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Biotech in Animal Reproduction

Biotech in Animal Reproduction. Terms. Artificial Insemination The deposition of spermatozoa in the female by artificial means Sperm The male sex cell, produced by the testes Semen

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Biotech in Animal Reproduction

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  1. Biotech in Animal Reproduction

  2. Terms • Artificial Insemination • The deposition of spermatozoa in the female by artificial means • Sperm • The male sex cell, produced by the testes • Semen • A fluid substance produced by the male reproductive system containing spermatozoa suspended in secretions of the accessory glands

  3. Terms • Sire • The male parent • Quarantine • Process that requires animals to be kept in isolation for a period of time to make sure they do not have a disease • Protectant • Substance such as glycerin added to semen before it is frozen

  4. Terms • Estrus • The period that a female animal is ready for mating • Artificial Vagina • A rigid tube used to collect semen for artificial insemination • Ejaculation • The discharge of semen from the reproductive tract of the male

  5. Terms • Conception • The beginning of gestation; when a sperm fertilized an ovum • Motility • Active movement in artificial insemination of the sperm • Extender • A substance, such a milk, egg yolk, glycerin, or/or antibiotics, that is added to semen to dilute and protect it

  6. Terms • Straw • Small hollow tubes that contain frozen semen • Hormone • A chemical substance produced by the body or introduced into the body to produce a specific effect • Estrus Cycle • The reproductive cycle in nonprimates

  7. Terms • Follicle Stimulating Hormone (FSH) • A hormone to induce estrus • Follicle • A small blisterlike development on the surface of the ovary that contains the developing ovum • Embryo Transfer • The process of removing an embryo from a superior female and implanting it into an inferior female.

  8. Terms • Dam • The female parent • Progeny Testing • Test of the value of an individual's genotype by looking at the progeny produced by different matings • Donor Cow • A cow that is of unusual value as a breeding animal, used for embryos

  9. Terms • Recipient Cow • A cow of ordinary value that will be implanted with a superior female’s embryo • Superovulation • Process of injecting the donor animal with a follicle stimulating hormone which will cause the animal to release several eggs instead of just one • Prostaglandins • Hormones that will make a recipient cow come into estrus

  10. Terms • Corpus Luteum • Active tissue that produces progesterone if conception occurs (Yellow Body) • Sperm Sexing • Separating the female (X) cell from the male (Y) cell in order to produce only male or only female offspring • Cytometer Cell Sorter • An instrument used to sort (X) sperm from (Y) sperm according to the amount of light given off by the chromosome

  11. In this chapter: • Biotech in animal breeding • Advantages of artificial insemination • Process of artificial insemination • Semen processing, storage and shipment • Estrus synchronization • Egg production • Advantages of embryo transfer • Process of embryo transfer • Advantages of sexed semen • Sperm sorting An Overview Every aspect of the livestock industry is dependent on animal reproduction!!!!

  12. Artificial Insemination • Artificial Insemination • The deposition of spermatozoa in the female by artificial means • Sperm • The male sex cell, produced by the testicles • Semen • A fluid substance produced by the male reproductive system containing spermatozoa suspended in secretions of the accessory glands

  13. Advantages Use of the highest quality animal available Cost of semen vs whole animal Availability of records # of offspring (potential for 40,000+ from one male) Goals & selectability for herd needs Farm safety (No bull/aggressive male) Reduced transmission of disease (genetic & sexual) No quarantine time on out of country stock Reduced sire cost to producers Increased uniformity

  14. Sire • The male parent • Progeny Testing • Test of the value of an individual's genotype by looking at the progeny produced by different matings

  15. Development • As far back as the middle ages • Collection of prized enemy stallions • First successful insemination: 1780 • LazarroSpallanzani • Dog • Little economic value at the time • 1st large scale use • Russians 1900 • Horse repopulation • Cattle & Sheep 1920/30s

  16. How it works:

  17. Problems? • Preserving live sperm • 2-3 day life span • Freezing! • Relatively few sperm survived • ALL HAIL THE 1950s!! • Protectant: Substance such as glycerin added to semen before it is frozen • Temperature lowered at a specific rate until -320°F • Will remain viable for years (30+!)

  18. Any drawbacks? • Labor intensive! • Monitor for estrus • Singular restraint & insemination • Requires skilled technician • Subject to potential abuse? • Accentuate damage of poor sire? • Additional capital & management • Others?

  19. Dummy animal & artificial vagina • Sperm examination • Number (15,000,000+ = normal) • Motility • Shape • Add extenders Semen Collection & Processing Artificial Vagina A rigid tube used to collect semen for artificial insemination Extender A substance, such a milk, egg yolk, glycerin, and/or antibiotics, that is added to semen to dilute, nourish and protect it

  20. Volume of Semen and Conc. Per Insemination *1 cc is the volume of semen contained in each straw of bull and ram semen

  21. http://www.youtube.com/watch?v=y6IEk9RNvA4 • http://www.youtube.com/watch?v=lzJhhfyoxY0 • http://www.youtube.com/watch?v=qgf6h588v-I Semen Collection by Specie Bull Boar Turkey

  22. Examined and packaged in straws Stored at -320°F in liquid nitrogen Thawed immediately before placed in female • Proper temp & speed Straws:Small hollow tubes that contain frozen semen

  23. When to breed:

  24. Heat Detection • Visible activity: • Excitability, restlessness & noisy • Attempt to ride other cows • Stand to be ridden by other cows • But what if you’re not there? • Ruffled hair on tale head • High tail head appearance • Genital mucus • Swollen vulva • Tail chalk, kamars, heat detect systems *In Cattle

  25. Repro Cycle in Farm Animals

  26. Factors for Consideration Highest conception rates = 60-90 days after calving Breed from 9 hrs following heat to 24 hrs after heat Sperm will live about 24 hrs in the female repro tract True heat is when a cow will stand to be ridden Fertilization will occur immediately if sperm is present when the egg is released

  27. Think about It: Discuss how AI might be of economic importance to a livestock producer. What is the female hormone produced by the ovary that regulates the heat period? What is parturition? What is semen extender?

  28. Elimination of consistent monitoring • Big savings! • Time • Labor • Costs • Hormone regulation!! Control of the Estrus Cycle Estrus Cycle The reproductive cycle in non-primates

  29. Hormones!! • FSH • A hormone to induce estrus & stimulate ovum release • LH • Triggers ovulation • Progesterone • Produced by CL to maintain pregnancy • Prostaglandin • Hormones that will make a recipient cow come into estrus • Estrogen • Released by the follicle; signals heat

  30. In other words:

  31. FSH • Stimulates follicle • Begin cycle at injection • Synch groups of animals to ovulate at the same time • SAVES BIG! • Resources at breeding • Resources at calving/farrowing • Groups of same age animals

  32. Embryo Transfer http://www.youtube.com/watch?v=hRUJSMfFgfc

  33. Benefits of Embryo Transfer Advancement of genetics from the dam Progeny testing of females Import and export without quarantine Dual production system (milk & meat) Twinning Conversion from grade to registered/purebred

  34. Disadvantages Narrowed genetic base Loss of diversity Case and point: Guernsey cattle

  35. Selection of donor and recipient cows • Donor depends on: • Milking ability • Ability to grow • Reproductive capacity • Show appeal • Recipient depends on: • Health • Ability to maintain pregnancy • Ability to deliver a healthy calf Process of Embryo Transfer Donor A cow that is of unusual value as a breeding animal, used for embryos Recipient A cow of ordinary value that will be implanted with a superior female’s embryo

  36. Get them In Synch!

  37. Not like that! Donor Animals Recipient Animals • Superovulation • 12-15 eggs • Inject FSH • Several follicles to shelter growing eggs • Prostaglandin • Causes estrus • Insemination • Collection • Grown for ~1 week • Prostaglandin • Causes estrus • Monitor CL • Implant embryos • In uterus

  38. The Flush! And not like this either!!! Or this!!

  39. The REAL Flush! • Long rubber catheter • Passed through cervix to uterine horn • Inflatable bulb • Seals entrance to the uterus • Solution injection • Fill fallopian tubes and uterus • Drainage • Solution and eggs drain into collection cylinder • ~6 embryos per flush And afterwards? The uterus is flushed again with a solution that will kill any remaining embryos to prevent infection.

  40. The numbers • Up to 30 embryos could be obtained in one flush (usually 6-7) • Survival to term: 50-70% • Superovulatedvs non • Non= 5 calves/year Super= 9-12 calves/year • Recovery = 50-90%* • Cattle = 50-80% • Horses = 40-90% • *Nonsurgical methods

  41. Think About It What support technology & procedures are involved in ET? What are the advantages to embryo transfer? What are the expected result rates of ET? What is superovulation and why is it used? Indicate expected recovery rates concerned with ET? What is estrus synch?

  42. Sperm Sexing • Why? • Depends on industry • Dairy: Females = milk producers • Swine: Boar meat = odorous & unacceptable • Beef: Males = bull studs for breeding • Poultry: Females = layers

  43. Chromosomes A refresher: Females have 2 X chromosomes Males have an X and a Y When eggs are formed they all have an X Sex determined by which sperm fertilized the egg

  44. 1989: Method patented • Fluorescent dye adheres to sperm DNA • Female chromosome has more DNA • More dye in the female chromosome (by 2.8-7.5%)!! Sperm Sexing Sperm Sexing: Separating the female (X) cell from the male (Y) cell in order to produce only male or only female offspring Cytometer Cell Sorter: An instrument used to sort (X) sperm from (Y) sperm according to the amount of light given off by the chromosome

  45. And now? And now? Guarantee 85-95% accuracy (cattle)

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