Chapter 3

Fertility Control

 

3.1  POINTS TO PONDER:

There are 48M Dogs and 35M Cats in USA - 90% of Dogs and Cats are homeless - Approximately 200,000 Dogs yearly are used in Research - Approximately 55,000 cats yearly are used in Research - An estimated 1 3M dogs and cats are euthanized yearly in U.S. animal shelters. 

3.2 WHY - SUCH AN EXPLOSION IN POPULATION? 

Demographic study of California cites:

A. Overproduction:

In early 1960's - increased demand

1961 - approx. 40,000 pups entered Homes

1967 - approx. 73,000 pups -entered I Jomes

1968 - approx. 71,000 pups entered Homes

sudden drop in 1969 - approx. 57,000 pups entered Homes

demand>Supply 1970 - approx. 43, 000 pups entered Homes

  • - pups adopted in Fy 67-69 Etc. were also in reproductive age; hence increased supply.

B. Economy:

  • -1 970 - on world recession set in. So owners could not keep pets. 1970-1971,12.4% decrease in owners reclaiming of their pets.
  • - increased life expectancy of animals to approx.8.5. yrs - In post puberty population survery's females predominated over males - maximum reproductivity centered around 1 to 3 yrs old females. - Annual liter production per intact bitch and queen was 0.2 litter and 0.9 respectively.
  • - An increase of only 0.1 liter/intact bitch (0.2-0.3) per year would result in 50% more puppies.
  • - Neutered % in two California Counties:

-

1970

1975

Female dog

48%

52%

Male dogs

7%

10%

Female cats

65%

74%

Malecats

52%

57%

Even with 74% cats neutered still there was 10% excess kittens than in 1970. So explosion in pet population is due to over supply, depressed/static economy, changing life styles increased pet life expectancy. 

3.3 IS IT A CAUSE TO WORRY? 

Unrestricted/Uncontrolled pets - prey on domestic and wild life - raid garbage, over tum trash - excreta strewn over streets, pavements and yards. - manifest law of the Jungle - increased zoonotic diseases. 

3.4 WHAT IS NEEDED?

Responsible pet ownership through education and control of pet population through contraception and other such means.

 3.5 CONTRACEPTION 

Voluntary prevention of conception or impregnation 

3.6 CLASSIFICATION OF METHODS AVAILABLE 

3.6.1a SURGICAL:

Female <-- ovarihistorectomy, Tubal ligation, Salpingectomy hysterectomy, ovariohystorectomy

Male <-- Castration, Vasectomy

3.6.1b NON SURGICAL:

  • a) Mechanical: Intravaginal and intrauterine devices
  • b) Pharmacologic
  • c) Immunologic
  • d) Irradiation/Heat and Ultrasonic's

3.6.2a Precoaital:

Surgery, ovaban, Mibolerone etc. 

3.6.2.b Post Coaital:

Surgery, Estrogens, PgF2 alpha etc.

3.6.3.a Male Contraception:

Surgery, Sclerosing agents, Immunologic methods. 

3.6.3.b Female Contraception:

Surgery, ovaban, mobolerone, estrogen, PgF2 alpha etc. 

3.6.4 CLASSIFICATION OF FEMALE CONTRACEPTIVE 

3.6.4.1 Prevention of cycle or ovulation 

  • a- Surgical, ovariohystorectomy b- Surgical, therapy with P4 a Androgens EAQ Megestrol acetate Proestrus, Anestrus ,Combined. Rx.

    <-- Mibolerone 

    Depoinjection:

    Medroxyoprogesterone acetate (MPA) Progesterone 

    S/Q implants = Progesterone Testosterone c. Immunization: Anti LH, HCG

3.6.4.2 Prevention copulation:

isolation/intravaginal D

3.6.4.3 Prevention of Implantation:

  • a. Antinidatory Estrogen Treat EQ DES and Mestranol
  • Inject: Repositol. DES, ECP, EV, EB Estrone 

3.6.4.4 Termination of Pregnanacy:

  • Pg F2 alpha, DL-717-1, Steroids-DXM
  • Bromomergocryptine

3.6.4.5 Others: Pilocarpine, irradiation etc. 

3.7 SURGICAL CONTRACEPTION 

3.7.1 OVARIOHYSTERECTOMY:

Mostcommon.

Advantage eliminates estrus cycle and Assoc. attraction of male -Decreases incidence of Mammary T. -Eliminates uterine disease 

Disadvantages:- Hormone dependent dermatitis 

  • - urinary incontinence
  • - non reversible procedure
  • - surgical complications
  • 40% - incomplete removal of ovarian tissue
  • 20% - fistulus suture reaction - Flank App]
  • 15% - Adhesions with colon and other viscera.
  • 10% - Granulomas affecting kidney and ureter
  • 5% - Ligation of a ureter
  • 20% - infected uterine stumps
  • - obesity/wt. Ioss
  • - cost? 

3.7.2 CASTRATION:

Most common

  • - Prevent/discourage roaming/marking
  • - eliminates coitus and hence disease transmission through mating
  • - Causes prostatic atrophy
  • - Can be associated with complications with inquinal hernia etc. Surgical complications due to bad technique.