การเสริมสร้างโปรตีนไฮโดรไลเซตจากเศษเหลือเห็ดนางฟ้าในอาหารที่ใช้วัตถุดิบจากพืชเป็นหลักสำหรับปลาสวายปรับปรุงสายพันธุ์

Abstract

The research was divided into 2 experiments. Experiment 1 studied on a suitable level of fishmeal replacement with plant mixtures in hybrid Pangasius (Pangasianodon gigas × P. hypophthalmus) diet. Plant protein mixtures (soybean meal, peanut meal and wheat gluten) partly replaced decreasing levels of fishmeal: 0 (control), 25, 50, 75 and 100%, respectively. The experiment was conducted in 5 treatments with 3 replications (T1-T5). Feeding trial was 60 days, twice daily at 9.00 am and 4.00 pm. to evaluate the effects of diet on growth performance, immune system, and digestive enzyme activity. Initially, fish weighed 3 grams. The results showed no significant differences (P>0.05) among fish fed the (0 (control), 25, 50 and 75%) replacement diets in growth performance and feed utilization: weight gain, specific growth rate, survival rate, feed consumption and feed conversion ratio, blood parameters and digestive enzyme activitieas. However, the fish fed 100 % plant mixtures had significantly lower (P<0.05) growth performance and feed utilization. Nonetheless, plant protein mixtures can be included at the level of up to 75% without any adverse effects on growth performance, feed efficiency, and health status. But the apparent net protein utilization in fish fed the 50% plant mixture replacement diet was higher (P<0.05) than the other groups. In conclusion, the most efficient formula was the 50% plant mixture replacement diet for the hybrid Pangasius catfish. Experiment 2 studied on the optimal condition to produce protein hydrolysate from grey oyster mushrooms (Pleurotus sajor-caju (Fr. Singers)) and concluded that it is pH 7, at 50°c, for 3 hours with 2% enzyme concentration. The optimal level for the highest degree of hydrolysates was 139.62±38.80%. Supplementation of mushroom protein hydrolysate (MPH) in given results from experiment 1 diets. As the results show, plant mixture ingredients contain anti-nutrition factors and decreased feed attraction. Thus, the protein hydrolysate stimulated consumption and increased feed utilization. The experimental diets were as follows: control group, 50% plant protein mixtures +2.5% MPH, 50% plant protein mixtures + 5% MPH, 75% plant protein mixtures + 2.5% MPH and 75% plant protein mixtures + 5% MPH (T1-T5, respectively). Fish with an initial weighed 5.25 grams were fed two times daily, at 9.00am and 4.00pm. The results on growth performance and feed utilization: weight gain, specific growth rate, survival rate, feed consumption feed conversion ratio and protein efficiency ratio, were not significantly different (P>0.05), but apparent net protein utilization was significantly higher (P<0.05) in the T4 diet group (75% plant protein mixtures + 2.5% MPH). Blood parameters such as red blood cell count and white blood cell count were not significantly different (P>0.05). However, lysozyme activity was significantly higher (P<0.05) in the T5 diet group (75 % plant protein mixtures + 5% MPH). Digestive enzyme activities in terms of trypsin and chymotrypsin were not significantly different (P>0.05). Nevertheless, lipase and amylase activity from intestines of fish fed MPH supplemented diets was higher than the control group (P<0.05). TBARs were significantly lower (P<0.05) in the fillet of fish fed with MPH diet groups than the control group. Furthermore, the added of 2.5% MPH in plant mixture replacement at 50 and 75% feed were no significant differences (P>0.05) of color tests in fillets. Futhermore, supplementation at 2.5% MPH in hybrid Pangasius catfish, established protein utilization from plant protein mixtures as well as control diet group, enhance enzyme activity and fillet product quality