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rate dropped and deaths ceased as quickly as they started or continued at a low level for several weeks. For instance, losses on one farm started in March, 1949, and deaths •continued, apparently from Salmonella typhi murium infection, until the following June. Deaths were so sudden that some farmers never saw a sick sheep, but most noticed affected animals sick, disinterested, and tucked up for a short period before death. They usually scoured profusely or passed small quantities of very mucoid dung, light green in •colour, which had a fetid smell and sometimes contained flecks of blood, Early in an •outbreak sick sheep rarely lasted longer than twenty-four hours, but later death was •delayed for two to three days and some recovered after showing all the inital symptoms of those which died. The influence of sheep husbandry practices on Salmonellosis is obscure. In December and January mustering is frequent for shearing, drafting fat lambs, weaning others, and dipping and culling the ewes. In addition, some farmers concentrate their breeding■ewes in small paddocks after culling to bring them down in condition for tupping, but there is no clear-cut relationship between these practices and either the onset or the course of Salmonellosis in affected flocks. Foot-rot. —Foot-rot was eliminated from the Manutuke Research Station in January, 1947, and no other cases occurred until June, 1948, when the disease was reintroduced. It was again eliminated in January, 1949, and there has been no recurrence of the disease. This freedom from foot-rot at Manutuke has been maintained in spite of the introduction of several new lots of sheep with from 10 to 25 per cent, of foot-rot. Strict quarantine procedures were adopted in each case and no sheep was allowed into the paddocks until its feet had been inspected and pronounced completely free from foot-rot. Foot-rot has now also been eliminated from the Wallaceville Animal Research Station. There is no •doubt that any farmer who has sheep-proof fences can eradicate foot-rot from his property. Extreme care and a good deal of hard work are involved, but the improvement in condition and production of the sheep and the elimination of continuous foot-rot treatment would make the effort well worth while. Post-dipping Lameness in Sheep. —Following the proof that post-dipping lameness as it occurred in New Zealand in recent years was due mainly to a localized infection with Erysipelothrix rhisopathiae and that it could be controlled by the addition of bacteriostatic substances to the dipping-baths, good control of the infection has been achieved. No cases were reported in the 1949 season in which Erysipelothrix was involved, although there were a number of instances in which other organisms such as anaerobes and Corynebacterium pyogenes were incriminated. The organisms mentioned are less susceptible to the bacteriostats at present in use. In the 1948 season more than one hundred and fifty outbreaks of lameness were reported. In the current season (1950) a number of outbreaks due to C. pyogenes have been reported and there were two cases suggestive of Erysipelothrix on clinical grounds, although the organism was not isolated. In both dipping-baths the concentration of the bacteriostat was below effective levels. Dairy Cattle Breeding Projects Artificial Insemination at Ruakura. —Winter Mating Group: This group was again used for training technicians. Four out of five candidates proved competent technically but one of these was temperamentally unsuitable. The experience gained over the past few years should prove valuable to any institution undertaking the training of technicians for commercial artificial insemination groups. Spring Mating : Artificial insemination moved a further step forward this season with the organization of the first two commercial groups by the Herd Recording Department; a Waikato group comprised 15 herds and 720 cows and a Taranaki group 15 herds and 600 cows. The cows were mainly grades, though a number of pedigrees were included. Charges were 15s. for grades and 30s. for pedigrees. Semen was provided by Ruakura without charge, the Dairy Board accepting responsibility for all other work. At Ruakura itself the normal experimental grade group was continued, while the pedigree group was also carried on.

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