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It is believed that the technique was not - responsible for the poor results gained. With regard to " Ngahiwi," interesting facts were observed: — ■....-.• (1) Semen in bulls where sperm morphology is not found to be good on microscopical examination, fluctuates in quantity ejaculated at each service. (2) Motility and density of sperm of each service differs. Occasionally no semen is delivered. In one trial of four services the first two gave no semen, the third plenty of optimum density and motility and the fourth a poor supply of thin semen. The third service, however, was non-motile by mid-day. It is this fluctuation in bulls with abnormally developed spermatozoa that, combined with the frequent short-lived motility and poor density, makes service with such bulls very uncertain and leads to considerable return of cows. Whether infection is to be found in such types of seminal fluid is still unknown, opportunities for working on this point not having presented themselves. Certainly no outbreaks of sterility resulted from the artificial insemination trials. It is believed that there is little fluctuation of semen in completely normal bulls, and this forms part of the new year programme. Attempts to obtain seminal fluid by other means than cow service have completely failed. The result of male sterility work in rats is contained in Dr. Cunningham's report:— "It was reported previously that two types of sterility could now be produced in rats :-— " (a) That due to excess dietary protein, and " (b) That due to dietary protein of poor biological value. " Work on the second type of sterility has yielded hopeful results concerning the nutrition requirements of the testis. It has indicated that certain of the amino-acids are essential to the production of normal and healthy spermatozoa. " The work has opened up an entirely new field of investigation and progress is necessarily slow. Lack of funds for the purchase of amino-acids, moreover, greatly handicaps the progress. "An experiment with pigs using a diet with biologically poor protein has given results, so far, which suggest that in this species as well as in rats, the nature of the protein may have an important bearing on the reproductive capacity." Sterility in Sheep. Artificial insemination in sheep during the early part of the year demonstrated that coincident with the very great flush of pasture in the autumn, many rams were not fertilizing ewes as they should. At Wallaceville the rams, Southdown and Romney, after a short season of service became sterile, no semen being formed, and they remained in this condition for several weeks, thus tending to produce two crops of lambs. The reason for such abnormality, although apparently originating in diet, cannot yet be suggested. Paspaltjm Staggers. Investigation into paspalum staggers which was seen for the first time in New Zealand last April, has shown definitely that the ergotized seed head is toxic and sets up the trouble when fed to cattle. Preliminary experiments on guinea-pigs and rats with small quantities of ergot gave no harmful results. A collection of plant heads was, however, made in February and March, and a feeding experiment on two heifers arranged. Each received 2| lb. daily of seed head containing at least 20 per cent, ergotized seed. Typical symptoms of staggering were observed in eight days. The heifers, when turned out, took about six days to return to normal. Further trials with ergotized seed alone got by screening, have so far given only nervous muscular twitchings and have not resulted in the inability to use the limbs and consequent staggering and falling when excited. ... . ... Grass Staggers, .......... .... ■ - ■ Grass-staggers work is to be seen in Dr. Cunningham's report (attached). ,-.'■■ ■,■■■ SHEEP DISEASES. : -. Photosensitivity. , ■■■•• • •>,"■• Hereditary Sensitivity. —A breeding experiment was attempted with Southdowns, using a ram which was sensitive to light and had to be kept in a, darkened shed during the day. He was bred to eight Southdown ewes, two from an affected flock and six from,a Government flock. No lambs were affected at birth, but one ram lamb from a ewe known to have produced affected lambs previously,, become photosensitive at four" weeks old when he commenced eating green pasture.. . Placed on. hay for a fortnight and then kept in the sun,, this lamb was found to be quite insensitive, but when. fed green maize or other green forms of food, he quickly became sensitive and sought shade. Post mortem has yielded no apparent anatomical defect to account for this. Facial eczema. — Photosensitivity with oedema and scab formation of the exposed parts of the skin, was noticeable to some extent again both in the North and South Islands. An examination of. the South Island pastures has shown the presence of species of native hypericum, and it is considered this might be causative in the southern areas. A feeding experiment in Merinos on 500 acres of lagoon land has been arranged. The photosensitivity of Romneys of the Gisborne district has again been investigated, but beyond finding the phylloerythrin in bile samples no great advance has been made. The condition occurs apparently where there is a combination of high temperature, plentiful rainfall, and intermittent dull and bright days, so that chlorophyll content of pasture is abnormally high and growth of pasture very fast. The factor causing liver damage one believes occurs in such pasture. In letters received from Dr. Steyn of the Onderstepoort Laboratory, South Africa, it has been stated that a similar condition has been known in similar circumstances, and need not necessarily occur on the plants usually blamed in South Africa. .. .: Feeding green leaves of H. perforatum in quantity to sheep has not resulted in photosensitivity, nor has any result been obtained in feeding of native H. japonicum- to Merino lambs. Mycotic .Dermatitis. Mycotic dermatitis has been recognized over a wide area, but only occurs in small numbers of sheep, particularly in Merinos. The use of rabbits for diagnosis of the condition is proving useful. Scarification and rubbing in of scab from an affected sheep produces a very definite dry, raised scab on rabbits' skins in six days. Haemolysis on blood plates also affords a useful means of isolating the organism.

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