Carp polyculture is the most common, popular, and successful aquaculture system in Nepal. Including mono-sex Nile tilapia in carp polyculture could enhance fish productivity. This present LEE work was conducted at the Fish hatchery complex of Fisheries Program, Agriculture and Forestry University, Rampur, Chitwan, in a cemented tank of area 25 m² for 26 days to study the carp and mono-sex Nile tilapia in a polyculture system.

The pond was fertilized using urea and DAP at the rate of 4,7 g/m²/week and 3.5 g/m²/week respectively. Fishes except Grass carp were fed twice daily with the pellet made from mustard oil cake and rice bran mixed at a 1:1 ratio at the rate of 5% BW. Grass carp were fed with duckweed at a rate of 50% BW twice a day from 7:30 am to 8 am and 1:30 pm to 2 pm. Water quality parameters i.e., water temperature, transparency, water depth, dissolved oxygen, and pH and were monitored daily while total alkalinity was monitored weekly. Sampling of fish was done fortnightly to check fish growth and adjust feed quantity.

All the water quality parameters were within the optimal range of fish production except for DO which was very high during the afternoon. The extrapolated GFY and NFY were 14.5 t/ha/yr and 9.6 t/ha/yr, respectively. The overall survival of fish was 87% and AFCR was 1.4. The total variable cost and the production cost was NRs. 220/kg. Fishes were transferred to the Aquaculture farm, assuming the selling rate NRs. 300/kg. This makes the total gross return was of NRs. 875, making a total net profit of NRs. 327. The B: C ratio was 1.59. From this LEE work, it was concluded that carp and mono-sex Nile tilapia polyculture is a reliable and profitable venture to carry out.

Excerpt

1 INTRODUCTION
- 1.1 General introduction
- 1.2 Objectives
  - 1.2.1 General objective
  - 1.2.2 Specific objectives
- 1.3 Limitations of the study
2 LITERATURE REVIEW
- 2.1 Global status of aquaculture
- 2.2 Status of aquaculture in Nepal
- 2.3 Carp polyculture
- 2.4 Principle of carp polyculture
- 2.5 Pros and cons of carp polyculture
  - 2.5.1 Pros of polyculture
  - 2.5.2 Cons of polyculture
- 2.6 Carp-Nile tilapia polyculture
- 2.7 Culture species
- 2.8 Stocking
- 2.10 Water quality requirements for carps and Nile tilapia
- 2.11 Feed and feeding
  - 2.11.1 Natural food
  - 2.11.2 Supplementary food
  - 2.11.3 Liming
  - 2.11.4 Fertilization
  - 2.11.5 Yield and FCR
  - 2.11.6 Economics of carp and Nile tilapia polyculture
3 MATERIALS AND METHODS
- 3.1 LEE site
- 3.2 Tank preparation
- 3.3 Tank management
- 3.4 Fish sampling
- 3.5 Fish harvesting
- 3.6 Marketing of fish
- 3.7 Analytical methods
4 RESULTS
- 4.1 Water quality
- 4.2 Fish growth and production
- 4.3 Gross margin and Fish marketing
5 DISCUSSION
- 5.1 Water quality
- 5.2 Growth and yield of fish
- 5.3 Gross margin and fish marketing

Objectives and Key Themes

This thesis aims to investigate the feasibility and efficiency of carp and mono-sex Nile tilapia polyculture in a cemented tank. The study explores various aspects of this polyculture system, from tank preparation and management to fish growth, production, and economic viability.

The effectiveness of polyculture systems for fish production.
Water quality management in intensive fish farming.
Growth rates and yields of different fish species in a polyculture environment.
Economic analysis of carp and Nile tilapia polyculture.
Sustainable aquaculture practices in Nepal.

Chapter Summaries

1 INTRODUCTION: This introductory chapter sets the stage for the research by providing a general overview of aquaculture, its global and national (Nepal) context, and the specific focus on carp and Nile tilapia polyculture. It clearly defines the general and specific objectives of the study, outlining the parameters and goals for investigating the effectiveness of this particular polyculture system within a controlled environment. It also acknowledges the limitations imposed by the research setting and methodology.

2 LITERATURE REVIEW: This chapter presents a comprehensive overview of existing literature related to aquaculture practices. It covers the global and Nepalese status of aquaculture, delving into the principles, advantages, and disadvantages of carp polyculture. The chapter extensively explores carp-Nile tilapia polyculture, detailing the characteristics of each species involved, optimal stocking densities, water quality parameters, feeding strategies (both natural and supplementary), and a detailed analysis of the economic aspects of this type of polyculture system. This review serves as the foundation for the research methodology and expected outcomes.

3 MATERIALS AND METHODS: This chapter meticulously describes the research methodology employed. It details the selection of the research site, the preparation of the cemented tank (including draining, drying, liming, and fertilization), and the stocking of fingerlings. The chapter thoroughly outlines the daily operations and monitoring protocols followed throughout the study, including feeding, fertilization practices, regular water quality monitoring, fish sampling procedures, and the marketing strategies employed after harvest. Finally, it describes the analytical methods used for assessing fish growth parameters, conducting a gross margin analysis, and applying statistical analyses to the obtained data.

4 RESULTS: This chapter presents the findings of the research, detailing the collected data on water quality parameters throughout the study period. This is followed by a comprehensive overview of the growth and production data for each fish species involved in the polyculture system (silver carp, bighead carp, grass carp, rohu, common carp, and Nile tilapia). Finally, it presents results concerning the overall gross margin and fish marketing analysis.

5 DISCUSSION: This chapter provides an in-depth analysis and interpretation of the results presented in Chapter 4. It discusses the observed water quality parameters and evaluates their impact on fish growth and overall productivity. A detailed discussion is dedicated to analyzing the growth rates and yields of the different fish species, highlighting any significant findings or patterns. The economic viability of the polyculture system is also assessed by reviewing the gross margin and fish marketing results. This chapter critically evaluates the effectiveness of the methods employed and potential improvements for future research.

Keywords

Carp polyculture, Nile tilapia, aquaculture, fish farming, water quality, fish growth, yield, economic analysis, sustainable aquaculture, Nepal.

Frequently Asked Questions: Carp and Mono-sex Nile Tilapia Polyculture in Cemented Tanks

What is the main focus of this research?

This research investigates the feasibility and efficiency of carp and mono-sex Nile tilapia polyculture in a cemented tank. It explores various aspects, from tank preparation and management to fish growth, production, and economic viability.

What are the key themes explored in this study?

The study explores the effectiveness of polyculture systems for fish production, water quality management in intensive fish farming, growth rates and yields of different fish species in a polyculture environment, economic analysis of carp and Nile tilapia polyculture, and sustainable aquaculture practices in Nepal.

What are the specific objectives of this research?

The research aims to determine the effectiveness of this polyculture system, analyze water quality management within the system, assess growth rates and yields of different fish species, and conduct an economic analysis of the polyculture system. The study also considers sustainable aquaculture practices in the Nepalese context.

What is included in the Literature Review chapter?

This chapter provides a comprehensive overview of aquaculture globally and in Nepal, focusing on carp polyculture principles, advantages, and disadvantages. It details carp-Nile tilapia polyculture, including species characteristics, stocking, water quality, feeding strategies, and economic aspects.

How does the study describe its methodology (Materials and Methods)?

The methodology section details site selection, tank preparation (including liming and fertilization), stocking procedures, daily management, water quality monitoring, fish sampling, harvesting, marketing strategies, and the analytical methods used for data analysis (fish growth, gross margin, statistical analysis).

What results are presented in the study?

The results chapter presents data on water quality parameters, fish growth and production for each species (silver carp, bighead carp, grass carp, rohu, common carp, and Nile tilapia), and a gross margin and fish marketing analysis.

How are the results discussed and interpreted?

The discussion chapter analyzes the results, focusing on water quality's impact on fish growth, growth rates and yields of each species, and the economic viability of the polyculture system. It also critically evaluates the methods used and suggests improvements for future research.

What are the key limitations acknowledged in the study?

The introduction chapter acknowledges limitations imposed by the research setting and methodology, though the specific limitations are not explicitly detailed in the provided preview.

What are the keywords associated with this research?