Activated carbons as potentially useful non-nutritive additives to prevent the effect of fumonisin B1 on sodium bentonite activity against chronic aflatoxicosis.

Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.

Effects of long-term cyanide ingestion by pigs.

Animal performance and health status are adversely affected by long-term cyanide ingestion; however, the effects of cyanide ingestion by pigs have not been fully determined. The aim of the present study was to determine the effects of prolonged exposure to different doses of potassium cyanide (KCN) in growing-finishing swine. Twenty-four pigs, 45 days of age, were divided into four equal groups and treated with different doses of KCN: 0, 2.0, 4.0 or 6.0 mg per kg body weight per day for 70 consecutive days. The results showed a significant alteration in thiocyanate, creatinine and urea levels and in alanine aminotransferase activity of swine dosed with 4.0 and 6.0 mg/kg/KCN. Thyroid weight was significantly increased in those pigs from 4.0 mg/kg KCN group, but no change in cholesterol, triiodothyronine or thyroline levels were observed. Body and carcase weights, body weight gain, and bacon thickness were not affected by KCN treatment. The histopathological study revealed increased numbers of vacuoles in the colloid of thyroid follicles, degeneration of cerebellar white matter and Purkinje cells, degeneration of renal tubular epithelial cells, caryolysis and pyknosis in hepatocytes, and disturbance of the normal lobular architecture of the liver in all treated pigs. Thus, long-term administration of KCN to swine affects several tissues and could adversely affect animal production.

Focal symmetrical encephalomalacia in swine from ingestion of Aeschynomene indica seeds.

A spontaneous outbreak of neurological disease in swine caused by the ingestion of Aeschynomene indica seeds and reproduction of the disease in the same specie are reported. In the natural outbreak the morbidity, mortality and lethality rates were respectively 25%-40%, 8.5%-20%, and 25%-66%. Clinical signs were variable degrees of incoordination of gait, falls, sternal recumbency with wide base stance of the hind limbs, lateral recumbency and death. For experimental reproduction of the intoxication, 5 (A-E) pigs were fed a ration containing 10% (PigA), 15% (Pig B) and 20% (Pigs C-E) of A. indica seeds. Pigs A and B were euthanatized and Pigs C-E died of acute disease respectively 16, 21 and 24 hours after the start of the experiment. Clinical signs were similar to those observed in pigs from the spontaneous outbreak. Histopathological findings in the brain of pigs fed rations with 20% A. indica seeds (C-E) were congestion, edema and hemorrhage and swollen capillary endothelia in nuclei and in the telencephalic cortex. Pigs fed 10% and 15% A. indica had histopathological changes in the brain of discrete focal symmetrical areas of malacia. These findings indicate that one or more toxic principles in A. indica seeds are responsible for this neurological condition and that clinical outcome and pathological changes are dose-dependent. The symmetrical malacic foci from the ingestion of A. indica seeds in pigs affected vestibular and cerebellar nuclei, putamen, and the mesencephalic substantia nigra, oculomotor, and red nucleus; thus, focal symmetrical encephalomalacia is suggested as a better name for the disease.

Tiamulin-nitrovin interaction in pigs: a case report and experimental reproduction.

Tiamulin is a diterpenic veterinary drug widely used in swine for the control of infectious diseases, including swine dysentery and enzootic pneumonia. Tiamulin is well tolerated and only a few drug interactions have been reported with some ionophore antibiotics. A case of tiamulin adverse drug interaction with nitrovin, a nitrofuranic growth promoter, in fattening pigs from a commercial farm is described. To confirm the diagnosis, experimental reproduction was conducted using 20 healthy female pigs. The animals were randomly divided into 4 groups: 1 of them receiving feed medicated with 100 mg tiamulin hydrogen fumarate/kg, another received 20 mg nitrovin/kg to establish the harmlessness of the drugs alone. The other 2 groups received feeds containing both drugs at the previous concentrations, one of which came from the farm. In the last 2 groups clinical signs appeared 72-96 h after initially feeding pigs the tiamulin hydrogen fumarate + nitrovin-containing feed. The animals had uneasiness, anxiety, skin erythema, and rash on snout, vulva and abdomen, and increased body temperatures. No mortality occurred, and there were no characteristic findings during pathological examination. The signs disappeared after 96 h of consuming the medicated feed, leaving a slight skin thickening of the affected regions. All signs disappeared spontaneously 4-5 d after ceasing medication.

Surto de intoxicação por narasina em suínos / An outbreak of narasin poisoning in swine

Descreve-se um surto de intoxicação por narasina em suínos, cujo diagnóstico baseou-se no histórico, quadro clínico-patológico, na reprodução da enfermidade pela experimentação com a ração comercial originalmente oferecida aos suínos, bem como pelo exame químico posterior que detectou narasina em quantidades suficientemente elevadas para causar intoxicação. Apesar de os quadros clínico-patológicos das intoxicações natural e experimental serem da mesma natureza, houve algumas diferenças. Nos casos naturais o índice de letalidade foi elevado, enquanto que na intoxicação experimental nenhum animal morreu. Os exames histopatológicos revelaram, em parte dos casos naturais, além das lesões dos músculos estriados, também lesões nas fibras musculares cardíacas, últimas não verificadas nos casos experimentais. Sugere-se que essas diferenças poderiam ser explicadas pelo estresse ao qual os animais eram submetidos na granja pelo grande número de animais nas baias, ao contrário dos animais experimentais que eram mantidos em compartimentos individuais

Pasteurella multocida fimbriada como agente desencadenante de pleuritis y neumonía fibrinosa en cerdos / Fimbriated Pasteurella multocida as etiological agent of pleuritis and fibrinous pneumonia in pigs

Pasteurella multocida tiene cuatro diferentes tipos capsulares (A, B, D y E); A y D son los que caudan problemas en cerdos. El tipo A causa neumonía y el D, rinitis; este tipo capsular produce tpxona, que destruye los cornetes nasales. En 1983, se aislaron dos cepas de P. multocida tipo A en dos granjas con problemas respiratorios, como pleuritis, pericarditis, neumonía fibrinosa y pequeños abscesos. Estas cepas de P. multocida se identificaron con A52 y A59, las que se observaron también al microscopio electrónico observándose pequeñas microvellocidades en la superificie. En inoculaciones experimentales con estos tipos, en relación con los que normalmente ocasionan problemas respiratorios en cerdos, se observó que tales cepas desencadenan problemas más severos de tipo pleuroneumónico abscedativo.

The poison center as a reservoir for antidotes for veterinary poisoning emergencies.

Animal poisonings account for a significant number of the cases responded to by poison centers. The majority of consultations involve small animals and do not necessitate the use of large amounts of pharmacologic antagonists, such as atropine to treat anticholinesterase pesticide poisonings. However, large animals such as cattle present unique management problems, since phenomenal amounts of antidotes may be needed to treat a herd of cattle, creating a significant economic impact. The most challenging dilemma is providing 24-h availability and a means of acquisition of sufficient quantities of antidotes to reduce the economic impact of large-animal poisonings. In conjunction with a state veterinary medical association, a RPIC serves as a depot for the storage and distribution of emergency veterinary antidotes. Sufficient quantities of atropine, methylene blue, calcium EDTA, sodium nitrite and thiosulfate, and activated charcoal are available via the RPIC to treat a herd of 200 cattle. The antidotes are available only for emergency treatment and with a veterinary prescription. The 24-h nature of the poison center makes it an ideal location to serve the needs of veterinarians.

A case of solanum malacoxylon toxicity in pigs.

The postmortem and histological changes seen in the kidneys, lungs and vascular system in spontaneous Solanum malacoxylon poisoning on a pig farm in Buenos Aires Province, Argentina, are reported. Macroscopic calcified plaques in the endocardium, aorta, and pulmonary artery and mineralization in renal pelvis were observed. Microscopic examinations revealed tubulonephrosis and calcification of the elastic fibers of kidney vessels. Severe calcinosis of the endocardium and elastic fibers of arteries (aorta, pulmonary, renal) were seen. In the lung, calcification of the elastic fibers of the alveolar wall and the lamina propia of the bronchia were also noted.