Swine Erysipelas (Diamond Skin Disease) 373 infected. Shipment of such hogs should Step is to give all of them the facts be restricted as long as the disease about the disease and the need to con- exists in this country. The marketing trol it. Problems should be discussed of swine fed raw garbage should not be with representatives of the industry as permitted at any time, unless the pork the program progresses. They should from them is specially heat treated. be kept informed of gains made and Any vehicles used to haul swine that setbacks encountered. are fed raw garbage should be cleaned and disinfected after they are used. F. J. MuLHERN became head of the Ve- Swine fed cooked garbage could be sicular Exanthema Eradication Section of sent to market if inspected by a State the Agricultural Research Service in ig§2. or Federal inspector and if all swine on Previously he was employed in the foot-and- the premises are free of the disease. mouth disease eradication program in Mex- The swine that move should be accom- ico and was the Department's representative panied by a certificate issued by a during an outbreak of foot-and-mouth dis- Federal or State inspector. ease in Canada. He holds the degree of All vehicles, facilities, feed, watering doctor of veterinary medicine from Alabama and rest stations, and loading and un- Polytechnic Institute. Rejoined the Depart- loading points used for swine within ment of Agriculture in 1945. or from the State or States involved in W. C. PATTERSON is a veterinarian an outbreak should be cleaned and in the Animal Disease and Parasite Re- disinfected each time they are used. search Branch of the Agricultural Research The informational phase of an eradi- Service. He is a graduate of Pennsylvania cation program is important. The co- State University and has the degree of veter- operation of all parts of the livestock inary medicine from the University of Penn- industry is necessary to control and sylvania. Dr. Patterson joined the Depart- eradicate the disease. Therefore, a first ment of Agriculture in ig^i.

Swine Erysipelas {Diamond Skin Disease)

RICHARD D. SHUMAN AND O. L. OSTEEN

SWINE erysipelas is present in the disease was present in this country United States wherever hogs are before 1900. G. T, Creech, also of the raised. It is worst in regions, like the Bureau of Animal Industry, in 1921 Midwest, where the hog population is demonstrated the relationship of dia- dense. It is serious in Europe, parts of mond skin disease (a clinical form of Asia, and North America. swine erysipelas) and the causative R. Koch, F. A. J. Lofíler, L. Pasteur, agent of erysipelas. The disease caused and M. L. Thuillier—all of whom are little trouble until the 1930's, when famous in scientific history—are asso- A. A. Fosterman, a veterinarian in ciated with the discovery of the causa- South Dakota, directed attention to tive organism of erysipelas in the its acute aspect. Swine erysipelas has i88o's. Previously swine erysipelas was since become one of the most serious confused with anthrax. The work of hazards of the swine industry. Theobold Smith, in the former Bureau The causative agent is a bacte- of Animal Industry, showed that the rium, Erysipelothrix rhusiopathiae. It is a 374 Yearbook of Agriculture 1956 hardy organism and can live in dead the soil in the hog lots with their animal tissue and decaying matter. droppings. It can resist the effects of pickling, Animals become infected through smoking, freezing, and drying of contact with the soil that contains the meats for long periods. It is rather organism—by ingestion of contami- sensitive to heat, however, and is killed nated feed and water and by infection at temperatures necessary to cook the of wounds. Fighting may lead to chop or roast well. wounds of the lips, face, and shoulders. The organism is considered to live Sharp rocks, glass, and other objects in the soil as a saprophyte and can cause wounds in and around the claws multiply under favorable conditions or lips while rooting. Protruding nails of moisture and in soil rich in humus. or broken boards and pieces of wire Disinfectants commonly available fence also can cause tears and breaks of and used according to directions will the skin. destroy it. One sick hog can cause an outbreak The organisms have been found in of the disease through its elimination all parts of the world—and in a wide of the organism in its dung and urine. variety of animals, birds, fish, and Because the organism can be found insects. Of major economic importance also in the circulating blood of an in- is the effect of the disease in swine, fected animal, there is a possibility that turkeys, and sheep. bloodsucking insects may transmit the Infection of people is not uncommon disease to other hogs. G. Wellmann of (erysipeloid). It is an occupational Germany has shown this to be possible hazard of veterinarians, persons who by experimentally transmitting the handle fresh meat and meat products, disease with biting flies. and commercial handlers of marine fish. Home butchering and processing SWINE ERYSIPELAS has a peculiar be- of pork also has been the source of havior: Why did the disease apparently infection of people. lie dormant for many years and then Probably the chief source- of swine become a menace in the early 1930's? erysipelas infection is the organism Why does it show itself on a farm for present in the soil. A saprophyte, the several seasons and then seemingly dis- organism can live on dead and de- appear? Why do some areas remain caying organic material—it does not known as erysipelas areas? Some out- require a living animal to maintain breaks years ago could have been con- itself. Perhaps it has always been fused with hog cholera (they can occur present as a soil organism. at the same time), but the real reason Another source is the animal carrier. is not known. The organism can exist in the tonsils The other peculiarities can be ex- and the lymphoid tissue of the intesti- plained on the basis of what is known nal tract of apparently normal swine. to be possible. We have known for a Hogs that become affected with long time that the causative agent can swine erysipelas may or may not be one of relatively low virulence or show actual clinical symptoms of the one of great virulency: Because it is disease, but in each instance it is not always the same, its ability to pro- possible for the organism to be elimi- duce disease can vary a lot. It is pos- nated from the animal's body through sible that we may even be dealing with the feces and urine. Hogs that die different strains or variants of the same from the disease and remain un- organism. At any rate, since the infec- detected in the field can contaminate tiveness of an organism can be increased the soil and can be the source of an or lowered by artificial means in the outbreak when eaten by other hogs. laboratory, it is very likely that such Very likely birds and other wildlife external factors as climate and soil con- that carry the organism contaminate ditions also can alter its disease-pro- Swine Erysipelas (Diamond Skin Disease) 375 ducing ability. This could then be skin disease, or the urticarial form of demonstrated on the farm by either a swine erysipelas. This phase is marked high incidence of disease, with many by light-pink to dark-purple areas on dead animals, or a low incidence, with the skin that usually become raised just a few sick ones in the herd. and firm to the touch and in most Swine erysipelas also can be present instances have clearly defined boiders. in a herd in such a mild form that it re- The shape is quite characteristic when mains unnoticed. Many animals there- seen or felt, because the outline of the fore become immune through natural skin lesion assumes a square, a rec- infection. On a farm wehere this condi- tangular, or a rhomboidal geometric tion occurs, one could easily conclude pattern. The lesions might join and that erysipelas died out or disappeared, cover quite a large area of the skin. although actually it was still there. All Although the lesions are best seen on that would be needed to change this a light-skinned animal, they can be situation into an outbreak would be an felt (but are easily overlooked in increased virulency of the organism either case, particularly if they are not and the presence of susceptible hogs. too numerous) on animals with darker skins. The number of "diamond skin" THE CLINICAL SYMPTOMS of swine ery- lesions can vary from one to so many sipelas are classed as acute, subacute, that it would be hard to count them. and chronic. The skin lesions may disappear in Acute swine erysipelas is character- several days, or they may become ized by its sudden onset. Many animals areas of dry, firm, darkened, scabby, in the herd may be affected at once. dead skin and under tissue. These Only a few may be visibly sick, but a areas of dead skin will eventually fall number of others may run tempera- off, leaving an ugly scarred area. It is tures of over 104°. Sick pigs tend to here that one will also see loss of tips stay where they are bedded, yet at the of the ears and tail. Secondary infec- same time their eyes give an impres- tion usually takes place during this sion of alertness. If stirred up and stage and prolongs the healing process. forced to move, they will protest with Although the mortality rate of hogs squeals as though it were painful to put showing diamond skin disease may weight on their feet. Sometimes the not be particularly high, animals that animals may show a peculiar stilty and have it will probably be afifected with stiff gait, or they may stand with their arthritis and the owner will be left feet under them, and head hanging with a number of pigs, which are un- down, so that the back line has an profitable to feed out. arched appearance. The attitude be- It is easier to think of the subacute comes one of dejection or depression. form as being less severe than the Left alone, they quickly make them- acute form. The animals seem to be selves as comfortable as possible in the less sick. The temperature may not be bedding again. Most animals show lit- so high. The hogs may show more tle desire for food or go off feed alto- interest in food. A few diamond-skin gether. A not uncommon symptom is lesions may appear. The animals do nausea and vomiting. Some animals not stay sick for so long a time. breathe with difficulty and have a Many hogs that live through the husky cough. If there is any change in acute and subacute forms do not the feces, it is more likely to be dry and always recover completely, because reduced in quantity. Several of the an infection of the joints commonly pigs may die suddenly; others will be occurs during the attack and can obviously sick, as we described, and a progress to a chronic or arthritic few may die in 7 or 10 days. form. Infection of the joints also can During the acute phase, many hogs occur without the animal's being may develop what is called diamond noticeably sick. Infection of the knee, 376 Yearbook of Agriculture 1956 hock, and the toes is most frequent. be docked at the packinghouse. Many Besides the noticeable lameness, shift- thousands of dollars are lost annually ing of weight, and other signs of pain in this manner, as diseased tissue re- in the legs, there is a gradual enlarge- quires trimming out as well as the ment of the affected joint, which will removal of visibly affected joints. also feel hot to the touch. Sometimes the symptoms disappear altogether, but THE DIAGNOSIS of swine erysipelas at may show up again. Many, however, times can be quite diflicult, and it is get progressively worse, and the arthri- well to remember that diseases—hog tis leads to bony enlargements and cholera and salmonellosis, for example thickening of the soft parts, resulting in —other than erysipelas can be present permanent deformity of the affected in herds at the same time. joint. This condition in hogs is similar Whenever an owner experiences sud- to rheumatoid arthritis in man. In- den deaths in hogs for no apparent volvement of the heart is not uncom- reason, he should consult his veteri- mon. It is referred to as endocarditis narian immediately. and brings about a cauliflower-like Diagnostic serological tests have been growth at the site of the inflammation. developed, but there are still definite Injuries and the absence of a proper limitations on their general use. Serv- nutritional balance or adequate as- ice laboratories are invaluable in as- similation of the mineral elements can sisting the veterinarian in his diagnosis. cause lameness. Thus it might be Early diagnosis and treatment can confused with swine erysipelas. Other put hogs on the road to recovery sooner recognized causes of arthritis include and with less overall damage to the infection with streptococcus, staphy- herd. Antibiotics alone and antibiotics lococcus, brucella, and salmonella or- with a specific immune serum are ganisms. S. H. McNutt, T. S. Leith, useful in treating swine erysipelas. and C. K. Underbjerg, as well as W. P. Biologies are available to the veteri- Switzer, isolated a filterable agent that narian. Hyperimmune scrum was the may be of significance in this regard. only tool available before 1938, and it Despite all these possibilities, we know was not always adequate. Vaccination, of no survey into the causes of arthritis for which a living virulent culture of in swine that would alter the picture the causative organism of swdne ery- presented by G. G. Grey, O. L. sipelas was used along with hyper- Osteen, and H. W. Schoening in 1941. immune serum, had been practiced in They examined 472 joints of hogs that Europe for many years. came from gr counties in 14 States; The Department of Agriculture, in they found the swine erysipelas organ- cooperation with the Nebraska Bureau ism in 375, or 76.5 percent, of the joints. of Animal Industry and the University of Nebraska, set up a program for DEATH LOSSES can run from none to introducing that method of control on 75 percent, but swine erysipelas is more an experimental basis. In the begin- noted for its crippling effect than for ning only a few States were permitted the deaths it causes. The hogs cannot to use live-culture vaccine, but as the get around so well; for a while they results from the field were quite en- show little interest in food, and there- couraging, the program was extended fore they become unthrifty. This sys- under the terms of a cooperative agree- temic effect of the disease—plus the ment. Up to 1956, 26 States were permanent damage to the joints and permitted to use the vaccine. The even the heart—leaves an animal in number of pigs vaccinated has in- such a condition that it never does very creased; in 1954 they numbered more well. It remains rough, undersized, or than 5 million head. An average of backward in growth. more than 2 million swine has been Those that do reach the market may vaccinated annually since 1943. Diseases of Baby Pigs 377 Other methods of vaccination have animals are bought; isolate newly pur- used the principle of a living but mild chased animals for at least 30 days vaccine, or what has been called an before introducing them into the herd; "avirulent" vaccine. This type of vac- keep pens and pastures clean and sani- cine does not require the use of the tary; use disinfectants often and ac- protective serum. cording to directions; and feed a bal- There also have been introduced anced ration. bacterins that do not contain living organisms. One is called the adsórbate RICHARD D. SHUMAN is a veterinarian and the other is the lyso bacterin. The in the Bacterial and Mycotic Disease Section advantage of such products is that they oj the Animal Disease and Parasite Re- eliminate any possibility of spreading search Branch. Following graduation from the disease and accidentally infecting the College of Veterinary Medicine^ the the veterinarian while vaccinating the State College of Washington^ he was in swine. These bacterins show consider- charge of the Federal Bang''s Disease Labo- able promise as additional tools for ratory at Oregon State College in Corvallis. the control of swine erysipelas. Since ig^y Dr. Shuman has studied diseases No vaccination procedure offers of swine, principally swine erysipelas and complete protection in all circum- atrophie rhinitis. stances, however, and it is a common O. L. OsTEEN received the degree of mistake to think that they do. doctor of veterinary medicine from the Uni- versity of Georgia in ig28. He has been in AN OWNER can do much to prevent the service of the Department of Agriculture disease by following established princi- since ig32. He served in meat inspection for ples: Inspect his animals regularly; j years and has engaged in research work learn as much as possible about the on equine infectious anemia^ swine erysipelas, health of animals and the conditions equine encephalomyelitis, Newcastle disease, on the premises where replacement and vesicular diseases.

Diseases of Baby Pigs

N. R. ELLIS AND RICHARD D. SHUMAN

NEARLY one-third of all pigs born infections, parasites, numbers of pigs each year die from various disorders per litter, and others. and hazards. The multiple nature of the causes is Not all of the loss can be said to be evident in the cataloging of deaths out- due to diseases in the strict sense. The wardly apparent as due to mashing or causes, which often are ill-defined and injury. Many of the deaths are en- overlapping, include various manage- tirely physical. They are caused by ment factors that involve housing, fa- the sow and often indirectly by inade- cilities, and care; various prenatal fac- quate housing and lack of protective tors, which invoive several variables guardrails, brooder lamps, and other such as genetics, physiology, disease pen facilities, of which the undersized, organisms, and nutrition; and post- weak, and sick pigs are more prone to natal factors reflected in physiological become victims. well-being of dam and pig, nutrition, The reasons why they are under-