Diagnosis and Treatment of Swine Dysentery (Part 2): Detailed Explanation of Symptom Identification and Treatment Methods

4 Laboratory Testing

4.1 Smears were made from the heart, blood, liver and spleen of dead pigs, stained with Gram stain and Rui's stain, and no bacteria were found under microscopic examination.

4.2 Mucus-containing bloody feces from acutely affected pigs were collected and mixed with an equal amount of normal saline to prepare a suspension. The suspension was examined under a dark-field microscope, and in multiple fields of view, 3-5 spirochetes with uniform morphology, pointed ends at both ends, and snake-like motility were visible.

5 Prevention and Control

5.1 For the whole herd, use mequindox (3-methyl-2-acetyl-quinoline-1,4-dioxide), adding 50 g of mequindox per 10 kg of feed, with 3 days as one treatment course;

5.2 For affected pigs, inject 0.5% mequindox intramuscularly at 5 mg/kg body weight, 2 times/day, for 3 consecutive days; add compound vitamin B powder to the feed; for weak animals, inject vitamin K3 and vitamin B12 intramuscularly; for those with severe diarrhea, perform intraperitoneal fluid replacement with glucose saline, and inject adrenaline intramuscularly for cardiac support and symptomatic treatment.

5.3 Isolate affected pigs and strengthen feeding management, pay attention to cold prevention and warmth preservation, improve sanitation, and strictly implement an all-in-all-out single rearing system to prevent the spread of the epidemic to the breeding pig and suckling/nursery pig areas.

5.4 Formulate a rodent prevention and extermination plan, and carry out centralized harmless treatment of feces. After adopting the above measures, the condition was quickly brought under control. On the 3rd day after medication, of the 67 severely ill pigs, apart from 2 deaths, the rest gradually returned to normal.

6 Summary and Experience

6.1 Based on the incidence situation, clinical symptoms, necropsy lesions, laboratory testing and treatment observation, it was diagnosed as swine dysentery caused by Treponema hyodysenteriae??/p>

6.2 The outbreak of dysentery in growing-finishing pigs on this pig farm was mainly caused by the usual focus of work being placed on breeding pigs and suckling/nursery pigs, while neglecting the management of carrier growing-finishing pigs, combined with sudden climate changes, poor cold prevention and warmth preservation, and poor feeding management.

6.3 For affected pig farms, control and purification measures for swine dysentery should be formulated immediately, with emphasis on strengthening drug prevention and treatment, feeding management, and rodent prevention and extermination, so as to achieve significant results.