Because they cannot rehome the ones they have , so any with behavioural problems or old or just been in kennels for too long tend to get put to sleep , even healthy dogs with no problems get put to sleep , it all costs money to keep strays and abandoned dogs and money does not grow on trees , and with the current problems with money people are dumping their dogs as they cannot afford to keep them any more . I urge you as i posted before to reconsider breeding , even your JRT , as i said co you know 10 people who want one ??? not saying she would have 10 but you can never tell untill they arrive.
Read through some of the threads on here about breeding and see how much hard work goes in to doing it from start to finish ,

In an ideal world we could all keep as many dogs as we liked and there would be no homeless dogs or dogs that had been abused or killed , its not as simple as you think .

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