Alcohol diluent provides the optimal formulation for calcium chloride non-surgical sterilization in dogs

Acta Veterinaria Scandinavica

Raffaella Leoci²  Giulio Aiudi²  Fabio Silvestre²  Elaine A Lissner¹  Giovanni M Lacalandra² 

[1] Parsemus Foundation, Berkeley 94702, CA, USA

[2] Department of Emergency and Organ Transplantation (DETO), Section of Veterinary Clinic and Animal Production, University of Bari Aldo Moro, SP per Casamassima km 3, Valenzano, BA, Italy

关键词: Population management;    Nonsurgical sterilization;    Dog;    Chemical castration;    Canine;    Calcium chloride;   

Others  :  1082535
DOI  :  10.1186/s13028-014-0062-2

 received in 2013-06-06, accepted in 2014-09-05,  发布年份 2014

【 摘 要 】

Background

Surgical castration is widely used to sterilize male dogs, but has significant impacts on time to perform the operation, recovery of the animals as well as cost, which can limit population control programs. Previous research has shown intratesticular injection of calcium chloride dihydrate (CaCl₂) in saline to be a promising alternative to surgery. However, long-term azoospermia was not maintained at dosages low enough to avoid side effects. In the search for an optimized formulation, the current investigation is the first study on long-term sterilization effects of intratesticular injection of CaCl₂ in either lidocaine solution or alcohol in dogs. CaCl₂ at 20% concentration in lidocaine solution or alcohol was administered via intratesticular injection to groups of 21 dogs each. The treated animals were examined at 2, 6, and 12 months for sperm production, blood levels of testosterone, and side effects; at time zero and 12 months for testicular size and semen volume. The experimentally treated animals were compared to a control group receiving saline injection only.

Results

Testicles of dogs treated with CaCl₂ in either diluent significantly decreased in size. After administration of CaCl₂ in lidocaine solution, sterility was achieved for at least 12 months in 75% of treated dogs. However, optimal long-term contraceptive effectiveness was achieved with CaCl₂ in alcohol, which resulted in azoospermia over the 12-month study period. Testosterone levels significantly decreased following treatment with CaCl₂, and sexual activity disappeared. Although testosterone returned to baseline levels by 12 months for the group treated with CaCl₂ in lidocaine, dogs injected with CaCl₂ in alcohol had a 63.6% drop in testosterone level, which remained at the low end of physiological range throughout the study. No adverse effects were noted.

Conclusions

A single, bilateral intratesticular injection of 20% CaCl₂ in 95% ethanol was a reliable method for induction of sterilization in 18–28 kg male dogs in this study. The approach showed long-term efficacy and reduced sexual behavior. This chemical method of sterilization might provide an effective, efficient alternative to surgical castration that can have positive impacts on dog welfare.

【 授权许可】

   
2014 Leoci et al.; licensee BioMed Central Ltd.

【 图 表 】

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