3.4. Field dissection of the spermatheca
When learning the procedure of insemination, it is helpful to check the spermatheca to determine the degree of insemination success. Sperm migration requires about 40 hours post insemination. After insemination, a subset of queens can be held in a nursery colony until tested.
Procedure for field dissection of spermatheca:
- Sacrifice the queen, by crushing her head and thorax.
- Grasp the queen’s terminal abdominal segments, dorsally and ventrally.
- Pull and separate the terminal segments from the rest
of the queen’s body, with your fingernails or forceps (Fig. 20).
a. The spermatheca is a white, spherical structure about 1 mm in diameter, and appears rough in texture due to the trachea net covering (Fig. 21).
- Tease the spermatheca out of the body cavity with your thumbnail or forceps.
- To remove the tracheal net, gently roll the spermatheca between your
fingers. The net will collapse in a small white mass.
a. The colour shade and density of the spermatheca indicates the relative insemination success of the queen.
b. The spermatheca of a virgin queen is clear (Fig. 22).
c. A cloudy or milky appearance of the spermatheca indicates an inadequate insemination or a failing queen (Fig. 23).
d. For a fully inseminated queen, the spermatheca is a creamy tan colour with a pattern of marbled swirls (Fig. 21).
Fig. 20. Exposing the spermatheca. To expose the spermatheca, grasp the queen’s terminal abdominal segments, dorsally and ventrally and pull to separate these segments from the rest of the queen’s body, with your fingernails.
Fig. 21. The spermatheca is a white, spherical structure about 1 mm in diameter and appears rough in texture due to the trachea net covering.
Fig. 22. Comparison of spermathecas of a virgin queen (clear) and mated queen (tan with a pattern of marbled swirls).
Fig. 23. The spermatheca of a failing or poorly mated queen is a milky colour.