The effects of mycotoxin deoxynivalenol (DON) on haematological and biochemical parameters and selected parameters of oxidative stress in piglets.

OBJECTIVES: Deoxynivalenol (DON) - trichothecene mycotoxin, is frequently detected in high concentrations in cereals in the temperate region of Europe. The aim of this study was to determine the effect of DON in feed on haematological and biochemical parameters and on oxidative stress in piglets. METHODS: Two concentrations of DON in feedstuff for pigs were chosen: 0.6 mg/kg (group C) and 2.0 mg/kg (group M). Twelve weaned pigs were used in each group. Pigs were fed with naturally contaminated feed for 4 weeks. On days 14, 21 and at the end of the experiment (day 28) samples of blood were taken to determine haematological parameters, plasma biochemical parameters, ceruloplasmin activity and FRAP (ferric reducing ability of plasma). RESULTS: The haematological variables did not show changes in response to contaminated diet with exception of the mean corpuscular volume, which was significantly decreased at the end of the experiment in the group M. A significant increase of alkaline phosphatase activity (140%, p<0.01) was found in the group M compared to the group C at the end of the experiment. A significant decrease was found on the day 21 in FRAP (85%, p<0.001) and on the day 28 in ceruloplasmin (75%, p<0.01) in the group M compared to the group C. CONCLUSIONS: The decrease of FRAP and ceruloplasmin indicate a lowered ability of organism to scavenge reactive oxygen species. The higher concentration of DON in feedstuffs had a negative influence on the antioxidant ability of piglet's plasma.

The impact of high iodine intake on thyroid function in ewes and lambs.

OBJECTIVES: The objective of the study was to assess the metabolic risk of excessive dietary iodine intake in ewes and neonatal lambs. DESIGN: Pregnant Sumava ewes received an experimental diet containing 3.1 mg iodine per kg of dietary dry matter in Group A (control, n=13, 6 ewes and 7 lambs) and 5.1 mg iodine per kg of dietary dry matter in Group B (experimental, n=12, 6 ewes, 6 lambs) for eight months. Iodine was administered to ewes as calcium iodate. TSH in blood serum; TT3, TT4, fT3, and fT4 in blood plasma were examined in both groups of ewes and lambs to assess the risks of iodine intake above the permitted limit, as it applies to thyroid gland activity. RESULTS: Group B ewes showed a significant increase in TSH and TT4 only on day 1 after parturition. The highest values of TT4, TT3, and fT3 in lambs were recorded on day 1 after birth. The lowest values of fT3 and fT4 in lambs were measured on day 60 after birth with no differences observed between the groups. In lambs of Group B the lower concentration of TSH until day 3 after birth was followed by a significant increase from day 10 after birth. CONCLUSION: Our results indicate a risk of postnatal hypothyroidism among lambs from pregnant and lactating ewes having a high iodine intake.

Utilisation of iodine from different sources by sows and their progeny.

OBJECTIVES: The aim of the study was to compare iodine utilization from different sources by sows and their progeny and the levels of T3 and T4 in their serum. DESIGN: Pregnant Czech Large White × Landrace sows were fed with an experimental KPK diet (a diet for lactating sows) 14 days before parturition until weaning (at a piglet age of 28 days). In group A (n=50, 10 sows, 40 piglets) the feed was supplemented with KI (0.6 mg of iodine per kg of feed). Iodine enriched alga Chlorella spp. (0.6 mg of iodine per kg of feed) was used as a supplement in group B (n=50, 10 sows, 40 piglets). In group C (n=50, 10 sows, 40 piglets) the sows were injected i.m. with IFAE at a dose of 100 mg of iodine per sow. Iodine, T3 and T4 were measured in each group for comparison of iodine utilization. RESULTS: The use of IFAE resulted in higher serum concentrations in sows compared to KI and alga. In contrast, iodine concentrations in milk and piglets were lower when IFAE were used. We found a wide variation in the concentrations of T3 and T4 in the serum of piglets in all groups. CONCLUSION: Our results indicate a good utilization of iodized oil by sows. However, its transfer into milk is lower compared to the other iodine sources.

Effects of high dietary levels of Se-enriched yeast on tissues selenium content and meat quality traits - a model study in rats.

OBJECTIVES: The aim of the trial was to evaluate effects of high dietary levels of Se-enriched yeast on selenium concentrations in muscle and liver tissue and on the meat quality traits in rats. DESIGN: The experimental feed mixtures were fed to Wistar Albino rats for a period of 10 weeks. They differed in the dose and in the form of Se supplement. Supplemental dose of 0.3 mg.kg-1 of Se per one kilogram of feed was used in group I (n = 10, sodium selenite) and in group II (n = 10, Se-enriched yeast). Elevated dose 2 mg.kg-1 Se per one kilogram of feed was used in group III (n = 10, sodium selenite) and in group IV (n = 10, Se-enriched yeast). RESULTS: The use of elevated dietary Se level (2 mg.kg-1) in the form of sodium selenite did not increase lipid oxidation (malondialdehyde content) in muscles nor influenced meat quality traits. The use of elevated dietary Se level in the form of Se-enriched yeast resulted in higher Se muscle concentrations accompanied by increased of malondialdehyde content. The meat quality traits remained unaffected. CONCLUSION: High selenium concentrations in muscle produced by Se-enriched yeast were accompanied by elevated MDA levels, but it did not negatively influence meat quality traits.

Evaluation of selenium status in pure bred duroc sows and their progeny.

OBJECTIVES: The aim of this trial was to determine selenium status in pure bred duroc sows and their progeny and to compare it to Czech Large White x Landrace breed. DESIGN: The pregnant duroc sows (n=12) and pregnant Czech Large White x Landrace sows (n=12) were fed identical diets supplemented with sodium selenite. RESULTS: During lactation significantly higher serum Se concentrations (p<0.001) were found in duroc piglets. Also significantly higher serum GSH-Px activities (p<0.001) were found in duroc sows and piglets. No differences in concentrations of Se in colostrums and milk were found between the two breeds. CONCLUSION: Our findings support the hypothesis that there may be breed differences in indices of selenium status in pigs.