Roland Pósa

Absorption, distribution and elimination of fumonisin B1 metabolites in weaned piglets

The absorption, distribution and elimination of fumonisin B1 (and B2) after oral administration of Fusarium verticillioides (MRC 826) fungal culture, mixed into the experimental feed for 10 days, was studied in weaned barrows. In order to determine the absorption of FB1 from the feed marked by chromium oxide, a special T-cannula was implanted into the distal part of pigs’ ileum. During the feeding of toxin-containing diet (45 mg FB1 kg−1) and until the tenth day after the end of treatment, the total quantity of urine and faeces was collected and their toxin content analysed. At the end of the trial, samples of lung, liver, kidney, brain, muscle, and fat were also collected and their fumonisin content analysed by LC-MS. The fumonisins appeared to decrease the reduced glutathione content in blood plasma and red blood cell haemolysate, possibly associated with in vivo lipid peroxidation. From a data set of 80 individual data and the concentration and rate of C r and fumonisins (FB1, partially hydrolysed FB1 and aminopentol) in the chymus, it could be established that the accumulative absorption of fumonisin B1 was 3.9% ± 0.7%. In the chymus, the FB1 conversions into aminopentol and partially hydrolysed FB1 were 1.0 and 3.9%, respectively. The degree of metabolism in faeces was variable, although the main product was the partially hydrolysed form, with very small amounts of the aminopentol moiety being recovered. In the investigated tissues the FB1 conversion to aminopentol and partially hydrolysed FB1 was 30 and 20%, respectively.

Use of Computed Tomography and Histopathologic Review for Lung Lesions Produced by the Interaction Between Mycoplasma hyopneumoniae and Fumonisin Mycotoxins in Pigs

Mycoplasma hyopneumoniae has a primary role in the porcine respiratory disease complex (PRDC). The objective of this study was to determine whether fumonisin mycotoxins influence the character and/or the severity of pathological processes induced in the lungs of pigs by Mycoplasma hyopneumoniae. Four groups of pigs (n = 7/group) were used, one fed 20 ppm fumonisin B1 (FB1) from 16 days of age (group F), one only infected with M. hyopneumoniae on study day 30 (group M), and a group fed FB1 and infected with M. hyopneumoniae (group MF), along with an untreated control group (group C). Computed tomography (CT) scans of infected pigs (M and MF) on study day 44 demonstrated lesions extending to the cranial and middle or in the cranial third of the caudal lobe of the lungs. The CT images obtained on study day 58 showed similar but milder lesions in 5 animals from group M, whereas lungs from 2 pigs in group MF appeared progressively worse. The evolution of average pulmonary density calculated from combined pixel frequency values, as measured by quantitative CT, was significantly influenced by the treatment and the age of the animals. The most characteristic histopathologic lesion in FB1-treated pigs was pulmonary edema, whereas the pathomorphological changes in Mycoplasma-infected pigs were consistent with catarrhal bronchointerstitial pneumonia. FB1 aggravated the progression of infection, as demonstrated by severe illness requiring euthanasia observed in 1 pig and evidence of progressive pathology in 2 pigs (group MF) between study days 44 and 58.

A comparative pathological finding in pigs exposed to fumonisin B1 and/or Mycoplasma hyopneumoniae

A more complicated pathology was observed in female pigs infected with Mycoplasma hyopneumoniae, when the same were exposed to 20 ppm dietary levels of fumonisin B1 (FB1) starting 14 days before infection for a period of 42 days as was assessed by gross pathology and pathomorphological examinations or computed tomography, and also manifested by the strong deterioration of the pneumonic process in two pigs and the subsequent euthanizing of one pig. Typical damages in FB1-fed pigs were a strong oedema in the lung and slight oedema in the other internal organs and mild degenerative changes in the kidneys, whereas the typical pathomorphological changes in M. hyopneumoniae-infected pigs corresponded to the morphologic pattern of a catarrhal bronchointerstitial pneumonia more pronounced in the cranial and middle lobes or in the cranial third of the caudal lobe of the lung. The pigs treated by both pathogens (toxic and infectious) revealed strong oedematous changes in the interstitium of lung in addition to deteriorated and extended bronchointerstitial pneumonic process.

Quantitative PCR with 16S rRNA-gene-targeted specific primers for analysis of caecal microbial community in growing rabbits after dietary supplementation of thyme (Thymus vulgaris) and spirulina (Arthrospira platensis)

Abstract Objective of this study was to evaluate the effect of supplementation of growing rabbits’ diet with 5% spirulina (Arthrospira platensis) and/or 3% (Thymus vulgaris L.), on composition and amount of rabbits caecal microbiota. After weaning, rabbits were randomly sorted to 4 groups (n = 42/group). The control group received a pellet without any supplementation, in treated groups the dietary supplementation was provided until 77 days of age. On 49, 63 and 77 days of age, six healthy animals/group were randomly selected and slaughtered. From the caecal content the amount of total bacteria, Bacteroides, Clostridium leptum and Clostridium coccoides were determined by quantitative polymerase chain reaction (qPCR), with the aid of bacterial ribosome coding DNA. The copy number of total bacteria, C. leptum, C. coccoides and Bacteroides varied between 2.75 × 1012 to 2.24 × 1013, 5.25 × 1011 to 1.82 × 1012, 2.5 × 1010 to 6.91 × 1011 and 5.89 × 1010 to 1.10 × 1012, respectively. The amount of investigated bacteria represented 0.6%-13.4% of the total bacteria. The use of spirulina and/or thyme supplements influenced the amount of the copy number of each bacteria examined between 49 and 77 days of age. Their effect on the total bacteria number was temporary. Spirulina resulted in more Bacteroides on day 63 but significantly lower amount of Clostridia at 63 and at 77 days of age. The antimicrobial effect of thyme on the absolute Clostridia number was temporary, prevailing on day 63. Thyme resulted in significantly decreasing percentage ratio (within total bacteria) of C. leptum and C. coccoides by 77 days of age.

Feed exposure to FB1 can aggravate pneumonic damages in pigs provoked by P. multocida

The possible interaction between Pasteurella multocida and the mycotoxin fumonisin B1 (FB1), recognised as one of the most often food/feed contaminant, was studied with the aim to evaluate whether and how FB1 can influence and/or complicate the development and severity of various pathological damages provoked by Pasteurella multocida in some internal organs of pigs. Heavier lung pathology was seen in pigs experimentally infected with Pasteurella multocida, when the same were exposed to 20ppm dietary levels of fumonisin B1 (FB1) as was assessed by gross pathology, pathomorphological examinations, clinical biochemistry and some immunological investigations. The most typical damages in FB1 treated pigs were the strong oedema in the lung and the slight oedema in the other internal organs and mild degenerative changes in the kidneys, whereas the typical pathomorphological findings in pigs infected with Pasteurella multocida was broncho-interstitial pneumonia. FB1 was found to aggravate pneumonic changes provoked by P. multocida in the cranial lobes of the lung and to complicate pneumonic damages with interstitial oedema in the lung. No macroscopic damages were observed in the pigs infected only with Pasteurella multocida. It can be concluded that the feed intake of FB1 in pigs may complicate or exacerbate the course of P. multocida serotype A infection.

Effect of Mycoplasma hyopneumoniae and fumonisin B1 toxin on the lung in pigs

Abstract The authors examined the combined effect of Mycoplasma hyopneumoniae (Mh) and fumonisin B1 (FB1) mycotoxin in pigs. Computed tomography (CT) was applied to follow up the pathological events in the lung. Piglets were infected with Mh, or treated with FB1, or both infected and treated with Mh and FB1. The Mh infection produced lung lesions in all piglets the severity of which was increased by FB1. The CT is a suitable method for studying the pathological conditions in the lower respiratory tract of swine.