Micronucleus assay in bovine lymphocytes after exposure to bisphenol A in vitro.

Bisphenol A (BPA) [2,2-bis-(4-hydroxyphenyl) propane] is an important industrial agent, made by combining acetone and phenol, that is used extensively as a monomer in the production of polycarbonate plastics and as a precursor of epoxy resins. Micronucleus assays have served as an index of cytogenetic damage in in vivo and in vitro studies. We studied the genotoxic and cytotoxic effects of BPA on bovine peripheral lymphocytes in vitro. Lymphocyte cultures from two donors were exposed to four different concentrations of BPA (1 × 10(-4), 1 × 10(-5), 1 × 10(-6), and 1 × 10(-7) mol.L(-1)) for 48 h. The highest concentration of BPA (1 × 10(-4) mol.L(-1)) resulted in a significant increase in the number of micronuclei in comparison with the negative control (67.50 ± 2.121/1,000 binucleated cells versus 36.0 ± 5.657/1,000 binucleated cells in the DMSO control, P = 0.018). BPA did not affect the nuclear division index at any treatment concentrations. The present results thus demonstrate a significant genotoxic effect by BPA on bovine peripheral lymphocytes in vitro, only at the highest concentration.

Chromosomal aberrations in ovine lymphocytes exposed in vitro to tolylfluanid.

Chromosomal aberrations have been used as important cytogenetic biomarkers to study the mutagenic effects of different chemicals in vivo and in vitro. Chromosomal aberrations were evaluated in cultures of sheep lymphocytes in vitro exposed to the fungicide tolylfluanid. Lymphocyte cultures from three donors were exposed to four different concentrations of fungicide (1.10(-4) M(.)L; 1.10(-5) M(.)L; 1.10(-6) M(.)L; 1 × 10(-7) M(.)L). Chromosomal analysis showed a significant (P = 0.018 and 0.038 respectively, Anova test, P < 0.05, Tukey test) increase in the frequency of aberrant cells (ABC) in cultures treated with the highest negative experimental concentrations of tolylfluanid (1.10(-4) M(.)L; 1.10(-5) M(.)L) compared to control. Significantly increased numbers of chromatid breaks (7.67 ± 0.58% against 1.67 ± 2.08%, P = 0.009, Anova test, P < 0.05, Tukey test) and chromatid gaps (7.67 ± 1.15% against 2.67 ± 0.58%, P = 0.003, Anova test, P < 0.05, Tukey test) were observed in ovine cultures treated with the highest experimental concentration of tolylfluanid (1.10(-4) M(.)L). Tolylfluanid induced also chromosomal exchanges (P = 0.038, and 0.016 respectively, Anova test, P < 0.05, Tukey test) in ovine cultures treated with the highest experimental concentrations of tolylfluanid (1.10(-4) M(.)L; 1.10(-5) M(.)L). The mitotic index has not shown any statistical differences between the various treatments and control groups. Our results suggest a significant genotoxic effect of tolylfluanid only at the highest concentration in sheep peripheral lymphocytes in vitro.

Micronucleus frequency in sheep lymphocytes after in vitro exposure to fungicide tolylfluanid.

The fungicide tolylfluanid (N -dichlorofluoromethylthio-N', N -dimethyl -N -p -tolylsulfamide), was investigated by cytokinesis-block micronucleus assay. Tolylfluanid at the lowest concentration (1 x 10(- 6)mol L(- 1))did not influence significantly the frequency of micronuclei in sheep lymphocyte cultures in comparison with control (32.33 +/- 3.51/1000 binucleated cells versus 30.33 +/- 2.82/1000 binucleated cells in dimethylsulfoxide (DMSO) control, P = 0.44). Higher tolylfluanid concentrations (1 x 10(- 4) and, 1 x 10(- 5) mol L(- 1)) resulted in a significant dose-dependent increase in the number of micronuclei in comparison with control (74.00 +/- 13.00/1000 binucleated cells and 52.67 +/- 10.12/1000 binucleated cells versus 30.33 +/- 2. 82/1000 binucleated cells in DMSO control, P = 0.005 and 0.02, respectively, ANOVA followed by Tukey test P < 0.05). Many of the treated cells also possessed multiple micronuclei. Tolylfluanid did not affect the nuclear division index at all treatment concentrations. Our in vitro results thus demonstrate that tolylfluanid had a significant genotoxic effect at only the highest concentration tested.

Some food toxic for pets.

According to world statistics, dogs and cats are the species that owners most frequently seek assistance with potential poisonings, accounting 95-98% of all reported animal cases. Exposures occur more commonly in the summer and in December that is associated with the holiday season. The majority (>90%) of animal poisonings are accidental and acute in nature and occur near or at the animal owner's home. Feeding human foodstuff to pets may also prove dangerous for their health.The aim of this review was to present common food items that should not be fed (intentionally or unintentionally) to dogs, i.e. chocolate, caffeine, and other methylxanthines, grapes, raisins, onion, garlic, avocado, alcohol, nuts, xylitol contained in chewing gum and candies, etc. Onion and avocado are toxic for cats, too. The clinical effects of individual toxicants and possible therapy are also mentioned. Knowing what human food has the potential to be involved in serious toxicoses should allow veterinarians to better educate their clients on means of preventing pet poisonings.It can be concluded that the best advice must surely be to give animal fodder or treats specifically developed for their diets.

Chromosomal aberrations and frequency of micronuclei in sheep subchronically exposed to the fungicide Euparen Multi (tolylfluanid).

We analyzed chromosome aberrations, micronucleus frequency, mitotic index (MI), and nuclear division index (NDI) in peripheral lymphocytes of sheep subchronically exposed to the fungicide Euparen Multi (containing 50% tolylfluanid). Euparen Multi was administered by rumen sonde to group of Merino sheep (seven sheep/group) at 93 mg/kg body weight (1/20 LD50) daily for 28 days to assess its genotoxic effects. The frequencies of aberrant cells (ABC) in the experimental and control groups were 5.50+/-1.38% and 2.40+/-1.14%, respectively, and the increase in ABC in the treated group was significant (P = 0.003). Significantly increased numbers of chromatid breaks (5.67+/-1.21% against 2.40+/-1.14%; P = 0.001), chromatid gaps (10.33+/-2.73% against 4.00+/-1.23%; P = 0.001), and chromosome gaps (1.83+/-0.75% against 0.80+/-0.45%; P = 0.025) and exchanges (3.17+/-1.94% against 0.20+/-0.45%; P = 0.009) were observed in exposed animals in comparison to control animals. The frequency of micronuclei (MN) was 29.40+/-5.86 per 1000 binucleated cells in peripheral lymphocytes of sheep in the control group and 49.57+/-19.12 per 1000 binucleated cells in the treated group. A significant increase in the frequency of MN in peripheral lymphocytes also was observed between the two groups (P = 0.0477). No statistical differences in MI and NDI values were found in the groups (P = 0.181 and 0.761, respectively). Thus, our results suggest that exposure to Euparen Multi may cause genome damage in somatic cells.

Chromosome damage in peripheral lymphocytes of sheep induced by chlorine in drinking water.

The potential of chromosomal damage associated with the effects of chlorine in drinking water was evaluated using chromosome aberrations and micronuclei as cytogenetic endpoints in the lymphocytes of peripheral blood of ewe lambs. The study assessed the in vivo effects of high chlorine doses (1.8 mg l(-1), based on Savo-Super disinfectant) in drinking water on the peripheral lymphocytes of sheep after 30 days. The frequency of aberrant cells (AB.C.) in the experimental and control groups was 31.80+/-13.68% AB.C. and 4.50+/-2.07% AB.C. respectively, and the increased AB.C. in the treated group was highly significant (P=/<0.001). In the experimental group chromatid breaks (26.20+/-10.47%) and gaps (24.20+/-13.94%) were the dominant types of aberrations, but statistically significant chromosome gaps and exchanges were also present. The frequency of micronuclei in peripheral lymphocytes of sheep in the control group was 21.17+/-4.36 per 1,000 binucleated cells and 64.20+/-22.51 per 1,000 binucleated cells in the experimental group. A significant increase in the frequency of micronuclei in peripheral lymphocytes of sheep was observed between the two groups (P=0.001).

A possible relationship between viral infection and chromosome damage in breeding boars.

A cytogenetic analysis of peripheral blood lymphocytes was carried out on breeding boars (n = 5) on a farm where viral infections (porcine parvovirosis) had occurred. Several different types of chromosomal aberrations were observed including chromatid breaks (23.60 +/- 2.88%), exchanges (9.60 +/- 8.99%), and fragments (4.26 +/- 3.31%). In addition, 2.94 +/- 1.74% of cells in metaphase showed pulverization. Cells with multiple aberrations were seen in two of five boars. The chromosomal damage in the boars may have been induced by a genotoxic agent such as a viral infection, and may also be related to the reproductive impairment of the pigs.