Description

The MazeEngineers Zebrafish larvae T Maze takes advantage of a unique backlighting to allow for fine behavior tasks in larvae. Similar to the Drosophila mazes, this apparatus comes with a start lane, bidirectional swimming pools, and a unique backlight for easy video tracking. An easy to use cover seals the pools and watertight chambers ensures that you’ll be able to use this apparatus for years to come. The apparatus comes with:

  • Lid
  • Chambers
  • Backlight

Special Requests can include

  • IR Backlight. Please inquire for more details
  • Modifications in size up to 50% for older stage larvae

Price & Dimensions

Larvae T Maze

$ 1390

  • Start Arm Length: 50mm (A/B).
  • Arm corridors: 25mm, width 5mm, depth 10mm, intersection 25mm2.
  • Pool size: E/F: 1950mm2 pools

Frequently Asked Questions

  • Can I change the size of the apparatus?
    • Yes! We can modify the apparatus as need be
  • What color backlights do you provide?
    • We provide a fluorescent backlight that is included in the order. If you need special bulbs such as IR, there will be a small revision to the quote but it will not be significant (approx $100)
  • Is the chamber watertight?
    • Yes!

Request a Larvae T Maze

Request a Larvae T Maze

Documentation

Introduction

Spontaneous alternation behavior (SAB) is conveniently assessed by the T-maze in adult zebrafish to observe the mnestic tendency that enables them to make alternate choices. However, the novel zebrafish larvae T-maze evaluated SAB for the very first time in larval Zebrafish (Bogli, 2016).The larval T-maze apparatus is also used to explain the exploration pattern followed by Zebrafish larvae for food and shelter. Among these primitive existence needs, non-associative forms of learning such as habituation and sensitization have been successfully presented by larval zebrafish (Best et al., 2008).

The Zebrafish Larval T-Maze apparatus majorly consists of two starting arms and two goal arms. Each goal arm is accompanied with a separate swimming pool. Equipped with a unique backlighting feature to assist video tracking of fine behavior and locomotive skills in larvae.

Spontaneous alternation behavior tests are a combination of examining consecutive choices (Lalonde, 2002), forced turn trials (Dember and Richman, 2012), stimulus satiation, and action decrement (Dember and Fowler, 1958; Hughes, 2004).

The spontaneous alternation behavior test is conducted by placing the larvae at the starting arm of the larval T-maze to determine their natural choice of a path towards the goal arm. It is repeatedly examined to observe the change in consecutive choices. Furthermore, the learning is reinforced by the generation of an external sensory stimulus in the apparatus. Since larval T-Maze flexibly allows the opening and closing of different arms; SAB tests can be employed for a wide array of memory studies by promoting and enforcing decision-making in Zebrafish larvae.

Apparatus and Equipment

The larval T-Maze apparatus comprises of four arms and two pools. Both the start and the main arms are 50 mm in length, while both the goals arms are 25mm in length. These corridor lengths significantly allow the Zebrafish larvae to display their exploration and learning behavior.

All the corridors are 5 mm wide with a depth of 10 mm. The interlocking intersections are of 25 mm². Each goal arm leads to a separate pool which is of 1950 mm².

The larval T-maze apparatus is equipped with a fluorescent backlight, with a facility of replacing it with special bulbs like IR. In addition to the illumination, the apparatus can be heated from below. Both of these factors facilitate in observing the fine behavioral patterns of the larvae. Not only this, the light and heat can also be utilized in the re-enforcement stimuli experiments.

The entire chamber is watertight and comes with an easy-to-use cover that can seal the pools.

Training Protocol

Pre-Training for Zebrafish Larvae T-Maze

Before the start of the experiment, the larval T-maze is pre-filled with an E3 medium which is carefully brought to larvae favorable temperature of 28°C.  The experimental subject is transferred to the starting arm of the apparatus 10 minutes prior to the experiment while keeping the intersection between the starting and the main arm closed using a translucent tube. The ideal sample size is 20 larvae per trial; however, the apparatus size is customizable if there’s a need to handle a larger sample.

After 10 minutes of adaptation period, the tube is removed to open up the apparatus’s corridor between the starting and the main arms. It allows the larvae to explore the path towards the goal arm. The main objective of the test is to quantify the latency in entering the goal arms and the number of larvae making successful entries within the first 10 minutes of the trial.

The time is recorded using a stopwatch containing two buttons; one records the number of larvae entering the goal arm and the other records the time taken by each larva to reach the goal. In case any larva returns to the main arm or enters the second goal arm after a prior successful goal arm entry, only the first entry will be counted.

For automated tracking, Noldus EthoVision XT can be used for the recording of larvae movement and activity. Since this high-tech automatic video tracking system possesses the facility to measure the elongation and mobility of the larvae, it can efficiently track and record the number of larvae entering the goal arm. This recording is also valuable is revalidation and reconfirming of the facts and test results in the future.

The total time taken for the test is 20 minutes (including the 10 minutes adaptation time in the apparatus). Once the test is complete, the larvae and E3 medium should be removed from the larval T-Maze. The apparatus should be disinfected before the commencement of another experiment.

Evaluation of Spontaneous Alternation Behavior

Larval T-Maze apparatus can be used to evaluate the spontaneous alternation behavior in Zebrafish larvae. The number of consecutive turn directions contributes to the SAB score.

Evaluation of Forced Turn Trials

The larval T-Maze apparatus is also effective in conducting the forced turn trials on Zebrafish larvae. The arms can be conveniently closed to force the subjects to move towards the desired corridor.

Evaluation of Cognitive Functions

SAB experiments using larval T-Maze apparatus are essential in observing the early cognitive functions like memory and learning in Zebrafish larvae. This learning is imperative to develop the navigational skills that are essential for survival.

Sample Data

This sample data represents the Spontaneous Alternation Behavior observed using the larval T-Maze apparatus which allowed the consecutive turn-directions.

The relationship between total numbers of Larvae tested vs. the number of Larvae making a successful entry in one of the Goal arms.

It is evident from the above data that most of the Zebrafish larvae made a successful entry in one of the goal arms within the first 10 minutes of the trial. Additionally, most of the larvae that made a goal arm entry displayed SAB.

Strengths & Limitations

Strengths

Strengths

Zebrafish Larval T-Maze apparatus provides an unprecedented facility to observe the mnestic capabilities possessed by Zebrafish during the early developmental stages. The larval T-maze apparatus is also used to observe and elucidate the search pattern pursued by Zebrafish larvae for food and shelter.

A remarkable benefit of backlighting in larval T-maze apparatus allows the tracking of fine behavior in Zebrafish larvae such as Spontaneous Alternation Behavior (SAB), as well as the close study of locomotive skills in this species.

This novel apparatus promises a highly practical utility for a wide range of experiments to probe mnestic studies on different developmental stages of Zebrafish larvae.

Limitations

The manual recording of time is prone to errors. However, this limitation can be eliminated by using an automatic video tracking system such as Noldus EthoVision XT, which provides a flawless method to track and record the animal’s movement.

Summary and Key Points

  • Spontaneous alternation behavior test is widely used for mnestic studies.
  • Larval T-Maze apparatus comprises of two starting arms and two goal arms; with each goal arm accompanying a separate swimming pool.
  • It can also be used to evaluate memory development in Zebrafish larvae by promoting and enforcing decision making.
  • Zebrafish models are extensively used in biomedical research fields including addiction, toxicology, aging and neurological disease.
  • The apparatus is watertight with a fluorescent backlight.

References

Best, J. D., Berghmans, S., Hunt, J. J., Clarke, S. C., Fleming, A., Goldsmith, P. and Roach, A. G. (2008). Non-associative learning in larval zebrafish. Neuropsychopharmacology 33, 1206-1215.

Stefan Yu Bögli, Melody Ying-Yu Huang. (2016). Spontaneous alternation behavior in larval zebrafish. Journal of Experimental Biology; 220: 171-173. Doi: 10.1242/jeb.149336

Dember, W. N. and Richman, C. L. (2012). Spontaneous alternation behavior: Springer Science & Business Media.

Dember, W. N. and Fowler, H. (1958). Spontaneous alternation behavior: Psychological Bulletin 55, 412.

Lalonde, R. (2002). The neurobiological basis of spontaneous alternation: Neuroscience & Biobehavioral Reviews 26, 91-104.