T-2 toksin - pojavnost i toksičnost u peradi

T-2 toxin is the most toxic type A trichothecene mycotoxin. It is the secondary metabolite of the Fusarium fungi, and is common in grain and animal feed. Toxic effects have been shown both in experimental animals and in livestock. It has been implicated in several outbreaks of human mycotoxicoses. Toxic effects in poultry include inhibition of protein, DNA, and RNA synthesis, cytotoxicity, immunomodulation, cell lesions in the digestive tract, organs and skin, neural disturbances and low performance in poultry production (decreased weight gain, egg production, and hatchability). Concentrations of T-2 toxin in feed are usually low, and its immunosuppressive effects and secondary infections often make diagnosis difficult. If at the onset of the disease, a change in diet leads to health and performance improvements in animals, this may point to mycotoxin poisoning. Regular control of grain and feed samples is a valuable preventive measure, and it is accurate only if representative samples are tested. This article reviews the incidence and toxic effects of T-2 toxin in poultry.T-2 toksin je najtoksičniji predstavnik trikotecenskih mikotoksina tipa A. On je sekundarni produkt metabolizma plijesni roda Fusarium i često je prisutan u žitaricama i hrani za životinje. Štetni učinci uočeni su u eksperimentalnih životinja i životinja u uzgoju. On se povezuje s pojavom bolesti ljudi od mikotoksikoza. Učinci toksina u peradi su višestruki: inhibicija sinteze proteina, DNA i RNA, citotoksični učinak, imunomodulatorni učinak, oštećenje stanica probavnog sustava, organa i kože, živčani poremećaji te pad proizvodnih karakteristika u uzgoju peradi (slabiji prirast, pad nesivosti i valivosti). Koncentracije T-2 toksina u hrani redovito su vrlo malene, a zbog imunosupresivnog djelovanja toksina te istodobne sekundarne infekcije bolest se često teško dijagnosticira. Pri pojavi bolesti promjenom hrane može doći do poboljšanja zdravstvenog stanja, što tako|er upućuje na moguće trovanje mikotoksinima. Redovita kontrola uzoraka žitarica i hrane za životinje jedna je od preventivnih mjera, a detekcija mikotoksina u žitaricama i hrani pouzdana je samo ako se ispituje reprezentativan uzorak. U radu su opisani učestalost i toksični učinci T-2 toksina u peradi

An overlooked connection: serotonergic mediation of estrogen-related physiology and pathology

BACKGROUND: In humans, serotonin has typically been investigated as a neurotransmitter. However, serotonin also functions as a hormone across animal phyla, including those lacking an organized central nervous system. This hormonal action allows serotonin to have physiological consequences in systems outside the central nervous system. Fluctuations in estrogen levels over the lifespan and during ovarian cycles cause predictable changes in serotonin systems in female mammals. DISCUSSION: We hypothesize that some of the physiological effects attributed to estrogen may be a consequence of estrogen-related changes in serotonin efficacy and receptor distribution. Here, we integrate data from endocrinology, molecular biology, neuroscience, and epidemiology to propose that serotonin may mediate the effects of estrogen. In the central nervous system, estrogen influences pain transmission, headache, dizziness, nausea, and depression, all of which are known to be a consequence of serotonergic signaling. Outside of the central nervous system, estrogen produces changes in bone density, vascular function, and immune cell self-recognition and activation that are consistent with serotonin's effects. For breast cancer risk, our hypothesis predicts heretofore unexplained observations of the opposing effects of obesity pre- and post-menopause and the increase following treatment with hormone replacement therapy using medroxyprogesterone. SUMMARY: Serotonergic mediation of estrogen has important clinical implications and warrants further evaluation

The effects of cofactor and species differences on the in vitro metabolism of propiophenone and phenylacetone

In vitro metabolism of the aromatic ketone propiophenone and its nonaromatic isomer phenylacetone was studied using fortified 12 000 × g supernatants of liver homogenates from rat and rabbit. Reduction to the corresponding alcohols was the major metabolic route observed, although aliphatic C-hydroxylation and alcohol dehydrogenation also occurred. Marked differences were observed in the amounts of carbonyl reduction of the substrates, which was dependant on the species as well as the cofactor employed. Using rat liver preparation, phenylacetone was reduced to 1-phenyl-2-propanol much more efficiently with an NADH-fortified system than when NADPH was used whereas in rabbit, extensive reduction occurred in the presence of either cofactor. Reduction of propiophenone to 1-phenyl-1-propanol by rat liver preparation was slightly greater in the presence of NADH than with NADPH; the converse was observed in rabbit.Aliphatic hydroxylation of propiophenone to 2-hydroxy-1-phenyl-1-propamine was also a significant metabolic pathway in both species, with NADPH being the more efficient cofactor, but C-1 hydroxylation of phenylacetone to 1-hydroxy-1-phenyl-2-propanone occurred only to a minor extent. Small amounts of 1-phenyl-1,2-propanedione, as well as both erythro and threo isomers of 1-phenyl-1,2-propanediol, were also identified as metabolites in both species. Similar metabolic studies were carried out on the alcohols 1-phenyl-1-propanol and 1-phenyl-2-propanol and again the nature and quantities of metabolites isolated showed both species and cofactor dependancies. </jats:p

EFFECTS OF FEEDING DEOXYNIVALENOL (DON)-CONTAMINATED WHEAT DIETS TO PREGNANT AND LACTATING GILTS AND ON THEIR PROGENY

Thirty-six gilts were bred and given 2 kg feed daily through pregnancy. Three diets were used, one a control (C) containing 70% clean wheat, another (M) containing 35% clean and 35% DON-contaminated wheat and the third (H) containing 70% DON-contaminated wheat. The DON content of the diets was 0.2, 3.8 and 6.2 mg kg−1 respectively. Six of the gilts (1C, 2M, 3H) were found to be nonpregnant and one (M) was removed because of lameness. Of the 29 that farrowed five (2C, 1M, 2H) would not eat; the remaining 24 gilts completed a 21-d lactation. The diets were offered up to a maximum of 5 kg daily during lactation. Body weight data for pregnancy and lactation showed no evidence of a dietary effect. Body weight, length (crown to rump) and carcass composition of the piglets did not show any effects of the DON-contaminated diets fed to their dams. Chemical analysis of the gilts' milk showed no effect of the diet on milk quality; DON was detected only in trace or &lt; 2 μg kg−1 concentrations. Necropsy data for the gilts, their pigs at weaning and at market weight showed no significant (P &gt; 0.05) differences among diets; however, evidence of linear (gilts) and quadratic (weaned and market pigs) trends were found for uterus weight. The feeding of diets containing up to 6.2 mg DON kg−1 (calculated to be 0.1 mg kg−1 body weight daily) to gilts during pregnancy and lactation did not appear to have any deleterious effects upon the gilts, or their progeny at weaning and at market weight. Key words: Deoxynivalenol, pregnancy, lactation, milk, gilts, pigs </jats:p

Impact of pure fumonisin B₁ on various metabolic parameters and carcass quality of growing-finishing swine — preliminary findings

Mycotoxin fumonisin B1 (FB1) is a common contaminant of corn and a causative agent of different animal and human diseases. An experiment was conducted to assess the impact of pure FB1 on carcass quality of growing-finishing swine. Pigs were fed diets containing 0, 0.11, 0.33 and 1.0 mg FB1 kg−1 (ppm) until market weight. Although performance characteristics were not different among the respective treatments, an increase in feed consumption variability was observed between weeks 3 and 9 for the 1 ppm FB1 fed pigs as compared with controls. The same animals showed an increased variability in carcass characteristics, in particular in the fat content of loin and ham. The estimated lean yield tended to decrease with increasing dose, but a high standard deviation abolished treatment differences. An elevated cholesterol value at the end of the experiment for the 1 ppm FB1 fed pigs suggested a disruption of lipid metabolism. No other significant (P &gt; 0.06) changes were observed. We conclude that a diet containing 1 ppm FB1 could have a detrimental effect on the carcass quality of a market pig and be a source of a monetary loss to the producer. Key words: Mycotoxin fumonisin B1, swine, carcass </jats:p