臺灣人受殖民統治影響，不得不改變過去的養狗習慣。殖民當局將身分游離的狗視為公共衛生之敵，強迫民眾結束過去與狗之間若即若離的關係，這是如何做到的？本文從三方面展開討論。首先，考察權力機制如何透過立法讓「家犬」與「野犬」的觀念落實到民眾生活中；其次，究明以對付狂犬病為名實施的野犬撲殺真相；最後，分析中日開戰以後（1937〜）的擴大撲殺。我們發現二分法的概念加速土狗的野犬化。新規定鼓勵狗主人更負責任，或許有助於減少流浪犬數量，不過，殖民當局計畫性地殲滅牠們，則是臺灣土狗變成少數族類的主要原因。在處理流浪犬方面，日本政府的聲譽令人震驚，而這也讓我們得到反思後來發展的材料。

Due to the impact of colonial rule in Taiwan, Taiwanese people had to change their habits on dog keeping. The colonial authorities regarded roaming dogs as the ＂enemy of the people,＂ especially with regard to public health, and forced the people to end the previous mode of relationship with canines. How it could be achieved? This article discusses from three aspects. First, it examines how did the concept of ＂owned dog＂ and ＂homeless dog＂ be implemented in the daily lives of the people through legislation; secondly, it investigates the reality about the elimination of homeless and abandoned dogs in the name of dealing with rabies; finally, it analyzes the expansion of scope of elimination after the war between China and Japan (1937-1945). We find that Taiwanese dogs became homeless was a consequence of the idea that divided dogs into two major categories. The new rulers encouraged dog owners to be more responsible and it may help reduce the number of roaming dogs. However, the colonial authorities' plan to annihilate them is the most important reason why Taiwanese dogs became minor species. The reputation of the Japanese government about dealing with feral dogs is shocking, but it has allowed us to reflect on the materials that have evolved.