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Actinomycosis (and Actinobacillosis). —During the year, 585 animals were condemned for this disease. Many affected animals were treated by the regular dosing with potassium iodide, and a number were treated by intravenous injection. Malignant Growth. —The number of stock condemned was 196, compensation being paid in accordance with the Stock Act. Anthrax.—The position in regard to this disease is quite satisfactory, no cases arising during the year. The vaccination of stock on farms previously affected is being carried out as a precautionary measure. Blackleg.—The numbers of calves vaccinated against this disease in the affected areas were : Taranaki, 10,900 ; and Auckland, 39,320; making a total of 50,220. The Auckland district numbers show an increase of 2,923 vaccinations over last year, whereas the Taranaki figures were reduced by 5,672 when compared with the previousyear. There were 313 outbreaks in the Auckland district, compared with 302 the previous year. This involved the vaccination of 7,645 calves on 313 farms. In addition, 31,675 calves were vaccinated on 1,410 farms as a preventive measure. The diagnostic section of the Animal Research Station at Wallaceville continues to give field officers reports in cases where blackleg and malignant oedema may be confused. Johne's Disease.—A total of 94 head of stock was condemned under the Stock Act for this disease, the majority being clinical cases reported in the districts of Taranaki and the Waikato. The disease has been seen on a number of farms for the first time during the year. Apart from dealing with clinical cases as they arise on the farms, it is very difficult to control the spread of the disease, and eradication of the disease is an equally difficult problem. Non-scheduled Diseases Mastitis. —Investigations into the various problems associated with this disease are carried out by the Animal Research Division, and field advice is given by officersof the Live-stock Division. Contagious Abortion.—Vaccination of calves against this disease is now in its fourth year and the results of the first years are becoming apparent. Farmers generally are quite enthusiastic over the results obtained. The very great increase in the number of calves vaccinated in the intensive dairying districts has increased the work of field staff to a degree not visualized at the beginning. In addition to large numbers vaccinated by elub veterinarians, officers in the Wellington district vaccinated over 20,000 calves. As the numbers continue to increase from year to year in a spectacular manner, it is necessary for farmers to assist the vaccinating staff in every way possible, otherwise it will be most difficult to meet all requirements in coming seasons. As it is, sound organization and co-operation will be necessary to avoid duplication of motorrunning, and waste of valuable time could be avoided if all stock-owners provided yarding facilities and had their stock assembled for treatment. It will be realized that the expanding volume of work has to be carried out within a few weeks each season, so that the need for all assistance possible should be clear to every dairy-farmer. Departmental field officers are anxious to cover their areas as fully as possible, but if late applications are sent forward from areas already dealt with, a duplication of work is involved and possibly great difficulty in getting the work fitted in with other duties. Temporary Sterility.—This type of delayed conception in dairy cows has again been reported during the year. The trouble mainly affected individual members in herds and no serious interference with the normal breeding programme will result. Although there is some evidence of vaginitis in nearly all affected animals, it is frequently difficult to state what is the actual cause in some cases. A careful watch has been maintained for Trichomonads in herds where the breeding history would lead one to suspect this organism. Trichomoniasis is very difficult to demonstrate, but ascontagious abortion becomes controlled through vaccination it should be possible to determine whether trichomoniasis is a serious factor in the cause of abortion and subsequent sterility.

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