臺灣街頭流浪犬，絕大多數是被人從家中棄養之家犬，而犬隻在外界遊蕩，易有妨害居家安寧、造成交通意外、糞尿污染、動物與動物及動物與人類間傳染病傳播等問題。家犬被棄養後，遊走街頭、飲食不足、增加罹患疾病的機會，且不符合動物福祉。為因應上述問題以作為國家政策制定與狂犬病等人畜共通疾病防疫的參考，以調查研究及統計分析估算臺灣地區的家犬數目是有其必要性。本研究採用隨機電話調查法（Random Digit Dialing）進行訪談抽樣，另按各縣市的人口分佈，採取樣本比率機率（Probability proportional to size）抽樣法，以估算家犬數量。結果如下：2003年臺灣地區家犬總數為1,355,214隻，養犬戶數佔全國戶數的15.56%，平均養犬隻數為 1.51隻，70.9 %的養犬戶僅飼養一隻犬。比較過去調查紀錄，1999年家犬總數為1,739,424隻、2001年家犬總數為1,480,043隻。1999年到 2001年間，全國家犬總數少了14.91 %，2001年到2003年間則再淢少8.43 %，經比較1999、2001、2003年的結果顯示，每戶平均養犬隻數分別為1.56、1.46、1.51隻，彼此間並無顯著差異( P＞0.05)；而三次調查結果，全國養犬戶百分比分別為25.05 %、18.82 %、16.07 %，具有顯著性差異（P＜0.05）。故可知臺灣地區家犬數量減少並非由於養犬戶養犬隻數減少，而是養犬戶數的降低。
Most of the stray dogs was relinquished by the owners and escaped from household. Stray dogs suffer high mortality and low reproduction, and their quality of life is generally poor due to chronic disease and malnutrition. To make adequate policy, and strategy for prevent and infectious disease between dogs and human, the first step-taken to obtain the real number of household dogs in Taiwan is necessary. his investigation on the total number of household dogs, is by means of collection of data via telephone questionnaire. Interview which is conducted by disorderly random sampling from the residential telephone books of various counties and cities around Taiwan. The number of household dogs is calculated according to the percentage of the number of dog keeping households in various districts. The confidence level of total number of household dogs used is 95%, Z=1.96, and the maximum ratio of the sampling group and the parent group (P)=0.5, confidence level (CL)=95% reliability interval as well as the bound on the error of estimation is allowed within ±1%. A total of 1,355,214 household dogs estimates in Taiwan. In this study showed that each family owned 1.51 dogs, 15.56% of dogs keeping household, and the family of only keeps one dog the percentage is 70.9% in Taiwan, 2003. To compare the data among of 1999, 2001, 2003, the different of number of household dogs reduces 14.91% from 1999 to 2001, and reduces 8.43% from 2001 to 2003. The average number of dogs in household is 1.56, 1.46, 1.51, separately, while among these results showed no significant difference. From comparison of the household dogs number1999, 2001, 2003 in Taiwan, it clearly showed that the number of household dog in Taiwan is drop down sharply, this does relate to the loss the number of dog keeping household, while does not connect to the reduce the average of number in each household.