Chlormequat chloride promotes rat embryonic growth and GH-IGF-1 axis.

Chlormequat chloride, a plant growth regulator, is widely applied in agriculture because it can promote sturdier growth of the crops. In this research, we found that rat embryo growth on GD11 was inhibited in vitro at 50 µg/ml but promoted in vivo at 75 mg/kg.bw by maternal oral exposure. Therefore, the concentrations of chlormequat chloride in the sera of the pregnant rats on gestation day (GD)11 were determined by a high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) test to be 1.94 ± 0.023 µg/ml, 3.84 ± 0.080 µg/ml, and 7.08 ± 0.11 µg/ml, respectively, when the pregnant rats were orally exposed to chlormequat chloride at 75, 137.5, and 200 mg/kg.bw. Hence, we performed WEC tests again and confirmed that the rat embryo growth in vitro was promoted by chlormequat chloride at 5 µg/mL. The embryonic growth hormone (GH) and insulin-like growth factor 1 (IGF-1) levels were increased by chlormequat chloride both in vitro and in vivo compared with the control ones. We concluded that chlormequat chloride could elevate GH and IGF-1 levels in embryos and promote embryonic growth both in vitro and in vivo.

Effect of chlormequat (cycocel) on the growth of ornamental cabbage and kale (Brassica oleracea) cultivars 'Kamome White' and 'Nagoya Red'.

The effect of concentration and application method of chlormequat (cycocel), a plant growth retardant, on plant height and some other traits in Brassica oleracea cultivars 'Kamome White' and 'Nagoya Red' was assessed. Plant growth retardants are commonly applied to limit stem elongation and produce a more compact plant. The experiment was done as a factorial in randomized completely blocks design (RCBD) with four replications. Plants (40 days after transplanting) were sprayed and drenched with 500, 1000 and 1500 mg l(-1) cycocel. In each experiment, control untreated plants. Data were recorded the 60 and 90 days after transplanting. Based on analysis of variance (ANOVA), the effect of different treatments and their interaction on all traits was significant at 0.05 or 0.01 level of probability. Treatment of 1500 mg I(-1) cycocel resulted in about 50 and 20% shorter plants than control plants, 60 and 90 days after transplant. The growth of Brassica oleracea cultivar 'Kamome White' and 'Nagoya Red' decreased with increased cycocel concentration. Foliar sprays of cycocel controlled plant height of both cultivars. Results indicated that the shortest plants (9.94 and 11.59 cm) were those sprayed with 1500 mg l(-1) cycocel in cultivar 'Kamome White' after 60 and 90 days, respectively. The largest number of leaves (33.94) and highest leaf diameter (9.39 cm) occurred in cv. 'Nagoya Red', when drench was used. Maximum dry matter (14.31%) accumulated in cv. 'Nagoya Red', treated with spray.

Comparisons of metabolic and physiological changes in rats following short term oral dosing with pesticides commonly found in food.

¹H Nuclear Magnetic Resonance spectroscopy has been used to profile urinary metabolites in male Fischer F344 rats in order to assess the metabolic changes induced by oral exposure to two benzimidazole fungicides (carbendazim and thiabendazole) and two bipyridyllium herbicides (chlormequat and mepiquat). Exposure levels were selected to be lower than those expected to cause overt signs of toxicity. We then compared the sensitivity of the metabolomics approach to more traditional methods of toxicity assessment such as the measurement of growth and organ weights. Separate, acute exposure experiments were conducted for each pesticide to identify potential metabolic markers of exposure across four doses (and a control). Growth, organ weights and feeding/drinking rates were not significantly affected by any compounds at any dose levels tested. In contrast, metabolic responses were detected within 8 and 24h for chlormequat and mepiquat, and after 24h for carbendazim and thiabendazole. These results demonstrate the potential for the use of metabolomics in food toxicity testing.

Occurrence and risks associated with chlormequat residues in a range of foodstuffs in the UK.

Trends in the usage pattern of chlormequat (a plant growth regulator) on cereal crops in the UK over the past 6 years are presented. The figures have been supplemented by monitoring of chlormequat residues in food commodities through the UK surveillance programme, and for cereals, the carry-through into a number of processed cereal-based foods has been followed. A downward trend of chlormequat residue levels in pears sampled between 1997 and 2002 was observed. This decline reflects changes that were introduced in European and national regulations and which have proven to be extremely effective in reducing both the frequency of detection and levels of chlormequat residues. Both acute and chronic risk assessments were undertaken based on aggregate dietary exposure data. Even when the highest residues observed were used in the calculations, the assessments showed that both the short- and long-term intakes for all consumer groups would be unlikely to cause adverse health effects and were therefore not of any cause for concern.

The effect of chlorocholine chloride (CCC) inclusion in the diets of growing hens on growth rate, oestrogen levels and the onset of lay.

A study was conducted to test the effect of chlorocholine chloride (CCC) on growth performance and the onset of laying in hens. One hundred and fifteen 3-week-old chickens were divided into four treatment groups of 39, 33, 31 and 12 chickens. They were placed on four dietary treatments consisting of 0 p.p.m. CCC (control), 5 p.p.m. CCC from 14 weeks of age (5 p.p.m. A), 5 p.p.m. CCC from the beginning (5 p.p.m. B), and 50 p.p.m. CCC from the beginning (50 p.p.m. B). The basal diets were formulated according to the growing period and were iso-nitrogenous and iso-energetic. The crude protein content was 17.99% dry matter and 14.63% dry matter during the first 3-8 weeks and 9-20 weeks, respectively. The energy content was 12.7 and 12.75 MJ metabolisable energy (ME)/kg dry matter for the respective two growth phases. Feed intake, bodyweight changes and egg production were measured. Blood samples for oestrogen determination were collected weekly from the 15th week until the first egg was laid. Depressive effects of 50 p.p.m. CCC on bodyweight gain during weeks 3-8 and feed efficiency over the whole period were observed. There were no treatment differences (p > 0.05) on feed intake, bodyweight gain during weeks 9-20 and age at the point of lay. CCC inclusion at 50 p.p.m. significantly (p < 0.05) stimulated the oestrogen concentration at 17 and 18 weeks of age, and was 65% higher than the control at 18 weeks.