gistfile1.txt

// ==UserScript==
// @name         Hide dog breeds
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       You
// @match        https://www.petfinder.com/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    var jq = document.createElement('script');
    jq.src = "https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js";
    document.getElementsByTagName('head')[0].appendChild(jq);
    jQuery.noConflict();

    var i = setInterval(function() {
        console.log('hidden');
        var breeds = ['bull', 'akita', 'chow chow', 'doberman', 'pinscher', 'german shepard', 'great dane', 'rottweiler'];
        breeds.forEach(function(breed) {
            $('.breed').filter(function() {return $(this).text().toLowerCase().includes(breed);}).closest('li').hide();
        });
        clearInterval(i);
    }, 1000);

})();