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The continued use of the drug on the present satisfactory basis should increase the milking life of the dairy herds, or, in other words, less culling will be required on .account of this specific disease. On the same reasoning, dairy farmers should have a more stable basis of production, as they have less to fear from the disease. Contagious Abortion. —A very extensive programme of vaccinating heifers against contagious abortion disease is being carried out again this year. Though complete records are not available, more than 32,000 calves were vaccinated by our officers in the Taranaki west coast district. In the Auckland district applications have been received for the vaccination of 72,426 calves as compared with 67,643 last season. A total of 10,608 head were vaccinated in the Canterbury and west coast districts of the South Island. The number of vaccinations carried out in Otago and Southland has also increased. The very large number of animals being vaccinated each year places a heavy load ■on field officers in the intensive dairying districts ; many weeks of continuous work are required to cope with this problem alone. One aspect of the very general use of the vaccine in pedigree herds requires some consideration by breeders who desire to export stud animals to Australia. In several States in Australia a dual system of control of abortion disease is in operation. Many brucellosis-free herds have been established ; in fact, the State of Tasmania has almost eradicated the disease from its herds. Vaccinated animals are not likely to be introduced into disease-free herds or into disease-free districts on account of the danger of introducing the disease. Some difficulty has been experienced by a number of breeders in the last few years, and each exportation requires to be dealt with according to the conditions existing in the herd or State to which the animals are being sent. A brief explanation of this problem of export appears to be necessary. Temporary Sterility. —Reports are fairly general in their reference to the prevalence of a form of sterility in dairy herds which caused concern in many districts. The suggestion has been made that the type of delayed conception most commonly seen may be due to oestrogenic substances in clovers in spring and early summer. The general history in many herds is that conception takes place later in the season when the cattle have been grazing more mature feed. However, general delayed conception is serious in that the subsequent season's production may be seriously retarded. Grass-staggers. —Considerable numbers of dairy cows died from this disease last spring, many affected animals not responding to the treatment given. In a favourable spring with early growth of pasture the incidence of this disease takes on the nature of an epidemic in some districts. As curative treatment is not always satisfactory, every effort should be made to prevent the development of the disease. Too few farmers fully appreciate the value of feeding some good-quality hay or silage to cattle pastured on the lush spring feed. The supplementary feed acts as a balancing factor to the immature growth in the paddock. Lowered incidence of the disease in a backward spring when supplementary feeding is carried on for a longer period confirms this. Milk-fever. —Many dairy cows were affected with milk-fever last spring, but the response to modern treatment is good. Where losses occur to-day it is invariably found that the diseased condition being treated is a complication of more than one disease, whether combined with acidosis or grass-staggers. Salmonellosis.— I This disease has been recorded as affecting cattle and calves as well as sheep and pigs in some districts. The disease has been found to be fairly widespread, the causative organism, Salmonella typhi murium, having been isolated from cows, calves, and pigs in Northland. In commenting on the disease the Live-stock Superintendent, Palmerston North, states: " The cases have been sporadic. One outbreak in a herd registered for town supply caused six or seven deaths, with six carriers detected. An embargo on the use of milk from the farm was a necessary precaution taken until the carriers all proved negative to fcecal tests."

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