Animal Biotechnology

I.	Biotechnology

	Biotechnology:  The use of living organisms to improve, modify, 
			or produce industrially important products 
			or processes.

	Examples of Animal Biotechnology

	1.	Assisted Reproduction Techniques (ART)
		A.	Artificial Insemination
		B.	Estrus Synchronization
		C.	Superovulation
		D.	Embryo Transfer
		E.	In Vitro Fertilization
		F.	Sperm & Embryo Sexing
		G.	Embryo Splitting
		H.	Transgenic Animals

	2.	Genetic Engineering
		A.	Production of Animal Pharmaceuticals
		B.	Transgenic Animals
		C.	Gene Mapping of Production-related traits
		D.	Genetic Engineering of Animal Feedstuffs

	3.	Bioconversion of Animal Wastes

	4.	Vaccine Production

II.	Genetic Engineering

	Genetic Engineering:  The technique of removing, modifying, 
				or adding genes to a DNA molecule.

	Applications of Genetic Engineering:

	1.	Genetic components (whole genes or parts of genes) can 
		be reconstructed into unique combinations not easily 
		achieved by natural selection, or synthetic genes can be 
		constructed--Recombinant DNA.

	2.	Recombinant DNA can be introduced or reintroduced 
		into bacteria, plants, or animals.

	3.	If an organism integrates recombinant DNA into their 
		genome or genetic make-up, they are transgenic.

III. 	Production of Animal Pharmaceuticals--bST story

	1.	bST is produced in bacteria via genetic engineering

	2.	In dairy cattle, bST increases feed consumption and milk 
		production, by directing additional feed to milk production 
		rather than body maintenance.
		--Given after pregnancy in later lactation to maintain 
			higher milk production longer

	3.	pST may have benefits in swine industry.

			Research has found that pST:

			a.	Decreases time to market weight
			b.	Improves feed efficiency
			c.	Decreases carcass fat production
			d.	Increase litter size

	4.	Much public concern about human safety

			bST is safe!!!!!

III.	Transgenic Animals

	Transgenic Animal:  An animal whose genetic composition has been 
				altered to include selected genes from 
				other animals or species by methods other 
				than those used in traditional breeding.

		1st Transgenic Mice (1981)
		1st Transgenic Livestock (Sheep, 1985)

		Applications of Transgenic Livestock
	
		1.	Improved Production Traits
			A.	Somatotropin/Growth Hormone
			B.	Stimulation of muscle development 
				--c-SKI gene
			C.	Wool Production
				--Improve Cysteine Utilization
		2.	Improve Animal Health
			A.	Incorporate disease resistance genes	
			B.	Preformed antibodies
			C.	Interferon
		3.	Transgenic Milk
			A.	Why Milk?
				a.	Milk is readily collected 
					and available in 							large quantities.
				b.	Protein composition is simple 
					and specific
					--Caseins
					--Whey Proteins
				c.	Mammary gland can carry out 
					post-translational modifications 
					that microbial systems cannot.
			B.	Dairy Pharming: Production of medically 
						important products in milk.
				a.	Blood Factors
				b.	Peptide Hormones and Growth Factors
				c.	Enzymes
			C.	Manipulation of components already in milk
				a.	Simulate human breast milk 
					(Natural Formula)
				b.	Remove Lactose (Lactose Intolerance)
				c.	Alter casein for cheese production
		4.	Human organ transplant
			A.	Incorporate human genes into pig organs to 
				use as transplants
				a.	Pig organs similar in size to humans
				b.	Incorporated human genes would lower
					rejection.
				c.	Top candidates: Heart, Liver, Lungs


		Technical problems with producing transgenic livestock

		1.	Very low efficiency--<1%
		2.	Opaque Ova
			a.	Can't see pronuclei
			b.	Centrifugation helps, but causes trauma 
				to egg.
		3.	Long Generation Time
		4.	Most farm species can only carry two zygotes 
			to term.

IV.	Identification of Production-linked Genes 

	1. 	Uses Restriction Site Mapping and RFLP (and related technologies)
	2. 	Used in Breeding or as a Diagnostic
	3.	Examples:
		A. 	Milk Production gene in Dairy Cattle
			--PRL (Prolactin)
		B. 	Stress gene in pigs (PSS)
			--RYR1 (Ryanodine Receptor)
		C. 	Fertility gene in pigs
			--ER (Estrogen Receptor)
		D. 	Muscling gene in Meat Animals
			--c-SKI (Proto-oncogene)
	4. Hot area in animal breeding and genetics

V. 	Sperm and Embryo Sexing

	1. 	Production Applications
		A. 	Dairy and Egg production require more females
		B. 	Meat production prefer males
	2. 	Flow Cytometry
		A.	Most successful methods for sperm sexing in animals
		B.	Separates sperm by density 
			(Y sperm have slightly less DNA)
	3. 	PCR amplification of sex-specific genes now possible for
		 sexing embryos
		A.	PCR = Polymerase Chain Reaction
			a.	Amplifies DNA
			b.	Specific sex-related genes
		
VII. 	Using Biotechnology to Handle Animal Wastes

	1. 	Major Environmental Concerns

	2. 	Goal:  Bioconversion of manure into a more manageable waste 
			or useful byproduct.
	3. 	Methods?:
		A. 	Microorganisms
		B.	Plants
		C. 	Animals

VIII. 	Genetic Engineering of Animal Feedstuffs

	1. 	Plant Molecular Biotechnology
		A. 	Transgenics
		B. 	Gene Mapping of Plants for Breeding
	2. 	Example: Phytoestrogens
		a. 	Found in Legumes (Forages & Soybeans)
		b. 	Effect Reproduction
			--Negative (Cervix)
			--Positive (Increase Ovulation?)
		d. 	Other positive effects (humans)
			--Anti-cancer
			--Lower cholesterol
			--Menopause

IX.	Nuclear Transfer--"Cloning"

        1.	Cell nucleus from another donor put into
 		enucleated recipient
         	A.      Resulting offspring is a clone 
				of the donor
            	B.      Until "Dolly" all donors were
 			embryonic in origin

        2.  	Frogs done in early 70s

        3.	Mammals
             	A.      Mice (Early 80s)
            	B.      Cattle (Mid 80s)
             	C.      Sheep (Late 80s)
		D.	Monkeys and Pigs (90s)

        4.      Applications
                A.      Propagation of genetically superior 				lines
                B.      New way to make transgenics
                C.      Studies of imprinting and aging

	5.	Problems
		A.	Abnormal Placenta, Large Birthweight
        	B.	Ethical Considerations????
                	--Are humans next