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A total of 3,466 dairy cattle were subjected to the test in herds registered for town supply and 127 reactors were found. In addition, 10,280 cattle were tested at the owner's request and 2,735 head of stock were tested at Government farms under the control of several Departments. Actinomycosis (and Actinobacillosis). —During the year 637 animals were condemned for this disease, while a large number of animals were successfully treated with iodides. The injection treatment with sodium iodide is most suitable when run cattle are found to be affected with this disease, regular dosing being impracticable. Malignant Growth. —The number of stock condemned was 218, a decrease of 12 on the figure recorded the previous year. Compensation was paid in accordance with the Stock Act. Johne's Disease.—A. total of 207 animals were condemned for this disease under the Stock Act, the majority being in the Taranaki district. As has been found in other countries, the control of this disease is very difficult. Inquiries have been made with a, view to trying out vaccination of young calves on farms where the incidence would warrant such a procedure. Anthrax. —No cases of this disease occurred during the year. Because of protective vaccination, the stock on previously infected farms have remained healthy. Blackleg.—The numbers of calves vaccinated against this disease in the affected areas were : Taranaki, 24,000, and Auckland, 36,646 ; making a total of 60,646. Compared with the previous year, the number of calves vaccinated increased by 4,511 in Taranaki and by 5,615 in Auckland. There were 280 outbreaks in the Auckland district, compared with 334 the previous year. This involved the vaccination of 6,491 calves on 280 farms. In addition, 30,155 calves were vaccinated on 954 farms as a preventive measure. Non-scheduled Diseases Mastitis. —Many aspects of the mastitis problem are being investigated by the Animal Research Division. Field officers of the Live-stock Division are co-operating with the research officers on the work being carried out with penicillin. The prospects of good results being obtained with penicillin in the treatment of affected animals should prove satisfactory to the dairy-farmer, but there should be no relaxation of effort in regard to dairy hygiene in the shed in an attempt to reduce the incidence of the disease in dairy herds by preventive methods. Contagious Abortion.—The vaccination of dairy heifer calves against this disease is an accepted practice, and the programme of vaccination work in the intensive dairying districts is now heavy. In the Wellington district field officers vaccinated about 20,000 calves last year. The work was also very heavy in many parts of the Auckland district, the assistance given by club veterinarians being very valuable. The irregular supply of vaccine from Australia has caused many delays and has upset the arrangement of vaccination itineraries by many officers. Vaccination against the disease is also being carried out in many parts of the South Island. Temporary Sterility.—Each season field officers are called on to advise farmers about breeding troubles in the dairy herds. Delayed conception in cows, with return of heat periods, is the most common form of complaint. The intensive seasonal nature of dairy-farm production makes such a problem of vital importance to the subsequent season. Otherwise it is felt that the majority of affected animals recover without any special treatment, the enforced delay in breeding being all that is required. Each instance requires to be investigated so that, if male infertility is the cause, it can be rectified as soon as possible.

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