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The epoxiconazole was tested in vitro for its potential on induction of chromosome damage and/or cell cycle kinetics in cultured bovine peripheral lymphocytes. Cytogenetic endpoints such as: Chromosome Aberrations (CA); Sister Chromatid Exchanges (SCE); Micronuclei (MN); Mitotic Index (MI); Proliferation Index (PI); and Cytokinesis Block Proliferation Index (CBPI) were investigated for 24 h and 48 h of incubation. The cultured lymphocytes were exposed to the epoxiconazole at concentrations of 2.5, 5, 10, 25, 50 and 100 μg mL−1. From our results is evident that treatment of bovine peripheral lymphocytes with the epoxiconazole was not related to DNA damage; no genotoxic effect and/or clastogenic/aneugenic effects were recorded. However, epoxiconazole has ability to significantly affect cell cycle kinetics/and induce apoptosis. A decrease of proliferation in the MI, CBPI and identically in the PI were observed; hence, cytostatic/cytotoxic effects of epoxiconazole have been recorded. The prolonged time of exposure at the highest concentration caused an inhibition of the replication. Electrophoretic analysis confirmed the epoxiconazole potential to induce ladder-like patterns of DNA fragments that are a hallmark of apoptosis.

Tango® Super is a two-compound fungicide formulation widely employed in grain protection. However, details of Tango® Super effects on cell cultures have not been fully investigated. In this study, bovine lymphocytes were exposed to a concentration range 0.5; 1.5; 3; 6; and 15 μg mL−1 for 4 h to assess the cytotoxicity and genotoxicity of the fungicide. Our experiments revealed that this fungicide treatment reduced cell viability, decreased cell proliferation and provoked apoptotic cell death. Cell cycle analysis showed predominant accumulation of cells in the G0/G1 phase of the cell cycle. The fungicide was able to induce mitochondrial superoxide production accompanied by elevated levels of carbonylated proteins and changes in the lipid membrane composition. The fungicide did not induce micronuclei production, but stimulated both DNA double-strand breaks and the formation of p53 binding protein, which is accumulated during the DNA repair process at the site of double-strand breaks. Based on the obtained data we suppose that the fungicide-induced DNA damage is the result of oxidative stress, which may contribute to higher occurrence of apoptotic cell death. Because ergosterol biosynthesis-inhibiting fungicides are widely used in agriculture to ensure higher crop yields and may cause health impairment of animals and humans, there is a need for further testing to elucidate their potential genotoxic effects using in vivo and/or in vitro systems.

Potential genotoxic/cytotoxic effects of the epoxiconazole/fenpropimorph-based fungicide were investigated using single cell gel electrophoresis and cytogenetic assays: chromosomal aberrations, sister chromatid exchanges, micronuclei and fluorescence in situ hybridization in cultured bovine lymphocytes. No statistically significant elevations of DNA damage and increases in cytogenetic endpoints were seen. However, evident cytotoxic effect presented as a decrease in mitotic and proliferation indices were recorded after exposure of bovine lymphocytes to the fungicide for 24 and 48 h at concentrations ranging from 3 to 15 µg mL(-1) (P < 0.05, P < 0.01, P < 0.001). Similarly, for 24 h an inhibition in the cytokinesis block proliferation index (CBPI) was obtained after exposure to the fungicide at concentrations ranging from 1.5 to 15 µg mL(-1) (P < 0.01, P < 0.001) in each donor.

In this study, chromosomal imbalances in tumor tissues (lymphomas) and nucleotide changes in tumor suppressor TP53 were studied in a Bernese Mountain dog bitch and a cross breed bitch. Using comparative genomic hybridization, numerous chromosomal rearrangements were detected, which indicated the heterogeneity in tumor growth: in the cross breed bitch, a deletion on the chromosome 9, and duplications on chromosomes 5, 8 and 17 have been found. In the Bernese Mountain Dog bitch, losses on chromosomes 1, 5, 8, 12, 18, 22, 27, 29 and gains on chromosomes 1, 2, 9, 11, 15, 16, 18, 20, 23, 24, 25, 28, 29, 30, 34, 36, 37 and 38 were identified. With the sequencing of the TP53 gene, one silent mutation, transition A/G at position 138 in exon 5 was detected, without changing the amino acid.

An 8-month-old female Staffordshire bull terrier was clinically examined because of external sexual organs abnormality-clitoral hypertrophy. As stated by the owner, the female dog had not been in heat yet. Serum profile of testosterone (3.39 ng/ml), as well as an anti-Műllerian hormone (24.0 ng/ml), suggested the presence of testicular tissue. On the contrary, the estimated level of 17β-oestradiol (24.6 pg/ml) was approximately two times higher when compared with the normal anoestrus values (5-10 pg/ml). A midline laparotomy was performed to detect the cranial parts of the genital system. Gonads resembling testicle or ovotestis (left) and hypoplastic testicle (right) was visible. Cranial portion of gonads was attached to structures indicative of bilateral epididymidis. The next tubular structures-oviducts were resected along with adherent parts of a hypoplastic uterus. Histological evaluation confirmed that the examined gonad samples were testicles with modified interstitial testicular tissue. Hypertrophy of interstitial space was predominantly formed by Leydig cells. Examination of a cross-section through the head of suspected epididymidis confirmed their characteristic structures. In addition, the characteristic configuration of the oviducts was presented. The uterus consisted of three walls, in which the endometrium was hypoplastic with the presence of endometrial glands. No Y chromosome was detected by chromosomal analysis using CFA Y probe and the amplification of SRY-gene coding region (813 bp) indicated genotype 78, XX; SRY-negative. Sequencing of SOX9 gene exons 1-3 did not reveal any differences in exon 1 and 3. On the contrary, a few changes were determined in the SOX9 exon 2 sequences: G instead of A at position 103; C instead of reference T at position 115; GCG instead of reference CGC at position 138-140; T instead of reference C at positions 161, 164 and 167.

The aim of the present study was to investigate the effect of triazole fungicide Prosaro® (tebuconazole/prothioconazole) on the induction of micronuclei (MNs) and DNA damage in bovine peripheral lymphocytes. Whole blood cultures or isolated lymphocytes were exposed to 1.5, 3, 7.5, 15 and 30 μg ml−1 concentrations of triazole formulation for 24 and 48 h, or 2 h for MN and Comet assays. For 24 and 48 h of incubation with the fungicide no significant elevations in the MN frequencies in bovine lymphocytes were found. However, a clear reduction of cytochalasin-blocked proliferation index (CBPI) was observed in the donors (p < 0.05, p < 0.01, and p < 0.001). After the prolonged time of exposure the highest concentrations resulted in nearly total inhibition of cell proliferation (30 μg ml−1). After the use of Comet assay, only a moderate increase in DNA damage without statistical significance was recorded, except the highest concentration (30 μg ml−1; p < 0.05).

Three different pesticide formulations were tested for micronuclei production and cell cycle arrest. Micronucleus test represents a suitable method for assessing chromosome damage because both chromosome breakage (clastogenicity) and chromosome loss (aneugenicity) can be measured simultaneously. In the experiments for 24 and/or 48 h exposure, no significant increase (p < 0.05) in MN frequency was found in comparison with negative control. On the contrary, the values of CBPI (cytochalasin blocked proliferative index) were significantly reduced in a dose dependent manner (p < 0.05, p < 0.01, p < 0.001) for both exposure time. Our results indicated an expressive cytotoxic effect of various pesticides in cultivated bovine peripheral lymphocytes.

Proceeding deals with of genomic changes detectable by FISH . The DSD syndrom in Yorkshire terrier 78,XY t (Y-;6p+) was observed by the use of X and Y FISH WCP probes. Following results indicated numerous genomic changes in cancers. Using comparative genomic hybridization numerous chromosomal rearrangements were detected, which indicated the heterogeneity in tumour growth. In Bernese Mountain Dog bitch,8 loses on chromosomes and gains on 18 different of chromosomes were detected. The last study was focused on chromosomal position and nucleotide sequencing of the LCA5L exons. Those were analysed in cattle of BTA1q44, sheep OAR1q43 and of CHI1q44 in the goats. Keywords: fluorescent in situ hybridization, FISH, veterinary diagnostics References ALARM, M. R. et al. (2007) Male pseudohermafroditism in dogs: three case reports. Veterinarni Medicina 52 pp.74- 78. Hallermann, C . et al. (2004) Chromosomal Aberration Patterns Differ in Subtypes of Primary Cutaneous B Cell Lymphomas. J. Invest. Dermatol. 122 pp. 1495–1502. D’Haese, J . G. et al .(2005) Chromosomal aberrations in follicular non-Hodgkin lymphomas of Japanese patients, detected with comparative genomic hybridization and polymerase chain reaction analysis. Cancer Genet. Cytogenet. 162 pp. 107–114. Di MEO, G.P. et al. ( 2006) Mapping of 11 genes by FISH to BTA2, BBU2q, OAR2q and CHI2, and comparison with HSA2q. Anim. Genet. 2006; 37 pp. 299-300. NAFSTRoM K . et al .(2007). Effective treatment for the canine RPE65null mutation, a hereditary retinal dystrophy comparable to human Leber’s congenital amaurosis. In: Retinal degenerations: biology, diagnostics, and therapeutics. 1st edn. Humana Press Inc., Totowa, New Jersey, pp. 415-431. Schibler L . et al. (2009) Molecular cytogenetics and comparative mapping in goats (Capra hircus, 2n=60). Cytogenet. Genome Res .126 pp 77-85. Streubel, B . et al. (2003) T(14;18)(q32;q21) involving IGH andMALT1 is a frequent chromosomal aberration in MALT lymphoma. Blood 101 pp . 2335–2339 .

Lymphoma is the most frequent hematopoietic neoplasm in dog, and it shares some clinical, cytological, histopathological and molecular similarities with humans. In our study, DNA changes in TP53 , c-KIT and N-RAS were detected in lymphoma tissues of cross breed bitch and Bernese Mountain Dog bitch. One transversion A/G at nucleotide position 138 in exon 5 in TP53 gene and one transversion A/G at nucleotide position 35 in exon 8 of c-KIT gene were observed in donor 2. It seems that these genes did not play a key role in canine lymphoma formation and progression.

Possible genotoxic effect of thiacloprid on bovine cultures of whole blood was investigated using chromosomal aberrations (CAs), micronuclei (MN), sister chromatid exchanges (SCEs), DNA damage and apoptotic DNA fragmentation assays. The cells of whole blood were exposed to thiacloprid (30, 60, 120, 240 and 480 μg mL−1) for the last 24 and 48 h of cultivation. Thiacloprid did not induce significant increase in CAs after 24 and 48 h; only the concentration of 120 μg mL−1 caused elevation of CAs (p

To date, most data about the possible genotoxic effect of triazole pesticides are focused on laboratory animals resulting in limited information on further non-target organisms such as cattle. The objective of the present study was to investigate the effect of triazole (tebuconazole/prothioconazole) fungicide formulation on the induction of chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and DNA fragmentation in bovine cultured lymphocytes. Our results showed that the fungicide formulation did not induce significant number of CAs in bovine cells after 24 h treatment. Nevertheless, the dose-dependent reduction of mitotic division was observed, with the strongest effect at 30.0 μg mL(-1) in both donors (P0.01 and P0.001, respectively). Prolonged 48 h exposure caused the increased level of breaks in treated cultures (3.0-15.0 μg mL(-1); P0.05) and significant decrease in mitotic index (MI). The tested fungicide failed to produce any statistical changes in the SCE frequency neither after 24 h nor 48 h treatment. However, the significant decline of the proliferation index (PI) was observed after 24 h indicating the fungicide influence on cell cycle kinetics. Prolonged 48 h exposure caused cytotoxicity reflecting in lower PI value relative to control mainly at the highest fungicide concentrations (30.0 μg mL(-1), P0.001). Using painting probes for bovine chromosomes 1, 5 and 7 (BTA1, BTA5 and BTA7) only low levels of aneuploidies were detected. Significant increase of polyploidy cells (P0.05) was induced by a 3.0 μg mL(-1) dose of the fungicide after 48 h. DNA fragmentation assay didn't reveal the presence of DNA nucleosome ladder in cell cultures at any time (24 h and 48 h) and fungicide concentration.

The changes in cattle acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities after exposure to tebuconazole-based fungicides (Orius and Prosaro®) in vitro were determined spectrophotometrically according to the Ellman method. The fungicides induced the decrease in AChE and BChE levels in a dose-dependent manner. Statistically significant inhibition of erythrocyte AChE levels was observed in the concentration range from 150 to 300 μg ml−1 (p < 0.001) for Orius and from 100 to 300 μg ml−1 for Prosaro® (p < 0.01 and p < 0.001, respectively). Levels of BChE activity were more reduced for the fungicide Orius (40–50%) than for Prosaro®. Statistical significance in the inhibition of BChE activity was found after exposure of cattle plasma to both fungicides at concentrations starting from 150 μg ml−1 (p < 0.001). Our results indicate that tebuconazole-based fungicides are able to reduce cattle AChE and BChE activities.

Tango

The potential genotoxic effect of thiacloprid formulation on bovine peripheral lymphocytes was evaluated using the comet assay and the cytogenetic endpoints: chromosome aberrations (CAs), sister chromatid exchanges (SCEs) and micronuclei (MNi). Whole blood cultures were treated with the insecticide at concentrations of 30, 60, 120, 240 and 480 μg mL(-1) for 24, 48 h and/or 2 h of incubation. A statistically significant increase in the frequency of DNA damage, as well as in unstable chromosome aberrations (% breaks) were found after exposure to the insecticide at concentrations ranging from 120 to 480 μg mL(-1) (P < 0.05, P < 0.01, P < 0.001). For the detection of stable structural chromosome aberrations (e.g., translocations) and numerical aberrations by the FISH method, three whole chromosome painting probes for bovine chromosomes 1, 5 and 7 (BTA1, BTA5 and BTA7) were used in our experiments. We observed numerical aberrations, but without any statistical significance. Regarding the sister chromatid exchanges, no significant elevation in the SCE frequencies was found after 24-h exposure to the insecticide. A dose-related response in the SCE induction was obtained in bovine cultures after the prolonged time of exposure (48 h) to thiacloprid formulation at concentrations ranging from 120 to 480 μg mL(-1) in each donor (P < 0.05, P < 0.01), which was associated with a reduction of the PI (P < 0.05, P < 0.01). The insecticide failed to produce MNi; however, a significant reduction of CBPI was observed. Using real-time PCR, a decrease in the expression of bovine glutathione S-transferase M3 (GSTM3) was detected at the lowest dose. The higher concentrations of thiacloprid formulation caused an increase in the mRNA expression.

The protective effect of Vitamin E and selenium was studied for the possibility of decreasing the chromosome aberrations (CA), micronuclei (MN) and sister chromatid exchanges (SCE) induced by carbon tetrachloride (CCl(4)) in ovine peripheral lymphocytes cultured in vitro. The cultures of lymphocytes from two healthy lambs were treated with carbon tetrachloride at concentrations of 2, 4, 8, and 16 microg/ml for the last 48 h of cultivation and subsequently with the same doses of CCl(4) and Vitamin E and selenium. A possible metabolic modification in carbon tetrachloride genotoxicity was detected with the application of S9 fraction for 2h. No positive clastogenic effect of CCl(4), and subsequently no protective effect of either antioxidant was obtained in the CA assay. In the MN assay for 48 h, an increase and, respectively, a decrease in the frequency of MN was found in cultures treated with CCl(4) alone and in cultures treated concurrently with CCl(4), Vitamin E and selenium at concentrations of 8 and 16 microg/ml (P0.001 and P0.01). High statistical significance was achieved in SCE assay after the treatment of ovine peripheral lymphocytes with CCl(4) at all concentrations tested (P0.001), except the lowest dose. A significant decrease in SCEs was obtained in cultures treated simultaneously with CCl(4), Vitamin E and selenium (P0.001). The highest dose (16 microg/ml) was also shown to improve the cell-cycle kinetics in comparison with corresponding unprotected dose (P0.01). Insufficient confirmation of the genotoxicity of CCl(4) and the protective effect of the antioxidants, respectively were seen in cultures with metabolic activation.

The effect of in vivo feeding of metal-containing emissions from an aluminum refining plant upon the induction of sister-chromatid exchanges (SCEs) and mitotic delay was investigated in cultured sheep lymphocytes. The experimental animals were given a daily dose of industrial emissions (mostly aluminum and fluoride) of either 0.75 g or 1.5 g/animal, for 1 year. The experiments were aimed at induction of chronic fluorosis under clinical conditions. A significant increase in mean serum fluoride, aluminum, arsenic and cadmium levels between both experimental groups and control was observed from 5 and 7 months on, respectively. The occurrence of SCEs in the experimental groups was higher (reaching statistical significance at a dose of 1.5 g/animal) than that seen in the controls. The emission was found to reduce the proliferation index. A significant heterogeneity of the first, second and third metaphases as compared to the controls was also observed.

A 9-month-old Yorkshire terrier was admitted to the clinic because of abnormal sexual behaviour and clitoral hypertrophy. External examination confirmed standard development of caudal genital organs: vagina, vulva and cervix uteri. Serum profile of gonadotropin hormones 17 β-estradiol (10.0 pg.ml(-1)) and testosterone (9.1 ng.ml(-1)) revealed the presence of testicular tissue. A midline laparotomy was performed to detect the cranial parts of the genital system. Gonads resembling testicles, structures indicating epididymis and rudimentary deferent ducts were resected, along with adherent part of the uterus. Cytogenetic analysis showed a male chromosomal complement 78, XY in all metaphases of the studied Yorkshire terrier dog. The chromosomal constitution was confirmed by fluorescence in situ hybridisation (FISH) with whole-chromosome painting probes specific for chromosomes X and Y, as well as by polymerase chain reaction (PCR) amplification of the 271-bp Y-linked fragment of SRY (the sex-determining region on the Y chromosome) gene. Sequencing of the dog's SRY gene coding region did not reveal any mutation. To search for potential mutation in the SOX9 gene (Sry-box containing gene 9), which is considered to be one of the key genes involved in the sex determination process, the PCR fragments of exons 1, 2 and 3 originating from the canine patient were sequenced in order to compare with both male and female healthy control dogs. In the analysed regions of the SOX9 gene, no mutation was found.

The tebuconazole-based fungicide was tested in vitro for its potential genotoxic and cytotoxic effects on cultured bovine peripheral lymphocytes. Following 24 h and 48 h of incubation, several cytogenetic endpoints were investigated such as: Chromosome Aberrations (CAs); Sister Chromatid Exchanges (SCEs); Micronuclei (MN); Mitotic Index (MI); Proliferation Index (PI); and Cytokinesis Block Proliferation Index (CBPI). The cultured lymphocytes were exposed to the fungicide formulation at concentrations of 3, 6, 15, 30 and 60 μg mL−1. Statistical significant increases were seen in the CA assays at concentrations ranging from 6 to 30 μg mL−1 for 24 h. The higher doses caused a decrease or total inhibition of chromosome damages in comparison to the last active dose, or the control values. The Fluorescence in situ Hybridisation (FISH) technique was also used for the study of stable/unstable structural chromosomal aberrations and numerical aberrations of aneuploidy/polyploidy at the concentrations of 6 and 15 μg mL−1. Under conditions of our study, no reciprocal translocations were detected. The more frequent types of aberrations were trisomies and monosomies; both have been identified in association with either bovine chromosome 5 or 7. No statistical significant value was seen in the induced MN; but, the clear, evident reduction of the CBPI was observed. Significant elevations of SCE were observed after the applications of the fungicide formulation at doses from 15 to 60 μg mL−1 in each donor for 24 h. The highest concentrations also caused a statistical significant decrease in the PI. The treatment for 48 h failed to exhibit any genotoxic activity of the fungicide.

We investigated the effect of NDMA and DNSGU on the induction of chromosomal aberrations and sister-chromatid exchanges (SCEs), as well as the influence of the former compound on cell-cycle kinetics in cultured cow peripheral lymphocytes. A clastogenic effect was observed in treated cell cultures at 6 or 12 × 10 −5 M concentrations of NDMA and DNSGU, respectively, but no increase of chromosomal breaks was seen at the lowest dose. NDMA at 6 × 10 −4 M was toxic to cow lymphocytes. NDMA and DNSGU induced statistical increases of SCEs at the test doses (6 or 12 × 10 −6 and 6 or 12 × 10 −5 M, respectively). In addition, treatment with NDMA at a dose of 6 × 10 −5 M revealed significant heterogeneity of the first, second and third metaphases between treated and untreated groups. A reduction of the proliferation index and proliferation delay per cycle was shown too.

The effect of the fungicide Euparen Multi (containing 50% tolylfluanid) was investigated on the induction of chromosomal aberrations (CA) in cultured bovine peripheral lymphocytes. Cultures from two healthy donors were treated with tolylfluanid-based fungicide at concentrations ranging from 1.7 to 17.5 μg/ml for the last 24 and 48 hours of cultivation. Conventional cytogenetic method (CA assay) with Giemsa staining as well as fluorescence in situ hybridization (FISH) with whole bovine chromosomes 1 and 5 painting probes were used in the experiment. In the CA assay, no clastogenic effect of the fungicide was found after Euparen Multi treatment for 24 hours. On the contrary, significant elevation in polyploidy induction was observed with dose-dependence in one of the donors. Using prolonged time of exposure to the fungicide (the last 48 h of the cultivation), a slight clastogenic effect was detected at the doses of 8.75 and 17.5 μg/ml (P < 0.05, P < 0.01, respectively) in donor 1 and at the dose of 8.75 μg/ml (P < 0.05) in donor 2. The highest doses tested caused reduction of the mitotic indices (MI) (P < 0.05, P < 0.01) in both donors as well as both treatment times. The evaluation of stable structural aberrations in lymphocytes by two-colour FISH (48 h exposure) using bovine chromosome painting probes revealed the presence of nonreciprocal translocations at two examined concentrations (3.5 μg/ml and 8.75 μg/ml).

The potential for genotoxic and cytotoxic effects of tolylfluanid-based fungicide (50% active agent) was evaluated using sister chromatid exchange (SCE) and proliferation indices (PI) in cultured bovine peripheral lymphocytes. For the detection of possible genetic damage, DNA fragmentation assay was also applied. Bovine lymphocytes cultured for 72 h were treated with the fungicide at the final concentrations of 1.75, 3.5, 8.75, and 17.5 µg/mL for the last 24 and 48 h of culture without S9 metabolic activation, and during the last 2 h of culture with S9 metabolic activation. In the SCE assays no evidence for genotoxic activity of the fungicide was found in treatments of 24 h without and 2 h with S9. After the 24 h exposure to tolylfluanid, a weak decrease in the PI was observed. With the prolonged exposure time (48 h), dose dependence in the increase of SCE frequencies was observed. Moreover, after 48 h exposure slight fragmentation of DNA at the concentrations of 3.5 and 8.75 µg/mL was demonstrated. SCE quantification is the most widely used approach for the assessment of genotoxic/cytogenetic effects of chemical compounds. Positive results in the assay at 48 h exposure indicated a potential of the fungicide to increase frequency of chromosomal damage (replication injuries) that is the confirmation of early effect of exposure.

Bendiocarb is a carbamate broad-spectrum insecticide used to control disease vectors such as mosquitoes and flies, as well as household and agricultural pests. Nowadays, only few papers reporting cytogenetic or possible genotoxic effect of this insecticide on mammalian cells are available. In the present study 24-hour exposure to bendiocarbamate at concentrations ranging from 20 to 160 µg/ml was used for investigation of unstable chromosomal aberrations (CA), sister chromatid exchanges (SCE) and stable chromosomal aberration induction in cultured bovine peripheral lymphocytes. The slight but no significant increase of chromatide breaks frequency was observed after the exposure of lymphocytes to 80 µg/ml of bendiocarb. At the highest concentration added to the cell cultures (160 µg/ml) mitotic index decrease was shown in both donors (p < 0.05; p < 0.01). Both statistically significant elevation of SCEs (p < 0.05) and a reduction of proliferative indices (PI) (p < 0.01) were shown at a dose of 80 µg/ml. By means of two fluorescent-labelled whole chromosome-painting probes, stable aberrations such as bovine chromosome 1 and 5 translocation as well as numerical aberrations (polyploidies, heteroploidies) were visualised under fluorescent microscope in some examined metaphases.

The effects of low doses of cyclohexanol exposure were studied in mouse bone marrow cells including chromosome aberrations (CA), micronucleus (MN) and sister chromatid exchanges (SCE) as biomarkers. Capillaries with a tested agent that was evaporated continuously were placed in an experimental chamber for six weeks. No clastogenic and/or aneugenic effect of CA and MN induction was observed. A significant elevation of induced damage was achieved in the SCE study (p < 0.001) that has confirmed the early exposure of cyclohexanol to mice.

A technical herbicide containing isopropyl amine salt of glyphosate was tested for induction of chromosome aberrations (CA) and sister chromatid exchanges (SCE) in cultured bovine peripheral lymphocytes. Cultures were exposed to a glyphosate formulation at concentrations ranging from 28 to 1120 micromol/l without and with metabolic activation. No clastogenic effect of the herbicide was found. Its genotoxic effect was confirmed in the SCE assay after 24 h of incubation. A statistically significant elevation in SCE induction was observed in each of the donors after application of the product at doses ranging from 56 to 1120 micromol/l. The highest concentrations (560 and 1120 micromol/l) also caused reduction of mitotic and proliferation indices. In the 2 h-assay with metabolic activation a statistically significant frequency of SCE was observed only in cultures treated with the agent at a concentration of 140 micromol/l.

The commercial herbicide with active element bifenox (principal tradename Modown) was tested for the evaluation of genotoxicity in cultured cow peripheral lymphocytes in vitro. Several cytogenetic endpoints as chromosome aberrations (CA), sister chromatid exchanges (SCE), mitotic (MI) and proliferation (PI) indices were investigated in different sampling times. To detect possible metabolic modifications in herbicide genotoxicity, the cultures for SCE determination were also treated with S9 fraction. Cultures of lymphocytes were exposed to the herbicide at concentrations of 25, 50, 250, 500 and 1000 microg/ml. A slight increase of CAs was found after exposure of this agent to doses ranging from 25 to 250 microg/ml for 24 h. In the CA assay no statistical significance was seen. Both higher doses (500 and 1000 microg/ml) caused a decrease of chromosome damage in comparison to the last active dose or control values correlated to induced cytotoxicity. Four concentrations (all except the highest one) of the herbicide were applied into cultures in SCE assays both with and without metabolic activation. Significant elevations of SCE were observed after applications of herbicide tested at doses of 250 and 500 microg/ml in each donor (P