Effect of gibberellic acid on broiler chickens performance and some metabolic parameters

The mitigating effect of Spirulina (Arthrospira platensis) on the hemotoxicity of gibberellic acid on juvenile tilapia (Oreochromis niloticus)

The use of plant growth regulators has led to environmental contamination of water bodies that occur adjacent to agricultural areas. Some of these chemicals are bioactive, not only to plants, but also to non-target exposed biota, namely of the aquatic compartment. Previous work demonstrated the establishment of hepato- and nephrotoxic effects in juvenile tilapia (Oreochromis niloticus) exposed via aquatic media to gibberellic acid (GA3), which is among the most used plant growth regulators, in agricultural practices. Here, we investigated the effect of GA3 on hematological indices, poikilocytosis, nuclear abnormalities, and genotoxic indices measured in Nile tilapia (Oreochromis niloticus), as well as the putative protective effects of dietary supplementation of Spirulina (Arthrospira platensis). Fish were evenly assorted into 5 groups: group I served as a control, and groups II-V were fed diets supplemented with Spirulina at rates of 0 g/kg, 5 g/kg, 20 g/kg, and 100 g/kg, respectively, for 2 months before being exposed to 150 mg/L GA3. The results revealed that GA3 exposure decreased significantly all hematological indices (P < 0.05), except leucocytes and mean corpuscular hemoglobin concentration (MCHC), compared to the control group (P > 0.05). GA3 exposure increased significantly the percentage of nuclear abnormalities, altered erythrocytes and the percentages of tail DNA, compared to the control group (P < 0.05). Spirulina supplementation restored the hematological, poikilocytosis, nuclear abnormalities, and the percentages of tail DNA to near normal levels. The 100 g/kg SP treatment was the most effective in attaining such effect, showing concentration-dependency. The present study reinforces our findings of the toxicity of GA3 on O. niloticus and suggests that the addition of Spirulina to fish diet can mitigate the hemotoxic effects of GA3.

Oxidative stress induced by gibberellic acid in bone of suckling rats

The present study investigates the bone maturity of suckling rats whose mothers were treated with gibberellic acid (GA(3)). Female Wistar rats were divided into two groups: group I that served as controls and group II that received orally GA(3) (200 ppm) from the 14th day of pregnancy until day 14 after delivery. In the GA(3) group, an increase in body and femur weights as well as in femur length of pups was noted when compared to controls. Lipid peroxidation was demonstrated by high femur malondialdehyde levels, while superoxide dismutase, catalase, glutathione peroxidase activities, glutathione and vitamin C levels in femur decreased. GA(3) caused a decrease in calcium and phosphorus levels in bone. The calcium concentration in plasma increased and the phosphorus concentration decreased, while urinary levels of calcium decreased and those of phosphate increased. Moreover, plasma total tartrate-resistant acid phosphatase and total alkaline phosphatase increased. Bone disorders were confirmed by femur histological changes.