Mối tương quan giữa phương pháp in vivo và in vitro trong việc xác định protein tiêu hóa trong thức ăn tôm thẻ chân trắng (Litopenaeus vannamei)

Protein digestibility is an important indicator in quality assessment for aquafeed ingredients. Many in vitro assays have been developed for quick estimation of protein digestibility and replacement of feeding trials. pH stat, pH drop and pepsin digestibility with single/multi enzyme, one/two step digestion have been studied for mammals from 1970s. These methods

have been found to correlate well with in vivo protein digestibility. However, to date, the application of in vitro assays for shrimp and fish is still not populated. Currently, Research Institute for Aquaculture No. 2 has performed a research on quick procedures evaluating protein digestibility of feeds for white leg shrimp. The objective of this research is to find a diagnostis tool to support authority departments in quality control of commercial aquafeeds. In the study, five in vitro methods (including pH drop with 3 or 4 enzyme, pH stat with 3 or 4 enzyme and pepsin digestibility) were investigated. The results showed that only the threeenzyme pH stat method was well correlated with in vivo technique (R2 = 0,6664). The other methods had a low regression coefficient between in vitro and in vivo protein digestibility (R2 < 0,13). However, the regression coefficient of the three-enzyme pH stat system is still not high for utilization. Therefore, it is necessary to conduct more experiments in order to increase the correlation and accuracy.