrees centigrade failed to infect.

He pointod out how easily the infection could be carried loiig'distances along surface drains, In manure, in the coats of animals, the clothes of "farm workers, by dogs, etc. Infected incalf cows might.bo.brought into a clean berd. Regarding the various methods of infection, he was inclined to'believe that infection through the mouth by grazing in infected pastures was the mqst . common. He did not hold that the disease was not spread by the bult, But ho played a very small part. It was an undoubted fact that cows abort twice, and even three times In succession, but It was possible that not having acquired Immunity and being on an 1 infected faym they had become re-Infected. The course of the disease was as a rule slow, the average period between infection and the act being 33 days, and the longest 2110 days. He described at some length the symptoms of the disease, some of which wero often observed in healthy cows. Sure diagnosis of the presence of the bacillus was only obtainable with the. aid of microscope, and then as a rule only after the act. No evidence had been obtained to show that natural immunity to the bacillus was possessed by any individuals of the bovine species, but there was some ground for believing that the power of acquiring immunity varied in individuals. lie was inclined to believe, that the majority at least acquired-a serviceable degree of immunity as the result of one attack, but tliere was no doubt that in practice a considerable number aborted twice and a lesser number three times. He was looking forward with great hope that a protective serum might he successfully used. After careful study of the bacillus in every phase of its life history, it was his opinion that no drug or combination of drugs In any form whatever could have any power to produce Immunity. lie was a groat believer in good food, and even medicine, to help put the animal in good condition, and Jn that way directly help nature to. rid the animal of baclllary invasion. He. did not consider a fat cow a good subject to resist invasion by this or any other bacillus. For Instance, a fat cow at time of calving was more open to attack of milk fever bacillus.

Passing from what the cow can do for her relief and what might be termed curative'treatment, ho said there was a prevalent idea that drugs such as carbolic, given internally, would euro animals affected or prevent the Infection of healthy animals, but this had been put to severe test,and failed. The evidenco of that and other drug treatment would hardly stand analysis. In the first place when animals were put under treatment It was not known whether they were infected or not, yet every one that did not abort was put down as a cure. Also many farmers in the past did not wake up to the fact that they had abortion in their herds until the second year, jnd then without any treatment nature Itself was out on the warpath conferring a certain amount of Immunity, because In practlco it. was recognised that after the third year the disease was almost entirely confined to the new animals A great deal could be done In the matter.of prevention. Various methods were at present being put into practice, some founded on physiological considerations, others on facts and dreams. These comprised: (1) Washing of external parls with the object of destroying virulent matter. The usefulness of this was lessened If the animal remained In an Infected shed, but before removal It should be washed thoroughly with disinfectant solution, such as corrosive sublimate 1 in 200, or carbolic acid 3 per cent (2) Isolation of animals if possible before the act. The importance of this could not be too much insisted in. (3) The internal administration of drugs in patent fakes. This lie had already referred to. (4) Irrigation of genital passages after abortion. For hygienic reasons he considered these ought to be cleansed once or twice dally by iniectlons of tepid anti-septic solutions, which should not be too strong, viz., 2 per cent carbolic acid or condy's fluid, made to a light wine color. The danger of a strong solution lay In the burning up of white blood cells, also the Irritation' caused the cow much unnecessary pain. Care should also be taken in the instrument used—a soft piece of rubber and an enamel funnel being preferable, (5) Removal of animals which have aborted. It was not uncommon to feed such cows for the butcher, and they had also been sold In tho open saleyard. This was unfair to the neighbors. He considered the cow should be kept for at least three months beforo being sent, to tho sole.. In his opinion, It was short-sighted to sell a cow that once aborted, as on an affected farm she was an asset for purposes of eradication far greater than now cows brought Into the herd Unless of great value chronic aborters should be fattened (6) Though he did not' consider that tlio bull played the part he was given credit for In the spread of the disease, he considered lie must be looked on as a possible spreader, and It was not a bad plan to keep a special bull for cows that had once aborted. (7) The destruction of virulent, material and things contaminated was of prime Importance, as tho natural virus might remain active for a long time outside the body, p.cfore removal tho material should bo treated with caustic lime and afterwards, soaked in paraffin and burnt or hurled in a deep bole. Burning was best. Tho boots clothes and hands of attendant should also be disinfected, (R) Some people put a goat among the. cows as a prevention, but this was absurd.

Preventive inoculation would be more and more tried In the future, and might lead to great advances In their knowledge of the complaint.

Mr Wood 3, who illustrated his address on a blackboard, was most attentively listened to, and at tho conclusion a number ,of questions wore answered, Mr Wood stressing various Important points made in the paper. There was no possible chance of infection through artificial manures. Seven to twelve months was the longest tho bacillus could infect a paddock after an animal had aborted. He stressed the necessity for taking care not to remove Infection from one farm to another. Dry lime was a splendid disinfectant. Abortion was more likely to be prevalent In Tufanakl than In a drlor climate.

At the conclusion, the chairman expressed thanke for tlio interesting address, In which a number of facts had boen placed before them of which they had no previous knowledge Mr R. F. Cornwall said that the nddresa had been given In a commonsense manner, and free of technicalities.

The lecturer was accorded a hearty vote of thanks.