Trial of calcium chloride to fix dogs succeeds in Nepal

YORK,  U.K.–The First International Conference on Dog Population Management concluded in York, United Kingdom on September 8, 2012 with optimism that calcium chloride–which can be made for less than the cost of bottling it–may already be suitable for widespread chemosterilant for use in male dogs.

Recent advances came as a surprise to Parsemus Foundation medical research programs director Elaine Lissner, who has funded calcium chloride trials for several years.  “At the November 2011 Animal Grant-makers meeting,” Lissner told ANIMAL PEOPLE, “we informed other funders about research on calcium chloride dihydrate nonsurgical male dog and cat sterilization, and showed how simple the sterilant is to make, mixing it right at the lunch table.  The Greenbaum Foundation told grantees about it.  But we heard no more about it until August 2012,” when the Greenbaum Foundation reported successful use of calcium chloride by an organization called DREAMS in the Kathmandu Valley of Nepal.

The Nepal deployment was “the first known large-scale field use” of calcium chloride as a chemos-terilant, Lissner recounted, and the first to involve enough dogs to see if any side effects might develop in dogs at a rate of less than one in 100 treated.

“The largest field use before that was in Kolkata, India,” Lissner said, and involved only 52 dogs, producing results not yet published.

DREAMS,  short for Devoted Radical Environment Animal Movement Society, describes itself as a Kathmandu-based nonprofit society that “provides food, shelter and much needed medical treatment to stray animals.  There is a large dog population inside and outside of the valley,” the DREAMS self-description continues.

“The Kathmandu Metropolitan City does mass killing of strays.” DREAMS, along with several other nonprofit organizations, seeks to “control the dog population and save lives.”

DREAMS veterinarians Arjun Aryal and Awadesh Jha, with technician Kailash Thapa, injected the testicals of 766 male dogs with a solution of calcium chloride dihydrate and the anesthetic

Lidocaine as part of their spring 2012 anti-rabies vaccination and sterilization drive.  The field trial included 324 street dogs, 301 pets, and 141 “community dogs,” who are fed regularly but are not associated with any one household.  The DREAMS team conducted conventional surgical spays on 531 female dogs from the same neighborhoods.

“Follow-up was done only for the community and owned dogs,” Aryal and Jha reported, as re-capturing the street dogs for examination proved to be impractical.  “Visits were done one, three and seven weeks after” the calcium chloride sterilizations.   “No side effects were noticed except restlessness for few days,” Aryal and Jha said.  “Some of the dogs had swollen testicles.  No other pronounced complaints were found.”

Several other researchers presented findings pertaining to calcium chloride at the York conference, including Italian veterinarian Raffaella Leoci, whose work affirms the use of Lidocaine with calcium chloride.  Earlier research used alcohol as a local anesthetic instead of Lidocaine.

Of particular interest to Lissner was learning that because calcium chloride is already widely available for pharmaceutical use, it can be used as a chemosterilant for animals in much of the world without having to go through the multi-million-dollar process required to register it  as a chemosterilant in the U.S.

The potential use of calcium chloride as a chemosterilant for cattle was first noted by L.M. Kroger at the Washington State University College of Veterinary Medicine in 1977.  Kroger did the first experimental trial in dogs in 1978.  But 20 years elapsed before veterinarian P.K. Samanta began experimenting with calcium chloride in connection with street dog sterilization in Kolkata, India,  in 1998.  The Parsemus Foundation has funded follow-up studies in Kolkata, including extending the approach to sterilizing male cats.  Studies of the use of calcium chloride to sterilize male cats are also underway in Turkey.