Chihuahua (dog) The affected chihuahua will hold its leg flexed, and foot off the ground until the quadriceps muscle relaxes and lengthens, after which the animal feels no discomfort and continues with activity. Chihuahuas are also prone to some heart-related disorders, such as heart murmurs and pulmonic stenosis, a condition in which the blood outflow from the heart's right ventricle is obstructed at the pulmonic valve. Chihuahua (dog) The Chihuahua () is the smallest breed of dog and is named after the state of Chihuahua in Mexico. Chihuahuas come in a wide variety of colors, and two coat lengths. The Chihuahua's history
McNab dog McNab dog The McNab Dog - commonly called McNab Shepherd or McNab Collie - is a herding dog that originated in the Mendocino region of Northern California. The McNab was bred to withstand the tough conditions found in California such as heat, burrs, foxtails, and rugged terrain. Until recently, the McNab was little known outside California, but the last three decades have seen a gain in popularity and geographic dispersal of the breed. The appearance of the McNab can vary considerably. The dog is medium-sized with females standing 16-21 inches at the shoulder and weighing 30-50 pounds and males standing