title: Some observations on the seasonal incidence and frequency of oestrus in breeding bitches in Britain.
mesh_terms: D000818:Animals; D001947:Breeding; D004285:Dogs / Q000502:physiology*; D004739:England; D004971:Estrus; D005260:Female; D011247:Pregnancy; D012621:Seasons; D013997:Time Factors; D014852:Wales