The city shall provide and maintain a suitable shelter for the impounding of the animals. The shelter may be either constructed and operated by the city, or the city may enter into a contract with a veterinarian or other suitable person, or a corporate or government agency for the supplying and operation of the same. The shelter shall be constructed so that the animals of different kinds and of different sizes and sexes may be segregated, and shall be maintained in a safe and sanitary condition. All animals confined in the shelter shall be regularly fed, watered and treated in a humane manner.