Table 2.
Survival to hatching of shortnose sturgeon embryos under various container types and egg maintenance protocols
| Container |
Container parameters |
Survival to hatchinga |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. | Type | Dimensions (dia. × h, or L × W × H) |
Water vol. (ml) |
Bottom area (cm) |
Water depth (cm) |
Base conditionsb |
Low temp (15°C) |
High temp (20°C) |
Daily water change |
Air | Replace container |
No Fuller's earth |
| 1 | Modifiedc MacDonald's jars | 13.8 × 40 | 6,000 | 150 | 40.0 | 0.17 (0.000) | ||||||
| 2 | Nylon mesh-bottom cylinder (3.8-cm-diameter PVC) in pan | 5.3 × 6.5 | 4,000d | 22 | 2.0 | 0.50 (0.088) | ||||||
| 3 | Nylon mesh-bottom cylinder (7.6-cm-diameter PVC) in pan | 7.6 × 5.2 | 4,000d | 45 | 2.0 | 0.58 (0.102) | ||||||
| 4 | Glass beaker (250 ml) | 6.3 × 9.5 | 150 | 31 | 4.75 | 0.46 (0.117) | ||||||
| 5 | Glass beaker (100 ml) | 4.5 × 7 | 80 | 16 | 5.0 | 0.63 (0.088) | 0.09 (0.069) | 0.43 (0.173) | 0.37 (0.133) | 0.69 (0.096) | 0.59 (0.107) | 0.14 (0.164) |
| 6 | Glass dish | 15 × 11 × 4 | 250 | 171 | 1.5 | 0.62 (0.077) | 0.10 (0.067) | 0.33 (0.033) | 0.57 (0.058) | 0.04 (0.038) | ||
a
Entries are average (± SD) survival of three replicate groups per protocol except for the MacDonald's jar (n = 1).
b
Base conditions: 30 fertilized and de-adhesion eggs in 0.1 ppt salt water, twice daily water change, no aeration, 15°C, 14 h light per day.
c
MacDonald's jar base conditions: water recirculated through ultraviolet lamp and biofilter with 50% water replacement daily.
d
Volume is for water pan (38 × 30 × 9 cm) into which mesh baskets were placed.