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ABSTRACT Male dogs and cats were immunized against LHRH in order to evaluate the feasibility of an immunological approach to pet contraception. In the first study, dogs were immunized with 100, 500, or 2500 fIg of LHRH conjugated to tetanus toxoid. A significant decline in serum testosterone (T) levels was observed in all immunized dogs, reaching castration levels in some animals by Week 4 and remaining suppressed in all the immunized dogs through the course of the study. Testicular histology suggested arrest of spermatogenesis (infertility). The effects of "immunological castration" were reversible (study 2): steroidogenesis suppressed by "immunological castration" was restored as antibody titers declined. Effective antibodies were rapidly reinduced in dogs by a single injection of LHRH,-TT. In contrast, the level of antibodies induced in male cats (study 3) was not sufficient for "immunological castration." The conclusion was that active immunization against LHRH could provide a cost-effective, nonsurgical, reversible means to control the fertility of companion animals. INTRODUCTION Pet overpopulation is one of the most serious problems in the field of animal protection. Nationally, animal shelters must destroy more than 5 million unwanted dogs and cats each year (The American Society for the Prevention of Cruelty to Animals). Presently, spaying and neutering are the most practical methods available to control pet reproduction as well as undesirable sexual behavior (spraying, mounting, vocalizing, aggression). Factors of cost and irreversibility make these surgical methods difficult to implement, creating a need for low-cost alternatives. Low-cost methods of humane fertility control may become available through research directed at hormones of the reproductive system. LHRH is a decapeptide produced by the hypothalamus. LHRH acts as the master reproductive hormone through regulation of the release of LH and FSH from the pituitary [1]. In males, LH regulates testosterone (T) synthesis; FSH is necessary for the initiation and maintenance of spermatogenesis [2, 3]. T is needed for spermatogenesis and for the development of secondary sexual characteristics including behavioral characteristics such as territorial marking (spraying), mounting, and aggressiveness. In females, both LH and FSH are required to stimulate the ovarian changes leading to ovulation [4]. In early studies aimed at raising antisera against LHRH, in which high antibody titers were achieved in male rabbits, the testes became atrophied [5]. Since then, it has been shown that inducing sufficient Accepted August 10, 1994. Received April 11, 1994. 'Research was conducted with support of a grant from Geraldine R Dodge Foundation. 2Correspondence: Dr. Anna Ladd, Vaccine Research, Inc., 148 Neptune Avenue, Brooklyn, NY 11235. levels of antibodies against LHRH leads to the suppression of reproductive behavior in both males and females, the suppression of synthesis and secretion of gonadotropins and gonadal steroid hormones, gonadal atrophy, and arrest of gametogenesis [6]. These observations suggested the potential application of immunization against LHRH for the regulation of gonadal functions and fertility in domestic animals [7, 8] and humans [9, 10]. The studies reported here were conducted in male dogs and cats. Only pharmaceutically acceptable materials were used in all studies. MATERIALS AND METHODS Animals Study 1 was conducted in male dogs at White Eagle Laboratories (Doyles Town, PA), a facility licensed by the Food and Drug Administration for conducting studies in accordance with regulations for Good Laboratory Practice. Dogs were maintained in accordance with USDA regulations for the care and use of laboratory animals. Other experiments in dogs and the studies in cats were conducted at the Laboratory Animal Research Center at the Rockefeller University. This facility is fully accredited by the American Association for the Accreditation of Laboratory Animal Care. All experiments were approved by Institutional Animal Care and Use Committees. Animals were injected subcutaneously (s.c.) at the designated time points (see Experimental Design). Two to three milliliters of blood was collected from the jugular vein (cats) or median cubital vein (dogs). Testicular sizes (study 1) were obtained by measuring length and width of testicles with a caliper at the times of blood collection. Thin-needle testicular biopsy (study 1) was performed at White Eagle Laboratories by the attending veterinarian 20 wk after the initial immunization. 1076 |
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I had read an article about the particular meds you are speaking of. I can't rememeber the name right now but I did speak to the vet about it when I was getting ready to neuter lex. First off the meds are fairly new and not totally sanctioned by the FDA. Second off it actually shrivels up the testicles like using steroids does in order to stop the production of semen. Third off the Dr. said it was too risky in his opinion and if it were his dog he would opt for the neutering...which I did. Not sure about your vet but the meds is/was not reversible. It's a one time shot that shrivels up the testicles. There is no turning back from that. |
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So which is it? |
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Hon we aren't researching this, you are. I had my dogs properly neutered so I personally couldn't care less. You are the one who said that 99% of vets will not administer this shot which mean you are the one who made it sound unsafe.. |
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Where did you get this from? It's plagiarism to not quote a source when you copy and paste information |
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The research you posted on LHRH was from 1994. Further research had difficulty replicating those results on a reliable basis and I'm not aware of it being approved for use anywhere. Are you talking about Tardek? I don't think it's used here but it only lasts a few weeks and I've read research where it can increase aggression in some circumstances. |
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If I moved to egypt tomorrow... I would still be an American. Its where you're born, not were you live. |
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