Photo by benjamin lehman on UnsplashFor every human born, 15 puppies and 45 kittens are born, so there will never be enough of us to care for all of them!  Add to that the fact that limiting your pet’s ability to reproduce could actually keep him or her safer and healthier, it is important that, as a pet parent, you have the conversation with your veterinarian as to whether surgery is the best move, and the correct timing to spay or neuter your pet.  The Humane Society of the United States (HSUS) claims that 6 to 8 million cats and dogs enter shelters every year, and sadly, more than half of them are euthanized.


By all accounts, implementation of spay/neuter programs has been pivotal in reducing overcrowding in shelters, and over the last decade, great strides have been made in getting pet parents to understand, and then act upon, the importance of having their pets spayed or neutered.  A Maddie’s Fund sponsored study, led by the Humane Society of the United States (HSUS), found that serious messaging, centering on euthanasia due to overpopulation, is more influential than low-cost talking points when trying to influence people to get their pets “fixed”.  Additionally, when veterinary professionals address the issue, it is better received than when celebrities plead the cause.  Cute and funny appeals about spay/neuter also tend to miss the mark when attempting to sway people to get their pets fixed, while another key element the study found, was that when people were made aware of their local statistics, they wanted to be part of the solution.


While working on messaging and increasing the numbers of pets getting spayed or neutered this decade, for the most part, the process continued with surgical sterilization.  For females, the typical spay, consists of an ovariohysterectomy, where the ovaries, fallopian tubes and uterus are removed, therefore preventing reproduction and eliminating heat cycles and related breeding behavior. Variations to the surgery (hysterectomy) include removing the uterus and part of the fallopian tubes to prevent reproduction, but leaving the ovaries, allowing for the production of hormones, and therefore, behaviors associated with breeding. Health benefits from these surgeries can include lowering risks of mammary cancer, ovarian tumors and pyometra, a life-threatening infection of the uterus.


Male dogs and cats typically go through an orchiectomy, or neuter (sometimes referred to as complete castration) where the testes are removed making the pet unable to reproduce and eliminating breeding behaviors.  Health benefits include no benign prostatic enlargement, no testicular tumors and no perineal hernias.  An alternative procedure is the vasectomy when only the vas deferens, which carries sperm from the testes, are removed, making the animal unable to reproduce, but testes remain and will produce hormones, so behaviors associated with breeding likely remain.


In spite of the success of these types of gonadectomies, more remote communities lack skilled veterinary surgeons, supplies and recovery space for the animals.  In other areas, pet owners resist surgical practices due to cultural or religious beliefs.  While funding just doesn’t exist in others.  Irrespective of the reasons, a great need still exists for faster, less-expensive means of limiting pet overpopulation in many regions.  In 2014, non-surgical sterilization, Zeuterin® (zinc gluconate) was approved by the FDA as an intra-testicular injection to chemically disrupt enough testosterone producing cells to make a dog sterile.  Most patients still required sedation, and long-term studies hadn’t been completed, but unfortunately, the drug stopped being available in the U.S. just two short years later.


Since surgical spays and neuters are well accepted in the United States, there is not a lot of pressure to find alternatives, particularly in our companion dog population, but as mentioned above, some areas could benefit from options.  Most research is targeted at those populations not easily accessible for surgery, wild horses, deer and feral dog and cat colonies.  For this reason, Found Animals continues to offer veterinary scientists and great thinkers of all types a $75 million challenge to find a non-surgical sterilization method for dogs and cats, while the Alliance for Contraception in Dogs & Cats analyzes the products available and makes that information available.


As we move into the next decade, and wonder what we can expect to see in the forms of non-surgical alternatives to spay-neuter, chemical contraception, hormonal birth control and immunocontraception (where the pet’s own immune system, likely via a vaccine, will be used against his reproductive systems) will likely be riding the research wave.  Several of these applications have been developed and tested with promising results, but unacceptable side effects, so like so many things…time will tell.  In the interim, surgical spay/neuter does vastly reduce euthanasia due to overcrowded shelters, and is safe when pet parents discuss options and timing with their veterinarian.  It is also important too, to vet your vet for the sake of your pet!  Dogs and cats are part of the family, so be your pet’s healthcare advocate.