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Pleukisy in Pigs. The amount of condemnation from pleurisy in pigs for export led to the examination of a number of lungs from recent and from chronic cases of pleurisy. Material was forwarded from various meat-works. Two hundred and four specimens were cultured and the type of lung lesion beneath the pleural adhesion was noted. In cases of solidification with pus in the bronchus, pasteurella was commonly obtained. B. pyogenes was found in the larger walled-off abscesses. Congested lungs frequently gave a pure culture of Salmonella suipestifer but often Streptococcus were also present. In oldstanding cases where the lung appeared fairly normal except for the pleural adhesion Streptococcus were commonly found present. The general belief was that Salmonella suipestifer set up an acute congestion of the lung which was followed by Streptococcus and B. pyogenes. Pasteurella itself could also set up consolidation without prior lung injury. Mottled Kidneys. Mottled Kidneys received in numbers from meat-works have not yielded anything specific by cultural methods. The lesion, when found in the works is apparently of some considerable standing even though the kidney is showing localized hemorrhagic areas only. Apparently the condition resembles white spotted kidney of young calves due to B. coli for the final appearance is a multiple localized interstitial nephritis. POULTRY DISEASES. In general, diseases in poultry are becoming more common. Those requiring urgent attention are coccidiosis of birds of 5 to 7 months of age, leukaemia in young birds and to some extent, fowl-pox and roup. Coccidiosis. The greatest danger is the spread of the coccidiosis by sale of infected young stock. Considerable work is required concerning the methods of carriage and the best method of control, but with the limited staff there is no possibility of this at present. LETJKiEMIA. Leukaemia is occurring on a number of poultry-plants. It crops up in a flock of young birds less than one year old, killing a few, and then seems to appear only at infrequent intervals in after years in odd birds. The condition cannot be reproduced by inoculation of filtrates nor of actual cells. Cultural work on a number has yielded in five of the cases, three enteritidis cultures and two pullorum. Mr. W. M. Webster before leaving the Division carried out intravenous inoculation of a number of cockerels daily for some weeks with various organisms of the Salmonella group, and was able to produce a condition very similar to some of the cases of leukaemia received from the field, thus bearing out American work on the subject. No cases of transmissible leukemia have yet been noted. Fowl-pox. Fowl-pox vaccination has been advocated where necessary following trial with Australian vaccine. It is proposed later to make fowl-pox vaccine at this station. Distempbb in Dogs. An experimental vaccination of puppies with vaccine virus sent to New Zealand by Burroughs, Wellcome, and Company by air-mail proved only partially successful. The reasons for this failure were either that the virus had died en route through the tropics or that the puppies used for the experiment accidentally contracted distemper in a mild form before vaccination. The former reason is believed to be the true one for control pups inoculated with virus did not become infected. Material which was to have been supplied by the Australian Commonwealth Serum Laboratories was not available. FARM. The usual activities on the farm have been carried on with some difficulty owing to the illness of the Farm Overseer, Mr. J. Evans. Haymaking was long drawn-out by reason of heavy crops, lack of men, and lack of horses. However, considerable quantities of silage, hay, roots, and green maize and oats were obtained. Paddock 5, the last of the paddocks to be brought under the plough, has been sown in permanent pasture. NUTRITIONAL RESEARCH WORK PERFORMED BY Dβ. I. J. CUNNINGHAM. Dr. Cunningham supplies the following sub-report : — During the year work has continued on grass staggers and magnesium metabolism, on the relation between dietary protein and sterility, on the toxicity of common smuts, and on vitamins. Geass Staggeks in Daiky Cows. Preventive treatment. —Experiments were arranged in collaboration with Mr. D. Marshall, M.R.C.V.S., for supplementary feeding of dolomite on four farms where grass staggers occurs very regularly. The dolomite was incorporated in the silage or sprinkled on hay as it was fed out. Results were complicated by an unusually good season—grass being so plentiful that little hay or silage was employed. Consequently, the expected quantities of dolomite were not consumed by the cows before the period of their susceptibility to grass staggers had arrived. In spite of these difficulties the results of the experiments offered some degree of hope. Of the four farms, one had no cases of grass staggers, the second had one mild case which recovered on treatment with Epsom salts, the third had two cases of which one recovered spontaneously, while the fourth had three cases. On the last farm the affected cows had had no dolomite-treated feeding-stuff. More extensive experiments have been arranged for the coming year. Five tons of dolomite have been purchased by the Department, and this material has been distributed by Mr. Marshall to about twelve farmers. Grass Staggers and Magnesium Deficiency. —An investigation has been concluded into the question whether grass staggers is due to a deficiency of magnesium in the food. The following lines of work have been carried out: — (a) The determination of the magnesium content of pasture samples, taken regularly throughout the year, from plots on farms where grass staggers has frequently occurred. Also the examination of hay and silage samples for magnesium content.

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