Adult-onset lymphoplasmacytic orchitis in a Labrador retriever stud dog.

A formerly fertile 5-year-old 45-kg Labrador retriever was evaluated for azoospermia noted during routine semen collection for an artificial insemination. Over the past 3 years, the dog had sired 4 litters of anticipated size for the breed out of 5 breedings, the most recent a litter of 10 conceived and whelped 2 months previously. Physical examination findings were normal with the exception of bilaterally small and soft testes.