histology reu finalppt 08042011

8/3/2019 Histology REU FinalPPT 08042011

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Developing and Testing an Approach for

Assessing Histological Sections of the

Pyloric Stomach in Mature and KeltSteelhead Trout

Veatasha H. Dorsey

CRISSP REU 2011

Fisheries

Prepared for the CRISSP REU SymposiumAugust 4, 2011


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OutlineSteelhead Background

1. Morphology

2. Life Cycle

3. Life History Theory

Problem

1. Spawning

2. FeedingObjectives

1. General/Specific

Methodology

1. Fish Collection

2. Histology Preparation3. Measuring

Results

Discussion

Furthering Research

Acknowledgements


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MATURE MALE

MATURE FEMALE


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MALE KELT

FEMALE KELT


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Pacific SalmonLife Cycle

Deposit eggs in grave nests and die


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Deposit eggs in grave nests and die

Pacific SalmonLife Cycle


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Life History Theory of Salmonid Species

Semelparity(Pacific Salmon)

Iteroparity(Steelhead)

Emphasis Juvenile survival Adult survival

Investment in

Spawning

High Lower


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Problem

Spawning

Iteroparity Rates

< 2% in

Snake/Columbia River

Historical rates-

unknown

Physiological Changes?


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Problem (con).Steelhead and Feeding

Mature spawners

Stop feeding during final

sexual maturation

If food is found in stomach;

eating out of habit

Kelts

Feed, rebuilding strengthto migrate toward the

ocean


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Credit: Zach Penney


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Project Objectives

General

Understand the changes in tissue microstructure of thepyloric stomach in two reproductive phases of steelhead(mature and kelt)

Specific

1. Characterizehistological profiles by identifying pertinent

tissue attributes2. Developa method to evaluate tissue architecture in pre-and post reproductive steelhead

3. Testthe method and display preliminary results


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Why Histology?

Insight on tissue level

organization

Disease detection andprevention

Static representation of

health


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Hypothesis

The length of theepithelial folds

and the area of

the rugae is

related to thesteelheads

ability to feed,

digest and

assimilate.


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Methodology (Fish Collection)

Dworshak (Sexually Mature)

Not feeding

Controlled environment

Steelhead representing sexually mature phase of

the adult spawning migration

Lower Granite Dam (Kelts)

Rebuilding energy stores

Steelhead in their post-spawning migration back

to the Pacific Ocean


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Dworshak


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Methodology (Histology Prep)

1. Tissue fixed in formalin

2. Sectioned for shipment(Colorado Histo-Prep in

Fort Collins, CO.)

3. Hematoxylin and eosin was

used for staining of paraffinembedded tissues


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Methodology (Measuring)

Measurements (MicroscopeSoftware-Calibrated m)

Area of Rugae

Three measurements per

fish

Total data points = 18

Length

3 ruga per fish

8 epithelial folds per ruga

Length and width

measurements

Total data points = 144


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1. Measure the base of the ruga

(dotted line).

2. Find the midpoint of the line.

3. Calculate length.

4. Calculate the width of the line

horizontally.

Measuring Area of

Ruga


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4. Label the quadrants

counterclockwise

5. Locate two suitable folds

6. Locate the longest and

shortest (max/min) in each

quadrant to measure.

Establishing

Quadrants


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7. Measure the cross sectional

area (l x w=a)

The optimum magnification:

100-300.

Measuring

Epithelial Folds

Length of Epithelial Folds: Mature vs Kelt


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Length of Epithelial Folds: Mature vs. Kelt

Phase of Reproduction

Mature Kelt

LengthofEpithelial

Folds(microns

)

0

5

10

15

20

25

30

35

40

Length of Epithelial Folds: Mature vs Kelt (By Sample)


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Length of Epithelial Folds: Mature vs. Kelt (By Sample)


Mature A Mature B Mature C Kelt A Kelt B Kelt C

Leng

thofEpithelial

Folds(microns

)

0

5

10

15

20

25

30

35

40

Area of Rugae: Mature vs Kelt


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Area of Rugae: Mature vs. Kelt


MATURE A KELT A

AreaofRugae

(microns)

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

22000


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Discussion

Average epithelial fold length in kelts ~ 50% longer than in

mature spawners

Average rugae area in kelts ~ 55% larger than mature

spawners Variation within kelts

Migration Distance

Spawn Timing Homogeneity within mature spawn

Holding tank


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Furthering Research

Quantitative histological

assessments of entire GI tract

Basically, Get to work Zach!!!!


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Ethical Implications

Endangered Species and

Reconditioning

Lethal Sampling

Understanding ofIteroparity

Tribal Significance


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Acknowledgements

Christine Moffitt, Professor-Fisheries

Zachary Penney, PhD Candidate-Fisheries

Ann Norton

Moffitt Lab

CRISSP REU Program

National Science Foundation (NSF)


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Questions?

Suggestions?

Be nice plueeaazzeee!!

K thanks!!!

histology reu finalppt 08042011

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