Ganho de peso, consumo de ração e histologia de órgãos de leitões alimentados com rações contendo baixos níveis de fumonisina B1

Abstract

RESUMO.-A fumonisina B 1 (FB 1 ) é um metabólito secundário produzido principalmente por Fusarium verticilioides em diversos tipos de alimentos, principalmente o milho, o qual constitui a base para composição de rações para várias espécies de animais domésticos. A FB 1 é particularmente tóxica para suínos, cujas manifestações clínicas são evidentes em animais expostos a altas concentrações de FB 1 na ração (em geral, acima de 30mg/kg). No entanto, são escassos os estudos sobre os efeitos da FB 1 em suínos alimentados com rações contendo baixas concentrações de fumonisinas, as quais são mais prováveis de serem encontradas em condições de campo. O objetivo do estudo foi avaliar os efeitos da exposição de leitões a baixos níveis de FB 1 na ra- ) is a secondary metabolite produced mainly by Fusarium verticilioides in several types of foods, particularly corn, which is the basis for composition of feed for several domestic animals. FB 1 is particularly toxic to pigs, being the clinical manifestations evident in animals exposed to high concentrations of FB 1 in the diet (generally above 30mg/kg). However, there are few studies on the effects of FB 1 on pigs fed rations containing low concentrations of fumonisin, which are most probably found under field conditions. The aim of the study was to evaluate the effects of a 28-day exposure of piglets to low levels of FB 1 in the feed on the weight gain, feed consumption, organ weights and histological aspects of the spleen, liver, lungs, kidneys and heart. Twenty-four pigs were assigned into 4 experimental groups and fed diets containing 0mg (control), 3.0mg, 6.0mg or 9.0mg FB 1 /kg diet. The different diets did not affect (P>0.05) the weight gain or the weight of organs examined. There were no macroscopic or histological lesions in the spleen, liver, kidneys and heart. However, histological lesions were found in the lungs from all animals fed rations containing fumonisin, hence indicating that none of the FB 1 levels used in the experiment could be considered as safe for piglets. Further studies on the mechanisms of toxic action of FB 1 in pigs are needed, particularly under conditions of prolonged exposure to low contamination levels in the diet.INDEX TERMS: Fumonisin B 1 , FB 1 , low levels, swine, toxic effects, mycotoxicosis.

Porcine Hepatic Response to Fumonisin B1 in a Short Exposure Period: Fatty Acid Profile and Clinical Investigations

“…In our setting, FB 1 did not affect the kidney weight, which is interesting since its elimination happens via renal filtration [14], and partly through feces. Our results are in full agreement with the study of Souto et al [37] and partially with results of Andretta et al [40], in which FBs did not affect the weight of the kidney, spleen, and heart, but increased the relative weight of the liver and lung. The probable weight alteration of the liver was based on the hypothesis that FB 1 provides slight hepatotoxicity in swine and rats [12,25].…”

“…Regarding the body weight gain and feed consumption, similar results to our findings were observed in weaned piglets fed 10, 20, and 40 mg/kg FB 1 for four weeks [15]. Furthermore, 9 mg FB 1 /piglet/day for four weeks did not induce alteration in the production performance: growth, organ weights, and feed intake [10,37]. FB 1 at 10–15 mg/kg diet is able to delay the piglet sexual maturity during longer exposure period at 24 weeks [38].…”

Risks for animal health related to the presence of fumonisins, their modified forms and hidden forms in feed

“…Pigs fed for 42 days with 30 mg FB 1 /kg feed, and with 50 and 100 mg FB 1 /kg feed for 22, 5 and 10 days, respectively, had enlarged, friable, pale, yellowish liver, visible discoloration (fibrosis), vacuolation and necrosis (including occasional single cell necrosis) of the liver (Fodor et al., ; Piva et al., ). Other studies showed increase in liver weight at 1.5 and 30 mg FB 1 /kg feed (Piva et al., ; Lessard et al., ; Lalles et al., ), polyploidy and fatty change in the liver at 12 mg FB 1 /kg feed (Moreno Ramos et al., ) but no macroscopic or histological lesions in the liver and other organs (spleen, kidneys and heart) at 3.0, 6.0 or 9.0 mg FB 1 /kg diet and 28 days of exposure (Souto et al., ).…”

“…Pulmonary oedema is observed in animals exposed to low (3–10 mg FB 1 /kg feed) and high (20–100 mg FB 1 /kg feed) concentrations of fumonisins although with different degrees of severity. Histological lesions were observed in the lungs from all piglets fed diets containing low concentrations as for example 3, 6 and 9 mg FB 1 /kg feed (Grenier et al., ; Souto et al., ) for 35 and 28 days respectively, whereas the exposure to 12 mg FB 1 /kg feed of FB 1 for 18 days produced slight interstitial pneumonia and only one pig showed severe haemorrhagic congestion and some oedema (Moreno Ramos et al., ). In two studies performed by Zomborszky‐Kovács et al.…”