Impact of predigestion feed on the growth of tilapia (Oreochromis niloticus)

The addition of simplified feed or predigestion feed is one of the alternative solutions in helping the process of utilizing feed by tilapia seeds with incomplete digestive tract conditions or limited secretion of digestive enzymes. The purpose of this study was to analyze the impact of predigestion feed on the growth of tilapia (Oreochromis niloticus). The design used in this study was a completely randomized design (CRD) with treatments in the form of differences in pancreatic enzyme concentrations (0%, 3%, 6%, and 9%) with 3 replications each. Parameters observed include the coefficient of diversity, specific growth rate (SGR), and feed efficiency. The results of this study showed that the lowest coefficient of diversity, the highest specific growth rate, and the highest feed efficiency were owned by the 9% treatment with a value of 16.07%, 4.95 %/day, and 84.02%, respectively. Provision of predigestion feed on tilapia fry significantly affected the growth of tilapia (Oreochromis niloticus). Provision of predigestion feed with an enzyme concentration of 9% gave optimal results.


Introduction
Tilapia (Oreochromis niloticus) is a consumption fish that is widely cultivated in Indonesia.The increase in production cannot be separated from the availability of tilapia.Tilapia in the early stages are susceptible to environmental changes and infection by pathogenic microbes.Strengthening the condition of the fish body is an effort that needs to be done, among others, by providing easily digestible feed [1].The addition of simplified feed or predigestion is an alternative solution in helping the process of utilizing tilapia with incomplete digestive tract conditions or limited secretion of digestive enzymes.The addition of enzymes from outside the body or exogenous enzymes through feed is expected to help the process of digestion and absorption of nutrients.After being relatively large, tilapia can utilize the feed optimally [2].
The pancreas is a digestive organ that functions in secreting digestive enzymes and plays a role in hydrolyzing feed in the digestive tract [3].Pancreatic enzymes are easily available materials and easy to apply as exogenous enzymes added to fish feed, especially for fish seeds whose endogenous enzyme secretion is very limited.Pancreatic chicken enzymes contain various types of enzymes including amylase, lipase, and protease [4].The effectiveness of pancreatic enzymes in hydrolyzing artificial feed in fish can be evaluated using the parameters of the coefficient of fish diversity, daily growth, and feed efficiency.

Research procedure
Tilapia were kept aquarium measuring 30x40x30cm with a water volume of 30 liters.Each aquarium consists of 10 tilapias.Tilapia fish maintenance was carried out for 30 days.During the maintenance period, observations of water quality (temperature, dissolved oxygen, pH, alkalinity, and ammonia) were carried out in the morning, in addition to observations of fish biology (coefficient of diversity (every day), SGR (10 days), and feed efficiency (end of observation).This research method complies with animal research ethics in accordance with Regulations Indonesian Institute of Sciences Republic of Indonesia Number 19 Of 2019 About Research Ethics Clearance.

Data analysis
Data on physical and chemical parameters of water as well as biology of tilapia were statistically analyzed using a completely randomized design (ANOVA) analysis of variance (ANOVA) processed with SPSS (Statistical Product and Service Solutions) and Excel 2016 for Windows programs.Then the data was further analyzed by the Tukey test to know the difference between the mean values of the variables [5].

Physical and chemical parameters of water.
The growth of tilapia during rearing is influenced by the physical and chemical conditions of the rearing media.The physical and chemical conditions of the media water that are in accordance with the needs of tilapia will cause it to have optimum growth.The data on the physical and chemical parameters of water are presented in Table 1.The value of the physical and chemical parameters of the water in this study, based on Table 1, was in the tolerance range of tilapia.This causes the media for rearing tilapia to support the growth of tilapia.

Coefficient of variation (CV).
The coefficient of variation is usually called the coefficient of variation or Coefficient of Variation (CV).CV is used to describe the biometric diversity of tilapia.The coefficient of diversity in this study was specifically used for data on length and weight of tilapia.The coefficient of diversity data in this study is presented in Figure 1.The coefficient of variance in this study based on Figure 1 shows that the coefficient of variance decreases with increasing pancreatic concentration.The highest coefficient of variation was found in the 0% treatment with an average value of 28.72%, while the lowest coefficient of variation was in the 9% treatment with an average value of 16.07%.

Specific growth rate (SGR).
The specific growth rate (SGR) value is the percentage of fish weight gained per day during maintenance.The best treatment will have the highest SGR value.The SGR data in this study is presented in Figure 2. The specific growth rate in this study, based on Figure 2, shows that the value of the specific growth rate increased in line with the increase in pancreatic concentration.The highest specific growth rate value was owned by the 9% treatment with an average value of 4.95%, while the lowest coefficient of variance was owned by the 0% treatment with an average value of 2.61%.

SGR (%)
Coefficient of Diversity (%) 1260 ( 2023 Feed efficiency in this study, based on Figure 3, shows that the value of feed efficiency fluctuates as the concentration of pancreas increases.The highest feed efficiency value was owned by 9% treatment with an average value of 80.4%, while the lowest feed efficiency value was owned by 0% treatment with an average value of 48.8 %.

Discussion
Physical and chemical parameters of water (temperature, DO, pH, alkalinity, and ammonia) are key parameters in supporting the life of tilapia [7] [2].The value of the physical and chemical parameters of water in each treatment in this study was still in the optimum range of tilapia based on [6].This explains that the main effect on growth is the administration of pancreatic enzymes.Parameters that are indicators of the effect of pancreatic enzymes on the growth of tilapia in this study include the coefficient of diversity, growth rate, and feed efficiency.
The results showed that the highest value of diversity was owned by the 0% treatment, while the lowest coefficient of diversity was owned by the 9% treatment.The CV value which shows the treatment has a good impact is indicated by a low CV value.A low CV value means that the growth of tilapia is uniform and does not differ in size.This is in accordance with research related to the impact of temperature on CV, which obtained the result that the optimal temperature has a lower CV value compared to other temperatures [8].
Specific growth rate (SGR), describes fish growth based on changes in length and weight.The SGR in this study showed that the value of the Specific growth rate increased in line with the increase in the concentration of the pancreas.The high SGR value explains that the treatment has a big influence on the growth rate.Research related to the use of probiotics on the growth rate of tilapia showed that the addition of probiotics increased the growth rate of tilapia in accordance with this study [9].
Feed efficiency is the level of fish's ability to utilize the given feed.The further analyzed parameter is feed efficiency [10].Feed efficiency in this study fluctuated with increasing pancreatic concentration.The highest feed efficiency value was owned by 9% treatment, while the lowest feed efficiency value was owned by 0% treatment.The best treatment will have a high feed efficiency value.The high feed efficiency explains that the feed provided is utilized by tilapia for growth and is not wasted in the rearing media.Research related to the effect of feeding rate on the efficiency of tilapia seed feed obtained optimal FR results to increase the value of feed efficiency [1].Feed Efficiency (%)

Conclusion
Feeding treatment with pancreatic enzymes as much as 9% is the best treatment in supporting the growth of Tilapia, based on the low coefficient of diversity, the value of growth rate, and high feed efficiency.

Figure 1 .
Figure 1.The coefficient of variation of tilapia.

Table 1 .
Physical and chemical parameters of tilapia seed rearing media.