Effects of two large doses of equine recombinant growth hormone on clinical, haematological and serum biochemical variables in adult horses.

The research studied the effects of two large doses of equine recombinant growth hormone on horses’ clinical, haematological, and serum biochemical variables. The study found that the administration of up to five times the recommended dose had no significant effects on these variables, suggesting a wide margin of safety for this treatment.

Study Design and Methodology

• The study employed a duplicated Latin square design involving six horses—three Thoroughbreds and three Standardbreds—all aged between 12 and 17 years.
• Two horses were randomly assigned to each of three groups. Over the course of three days, each pair of horses received one of two dosages of growth hormone or a saline placebo. The selected dose rates were 50 micrograms/kg and 100 micrograms/kg.
• The study aimed to ensure that by the end of the experiment, all horse pairs had received both dosages and the saline placebo. Clinical examinations were conducted and venous blood samples were drawn for complete blood count and serum biochemical analysis both before administration of the growth hormone and at 1, 2, 3, 4, 6, 8, and 24 hours after injection.
• The acquired data were then analyzed using a repeated measures analysis of variance to assess the effects of the dose and time.

Results of the Study

• The analysis showed that time had an effect on a number of the studied clinical, haematological, and serum biochemical variables.
• Significant effects of the growth hormone were observed on heart rate and serum glucose concentration, though the values for both variables remained within the reference range.

Conclusions Drawn from the Study

• The study concluded that equine recombinant growth hormone has a wide margin of safety. Even administering up to five times the recommended dose had no significant effect on the clinical, haematological, or serum biochemical variables in the horses.
• The results suggest that the equine recombinant growth hormone could potentially be used in larger doses without causing adverse effects, demonstrating its high safety level.