Patent CA-2320687-A1 (CA)
Title: Multi-purpose model and analyzer for feed enzymes
Inventor: MARQUARDT RONALD R
IPC: A23K50/75
Filed: 2000-09-21
Abstract: We hypothesized that a log-linear model could be used to predict and evaluate the response of chicks to a dietary enzyme supplementation and that an in vitro dietary viscosity assay could be used in conjunction with the model as the predictor or evaluator. The results demonstrated that the model was able to accurately predict the response of chicks fed diets containing the different amounts of an enzyme and different proportions of two cereals. The slope of the model was a measure of the efficacy of the feed enzyme. The efficacy, in turn, was able to correctly evaluate the effects of different feed enzymes when added to a diet and to identify the most suitable target cereal for an enzyme. No other model, as far as the authors are aware of, are able to achieve this accuracy. In addition, a Multi-purpose Enzyme Analyzer has been developed based on the model. The analyzer was able to determine the optimal amount of an enzyme and a substituted cereal that should be used in a diet for maximal profit, and to determine the amounts and the expected prices of the enzyme and cereal that will yield a given profit. Also, the effect of a feed enzyme could be evaluated using maximal profit as a criterion. Therefore, the most profitable among several feed enzymes and the cereal that should be used for a given feed enzyme could be determined. Furthermore, a dietary viscosity assay has been developed. The results indicated that there was a linear relationship between the log of dietary viscosity change measured by the assay and the log of amount of enzyme added to a diet (r2 = 0.99, P < 0.005). The values from the assay were able to predict the response of chicks to a feed enzyme and also evaluate the efficacy of different feed enzymes, especially for those enzymes that hydrolyzed the viscous compounds in the diet. These studies demonstrated that the response of chicks to a feed enzyme and the efficacy of the enzyme could be accurately predicted and evaluated on the basis of a log-linear model using different criteria (performance and economic return), and different type of studies (in vivo and in vitro).      Key Words: Log-linear model, Enzymes, Poultry, Feeds Our previous studies demonstrated that a log linear equation could be used to accurately predict chick performance when a crude enzyme was added to a diet and that a single value, the slope of the log-linear equation, provided a measure of the efficacy of different feed enzymes. The objective of the current study was to determine if the model could also be used to establish a profit function for carrying out a least-cost analysis and to develop a software package, a Multi-purpose Enzyme Analyzer (MPEA), for evaluating and estimating the effect of enzymes when added to poultry feeds based on their profitability. The results demonstrated that there were high correlations between the efficacy of different feed enzymes (B  values, the slopes of the equations) and the maximal profits that were obtained when feed enzymes were added to a barley-based diet (r2 = 0.99, P < 0.2171). This suggested that the maximal profits as well as their B values could evaluate the effectiveness of different enzyme preparations. In contrast, there was a low correlation between the B values and the maximal profits when a feed enzyme was added to different cereal-based diets (r2 = 0.61, P = 0.2171). This suggested that there is not always a close association between efficacy of an enzyme when added to different cereals and the corresponding profitability. The MPEA was highly versatile as any combination of inputs such as the amounts of a feed enzyme and a substituted cereal required to yield a certain profit level could be determined. In addition, the results demonstrated that the price that should be paid for a feed enzyme when added to a given diet or for a cereal when used with a given feed enzyme to yield a maximal level profit could be also evaluated. In conclusion, the maximal profit that is obtained with a feed enzyme when added to a diet can become a useful standard to accurately evaluate different feed enzymes when added to a diet, to select the most profitable cereal for a given feed enzyme, to determine the optimal amounts of a feed enzyme and/or a cereal, and even to estimate the alternate price that could be paid for a feed enzyme and a cereal. Therefore, the MPEA provides a useful tool for the nutritionists in the enzyme and feed industry for evaluating the most economic use of feed enzymes and cereals in poultry diets. (Key words: feed enzymes, maximal profit, profit functions, log linear model)