Editing Neutering (section)

====Hormone-Sparing Surgery====
[[Vasectomy]]: In a more delicate procedure than castration, the [[Vas deferens|vasa deferentia]] – ducts that run from the testes to the [[penis]] – are cut then tied or sealed, to prevent [[sperm]] from entering into the [[urethra]]. Failure rates are insignificantly small. [[Animal breeding|Breeders]] routinely have this procedure carried out on male [[ferret]]s and [[sheep]] to manipulate the estrus cycles of in-contact females. It is uncommon in other animal species. Because a vasectomy is usually a more expensive procedure, among pet-keepers it is more often performed on [[Animal show|show animals]], to cosmetically preserve their appearance (though depending upon the [[Animal fancy|fancier organization]], the procedure may invalidate the animal's candidacy for certain awards, or relegate it to a non-[[Pedigree (animal)|pedigree]], generic "household pet" competition division, just as with full castration).

[[Tubal ligation]]: Snipping and tying of [[oviduct]]s as a sterilization measure can be performed on female cats, dogs, and other species; it is essentially the female equivalent of vasectomy, but a more invasive procedure. Risk of unwanted pregnancies is insignificantly small. Only a few veterinarians perform the procedure.

Like other forms of neutering, vasectomy and tubal ligation eliminate the ability to produce offspring. They differ from neutering in that they leave the animal's levels and patterns of [[sex hormone]] unchanged. Both sexes will retain their normal reproductive behavior, and other than birth control, none of the advantages and disadvantages listed below apply. This method is favored by some people who seek minimal infringement on the natural state of companion animals to achieve the desired reduction of unwanted births of cats and dogs.

=====Injectable=====
* Male dogs – Two intratesticular injectable formulations are known to sterilize male dogs. [[Zeuterin]] was approved by the United States [[Food and Drug Administration]] (FDA) for permanent sterilization of male dogs ages three months and older by causing [[necrosis]] of the testicle.<ref>{{Cite web|url=https://www.acc-d.org/available-products/zeuterin-esterilsol|title=Zeuterin|date=5 January 2019|website=www.acc-d.org|access-date=5 January 2019}}</ref> It is not currently available commercially. Calcium chloride dissolved in a variety of diluents have also been studied, with the majority of research and most promising results using calcium chloride dissolved in ethyl alcohol. Calcium chloride formulations can be purchased for use in animals from compounding pharmacies, but the use of calcium chloride for sterilization of males is not approved by the FDA or any other international regulatory agency.<ref>{{Cite journal|last=Leoci|first=Raffaella|date=14 October 2014|title=Alcohol diluent provides the optimal formulation for calcium chloride non-surgical sterilization in dogs|journal=Acta Veterinaria Scandinavica|volume=56|issue=1 |pages=62|doi=10.1186/s13028-014-0062-2|pmid=25317658|pmc=4195956 |doi-access=free }}</ref>
* Male cats – Calcium chloride formulations have also been studied in male cats.<ref>{{Cite journal|last=Jana|first=Kuladip|date=2011|title=Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride|journal=BMC Vet Res|volume=7|pages=39|pmc=3152893|pmid=21774835|doi=10.1186/1746-6148-7-39 |doi-access=free }}</ref> 
* Male rats – [[Adjudin]] ([[Analog (chemistry)|analogue]] of indazole-carboxylic acid), induces reversible germ cell loss from the [[Seminiferous tubules|seminiferous epithelium]] by disrupting cell adhesion function between [[Sertoli cell|nurse cells]] and [[Spermatogonium|immature sperm cells]], preventing [[Spermatogenesis|maturation]].
* Male mice – injection of a solution of the JQ1 molecule to bind to a pocket of BRDT necessary for chromatin remodeling, which gives the proteins that regulate how genes act access to the genetic material<ref>{{Cite journal| first1= Martin M. |last1= Matzuk |first2= Michael R. |last2= McKeown|first3= Panagis |last3= Filippakopoulos |first4= Qinglei |last4= Li |first5= Lang |last5= Ma |first6= Julio E. |last6= Agno |first7= Madeleine E. |last7= Lemieux |first8= Sarah |last8= Picaud |first9= Richard N. |last9= Yu |first10= Jun |last10= Qi |first11= Stefan |last11= Knapp |first12= James E. |last12= Bradner | title=Small-Molecule Inhibition of BRDT for Male Contraception | journal=Cell | date=2012-08-17 | volume=150 | issue=4 | pages=673–684 | url= | doi=10.1016/j.cell.2012.06.045 | pmid=22901802 | pmc=3420011}}</ref>
* Male sheep and pigs – Wireless Microvalve.<ref>{{Cite journal |last1= Jones |first1= Inke |first2= Lucas |last2= Ricciardi |first3= Leonard |last3= Hall |first4= Hedley |last4= Hansen |first5= Vijay |last5= Varadan |first6= Chris |last6= Bertram |first7= Simon |last7= Maddocks |first8= Stefan |last8= Enderling |first9= David |last9= Saint |first10= Said |last10= Al-Sarawi |author-link11= Derek Abbott |first11= Derek |last11= Abbott |url= http://www.eleceng.adelaide.edu.au/personal/dabbott/publications/SMS_jones2008.pdf |title= Wireless RF communication in biomedical applications |journal= Smart Materials and Structures |volume= 17 |issue= 1 |date= 17 January 2008 |pages= 8–9 |doi= 10.1088/0964-1726/17/1/015050 |access-date= 2008-06-25 |url-status= live |archive-url= http://archive.wikiwix.com/cache/20110825090935/http://www.eleceng.adelaide.edu.au/personal/dabbott/publications/SMS_jones2008.pdf |archive-date= 25 August 2011 |df= dmy-all |bibcode= 2008SMaS...17a5050J |s2cid= 31682313 }}</ref> A proposed non-chemical, reversible sterilization method using a [[Piezoelectricity|piezoelectric]] [[polymer]] that will deform when exposed to a specific electric field broadcast from an emitter.  The valve will then open or close, preventing the passage of sperm, but not [[seminal fluid]]. Located in a section of the [[vas deferens]] that occurs just after the [[epididymis]], the implantation can be carried out by use of a hypodermic needle.
* Female mammals – Vaccine of antigens (derived from purified [[porcine zona pellucida]]) encapsulated in liposomes (cholesterol and lecithin) with an adjuvant, latest US patent [https://web.archive.org/web/20061027161320/http://www.pharmcast.com/Patents/Yr2001/June2001/061201/RE37224_Fertilization061201.htm RE37,224] (as of 2006-06-06), CA patent [https://web.archive.org/web/20071029225337/http://patents1.ic.gc.ca/details?patent_number=2137363 2137263] (issued 1999-06-15). Product commercially known as SpayVac,<ref>[https://web.archive.org/web/20031214053009/http://www.spayvac.org/ SpayVac]. Retrieved on early 2003.</ref> a single injection causes a treated female mammal to produce antibodies that bind to [[Zona Pellucida|ZP3]] on the surface of her ovum, blocking sperm from fertilizing it for periods from 22 months up to 7 years (depending on the animal<ref>{{cite conference |url=https://www.aphis.usda.gov/wildlife_damage/nwrc/publications/06pubs/miller062.pdf |title=Long-term Efficacy of Three Contraceptive Approaches for Population Control of Wild Horses |first1=Gary |last1=Killian |first2=Nancy K. |last2=Diehl |first3=Lowell |last3=Miller |first4=Jack |last4=Rhyan |first5=David |last5=Thain |date=2007 |conference=22nd Vertebrate Pest Conference |editor1-last=Timm |editor1-first=R. M. |editor2-last=O'Brien |editor2-first=J. M. |book-title=Proceedings, Twenty-Second Vertebrate Pest Conference |publisher=University of California, Davis |pages=67–71 |url-status=live |archive-url=https://web.archive.org/web/20170213013356/https://www.aphis.usda.gov/wildlife_damage/nwrc/publications/06pubs/miller062.pdf |archive-date=13 February 2017  }}</ref><ref>{{cite web| last1=DeNicola | first1=Anthony | first2= Lowell A. |last2= Miller | first3= James P. |last3= Gionfriddo | first4= Kathleen A. |last4= Fagerstone  | publisher=Northeast Association of Fish and Wildlife Agencies | url=http://www.neafwa.org/html/wildlifeabs.shtml#d | title=Status of Present Day Infertility Technology | date=2007-03-16 | access-date=2007-03-16 |archive-url = https://web.archive.org/web/20070829131847/http://www.neafwa.org/html/wildlifeabs.shtml#d |archive-date = 29 August 2007}}</ref>). This will not prevent the animal from going into heat (ovulating) and other than birth control, none of the  advantages or disadvantages mentioned below apply.