Free roaming dogs not only transmit diseases to livestock and humans but also pose a threat to human lives
Sterilization is critical for management of overpopulation and related disease control concerns. When effectively delivered and combined with vaccinations, it provides humane and effective way to reduce the number of animals living on the streets, and improves the health of those who persist. The untrammelled growth of a dog population has a negative impact on public health and creates socioeconomic and animal welfare problems. Free roaming dogs not only transmit diseases to livestock and humans but also pose a threat to human lives in the form of dog bites and produce nuisance in the form of barking and griming fields. Dogs are the major vectors for deadly zoonotic disease rabies and are of particular concern for humans and livestock. As per reports put forth by Garde et al., 2013 it stated that canine mediated rabies kills between 30,000 and 60,000 people annually worldwide.
In our valley large number of dog bite attacks have taken place for the last so many years & if we have a look towards the dog bite statistics, nearly 30,711 dog bite cases have been registered at an antirabies clinic at the SMHS hospital in Srinagar from 2012-13 to 2017-18 up to September (GK) suggesting recurrent dog bites. At this present alarming scenario a variety of options are needed for population control with the worldwide overpopulation of dogs. The official statistics also divulge that stray dog bite cases over the years is rapidly swelling viz:- 1724 cases reported in 2016-2017, and around 5496 dog bites have been outlined between 2017 to feb 2018 in Srinagar.
As we are aware of the fact that to perform a single dog surgery it requires a huge cost from sedation/anaesthesia of dog up to post operative care. In order to sterilize dogs at low cost the tool available with us is to replace surgery with the use of chemical compounds to sterilize the animal. For effective dog population management, nonsurgical or chemical sterilization is increasingly advised as deserving priority for development because of its potential to be more cost effective than surgical sterilization. Although surgery is the safe procedure and most effective method but at the same time it is also expensive, time consuming, and needs skilled surgeons, so use of non-surgical sterilization methods would make male sterilization inexpensive, easy and faster and large number of male dogs can be tackled within short period of time. Chemical sterilization includes hormonal methods, immuno-contraceptives, and inorganic Chemosterilants. The technique for said methods demand intratesticular injection of various approved chemicals via; – calcium chloride, Zinc gluconate, and hypertonic sodium chloride (NaCl) solution in dogs to produce successful results. Following intratesticular injection of calcium chloride, necrosis, fibrosis and degeneration of seminiferous tubules and Leydig cells occurs, eliminating the production of spermatozoa, testosterone and sperm counts in a dose-dependent manner in male dogs. It causes permanent sterilization and is a simple alternative method to surgical castration. The procedure is relatively pain less, less time consuming, eliminates risk of complications from anaesthesia and surgery, need for post-procedure care and observation is also minimal, fewer scope of infection and bleeding.
Another relevant study in favour was conducted by Kwak and Lee, (2013) which documented that Hypertonic saline is another solution that is inexpensive and easy to administrate & when injected bilaterally into the rat testes caused coagulation necrosis of testes and produced severe degenerative changes in testicular seminiferous tubules thus can be useful in canine sterilization. As far as the sterilization of bitches is concerned there is no permanent form of chemical neutering for the female but recently a study on heifers was conducted by Cavaleri and Hayes 2017, which stated that following administration of calcium chloride in ethanol transvaginally, and intraovarian initiate complete ovarian atrophy without apparent pain.
Dog bites are a serious consequential public health issue that foist considerable physical and psychological damage on victims and incurs innumerable masked costs to mankind. Dog welfare, public health, and environmental protection are improved by mass sterilization and vaccination programs, it is exigent to develop programs that are capable of provide large scale contraception to dogs humanely, efficiently, with minimal technical requirements, and cost effectively. The availability of a long acting immunocontraceptive vaccine which could be administered by lay technicians in the field would be a powerful tool for controlling dog population.
Chemical orchidectomy with chemical agents has been suggested as a fast and low cost alternative which could be used in a wide range of canine populations, especially in poor regions where problem is more intense (Soto et al., 2007). Chemical sterilisation can play a role in the sterilisation of animals but careful attention to dose, volume, chemical composition, administration technique are needed to avoid adverse side effects and emergencies.
(Author is Veterinary Assistant Surgeon, GMC Srinagar (Mvsc. Surgery))