Diagnosis and Treatment Report of Swine Gibberella Toxin Poisoning Cases

In November 2003, at a certain @#@227@#@ farm in Xinyang City, feeding moldy corn caused more than 300 pigs to fall ill successively, with a total of two deaths. Among them were more than 180 weaned piglets, more than 140 nursery pigs, and 36 replacement gilts. Treatment with sulfadiazine was tried first, followed by oxytetracycline, but neither was effective. The diagnosis was Gibberella toxin poisoning. The diagnosis and treatment situation is reported as follows:

1 Clinical symptoms

The affected pigs mainly showed reduced appetite or complete loss of appetite, normal or slightly elevated body temperature, extensive flushing of the skin in some pigs, and diarrhea in a few pigs. Symptoms in young gilts were relatively typical, with mammary gland hyperplasia, and swelling, flushing, and obvious protrusion of the vulva; in severe cases, the labia opened, the vaginal mucosa swelled, and secretions mixed with blood flowed out. However, none of the young gilts showed signs of estrus. In castrated male pigs, the prepuce was edematous and the mammary glands were enlarged; two pigs had rectal prolapse, with severe edema and hemorrhage of the intestinal mucosa. Parous sows, pregnant sows, and breeding boars showed no obvious symptoms, which may be related to the short duration of feeding moldy feed and the stronger resistance of these pigs.

2 Pathological changes

Necropsy of two dead young gilts showed congestion and swelling of the vaginal mucosa, with mucous exudate, edema of the cervical wall and myometrium, and ovarian hypoplasia. No other grossly visible lesions were found.

3 Diagnosis

3.1 Sensory examination The corn had a moldy odor, and some kernels had turned brown in color.

3.2 Culture Corn samples were soaked in 95% alcohol for two minutes, then inoculated onto Czapek plate medium and potato dextrose agar, and cultured in a mold incubator at 25°C for 48-72 hours. On both media, the mycelium grew vigorously. Cultures were picked and smeared, stained with lactophenol cotton blue, and examined under the microscope, showing obvious hyphae and spores. The hyphae were septate; the macroconidia were nearly sickle-shaped, gradually tapering at the tip, with 3-6 septa; the microconidia were oval and spindle-shaped, with a few having 1-3 septa. The number of microconidia was greater than that of macroconidia.

3.3 Animal test The abdominal hair of healthy rabbits was clipped over an area about 6 cm in diameter. Without damaging the skin, a cotton ball dipped in an ether-extracted concentrated liquid of the pure culture was applied several times to the clipped area. On the 5th day, the skin showed thickening, redness, and swelling, and two days later gradually became necrotic and scabbed.

Based on the above results, the diagnosis was swine Gibberella toxin poisoning.

4 Treatment. First, stop feeding the moldy corn and switch to high-quality corn, allow the pigs free access to sugar-salt water, and increase feeding of green, succulent feed. For severely affected pigs, use 200-500 ml of 10% glucose injection, 10-20 ml of vitamin C, and 5-10 ml of vitamin B1, mixed and injected intravenously at one time, once daily for 5 consecutive days. With the above measures, the condition was brought under control in 10 days, and the pigs recovered after two weeks.

5 Discussion

In general, Gibberella toxin poisoning occurs mainly in equines, but pigs can also be poisoned. Zearalenone in the toxin, as a kind of estrogen-like substance, can cause functional and morphological changes in the reproductive organs of pigs. To prevent the occurrence of this disease, the main measures are to prevent feed from becoming moldy and to detoxify moldy feed promptly.