A discounted least squares quadratic growth prediction model for use in 2 year toxicity studies

Weekly weighings of the laboratory rats are required to determine the correct dosage for mixing in the food. This creates problems in that the food mixing must be done immediately after the weighings and staff are often heavily taxed to perform the task. A discounted least squares growth prediction model allows for prediction of weights a week ahead of time, obviating the necessity for instantaneously processing the weight data. When dosages were prepared based on these predictions, for 10 treatment combinations 100% of the doses proved to be within 8-0% of the required dosage; 98-4% were within 5% of the required dosage; 78-7% were within 2% of the required dosage; and 51-6% were within 1% of the required dosage. The quadratic weight prediction model can also be incorporated into a model for predicting food consumption.