ANIMAL RESEARCH IN DOMINION

Waikato Times, Volume 127, Issue 21199, 23 August 1940, Page 12 (Supplement)

ANIMAL RESEARCH IN DOMINION

New Division’s First Report. Stock Diseases Fully Revieived. j ' A new division of the Department of Agriculture, the Animal Research Division, was formed on April 1, 1939. The first annual report of the new division by its actingdirector, Mr J. F. Filmer, is interesting reading because of its full review of all stock diseases recorded during the year. Facial Eczema.—The investigations have continued to be directed by the Facial Eczema Management Committee, and the Department owes its thanks to Dr. H. E. Annett and Messrs F. H. Anderson and Hayward, and also to Mr Bruce Levy, of the Department of Scientific and Industrial Research, for their services on this committee. The collaboration of officers of the Department of Scientific and Industrial Research has continued satisfactorily during the year. In the experiments at Ruakura and Karamu efforts were concentrated on an attempt to provide the chemists with pasture which was known to be toxic. In addition to the ewes and lambs which remained in the experimental paddocks throughout the season, test wethers were introduced each week and left for periods of a fortnight. Grass was collected daily, and some of this was fed to penned wethers again for fortnightly periods. It was hoped by this means to be able to determine whether or not the grass was toxic during any particular fortnightly period. However, though some liver derangement characteristic of facial eczema occurred in the experimental lambs, no symptoms were detected in any of the test wethers. This would indicate that, under the climatic conditions which obtained in the Waikato this year, the period of a fortnight was at no time long enough to induce the disease in wethers. The experiments are to be modified next season so as to use lambs as test animals, and they will be so arranged that data can be obtained concerning periods of varying lengths. One interesting observation was that for the second year no symptoms of facial eczema occurred in the paddock in which the pasture was kept green throughout by means of irrigation. No Further Outbreak The season throughout the majority of the North Island did not favour the appearance of facial eczema, but small outbreaks occurred on the East Coast, where the summer was much drier and hotter. Regular pasture inspection has been conducted on a number of farms by officers of the Fields Division and the Department of Scientific and Industrial Research, in addition to those of this Division. Officers of the Live-stock Division have assisted in collecting blood and urine samples and samples of organs for pathological examination where outbreaks have occurred. Comprehensive chemical surveys of pasture and soil analyses have been made, and though these have afforded little evidence concerning facial eczema they have provided a wealth of data which will be of great value in other respects.

Lambs livers have been sampled at weekly intervals at seven meat-works in the North Island and two in the South Island. In all 2588 specimens have been examined histologically. The great majority of these have been normal, but facial-eczema lesions appeared in some livers from the Kaiti Works during February and March. Organs and fluids from experimental and affected animals have been examined histologically and biochemically. Considerable attention has been given to the improvement of biochemical technique, and this has enabled photosensitising agents to be detected more readily, with the result that valuable data have been obtained. A study has been made of photosensitisation in experimental animals produced with known photosensitising agents and standard sources of light. A study has also been made of substances which cause the appearance of coproporphyrin in blood and urine, this being a symptom of facial eczema which has been detected during this year. Some experimental work has been done with substances capable of producing liver damage similar to that seen in facial eczema, special attention having been paid in this regard to analine. Photosensitisation This disease, which externally resembles facial eczema, but is distinguished from it by the absence of liver lesions, has been known in some strains of Southdowns for many years. It is considered probable that a predisposition to the disease is inherited. During the year biochemical studies have been made and a breeding experiment has been initiated to study the genetic aspect of the disease. Rape-scald.—Biochemical study of naturally incurring cases was undertaken but no results have so far been achieved. Photosensitising Plants.—A number of species of the genus Hypericum have been collected and feeding experiments are being initiated. One of these species has been blamed for the severe photosensitisation which sometimes occurs in the Marlborough district. Sheep Mortality, Canterbury.—Following the field survey by veterinarians and agriculturists, it was considered that further progress necessitated intensive investigations on an experimental farm with a bad history. Such a farm has been leased in the Kirwee district as from January 1, 1940, and experiments have been initiated to study all phases of sheep mortality which occurs in the Canterbury district, especially in wet seasons. Special attention is being paid to the effect of parasite control and various methods of sheep management and feeding. The role played by parasites must be closely studied, and, regular chemical analyses of pasture and supplementary feeds are being made. The Canterbury Agricultural College is actively collaborating in this work and is especially interesting itself in the digestibility of pasture and supplementary crops grown in Canterbury. Incidence of Mastitis Experiments have been inaugurated to test the effect of milking-machine adjutsments on the incidence of mastitis in an experimental herd. Research is being undertaken in connection with the evolution of a standard milking-machine, with particular attention to the mechanical simplicity and durability, milk hygiene, and the effect produced on the udder. Observations have been made on the effect of milking-machines on the production of mastitis in a number of dairy herds. Consideration is being given to the possibility of testing the performance of milking-machine accessories. A committee has been set up to co-ordinate the work in connection with milking-machines, and the gratitude of the Department is due to the representatives of the Dairy Board and the Taranaki Federation of Dairies, as well as to the Director of the Dairy Research Institute, who have served on this committee. Regular observations have been made on the occurrence of mastitis in two experimental herds. General field observations have been made on the occurrence of the disease in the Waikato. The mastitis-control scheme which has been operating in that district during the past eight years has been

critically reviewed during this year and it is considered that this scheme will need considerable revision before it can be applied generally. It is hoped to start work in an experimental herd next year with a view to exploring the possibility of devising a more efficient control scheme. A special bacteriological study has been continued with a view to determining the types of organisms responsible for mastitis in New Zealand. Preliminary work has been done to establish a technique for studying the effect of non-stripping. Grass Staggers A study has been made of the seasonal variations of magnesium in the blood of cows at Ruakura, Massey Agricultural College, and Wallaceville. The effect of various pasture species and of pasture management and of the administration of magnesium compounds on the blood magnesium status has also been studied. Haematological examination of field cases have been made, and these have indicated that the disease is distinct from one which it resembles clinically in Australia. “Rye-grass Staggers” in Sheep and Cattle. —Some biochemical studies have been made and feeding experiments have been conducted with pasture collected from affected paddocks. Sterility. —The investigations connected with the diagnosis of bull sterility by semen examinations have been continued. The Technical Officer of the Dairy Board has collaborated in making a critical examination of the results of this year’s work. Should the result of this indicate that the method is of sufficient value, a service to dairy-farmers will be initiated whereby it may be made available generally. The experiments designed to study the effect of high protein rations on bull sterility have been continued. There is so far no indication that any dairy pastures usually grazed by bulls in New Zealand are sufficiently high in proteins to cause sterility. The experiments to investigate the effect of protein on sterility in male rats have been continued and some interesting results are being obtained. With a view to determining the effect of nutrition on dairy-cow sterility, regular pasture observations have been made on a number of dairy-farms throughout the year. During the next season the herd-testing branch of the Dairy Board will collaborate in this work. Artificial Insemination. —A second year’s work has been done on eleven dairy farms; the results indicate that before artificial insemination could be widely used in New Zealand further information is required concerning technique. It is intended to use artificial insemination entirely on one experimental herd next season, and it is hoped by this means that valuable data will be obtained. Contagious Abortion. —The first calves were inoculated this year in an experiment designed to test the value of calf vaccination in preventing this disease. The project is a longterm one and the work will be continued over several years. Pig Nutrition Experiments have demonstrated the beneficial effect of feeding sows for six weeks after weaning on the number of the next litter and the beneficial effect of feeding for six weeks before farrowing on the size of individuals in the litter. The effect of restricted feeding in reducing the thickness of back fat in baconers has been demonstrated, and co-opera-tive experiments on a number of farms have confirmed these results. Experiments have shown that, at the present prices, root crops fed during the winter to store pigs return a profit representing from £4O to £l4O per acre of root crops. Dairy Cow Nutrition. —Experiments have been commenced to determine the best methods of managing and supplementing pastures for dairy cows. The initial results indicate that proper pasture management can materially ameliorate the shortage of feed in winter. Chilled Beef Production. —Encouraging results have been obtained in experiments designed to determine if chilled beef can be profitably produced on Waikato sheep farms.

Curd Feeding to Poultry.—Experiments indicate tKat tke feeding of curd from skimmed milk to poultry is at least as profitable as feeding skimmed milk to pigs. Pasture Research. —A number of projects have been conducted in collaboration with the Fields Division, and some of these will doubtless be reported more fully by the Director of that Division. Feed Flavour.—Experiments have indicated that feed flavour caused by clovery pastures in spring can be controlled by pasture management and special grazing practices. Rate of Growth of Pasture.— —This has been measured at Ruakura and Karamu throughout the year, and it has been found that half the total production takes place from October to December, while rather less than one-tenth of the total production takes place from April to June. This emphasises the very real necessity for special management and supplementing of pastures to increase winter feed. Ragwort. —Experiments have been continued to determine the best time of the year at which to apply sodium chlorate. Cobalt Deficiency Experiments at Mamakji have indicated that bush sickness can be completely controlled by annual topdressing with small amnouts of cobalt. It is hoped to produce this year the third generation of sheep on cobalt-deficient paddocks which have been treated in this way. Attention is drawn to a statement in the report of the Superintendent, Ruakura Animal Research Station, that the Mamaku Plateau offers definite possibilities for sheep-farming, if the clearing, stumping, ploughing, and resowing of grass of the abandoned farms were undertaken. The duration of the effect of larger dressings of cobalt is being studied, and the results indicate the possibility of these larger dressings being used successfully at longer intervals on hill pastures. Tests have been made to discover the effect of administering large doses of cobalt at monthly intervals, as successful results have been reported by one farmer using this practise. The results indicate that, while sheep may be kept alive in this way and cases of bush sickness may be cured, optimum growth cannot be induced. Chemical work has indicated the value of the cobalt status of the liver for diagnosing bush sickness. The fundamental action of cobalt is being studied by the feednig of liver fractions. The cobalt survey of pastures, soils, and limestones has been continued. Experiments have been conducted in collaboration with an officer of the Department of Scientific and Industrial Research with radioactive cobalt to study the distribution of cobalt within the body. In collaboration with the Cawthron Institute a further study has been made of the technique of cobalt estimation in pasture, soil, and animal products. During the year a pamphlet giving up-to-date information concerning the diagnosis, treatment, and prevention of bush sickness was issued under the joint auspices of the Department of Agriculture and the Cawthron Institute. Bone Pathology Bone abnormalities have been reported in cattle, sheep, pigs, and poultry, and a special study of bone pathology has been commenced to assist in determining the causes of this disease. Pulpy Kidney.—Experiments have been conducted with a view to producing a more effective vaccine. Blackleg in Sheep. This disease, which is generally confined to cattle, was diagnosed in sheep in the Wanganui district and it has been controlled by the use of a vaccine. Poisonous Plants.—Feeding experiments have been conducted to study the effect of several plants suspected of causing stock mortality. Chemistry of Fats.—lnvestigations have been continued into the occurence of vitamins in iv/ew Zealand butters, fish oils, and pastures. Some w r ork has also been done on the quality of bacon fat produced with some of the more common New Zealand rations.