Transactions of RHASS Volume 1940 - Page 066
Image details
| Year | 1940 |
|---|---|
| Transcription |
|
| OCR Text |
120 AGRICULTURAL RESEARCH IN SCOTLAND IN 1939. gation of the development of the disease in its e remains undetermined. Contagious Bovine Abortion.—Fundamental studies TIIE ROWETT RESEARCH INSTITUTE. BUCKSBURN, ABERDEEN. Dried Grass—In experiments with poultry, dried proved satisfactory when used to the extent ‘of 20 per cent of the total ration. Hatchability, growth, and egg production were good. As the dried grass used had a fairly high fibre content (20 per cent), a large part of the remainder of the 'ation was composed of concentrated foods, such as maize. Another experiment showed that the allowance of con- centrates to birds on winter pasture could not be appreciably reduced and maximum production maintained. .It has beeii concluded in the meantime, therefore, that grass as a means of reducing the consumption by poultry of cereal concentrates can best be used by cutting and drying and then incorporating it in the ration. grass .Grass Silage—Silage has been successfully made in shallow pits from young short grass without molasses. Adequate and even consolidation is the essential factor. Cows have eaten up r V . . . . . to.1.)0 lb. per day 0tps11age made in this way, and have main- tained an average yield of 5 gallons per day over a period of two months on nothing but silage. No taint has been observed in the milk, but the colour was visibly richer. Restricted Feeding of Pigs—A saving of approximately 1 cwt. of concentrates was obtained on a group of pigs fed on a restricted scale. They took fourteen days longer to e‘et to bacon weight (224 lb.) than a group fed ad lib. The average number of pounds of food per pound live-weight increase in the restricted group was 3-24 lb. Pasture for Fattening Pigs—A saving of 35 lb. 103 days was obtained by folding summer pasture. of food in groups of pigs over good subject of systematic biochemical study, and further investj. ' arly phases has been carried out. \Vhile much information of a negatiVe character has been obtained the nature of the diseaSe still . i of Biueclla abortus as it affects laboratory animals are being continued, and the Association is working on this probleni in close collaboration with the Agricultural Research Council. Annicm/rianL r. uSEARCH IN SCOTLAND IN 1939. 121 I nermscd use of Straw for Feeding—Preliminary work has shown that the feeding value of straw can be increased con- siderably by treatment with caustic soda prior to feeding. Feeding trials with cattle and sheep are under way. Fowl Paralysis—Results of experiments extending over several years are as follow s :— The disease is of an infectious nature and the agent responsible is transmitted via the egg. Effective control in several outbreaks can be obtained (a) by removing the chicks at day—old to clean pasture and premises well away from the affected area, or (b) by confining the. whole stock indoors for at least one generation and replacing the floor litter at weekly intervals. THE SCOTTISH PLANT BREEDING STATION. CRAIGS HOUSE, CORSTORPHINE, EDINBURGH. At the Station plant breeding experiments are in progress with all the crop plants of major importance in Scottish agriculture. Each year it is customary to review in ‘The Transactions’ one section of the work, and on this occasion the subject-matter will be confined to virus diseases of potatoes. Every potato grower is familiar with the leaf roll and mosaic diseases of the potato. These diseases are caused by the infection of plants with one or more of the agents known as viruses. Leaf roll is the visible sign of infection with a single virus, usually referred to as the leaf roll virus. Mosaic diseases, however, are varied in their type and severity, and it is now known that several viruses either singly or in com- bination may cause them. These viruses are distinguished for reference by letters of the alphabet. Thus in this review the letters A, B, C, X, and Y all refer to viruses which in certain circumstances are capable of producing mosaic diseases upon potato plants. The virus diseases problem presents two widely different aspects to the potato breeder. Firstly, these diseases have immediate effects on the plants used as parents in breeding and on the offspring of these parents. Secondly, there are the possibilities of breeding potato varieties which are immune from or resistant to the diseases caused by potato viruses. An extended examination of diseased plants and of several thousand seedlings derived from them has shown that, although fl0Wering is reduced considerably and breeding impeded by the presence of virus diseases, the viruses causing the diseases are not transmitted from parent to offspring through the seed VOL. Lu, 1 a”)... ovum swu i Wit-'me awn-1x?» mi an. “"KMa—drmh loa “an. a“ '1‘." “Pa—an: M» gun - wi‘: v.4 em ' _ W_um~¢ 3;» ~. 5‘ 3 '5». ‘- |
| Title | Transactions of RHASS Volume 1940 - Page 066 |
