109 REDUCING LOSSES AND DISEASE LEVELS IN SHEEP by Richard Bristol1 Veterinary Medicine and Sheep There is a rather fanciful and popular rumor that has made the rounds for centuries that we should attempt to dispel; the saying 11 I a sick sheep is a dead sheep 11 1 is probably one of the greater falsehoods of the century. Sheep can and do survive surgical procedures that might cause other species to succumb. Sheep can and do recover from pneumonia I parasitium and other organic diseases if a proper diagnosis is made and proper treatment instituted. Nursed I treated and cared for with any reasonable degree of intelligence sheep will respond just as satisfactorily to sulfonamides I antibiotics I vaccines I pharamaceuticals and surgical procedures as any other species of animal. For too long we have considered the treatment of the individual sheep as an uneconomical practice. May I submit to you that the basis for diagnosis of flock conditions remains the physical inspection I examination 1 isolation of the causative agent and treatment of the individual animal. Further 1 an adequate dose of the most commonly used antibiotic in veterinary medicine does not exceed 1 1/2 cents a day for a lamb or 5 cents a day for a 100-pound adult. An adequate dose schedule of the more expensive broad spectrum antibiotics would not exceed 18 to 25 cents for each day of therapy. It is possible I using these figures as a basis I to treat a sheep for a known responsive condition for from 15 cents to $2.50 for a 10-day period. This is not uneconomical in view of the lamb or adult animal's actual value. The sheep I as a research animal 1 has proved itself as an excellent tool to exemplify the characteristics and responses of other ruminants. To this end it has been used extensively in veterinary medical research. This may be to a disadvantage I however I for I although research on sheep or research using sheep as a medium is conducted continually, research to find the answers to the problems of the producer has been limited in many states. Industry Disease Losses The actual loss levels of the sheep industry at the ewe I lamb and the feeder level have varied considerably from year to year. As our ability to separate and differentiate one disease from another increases 1 new categories University. 1 Assistant professor of veterinary medicine and surgery 1 Iowa State
110 of disease loss are opened. An increase in the efficiency of our disease reportin9 system has helped immeasurably in our efforts to categorize sheep disease losses. These losses fall into two completely different and distinct groups: (1) those losses that affect the ewe, lamb and wool producer and (2) those that affect feeder lambs for the meat consumer market. In the first group we are concerned with the diseases causing an interference in conception, abortion, respiratory infections of the young, contagious ovine ecthyma, blue tongue, naval ill, scrapie, scabies, screw worms, parasitisms, nutritional disease, pregnancy disease and other conditions that primarily affect mating, conceiving and raising sheep to a profitable economic unit. In the second group we are concerned with diseases that affect the lamb from the time it leaves the flock until it reaches the consumer in the form of animal protein. The diseases that concern the market lamb primarily are enterotoxemia, tetanus, abscesses in various parts of the body, parasites, nutritional disease and urolithiasis, in addition to many others. The resources that are available to effectively combat all of the before mentioned conditions are numerous and varied: Efficient and effective antibiotics, sulfonamides and other chemotherapeutic agents for diseases which are bacterial in origin, such as the pneumonias and abscesses. Vaccines for blue tongue, contagious cethyma, tetanus, enterotoxemia and, more recently, vibrionic abortion. Parasiticides such as phenothiazine, organic phosphates and thiabendazole that are effective yet relatively non-toxic to the animal. Our knowledge about the basic nutritional necessities for sustaining life, reproduction and maximum gain is increasing each year. Research reports and reports of the results of inspections made at public stockyards by the Animal Disease Eradication Division, Agricultural Research Service, show the following: In a study made over a three-year period by the University of Montana Agricultural Experiment Station involving two flocks of sheep and 7,191 births, it was found that 23 1/2 percent of the lambs died between birth and weaning. Autopsies were conducted on 62 percent of the lambs. Pneumonia, starvation and dysentery accounted for almost 42 percent of the deaths! Further, 56 percent of those dying did so within the first three days of life; 73 percent died within the first five days.
111 In a study of pre-weaning death losses in lambs at the Illinois Agricultural Experiment Station over a 3 7 -year period, it was found that 18. 8 percent of the lambs failed to survive 120 days of life! Reports of the Animal Disease Eradication Service indicate that of 13,000,000 sheep inspected in 1963 at public stockyards, more than 36,000 were showing signs of clinical pneumonia, more than 38,000 clinical evidence of arthritis and 300 showing signs of dysentery. Similar figures are reported for 1962, and the figures for 1964 show a definite increase. You will note that pneumonia, arthritis and dysentery account for many of the disease conditions in market sheep as well as in the newborn lamb. The most critical part of the sheep's life is at birth. It has been known for centuries that strict attention must be paid to the ewe and lamb at this time. This point has been emphasized by veterinarians, sheep extension specialists and textbooks for many years. Yet, our greatest losses still occur during this critical period. All of the antibiotics, sulfonamides 1 vaccines and chemotherapeutic agents cannot compensate for a lack of adequate care during the lambing season. The basic procedures to prevent just such losses at lambing time were laid down by Columella in AD 65! Alexander in Australia has shown that with warmth, care and attention these losses can be prevented! Further, losses can be prevented by proper management procedures and prompt recognition of the disease process I coupled with competent professional help. The antibiotics I sulfonamides and vaccines cannot help a moribund animal, but are efficient, proven and dependable when applied early in the disease process. Resources Available In addition to the use of vaccines in the prevention of disease and the use of antibiotics and other therapeutic agents to combat disease, there are other resources available to assist the producer in combatting disease losses. Primarily these resources are: The practicing veterinarian in the diagnosis I of disease. treatment and prevention The various state, federal and commercial laboratories and diagnostic centers available for consultation in sheep disease problems. The use of agricultural extension specialists on the county, state and university level to assist in solving management problems that contribute to disease losses. It is not enough to know that these people exist; they must be used by the producer to the fullest extent if disease loss levels are to be reduced.
112 Basic Stumbling Blocks First and foremost, the producer must learn to use and apply all of our present fund of knowledge to reduce disease loss levels. Until this is done, discussions of the problems involved are merely academic. Further 1 we need to return a certain amount of the income from the sheep industry to research projects that will directly benefit the producer. Pneumonia, arthritis 1 epidymitis I mastitis 1 urolithiasis and many other diseases need intensive and thorough investigation. Funds are needed to do this! The Fact Book of Agriculture points out that industry returns about 3 percent of its gross prqduct for research purposes, whereas only 1 percent of the gross product of agriculture is returned for research purposes. This book further points out that for every $1 spent for research, $25 is returned! The Future With the advent of supersonic transportation the world has drawn closer together. This applies to disease as well as merchandising. We need to be constantly alert to the introduction of sheep diseases foreign to this country. This can be accomplished if we learn to use those who are best qualified to recognize disease conditions that deviate from known disease problems. With increased emphasis upon disease research and the subsequent greater knowledge available to combat disease 1 we can anticipate that we will have the ability to control disease losses to a greater extent than we now have. The producer must learn 1 however 1 to apply known sound management practices and preventive medicine procedures on a practical basis if he is to realize a greater potential from his lambing flock or his feeder operation.
113 REFERENCES Alexander, G., J. E. Petersen and R. H. Watson, "Neonatal Mortality in Lambs," Australian Veterinary Journal 35:433-441, 1959. Alexander, G. and J. E. Petersen, "Neonatal Mortality in Lambs," Australian Veterinary Journal 37(10) :371-381, 1961. Hickey, F., "Death and Reproductive Rates of Sheep," New Zealand Journal of Agricultural Research 3 (2) :332-344, 1960. Hoversland, A. S., J. Stafford and J. L. VanHorn I "Lamb and Ewe Characteristics Associated with Lamb Mortality," Journal of Animal Science 2 2 (3) :856 1 1963. Abstract. Logace, Andre, W. D. Pounden, D. S. Bell and K. D. Weide, "Factors Influencing the Incidence of Chronic Pneumonia in Lambs," American Journal of Veterinary Research 22(91) :1015-1019, 1961. Safford, J. W. and A. S. Hoversland, "A Study of Lamb Mortality on the Western Range," Journal of Animal Science 19:165-173, 1960. United States Department of Agriculture. ARS, ADE, Consolidated Reports: Animal Diseases at Public Stockyards and Establishments. October 12, 1964. United States Department of Agriculture. ARS, ADE, Consolidated Reports: Animal Diseases at Public Stockyards and Establishments. Fiscal year, 1963. United States Department of Agriculture. ARS, ADE, Consolidated Reports: Animal Diseases at Public Stockyards and Establishments. Calendar year, 1962. United States Department of Agriculture. Fact Book of U.S. Agriculture. Revised March, 1963. Vetter, R. L., H. W. Norton and U. S. Garrigus, "A Study of Pre-weaning Death Losses in Lambs," Journal of Animal Science.