According to the National Greyhound Association (NGA), there are 300 greyhound breeding facilities and kennels in the United States. Around 60 of these are in Iowa, with a large number also located in Kansas. Breeding kennels are also known to be located in the following states: Arizona, California, Colorado, Connecticut, Florida, Iowa, Mississippi, New Mexico, North Carolina, Oklahoma, Pennsylvania, Tennessee, Texas, Utah, Washington, and West Virginia.
Females are impregnated, many through artificial insemination by a veterinarian, and produce their litters on site. At a few months of age, puppies' right ears are tattooed with their birth date and order and 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. GREY2K USA analyzed two forms of whelping data provided by the NGA from 2012-2014: aggregate data and individual data. What was discovered is that in each of these three years, the number of puppies reported as registered racers in the aggregate data was significantly lower than the number of puppies born according to individual whelping reports. The discrepancy amounted to 8,422 puppies that were not accounted for, effectively becoming disappeared puppies. The NGA stopped providing complete individual data in 2015.
As dog tracks close, the number of greyhounds bred for racing continues to shrink. A total of 6,213 individual dogs were registered to race in 2018 as compared to 20,365 in 2008, a decline of 69%. 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.
The number of dogs being used for racing is also on the decline. According to industry records, the number of dogs racing at commercial tracks fell from 9,125 in February 2018 to 8,252 in February 2019, a drop of nearly 10%.
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.