The five “W”s of breed specific legislation (BSL)

PitbullWHO: BSL is typically enacted by policy makers and can affect any breed of dog. Breeds of dogs usually affected by BSL are American Staffordshire Terrier, American Pit Bull Terrier, American Bulldog, Cane Corso, Chow Chow, German Shepherd, Wolf-hybrids etc. It is important to note that many BSL laws ban “pit bull ” dogs, which is not an actual breed of dog. The term “pit bull” encompasses an enormous number of genotypes (genetic make up of a animal) and phenotypes (the physical look of an animal) that cannot be reliable identified.

 WHAT: BSL, also known as breed discriminatory legislation is basically a set of laws that impose certain restrictions on owners of specific dog breeds in the hopes of decreasing human dog bite injuries. The most severe form of BSL is a complete ban, meaning no banned breed dogs are allowed to live in a specific area. There are also incomplete forms of BSL including mandatory spay and neuter, muzzle laws, special licensing or liability insurance, confinement restrictions etc. To date, there has not been any supportive scientific evidence that BSL is actually effective in promoting human safety and decreasing dog bit incidents.

WHERE: BSL is far reaching and still exists in many areas of the world today including many municipalities in US states, Ontario and Manitoba, Canada as well as many international locations such as Australia, Brazil, Singapore and the UK.BSL states

WHEN: BSL became popular in the 1990s and early 2000s. However some locations have still been recently enacting BSL as well. The good news is that many areas, including approximately 20 US states, have begun to pass legislation actually prohibiting BSL from being enacted. The issue remains however that in those states, some municipalities still try to enforce previously enacted BSL and do not recognize the state’s prohibition of BSL laws.

WHY: BSL is a commonly used method of trying to decrease the number of dog bites in an area. The main goal of BSL is to promote human safety by reducing the number of “dangerous” dogs who could potentially bite humans. The problem with this band-aid approach is that the etiology of dog bites is multifactorial and addressing the larger issue of dog bites cannot be effectively done by only addressing one factor alone — dog breed. Additionally, dog breed has not been identified as a factor contributing to dog bites in the scientific literature on this topic to date.

It is important to note that no humane welfare organizations support BSL and that there has been an increasing movement towards prohibiting BSL.  Organizations that do NOT support BSL include the American Bar Association, American Veterinary Medical Association (AVMA), American Society for the Prevention of Cruelty to Animals (ASPCA), American and Canadian Kennel Clubs, American Animal Hospital Association and many more.  Even the Obama Administration released a statement in August 2013 in opposition of BSL that stated “Research shows that bans on certain types of dogs are largely ineffective and often a waste of public resources”.  Additionally, the expenses of BSL are often extremely high to animals shelters and include many intangible costs such as volunteer and staff time and emotional investment, shelter support of relinquished animals due to BSL, and euthanasia costs — not to mention the large number of dogs lives that are lost.President dog

A 2010 veterinary paper published in the Journal of Veterinary Medicine (JAVMA) written by Drs. Patronek, Slater and Marder introduced the concept of Number Needed to Ban (NNB) as a novel method to illustrate the ineffectiveness of BSL. Using the human epidemiological equivalent of Number Needed to Treat (NNT), one can calculate the number of dogs needed to be banned in order to prevent one single dog bite. In human medical intervention, the NNT typical ranges from 10-100s; however using this method, up to 100 000 dogs would have to be banned to prevent different outcomes such as hospitalization due to dog bite, insurance claims etc. They easily demonstrated how ineffective and impractical BSL is.

Screen Shot 2014-06-01 at 2.35.31 PMNewer multidisciplinary approaches have been used in a couple locations (see below for an example from Calgary Alberta) and are thought to be much more effective in promoting human safety. These approaches emphasize the importance of responsible pet ownership regardless of dog breed or type. Active community involvement and education, especially for children who are the most at risk population for dog bite injury, are key features of this approach. However, these approaches take effort and time to implement.  If we want to be more effective in reducing dog bite injuries, it is imperative that all stakeholders explore methods of achieving this goal that don’t result in unnecessary death for dogs based on breed.

Additional Resources:

American Veterinary Medical Association (AVMA)


American Humane Association:


America Society for the Prevention of Cruelty to Animals (ASPCA)

Humane Society of the United States (HSUS)

Animal Legal and Historical Center:

American Bar Association:


Kitten, puppies and ascarids, oh my!

ascarids_2As kitten season marches on, shelters across the country are pulling out their Strongid and their Nemex and are vigorously deworming kittens. It is common knowledge that all young animals have worms, and that frequent deworming is necessary. But why is that? This week we will be diving into the specifics of the large roundworms of puppies and kittens, also known as ascarids. Ascarids are some of the largest, hardiest and most common worms seen in our domestic animals. Cats and dogs each have their own, unique ascarid known as Toxocara cati and Toxocara canis respectively. They can also both be infected with a less common ascarid called Toxascaris leonina. Ascarids are commonly 10 – 15cm and are easily seen in the feces of infected animals.

Adult ascarids live in the intestinal tract of dogs and cats and their eggs are shed in feces. The eggs themselves have a thick, sticky, tough outer shell which protects them from the environment. This is why the eggs tend to get stuck in fur or carpet, and are hard to destroy. The eggs in the feces take 2 weeks of growing in the environment before they are infectious, which is why prompt cleaning is so important in a shelter. Eggs are eaten by the animal when they eat anything which has been contaminated with feces, groom themselves, etc. Eggs can also be eaten by other animals such as rodents, who are then infective to dogs or cats if consumed.

The eggs hatch in the stomach of the animal, but do not take a direct route to the intestines. The baby worms migrate through the body, passing through the liver and lungs in their way to the small intestine. Occasionally larvae are lost on their way to the gut, and become trapped in other tissues such as kidneys or muscle, where they do not develop and become dormant cysts. In a pregnant dog these cysts  are activated in the last trimester, and the worms migrate across the placenta to infect the puppies. Thus, puppies are born with worms already growing inside. Similarly in cats, the worms migrate to the mammary glands and are shed in the milk to the newborn kittens.5735449110_bd2f3cdb4d_z1

Normally, infection takes a month or two  from the time an adult animal eats the egg until the worms are fully developed. In puppies it can be much sooner, due to the prenatal infection (3 weeks), which is why early deworming of puppies is so important. Relative to a puppy’s intestinal size, even a small number of 10cm worms can cause serious gastrointestinal upset or even death. Kittens, on the other hand, take longer to develop adult worms because they are infected after birth, but should still be dewormed on a similar schedule as puppies.

Only pyrantel pamoate (Strongid, Nemex) is labeled for use in puppies and kittens as early as two weeks of age. Because this drugs is inexpensive and relatively safe, it is usually the go-to for shelters. Puppies and kittens should be dewormed every two (2) weeks until at least 12-16 weeks of age, by which time they are hopefully adopted. Many other products are effective against ascarids, but toxicity and off-label usage is a concern.

Remember, keeping a clean  environment will go a long way to preventing reinfection of young animals! Killing ascarid eggs is very challenging and they can stay viable in the environment for extended periods. Thoroughly clean surfaces to mechanically remove eggs, then use diluted bleach to strip away the protein layer of the eggs, leaving them vulnerable to desiccation. Play yards and outdoor spaces are impossible to clean and heavily contaminated spaces may require a fresh layer of dirt or gravel placed on top. This is just another good reason why play yards are not for puppies!

I hope you’ve enjoyed this information about ascarids in puppies and kittens. Stay tuned until next week for more parasitology fun!