STRANGLES, INFECTIOUS RHINO-ADENITIS.
Synonyms. Definition. Historic notes. Bacteriology: streptococcus coryzæ contagiosæ equi in pus, chains of 3 and upward, free cocci, arthrospores, clumps, ærobic, growing freely in serum, or glycerined bouillon; pathogenic to horse and white mouse; relation to other streptococci; clinical evidence; accessory causes, youth, primary susceptibility, dentition, training, impure stable air, grain ration, excitement, sudation, fatigue, chill, change of climate, trading, crowding, sea voyage, catarrh of air passages. Infecting products, pus, ingesta, blood, manure, fodder, litter, water, secretion of mucosa of healthy. Wounds, castration, mangers, racks, troughs, buckets, poles, shafts, harness, halters, twitches, blankets, rubbers, combs, brushes, men, etc. Pathology: infection of lymphatics, through inhalation, sore, ingestion, congenital, milk; congestion of nasal mucosa, epithelial degeneration and desquamation, discharge little viscid, corded lymphatics rare, submaxillary swelling rarely small or nodular, pus creamy, indolent cases, pharyngeal, thoracic, buccal, gastro-intestinal, hepatic, pancreatic, splenic, muscular, arthritic, cutaneous, nervous. Forms: mild, malignant, regular, irregular. Incubation 3 to 5 days. General symptoms: hyperthermia, dulness, apathy, costiveness. Specific symptoms: nasal, congestion, sneezing, purulent discharge; epiphora, submaxillary phlegmon; pharyngeal and laryngeal; parotidean; pulmonary; abdominal, hepatic, pancreatic, splenic, perirenal, cutaneous, genital, nervous, septicæmic. Diagnosis, from catarrh, glanders. Prognosis, favorable, apart from malignancy. Prevention: exclude strange equine animals; avoid public stables, yards, drinking troughs and buckets; also manure, stable utensils, hay, fodder, litter, or watershed from infected places; disinfect cars, wagons, etc. Seclude inmates of infected stable, yard, park, etc., temporarily close public drinking and feeding places, make sale or exposure of infected animal penal; temporarily close dealers’ stables; sale with general guarantee only. Disinfection. Immunization; inoculation from mild case. Treatment: hygienic, antipyretic, eliminating, antiseptic, surgical, tonic, antisuppurant.
Synonyms. Distemper; Coryza Contagiosa Equorum; Gourme (Fr.); Druse (Ger.); Cimurro (Ital.).
Definition. An infective, streptococcic, febrile disease of solipeds, usually manifested by a catarrhal inflammation of the upper air passages, and phlegmon of the adjacent lymph glands, or less frequently by phlegmonous inflammation of lymph glands elsewhere or of the skin.
Historic Notes. Strangles was fairly indicated in the writings of the ancient Greek veterinarians, and was clearly described and attributed to contagion by Solleysel in 1664. It was so evidently infectious that it was experimentally inoculated by Lafosse in 1790, by Viborg, in 1802, and later, by Erdelyi (1813) and Toggia (1823) and others. Rivolta, in 1873, found a streptococcus in the pus of its abscesses, and to this the contagion was definitely assigned by Baruchello (1887), Schütz, Sand and Jensen (1888). Priority in this demonstration is accorded to Schütz.
Bacteriology. The streptococcus coryzæ contagiosæ Equi (Streptococcus rhino-adenitis or S. equi) is easily found in the pus of gland abscesses sometimes in pure cultures (impure in the nasal discharge), stains readily in aniline colors and in Gram’s solution so that it stands out clearly among the pus cells. The decolorizing agent must be weak (not muriatic acid) and applied only for a very short time. Beside the chain forms, there are isolated, oval cocci, some of which, larger than others and more elongated, have been held to be arthrospores or mother cells. The number of elements articulated in a chain varies from two to four and upward. The chains are straight or sinuous, and may be grouped in bundles, radiating masses, or clumps like staphylococci.
They are ærobic (facultative anærobic), grow freely as transparent droplets on blood serum at 99° F., and in glycerine bouillon, and less vigorously on agar and gelatine. On agar the colonies reach the size of a pin head in two days with projecting alæ, and on gelatine in three to five days, and then dry and shrink. Multiplication takes place by transverse division, and at such a time the organism may seem to be a chain of diplococci.
Pathogenesis. Inoculation of cultures on a susceptible horse produces the unquestionable phenomena of strangles, and solipeds alone take the disease casually. In white mice it produces abscess in the seat of puncture and in the adjacent lymph glands. If the action is delayed the abscess may be in lung, spleen, kidneys, liver, or other distant organ. Rabbits, Guinea pigs, pigeons, pigs and cattle are immune unless large doses are employed. Intravenously large doses kill the lamb.
The identity of the microbe with other streptococci of animals and man has been claimed. Arloing alleges that, by culture of the microbe in the blood or peritoneum of the live rabbit, he exalted the virulence, and obtained in succession a streptococcus capable of producing erysipelas; gangrenous erysipelas; suppurating, sloughing erysipelas; pseudo-membranous peritonitis; metastatic abscesses; and fulminant septic peritonitis. Hill, Jensen and Sand, and Lignieres, as the result of cultures and inoculations claim that strangles streptococcus is identical with that of contagious pneumonia. Courmont, on the other hand, as the result of his cultures and inoculations, concludes that the microbe of strangles and that of erysipelas are independent organisms.
The clinical evidence is decidedly against the theory of identity. In epizoötics of strangles we meet with a constant succession of cases of strangles and in districts into which contagious pneumonia has never been introduced, no single case of that disease ever comes in to break the monotony of the sequence and to start a series of cases of the latter affection. Conversely, in an outbreak of contagious pneumonia in a locality heretofore free from strangles, strangles do not develop. Again, no matter how prevalent nor how constant strangles may be in a locality, and how habitually men have their wounded hands covered with the pus of the abscesses, no epidemic of erysipelas is entailed in man. Strangles spreads with remarkable rapidity through a stable, but not to the often more than equally exposed human attendants, nor to any animal apart from the genus equus. The absence of strangles from Iceland (Jonsson) endorses that view.