According to the National Greyhound Association (NGA), there are 300 greyhound breeding facilities and kennels in the United States. A large number of these are located in Kansas, the home of the National Greyhound Association, as well as in Iowa, Oklahoma, Texas, and West Virginia.
Females are impregnated, almost exclusively through artificial insemination by a veterinarian, and have their litters on site. At a few months of age, puppies' right ears are tattooed with their birth date and order. Later, an individual registration number is tattooed in the left ear. While at these breeding facilities, dogs are often kept outside, in large dirt pens with minimal shelter. Greyhounds spend approximately one year at these locations before they begin race training.
There is also evidence that some greyhound puppies disappear from record. According to Iowa Department of Agriculture and Land Stewardship, the average litter size between 2006 and 2008 was 5.38 puppies. This is remarkably low. National statistics provided by the NGA for the same period indicate a litter size of 6.04. Using the NGA average litter size, a total of 493 Iowa greyhound puppies would not be accounted for during the period 2006 through 2008. Previously, the greyhound industry has defended this discrepancy by stating that there is a natural attrition rate of approximately 5%. However, even after taking this natural attrition rate into consideration, Iowa state statistics still do not account for hundreds of greyhound puppies.
As dog tracks close, the number of greyhounds bred for racing continues to shrink. In the last full year of aggregate data published by the National Greyhound Association, a total of 10,422 individual dogs were registered to race in 2015 as compared to 26,797 in 2001, a decline of 61%. The number of greyhounds adopted into loving homes each year is unknown. In 2011, the National Greyhound Association acknowledged that there are "no cumulative annual records" to track greyhounds once they stop racing.
Ireland reported 2,736 litters in 2013. Using the conservative estimate of six pups per litter, the industry bred approximately 16,416 greyhounds that year. In 2013, 15,576 were registered to race, both for commercial racing and hare coursing. Of these, 9,373 greyhounds remained in Ireland, and 6,203 were exported to race in the United Kingdom. Additionally, older racing greyhounds have been known to be exported to Argentina, Macau, Pakistan, and Spain — all countries where dogs are routinely killed and discarded.
Australia reported 3,006 litters in 2015. Using the conservative estimate of six pups per litter, the industry bred approximately 18,036 greyhounds that year. In 2015, only 11,732 were registered to race, a discrepancy of 6,304 dogs. Australia regularly exports greyhounds to New Zealand, having exported 813 greyhounds between 2009 and 2012. In addition, it is estimated that since 2011, Australian trainers have also exported over 1,700 dogs to mainland China, Macau, and Vietnam, jurisdictions with no animal welfare laws in place.