Pangasius fish (Pangasius sp.) are recognized as a fishery commodity with significant potential in Indonesia. With the increasing market demand, especially for export purposes, this fish has become a top choice for many fish farmers in Indonesia. Additionally, pangasius fish exhibit good resilience to environmental conditions, making them easier to cultivate compared to other fish species. However, to achieve optimal hatchery results and high-quality fry, the selection and management of pangasius broodstock are crucial aspects that cannot be overlooked.
Healthy and superior pangasius broodstock are the foundation of successful hatchery operations. Well-selected broodstock will produce fry that not only have a high survival rate but are also capable of rapid growth and respond well to feed. Therefore, the selection process of pangasius broodstock must be conducted meticulously, taking into account various factors such as age, weight, and the physical health of the broodstock. Without proper selection, the entire hatchery process can be disrupted, potentially reducing the quality and quantity of the fry produced.
In addition to broodstock selection, maintenance management is also a key factor in determining hatchery success. Maintaining pangasius broodstock requires special attention to several aspects, including providing appropriate feed, managing water quality, and handling pests and diseases. Hence, this article will thoroughly discuss the criteria for selecting good pangasius broodstock, as well as various management steps that need to be implemented in broodstock maintenance.
Criteria for selecting superior pangasius broodstock
Pangasius broodstock ready for breeding has specific criteria that must be met. Rapid growth, no defects, aggressiveness, and good health characterize healthy and superior broodstock. Broodstock selection is based on gonad maturity, meaning the eggs in the female broodstock are mature and ready to be fertilized by sperm from the male broodstock.
In pangasius fish, the ideal female broodstock is at least 2.5 years old with a body weight between 2.5 and 3 kilograms per fish. Meanwhile, male broodstock should be at least 2 years old with a body weight between 2 and 2.5 kilograms per fish. The physical characteristics of female broodstock ready for breeding include a soft and smooth abdomen, enlarged towards the anus, and a swollen, dark red urogenital area. On the other hand, male broodstock have a more slender and elongated posture, with a dark red color in the urogenital region and the release of thick white fluid (sperm) when the abdomen near the genital area is pressed.
A pair of broodstock pangasius fish undergoing striping treatment: BPBAT Sungai Gelam
To ensure that the eggs in the female broodstock are mature, egg diameter measurements and observation of egg nucleus movement can be conducted. Mature eggs are generally uniform in size with a diameter of more than 1.0 mm, and more than 80 percent of their nuclei move to the edge in a saline solution.
Pangasius broodstock maintenance management
Pangasius broodstock maintenance management is a crucial aspect of hatchery operations aimed at improving efficiency and productivity. Proper maintenance encompasses various factors, ranging from providing high-quality feed to managing an optimal environment. Good maintenance will result in high-quality fry in terms of both quantity and quality. Here are the essential steps in pangasius broodstock maintenance management:
Using appropriate rearing containers
Ponds are the most suitable containers for rearing pangasius broodstock. Commonly used containers are concrete ponds with earthen bottoms or floating net cages (KJA). Each type of container has its advantages and disadvantages. Concrete ponds with earthen bottoms have the benefit of being suitable for flat land surfaces, away from external water pollution, and natural products that can enhance fish yield. However, the disadvantages of these ponds are the possibility of significant water quality changes between day and night, as well as the need for periodic sludge removal.
The sorting process of pangasius broodstock candidates in floating net cages at Lake Tondano, North Sulawesi: BPBAT Tatelu
On the other hand, floating net cages have advantages in terms of small volume with high fish density, simple and inexpensive technology, and ease of management. However, there is a risk of fish escaping into river waters and the potential for unexpected water pollution.
Optimal feeding practices
Feeding is a vital element in maintaining the health and readiness of pangasius broodstock for the spawning process. The feed provided must have a balanced nutritional content, especially in terms of protein content, which is crucial for supporting the reproductive process. Pangasius broodstock require feed with a high protein content, around 35 percent, which plays a role in repairing body tissues and ensuring optimal gonad growth. This protein content not only aids in producing quality eggs but also ensures that the broodstock has sufficient energy to undergo the spawning process smoothly. Furthermore, the quality of the feed provided also directly impacts the overall health of the fish, helping them cope with stress and maintain their immune system against various diseases.
In addition to quality, the quantity of feed provided must also be adjusted to the fish's body weight to ensure that nutritional needs are met without overfeeding, which can cause health problems. For example, pangasius broodstock weighing between 500 and 1,000 grams require feed amounting to 2 percent of their body weight daily. Meanwhile, for fish weighing more than 2,000 grams, the feed provided is only about 0.8 percent to 1 percent of their body weight. This feeding should be done regularly, usually two to three times a day, paying attention to the fish's physical condition and their response to the feed.
Besides being adjusted to the fish's body weight, feeding pangasius broodstock should also consider adequate protein content. Protein is the main component that supports fish growth and reproduction, so the protein ratio in the feed must be carefully calculated. For instance, if the protein ratio in feed 1 is 1.4 times 0.8 percent, the new feed ratio becomes 1.12 percent. This ratio means that the feed provided must contain 1.12 percent protein of the total fish biomass. This calculation is important to ensure that each broodstock receives the right protein intake to support the spawning process and maintain overall health.
Feeding according to these protein requirements is typically done 2 to 3 times a day, depending on the body size and appetite of the pangasius fish. The feeding frequency should also be adjusted to the fish's physical condition and the environment in which they are reared.
High-quality pangasius fingerlings from superior broodstock: KKP
Water quality management
Water quality is one of the most crucial factors in the success of pangasius fish farming. As living creatures entirely dependent on the aquatic environment, pangasius fish require stable and suitable water conditions to support their growth, health, and reproductive processes. The water used as the cultivation medium must meet specific quality standards that encompass various important parameters, such as temperature, pH, and dissolved oxygen content. Each of these parameters has a direct impact on the fish's metabolism, appetite, and their ability to reproduce.
Water temperature is one parameter that significantly affects the appetite and activity of pangasius fish. The optimal water temperature for pangasius fish ranges from 22-29 °C, where within this temperature range, the fish usually exhibit a better appetite and are more active in seeking food. This water temperature generally occurs in the morning and evening, so fish farmers often adjust feeding times based on daily temperature fluctuations. Temperatures that are too low or too high can cause stress to the fish, which will ultimately disrupt their growth and reproduction processes.
In addition to temperature, water pH is also a factor that must be well-maintained. The ideal water pH for pangasius fish farming ranges from 6.5 to 8.5. A pH that is too acidic or too alkaline can cause physiological disturbances in the fish, such as gill damage, which impairs their ability to absorb oxygen from the water. Dissolved oxygen content is also a major concern in water quality management. Sufficient oxygen in the water is vital to support the fish's respiration process. Pangasius fish require dissolved oxygen with a minimum concentration of 5 mg/L to live and reproduce well. Low dissolved oxygen content can cause the fish to become lethargic, lose appetite, and in more severe cases, can lead to mass mortality.
The basic principle in water management is to introduce beneficial substances and remove harmful substances from the cultivation container. Oxygen (Oâ‚‚) is one of the essential substances that must always be available in sufficient quantities in the water, while substances like ammonia (NH3), carbon dioxide (COâ‚‚), and other waste products must be removed as they can be toxic and detrimental to fish health. This process is usually carried out through periodic water replacement and using aeration systems to increase dissolved oxygen levels. The water used for maintaining pangasius broodstock should also come from a clean source, such as a borehole or unpolluted river water, to ensure that water quality is maintained.
Pest and disease management in pangasius fish
Pest and disease management in pangasius fish farming is a crucial aspect that should not be overlooked, especially due to its significant impact on the success of fish breeding and rearing. There are two main approaches to dealing with pests and diseases: prevention and treatment. Prevention is a highly recommended step because it is not only more effective in the long run but also more economical. Through prevention, pest and parasite attacks can be minimized before they have a chance to damage the fish population. Prevention methods include implementing good sanitation, maintaining water quality, and using high-quality feed. In this way, the risk of fish contracting diseases can be minimized without causing side effects, both for the fish themselves and for humans who consume them.
A view of the pangasius fish pond environment in Kampung Patin, Koto Masjid Village, Kampar, Riau: KKP
Fish diseases often arise as a result of complex interactions between the environment, the fish's health condition, and the pathogenic organisms causing the disease. A poor environment, such as deteriorating water quality or unclean pond conditions, can trigger stress in fish, thereby lowering their resistance to disease attacks. Additionally, low-quality feed can cause fish to experience nutritional deficiencies, which in turn weakens their immune systems. When these conditions occur, pathogenic organisms like bacteria, viruses, or parasites can more easily attack and cause diseases in the fish.
Although prevention is the ideal step, sometimes fish can still be affected by pests or diseases. In such situations, treatment must be carried out immediately to save the fish population. This treatment can involve using medications specifically designed to address certain diseases or through improving environmental conditions that allow the fish to recover naturally. However, it's important to remember that treatment is not always the desired solution as it often incurs additional costs and can leave chemical residues in the fish that are potentially harmful to consumers.
