Study on effects of feeding laying hens on separate mycotoxins (aflatoxins, patulin, or citrinin)-contaminated diets on the egg quality and tissue constituents

A Study of Carry-Over and Histopathological Effects after Chronic Dietary Intake of Citrinin in Pigs, Broiler Chickens and Laying Hens

Citrinin (CIT) is a polyketide mycotoxin occurring in a variety of food and feedstuff, among which cereal grains are the most important contaminated source. Pigs and poultry are important livestock animals frequently exposed to mycotoxins, including CIT. Concerns are rising related to the toxic, and especially the potential nephrotoxic, properties of CIT. The purpose of this study was to clarify the histopathological effects on kidneys, liver, jejunum and duodenum of pigs, broiler chickens and laying hens receiving CIT contaminated feed. During 3 weeks, pigs (n = 16) were exposed to feed containing 1 mg CIT/kg feed or to control feed (n = 4), while 2 groups of broiler chickens and laying hens (n = 8 per group) received 0.1 mg CIT/kg feed (lower dose group) and 3 or 3.5 mg CIT/kg feed (higher dose group), respectively, or control feed (n = 4). CIT concentrations were quantified in plasma, kidneys, liver, muscle and eggs using a validated ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method. Kidneys, liver, duodenum and jejunum were evaluated histologically using light microscopy, while the kidneys were further examined using transmission electron microscopy (TEM). Histopathology did not reveal major abnormalities at the given contamination levels. However, a significant increase of swollen and degenerated mitochondria in renal cortical cells from all test groups were observed (p < 0.05). These observations could be related to oxidative stress, which is the major mechanism of CIT toxicity. Residues of CIT were detected in all collected tissues, except for muscle and egg white from layers in the lowest dose group, and egg white from layers in the highest dose group. CIT concentrations in plasma ranged between 0.1 (laying hens in lower dose group) and 20.8 ng/mL (pigs). In tissues, CIT concentrations ranged from 0.6 (muscle) to 20.3 µg/kg (liver) in pigs, while concentrations in chickens ranged from 0.1 (muscle) to 70.2 µg/kg (liver). Carry-over ratios from feed to edible tissues were between 0.1 and 2% in pigs, and between 0.1 and 6.9% in chickens, suggesting a low contribution of pig and poultry tissue-derived products towards the total dietary CIT intake for humans.

Development of a Sensitive Enzyme-Linked Immunosorbent Assay and Rapid Gold Nanoparticle Immunochromatographic Strip for Detecting Citrinin in Monascus Fermented Food

Antibodies against citrinin (CTN) were generated from rabbits, which were injected with CTN-keyhole limpet hemocyanin (KLH). This work involved the development of a sensitive competitive direct enzyme-linked immunosorbent assay (cdELISA) and a rapid gold nanoparticle immunochromatographic strip (immunostrip) method for analyzing CTN in Monascus-fermented food. CTN at a concentration of 5.0 ng/mL caused 50% inhibition (IC₅₀) of CTN-horseradish peroxidase (CTN-HRP) binding to the antibodies in the cdELISA. The capable on-site detection of CTN was accomplished by a rapid antibody-gold nanoparticle immunostrip with a detection limit of 20 ng/mL and that was completed within 15 min. A close inspection of 19 Monascus-fermented foods by cdELISA confirmed that 14 were contaminated with citrinin at levels from 28.6⁻9454 ng/g. Further analysis with the immunostrip is consistent with those results obtained using cdELISA. Both means are sensitive enough for the rapid examination of CTN in Monascus-fermented food products.

Hepato nephropathology associated with inclusion body hepatitis complicated with citrinin mycotoxicosis in a broiler farm

Aim:

Mortality in a broiler chicken farm was investigated for identifying the cause of mortality.

Materials and Methods:

A broiler farm with a population of 16000 succumbed to a disease outbreak. Clinical signs, vaccination history and mortality, were recorded. Necropsy examination and microscopic examination were carried out along with toxicological and molecular studies.

Results:

The clinical signs in the affected broiler birds were of non-specific nature with a total mortality of 26.39%. Postmortem examination and microscopical findings revealed hepatitis with basophilic intranuclear inclusion, splenitis, myocarditis, and nephritis. Glomerulonephritis was the prominent renal pathology recorded in this study. Polymerase chain reaction test confirmed the presence of fowl adenovirus (FAdV) genome in the target organs, and toxicological examination by thin-layer chromatography revealed the presence of a toxic level of citrinin in the feed samples.

Conclusion:

Based on various diagnostic investigations, the mortality in the flock was attributed to inclusion body hepatitis (IBH) complicated with citrinin mycotoxicosis. Thus, apart from liver pathology which occurs in a classical IBH cases, glomerulonephritis too occurs which are also a prominent finding which pathologists often miss. Thus, kidneys should also be examined histologically to assess the microscopic tissue alterations in poultry suspected for IBH along with a mycotoxicological analysis of feed. This will definitely throw light on the synergistic pathology elicited and exhibited by FAdV and mycotoxins in the poultry.

Mycotoxins and eggshell quality: cracking the problem

Good eggshell quality is essential for preservation of egg contents and embryonic life. Eggs with poor shell quality are rejected both as table eggs and as hatching eggs, leading to heavy economic losses. Dietary mycotoxins in laying hens can predispose them to or precipitate eggshell defects. Effects of various mycotoxins on poultry eggshell quality are reviewed. Methods in practice for alleviation of these effects have been discussed.

Effect of raising dietary protein, amino acids and/or energy levels as an attempt to alleviate severity of the chronic aflatoxicosis by broiler chicks. 2. Biochemical characteristics

Aflatoxin caused some reduction in moisture contents of chest and liver, lipids of thigh and blood, blood glucose, muscular protein and GOT in liver. It led also to increase of moisture contents of thigh and kidneys; chest lipids; blood cholesterol; protein of liver, kidneys and blood and blood creatinine. The different supplements used herein led to increasing moisture of muscles, liver and kidneys (except on oil addition); lipids of muscles (except of chest on high energy diet) and blood (except on amino acids-supplemented diet); blood cholesterol (except on high energy one); protein of thigh (except on high protein one) and blood (except on high energy or amino acids diets) and liver GPT (except on high energy diet). The additives led also to low blood glucose; protein of chest (except on high energy), liver, and kidneys; blood creatinine; liver GOT (particularly with high energy or amino acids); plasma GOT (on high amino acids) and plasma GPT. The 2-week withdrawal period led to low moisture contents of muscles and kidneys of most treatments, although they continued higher than in the control for chest, liver and kidneys. It increased blood glucose and cholesterol with continuous higher lipid content of muscles and blood and blood cholesterol than in the control. It led to elevated protein content of muscles, liver (except on the control or supplements mixture), kidneys (on the aflatoxin alone or with the amino acids) and blood (except on the control or aflatoxin alone or with high protein) and blood creatinine (except on the control or on the high energy or the supplements mixture).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of raising dietary protein, amino acids and/or energy levels as an attempt to alleviate severity of the chronic aflatoxicosis by broiler chicks. 1. Performance and toxicity symptoms

In an attempt to alleviate the aflatoxicosis symptoms by broiler chicks fed on low (50 ppb) aflatoxin-contaminated diet; the dietary nutrients were elevated by 2.6% for protein, 0.54 MJ ME/kg for energy or 0.5% for each of methionine and lysine. These supplements were mixed altogether and applied as well. All the experimental diets were offered for a 6-week period followed by a 2-week period on aflatoxin--free diet without supplements as a withdrawal period. It was proved after the treatment period that the raising of energy concentration was beneficial to overcome the aflatoxin effects on the body weight, feed conversion rate, and dressing (eviscerated weight) percentage and stability of relative weights of liver and kidneys. Additionally, the supplements' mixture improved the body weight and the relative weight of the liver comparing with the chicks fed on the aflatoxin diet without additives. All of the contaminated diets, except that of the high energy, caused apparently toxic symptoms besides the internal gross pathology. The high energy diet reflected the lowest mortality rate, whereas the highest was with the amino acids supplemented one. The withdrawal period resulted in lower differences among treatments in the body weight. It improved also the dressing percentage (significantly) and to some extent the results of the post-mortem examination.

Evaluation of the developmental toxicity of citrinin using Hydra attenuata and postimplantation rat whole embryo culture

Citrinin (a mycotoxin produced as a frequent contaminant of food and feed by numerous species of Aspergillus and Penicillium fungi) is embryo/fetotoxic and embryocidal in mice and rats. The present study was designed to examine whether the in vivo observed developmental toxicity of citrinin could be recapitulated using the Hydra attenuata (HA) bioassay and then be confirmed in rat whole embryo culture (WEC). Results from the HA assay indicated that the minimal affective concentrations of citrinin required to elicit a toxic response in the adult hydra (MACA) and in the regenerating hydra (MACD) were 30 mg/l and 20 mg/l, respectively. The Hydra developmental hazard index (A/D ratio) was equal to 1.5, classifying citrinin as a coaffective developmental toxin. In WEC, rat embryos were cultured in homologous (rat) serum containing citrinin at various concentrations ranging from 0.0 and 300 micrograms/ml for a period of 45 h. The results indicated a concentration-dependent reduction in yolk sac diameter, crown-rump length, somite number, protein and DNA contents. No embryonic dysmorphogenesis was observed in any treatment group. Histological examination revealed severe diffuse mesodermal and ectodermal necrosis in embryos treated with 250 micrograms/ml citrinin. At lower concentrations of citrinin, embryos were neither grossly nor histologically different from controls. Both the HA and WEC bioassays demonstrated that citrinin is not a primary developmental toxin. The use of HA and WEC bioassays in tandem may facilitate the rapid detection and ranking of the developmental hazards of food and feedborne mycotoxins.

Citrinin

Citrinin, a nephrotoxic mycotoxin, has been of growing importance also for the "International Agency for Research on Cancer", ever since its presumable role in the occurrence of Balcan endemic nephropathy (BEN) was discussed at the congress on "Mycotoxins, Endemic Nepthropathy and Urinary Tract Tumours" held in Lyon in June 1991 (12). In late 1991, citrinin was therefore also included in the list of toxins to be examined by the screening subcommittees on natural toxins of the International Live Science Institute, European Branch.