The key to the profitability of yellow catfish farming lies in reducing the feed conversion ratio

The key to the profitability of yellow catfish farming ---- how to reduce the feed conversion ratio

In aquaculture production, the feed conversion ratio is one of the main factors determining the level of farming profitability. In the future farming process of marine and seawater aquatic products, the cost of feed accounts for more than 60% of the farming cost. Therefore, the correct use of feed and its results will play a decisive role in the process of aquatic product farming. Only by fully leveraging the utilization rate of feed, reducing the cost of using feed, and achieving higher yields with a lower feed conversion ratio can profits be maximized.

In aquaculture production, the feed conversion ratio is one of the main factors determining the level of farming profitability. Feed cost accounts for an average of 40%-50% of farming costs, and in high cases reaches around 65%. Therefore, for farmers to achieve better economic returns, reducing feed costs is extremely important. Some people always assume that if the feed price is low, the investment is small and the cost is low, and this view is especially prominent in economically underdeveloped areas, but the results of feed use are not like this. Please look at the example above.

Feed cost per unit of fish production = feed conversion ratio x feed price

From this it can be seen that the feed cost per unit of fish production is determined by the feed conversion ratio and the feed price. When choosing feed, there are the following two options:

A: The feed conversion ratio for yellow catfish is relatively high, but the feed price is relatively low (for example, Company A's yellow catfish feed, feed conversion ratio 1.85, price 6000 yuan per ton).

B: The feed conversion ratio for yellow catfish is low, but the price is relatively high (for example, Company B's yellow catfish feed, feed conversion ratio 1.45, price 7400 yuan per ton).

1. Without considering the influence of other factors, the results of their use:

A: Feed cost per unit of fish weight gain = 1.85 x 6 yuan/kg = 11 yuan/kg

B: Feed cost per unit of fish weight gain = 1.40 x 7.4 yuan/kg = 10 yuan/kg

That is, feed B can save 1 yuan in cost per kilogram of fish produced compared with feed A, and 1000 yuan in cost per ton of fish produced, so the cost savings in large-scale farming are considerable.

From the above results it can be seen that when choosing feed for feeding, choosing feed with a low feed conversion ratio but a high price, as long as its quality is good, actually results in a lower cost of fish production, and vice versa. Therefore, the correct method of using feed in yellow catfish farming has a decisive influence. Only by fully leveraging the utilization rate of feed can the cost of using feed be reduced.

The feed conversion ratio is also called the feed coefficient. It refers to the ratio between the amount of feed fed and the total net weight gain of the farmed subject. The smaller the ratio, the less feed is used to add each unit of aquatic product output. Therefore, the smaller the ratio, that is, the lower the feed conversion ratio, the lower the feed cost and the stronger the economic returns of farming. So how should the feed conversion ratio be reduced in yellow croaker farming?

Improve farming methods and adopt new farming techniques

With the advancement of science and technology, new high-yield farming techniques keep emerging. For example, in current seawater farming, adding self-purification of water quality during the farming process optimizes the farming water environment, further promotes the feed conversion rate, and further lowers the feed conversion ratio. In addition, in marine fish farming, adopting cage farming techniques, and in shrimp farming adopting the technique of fertilizing the water for shrimp fry to enter the pond and cultivating palatable plankton for the shrimp to feed on, are all effective farming techniques that lower the feed conversion ratio and increase farming profitability.

Establish good water area environmental conditions

The environmental conditions of a healthy ecological farming water area mainly include water quality, bottom sediment, and the natural biological environment in the water, as well as external pollution and self-pollution during the farming process and other factors. At present, poor water quality conditions generally exist in farming waters, mainly manifested in pesticide pollution, industrial three-waste pollution, toxic gas pollution produced by the decay of leftover feed during farming, pollution from excessive application of drugs for disease prevention and control, and toxic pollution produced by the decomposition of the excrement of farmed subjects. This causes various toxic and harmful substances in the farming water body to exceed standards, and the farmed subjects live long-term in a poor environment that is adverse or even life-threatening. Under such environmental conditions, even with high-quality feed that is comprehensive in nutrition and good in palatability, excellent feed returns will absolutely not be obtained, the feed conversion ratio is bound to remain high, and farming profitability is reduced.

Therefore, in aquaculture, we must first establish good water body environmental conditions, implement green ecological farming, and rationally use drugs for disease prevention and control, so that the farming water body has no pollution, no drug residues, and no harmful substances, and all chemical and biological indicators meet fishery water standards. Only by farming under such good water area environmental conditions can the feed conversion ratio be effectively lowered, the quality and quantity of products increased, and the goal of producing green aquatic food achieved, thereby strengthening the economic returns of farming.

Dissolved oxygen content in water

This is a major factor affecting the feed intake of farmed subjects and the digestion and absorption rate after feed ingestion, as well as the growth rate and the level of the feed conversion ratio. When the dissolved oxygen content in water is low, the appetite of farmed subjects declines, or they even refuse to eat; even if feed is ingested, it will cause low digestion and absorption rates, slowed growth rate, low feed utilization rate, and an increased feed conversion ratio. The feed conversion ratio of fish at a dissolved oxygen level of 3.0 mg/L is double that at 4.0 mg/L. When the dissolved oxygen content in water reaches above 4.5 mg/L, the increase in the fish's appetite is extremely obvious, and when it reaches above 5 mg/L, the feed conversion ratio reaches its lowest value. This is the fundamental reason why flowing water methods or aerators are adopted in high-yield or high-density farming. Therefore, when feeding feed, attention must be paid to the dissolved oxygen content in the water and changes in the weather. When the dissolved oxygen content in the water is low, the air pressure is low, and the weather is stuffy and fish are gulping at the surface, do not feed; wait until the situation improves before feeding. Generally, feed after two hours after sunrise, when the dissolved oxygen in the water reaches above 4 mg/L. Therefore, during the farming process, measures such as frequently injecting new water, regulating water quality, removing excess sludge, using aerators, and monitoring the physical and chemical indicators of water quality should be adopted frequently to achieve the goals of sufficient dissolved oxygen, reduced harmful gas content, favorable digestion and absorption, and a lowered feed conversion ratio.

When the dissolved oxygen content is above 5 mg/L, fish feeding is normal;

When the dissolved oxygen content drops to 4 mg/L, fish feed intake drops by 13%;

When the dissolved oxygen content drops to 2 mg/L, fish feed intake drops by 54%, growth is stunted, and fish begin to gulp at the surface;

When the dissolved oxygen content drops to 1 mg/L, fish and shrimp basically do not eat, and they float to the water surface, forming the phenomenon of gulping for air;

When the dissolved oxygen content drops to 0.5 mg/L, fish and shrimp will all suffocate and die within a few hours.

Adopt scientific and rational stocking techniques

Correctly selecting high-quality feed and setting a reasonable stocking density during the stocking process are major factors determining the feed conversion ratio. Therefore, we must first determine a suitable stocking density, that is, the optimal stocking amount, based on the local weather conditions, water quality conditions, and biological environment. If the density is too high, the water body is prone to oxygen deficiency, and harmful hydrogen sulfide and ammonia nitrogen will accumulate and increase; the farmed subjects living under such conditions grow in a poor water body environment, and the feed conversion ratio is bound to rise. Conversely, if the density is too low, the potential of the water body cannot be fully utilized, the output value and returns decline, and the feed conversion ratio likewise rises.

In addition, the stocking size and quality of the farmed subjects are the second factor determining the feed conversion ratio in stocking techniques. The overall requirements for the size and quality of stocked species are: uniform specification, free of disease and injury, pure germplasm, and strong and lively. If the quality of the stocked species is good and the body is strong, then the appetite is vigorous, the digestion and absorption rate is strong, the energy conversion rate for feed is also high, weight gain is rapid, and this is manifested in a lowered feed conversion ratio.

At present, the feed commonly used in aquaculture production falls into two major categories, natural and artificial, that is, one type is raw grain feed, such as oilseed meals, bran and middlings, and planted grasses, etc.; the other type is artificial feed processed and formulated. The former still has a fairly large amount of use in vast seawater farming areas, especially in the farming production of conventional fish, where it is even more widespread. The latter, because it has the advantages of good growth results, a protective function for the water environment, a low feed conversion ratio, and obvious economic returns, is rapidly expanding in scope and amount of use in aquaculture.

Select feed types whose quality and specifications meet farming requirements

The feed sold on the market has 2 to 3 grades in total, with crude protein contents of around 47%, 44%, and 42% respectively. In terms of quality, some have production dates more than a year ago, and some were produced recently; some were just extracted and pressed, and some have become moldy. Such differences in quality will inevitably affect the fluctuation and change of the feed conversion ratio in use. Therefore, when purchasing or using, we should strictly control quality, and during storage pay attention to moisture-proofing and mold-proofing.

The main influence of natural feed on the growth of farmed subjects

Applying base fertilizer, topdressing at the right time, and cultivating corresponding natural palatable feed at different stages is still a major supplementary means of implementing modern farming and lowering the feed conversion ratio. This is particularly important in the farming of special aquatic products such as shrimp and crabs, and in the fry cultivation stage of fish. In shrimp and crab farming, the fry that have just entered the grow-out stage are mostly tender and tiny, and at this time rotifers, cladocerans, copepods, and small benthic organisms among the natural plankton are their excellent food. They are not only comprehensive in nutrition but also easy to feed on, and are extremely beneficial to the growth of shrimp fry and crab fry. Therefore, cultivating these natural feed organisms is a very important and very urgent measure. Production practice has proven that generally during the growth period of shrimp and crabs, if sufficient natural feed can be obtained, more than 1/3 of artificial feed can be saved. In shrimp farming water surfaces with good natural feed, the feed conversion ratio of the shrimp artificial feed used can be lowered to below 1.0, becoming a major means of obtaining excellent economic returns.

So, have you learned it?

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This article is original by Sina Kandian (Weibo nickname), hereby declared