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Histological examination of brain* sections showed changes similar to those described in infectious avian encephalomyelitis. Unfortunately no material was available for transmission tests, and although material was received later from the same farm, such transmissions were negative, as was also the histology, so it would appear that the suspect condition had cleared up in the interim. Infectious avian encephalomyelitis has never been diagnosed in New Zealand previously, but the above typical history and histological picture strongly suggest its existence, and a keen look-out will be kept in the next breeding-season. Dogs: Hepatitis Contagiosa Canis (Rubarth). —rSudden deaths in 3 dogs aged six weeks, eight weeks, and fifteen months were associated with lesions similar to those described for infectious hepatitis by Rubarth and other workers. These cases came from the Wairoa and Gisborne districts. The fiver-lesions were essentially areas of intralobular necrosis and haemorrhage and in the adjacent cells intranuclear inclusion bodies were seen. Cats : Lung-worm.—Mature nematode parasites were seen in the In rigs of a cat from the Wairoa district. The parasites were probably Aleurostrongylus spp., which require snails and slugs as intermediate hosts in their fife cycle. Research Work Sheep-breeding Projects Flushing Studies. —To obtain further data on the influence of live-weight changes in the breeding performance of ewes and, in particular, to study the effect of flushing on lambing percentage, a flock of 300 ewes, on 21st February, 1949, was split into two equal groups comparable in respect to five weight and degree of fatness. The group to be flushed was grazed thereafter for six weeks on an area of the best pasture available which had been specially spelled for the purpose. The control group was grazed on pastures designed to permit neither gain nor loss in body weight. Regular weekly check weights of all ewes were obtained to permit adequate control of the grazing management. At the end of six weeks both groups were run together again as a single flock. Yasectomized rams were run with both groups before and during the first week of the experimental period to obtain data on the time of onset of first heat periods. After this time fertile rams were introduced to both groups. All rams were raddled. The " flushed " group gained an average of 17*1 lb. per ewe over the six weeks. The control group gained only 5-2 lb. over the same time. Lambing performance of the two groups can be summarized as follows :

Lambing Performance

Of the 139 ewes conceiving in the control group, only 10*8 per cent, carried twins. The comparable figure for the flushed group was 30*1 per cent. From the work the following tentative conclusions have been reached : (1) Imposition of flushing treatment during the fortnight before the time when the number of ewes coming into oestrus for the first time reaches a maximum has a very slight effect, if any, upon the time of onset of the breeding-season.

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Group. Number Conceiving. Number Not Conceiving. Number of Lambs Carried. Number of Lambs Alive at One Month. Lambing Percentage.* Control Flushed 139 133 11 16 154 173 141 152 94-0 101-3 * Based 011 lambs alive at one month and ewes mated.