For over a decade, we have been committed to formulating trophy bass feed for growing trophy largemouth bass in ponds.
We have conducted sampling throughout the United States, studying bass in relation to various food sources. Our research includes observations of their aging processes, their responses to stressful conditions, and their growth patterns. By utilizing existing research and conducting numerous trials, we have developed our own studies focused specifically on largemouth bass.
To begin with, much of the science behind fish food originates from aquaculture, which is the term for farming fish and has been in existence for centuries. The majority of aquaculture focuses on trout, salmon, tilapia, catfish, and shrimp. While there are other species cultivated, these five represent the vast majority of global aquaculture.
These global markets are substantial and continuously expanding. Almost all of the fish feeds in the pond and lake management marketplace are diets either directly sourced from the aquaculture industry and relabeled for pond species, or designed based on research conducted within the aquaculture industry. Although this wealth of information is incredibly valuable, some findings can become complicated when applied to largemouth bass.
For instance, salmon and trout thrive in cold water, tilapia are primarily herbivorous, catfish have a varied diet, and shrimp consume their feed very slowly. This information is not particularly useful when formulating diets for largemouth bass, especially when looking to understand the dietary needs of fish that live for five years or more.
Largemouth bass occupy a position in the trophic chain that is quite similar to that of trout. Although their environments differ significantly, the research around trout provides a starting point for understanding the nutrient requirements of largemouth bass. Many universities have conducted valuable research to identify the various nutritional needs of these fish in their labs through growth trials. Most growth trials focus on small fish because they grow quickly. During the early life stage growth trials, the fish are weighed at regular intervals, the data are plotted over time, and then compared to other replicates and treatments within the trial system.
While this information is extremely valuable, it is well known that the nutritional requirements of fish, like those of most other animals, change as they mature. Sourcing, handling, and feeding larger fish are much more challenging. As a result, much of the available data is skewed toward early life stages. In aquaculture, where fish are harvested once they reach a certain size, understanding the nutritional needs of older fish may be less critical, and this approach makes sense in that context, but leaves a gap in understanding the impact feed plays on fish raised for longevity.
Digestibility is a topic we discuss frequently. Various metrics are used to measure or evaluate the effectiveness of fish feed. One commonly used metric is the Feed Conversion Ratio (FCR), which indicates how much feed is required to grow a fish. For example, an FCR of 1 means that it takes about 1 pound of feed to produce 1 pound of fish. There are different types of FCRs and various equations to calculate them.
Elevated FCRs can result from many environmental factors. In a laboratory setting, we strive to control external factors as much as possible to ensure that the results accurately reflect the feed’s capabilities. However, in a pond environment, using FCRs becomes nearly impossible since fish have the opportunity to eat whatever they want, and the feed is merely supplemental. For instance, if a bass consumes a few pellets and then catches a bluegill, the FCR for that diet may appear impressive, but it would be quite misleading.
Each ingredient contains both digestible and indigestible components. Different fish species respond better to certain ingredients than others. Therefore, selecting the right ingredients is essential for formulating any effective diet.
Ingredient digestibility is typically assessed through digestibility trials, which follow a well-established protocol. More information about this process can be found on the USDA ARS website. In essence, a published reference diet is created, which is then mixed with 30% of the ingredient being tested. Each of these diets includes an inert marker in the formulation. The diets are then fed to a tank of fish. Fish are then gently sedated before being stripped of their feces. This fecal matter is collected and freeze-dried. Once enough samples are obtained, analyses are conducted on both the diets and the corresponding feces. This enables the evaluation of the ingredient’s digestibility as well as the overall accuracy of the experiment.
One challenge with largemouth bass is that most of the existing digestibility data is based on salmonids raised in cold water.
Additionally, modern feeds are produced through extrusion, which has been shown to enhance the overall digestibility of ingredients. Many of the diets used to build this database were made using modified meat presses, which did not allow for heat or preconditioning. As a result, factors such as pellet stability, density, and overall cooking parameters were not tightly controlled.
While the database serves as a useful starting point, it does present challenges when formulating high-performance feeds for largemouth bass.
Ten years ago, we embarked on a journey to discover how to grow trophy bass. To this day, we believe that the best way to achieve this is through a strong focus on trophy forage, with bluegill being our flagship species. By creating a diet that optimizes the health and reproduction of bluegill, we ensure that the nutrition packed into our pellets reaches the bass without needing to entice them to eat the pellets directly. After all, bluegill are far more exciting for a bass to chase than pellets!
After conducting a sampling tour, we spent considerable time examining fish livers. The ratio of liver size to fish size is known as the hepatosomatic index, which is part of a larger set of organosomatic indices commonly used in aquaculture. Many people discuss “fatty livers” or “pale livers,” but we were uncertain about the implications of these conditions and what levels could be considered good or bad.
We sampled fish that were on our diets, fish on competitor diets, and fish that had only consumed forage. We observed distinct differences in the results. Livers from fish fed diets with supplemental feed showed more vacuolization (spaces) compared to those from forage-fed fish. Although we could see varying levels of vacuolization, there was not an indication as to what level the vacuolization became an issue.
With this new information, we proceeded to the next round of sampling, focusing on analyzing liver glycogen and lipid levels. The liver serves as a storage site for excess nutrients in fish. This led us to ask whether the fish were storing fats from the diets or if the carbohydrates (along with their sources) in the diets were responsible for this storage. Based on our findings, we then formulated a bass diet that had high protein levels and low fat levels.
Creating a high-protein, low-fat diet can be quite challenging. Nearly all quality protein sources contain some fat as well. Typically, when the protein level increases, the fat content rises too. Fortunately, we have a long history of working with innovative ingredient companies, and we have access to some unique new products that enable us to formulate high-protein, low-fat diets effectively. Additionally, this diet needed to have special attention paid to the type of carbohydrates used. To make extruded pellets float, starch is necessary. Feeding pond fish with sinking diets can be difficult to observe, and the standard preference is to see a floating pellet, so we needed to ensure that the pellets float, regardless of the fish’s preferences. With the final formulation of all the right ingredients, we had begun the journey of developing the correct feed for largemouth bass in a pond environment.
Just like humans, as fish age, their growth rate slows down. Extra energy is no longer utilized for rapid growth but is instead stored as fat. Fish tend to eat based on their energy requirements rather than their protein needs. Therefore, a high-fat diet may lead a fish to stop eating before it consumes enough protein for optimal growth. In ponds with older fish and larger fish sizes, a higher protein and lower fat diet is highly beneficial.
While we were pleased with the success of the new diets, there was still something that concerned us.
A young bass needs more energy, and largemouth bass have…well…large mouths. This means that a remarkably young bass could potentially consume our larger “adult bass” pellets.
Then came another breakthrough for us regarding trophy bass pond feed while making largemouth bass feed for the aquaculture industry.
As many know, we have additional products specifically sold into the aquaculture space. Feeds are designed to grow fish fast with low FCRs and low impact on water quality, so producers can get more fish to market with low operation costs.
We produce a significant amount of largemouth bass feed for aquaculture, which is an exciting area for us. We have conducted a lot of research around ingredient digestibility and formulation optimization for largemouth bass intended for food markets. It is well known that largemouth bass do not efficiently utilize carbohydrates; most of their energy comes from lipids and proteins. Our research indicates that the optimal levels for crude protein and crude lipids in aquaculture bass diets are around 48% protein and 18% fat.
To meet the essential fatty acid requirements and the total energy needs of Largemouth Bass, we use a combination of fats in our diets. One day, we made an error by placing the oils incorrectly and flipped the ratio, which led to enlarged livers in our trial fish. This was the first time we had witnessed something inducing the “fatty liver” phenomenon. Many fish have the ability for “de novo synthesis,” which essentially refers to the production of substances from simple molecules through complex processes. Some fish use a novo lipid synthesis process that converts excess carbohydrates into fatty acids. Additionally, there are complex metabolic processes which transform certain fats into other fats as well.
The importance of maintaining the right balance of fatty acids in the lipid component of a diet cannot be overstated. After over a decade of experience, our formulations have culminated in what we believe to be the best pond Largemouth Bass diet we have ever created, our Performance Bass Blend 8mm and Performance Bass Blend 22mm.