Topic 7 - Reproductive technology & immunology Flashcards
Define animal propagation…
selection & mating -> very successful
various ways to aid process or aid results
Pros of artificial insemination (AI)…
- Allows genetically desirable animals to be bred more efficiently (Natural mating = 1 bull services few females)
- diluted semen sample from 1 bull -> 500-1000 heifers!
- used in beef/dairy 40 years; some use in sheep; in horse (but not racehorse)
AI semen collection…
- Collected from sires via electroejaculation, dummy or real female
- Can be diluted (extender) with egg yolk
- Frozen in liquid nitrogen or used fresh
AI uses…
- extending coverage of individual males
- human repro.
- improving genetic diversity in zoo pop’s
- animal conservation in many endangered species
2 types of animal cloning…
Embryo splitting (ES) Nuclear transfer (NT)
Describe method of embryo splitting (ES)… (draw diagram)
- collect eggs & fertilise with sperm in petri dish (IVF)
- culture embryo to 8-16 cells
- using microscope, separate cells
- incubate each separately to early embryo stage
- implant into surrogate mothers
Uses of ES…
- 2 or more superior animals
- transgenic mice experiments (1 transgenic, 1 control)
- extended to humans (may cause defective embryos) to assist with IVF when mother cannot produce enough eggs after superovulation
- clone monkeys
Cons of ES?
- unknown genetic worth (may not pass ‘good’ genes to offspring)
- may cause defective embryos in humans
Describe nuclear transfer…
Replacing the nucleus of an egg cell (haploid) with a diploid cell to produce a viable embryo -> genetically identical individual of the donor nucleus
- can increase offspring from an animal 100’s to 1000’s
1st successful cloning done by…? Animal? Year? Results?
nuclear transplantation in Leopard frogs in 1950’s
Results: Blastula best (nuclei totipotent)
Commercial aspects of animal cloning… (include problems)
Only useful if traits are known e.g. superior milk yield, Melb cup winner, transgenic animals
Probs: genetic merit of organism cannot be established until adult; difficult, expensive
The Dolly clone… everything! Sheep used, process, diagram, break thru etc. Use diagram for help!
Finn Dorset sheep
- used nucleus from differentiated (somatic) mammary epithelial cell of 6 yo ewe
Process: Differentiated cells cultured in vitro & starved of nutrients -> G0 phase (non-dividing state) -> enucleated egg cells from Scottish Blackface breed -> nuclei transferred by mixing eggs & mammary cells via electrofusion -> embryos cultured & implanted into ewes prepared with hormone treatments
Dolly born 1996 - 2003
Break thru: dolly was 1st cloned from differentiated nuclei
Uses: study environment on isogenic animals; multiplication of superior livestock
First successful sheep cloning experiment via NT…?
1986, sheep eggs collected & enucleated via UV radiation -> each egg fused with cell from 16-32 cell embryo in petri-dish -> embryos cultured & implanted into surrogate ewes -> 32 cell embryo => 32 clones
What process is important to ensure genetic diversity?
reproductive techniques in conservation biology via storage of (eggs & fertilised embryos) germplasm & frozen sperm banks
What is MOET? Animals used in…
Multiple ovulation & embryo transfer
- Cattle industry
- superovulate heifers with hormone treatments -> AI laproscopically with bull semen -> flush fertilised eggs & freeze in liquid nitrogen -> implant in surrogates
- used in zoos to make embryos mobile
Name the 3 types of natural immunity…
- Body surface
- Non-specific responses
- Immune responses
Name some body surface barriers…
skin
mucuous membranes
tears & saliva (lysosome)
What is meant by non-specific responses?
inflammation
WBC - neutrophils, macrophages, eosinophils, basophils
complement - blood clotting
What are cytokines? Give examples… (remember viral figure)
antimicrobial agents
eg. Interferons, interleukins, lactoferrins, transferrins…
What are interferons? (draw viral figure)
carbohydrate (peptide glycoprotein) molecules cytokines) important in viral infections produced by cells infected with virus
What are interleukins? Properties…
cytokines that are produced by cells that attract phagocytic cells, induce inflammatory response, stimulate Ab prod. by B cells (plasma cells), and TNF
There are several…
Lactoferrins, transferrins…
Iron binding proteins - bacteria require iron for growth
lactoferrin in milk, saliva, tears
transferrin in blood
What is the complement system? What are the different ‘complement systems’? Remember diagram
30 different proteins in the blood that have multiple effects
- opsonisation - increase phagocytosis by coating pathogen
- inflammation - histamine -> increase blood vessel permeability and attracts phagocytes
- cytolysis - pores in microbial plasma membrane -> inflow of extracellular fluid -> burst of microbe
Phagocytic cells…
cells engulf bacteria, viruses… & digest them
contain hydrolytic enzymes (lysozymes, lipase…)
WBC - leukocytes & monocytes
