Boxer runts of the litter are the result of being the last egg fertilized during the female boxers fertility cycle. While runts are the smallest of the litter during the first 8 weeks of the litter's life, runts have the potential to be the largest boxer of the litter. Because all boxers are bred to meet breed characteristics, nutrition can have a significant influence on how large or small a boxer runt will grow to be.
The breed standards of the Boxer set by the American Kennel Association require males to be 22 1/2 to 25 inches at the shoulders, and females should be slightly smaller, only reaching 21 to 23 1/2 inches at the shoulder. Boxers are described as being lean-muscled, medium-sized dogs that should not weigh under 55 pounds or over 70 pounds when fully mature. Runt or not, a quality breeder expects all boxer pups to meet the breed standard when mature.
While breed standards inform boxer owners of the acceptable limits of height and weight, companion boxers not used for breeding or show can be any weight as long as they maintain a healthy body mass index level for the runt's overall size. Boxers should have a lean, thick-muscled neck that should not show signs of obesity or undernourishment. Some runts can reach up to 85 pounds as a mature adult, and while this weight is not correct for the breed standard, it does reveal how large a runt can grow to be.
Health and Nutrition
Many of the health problems that are common in runts are directly related to nutrition, such as failing to thrive. Weak bones, under ideal weight and slow growth are a result of the runt being too small to access food -- not because he is the runt. Quality breeders recognize runts within the first few hours, and to prevent nutritional deficiencies, they ensure all pups have access to the mother's first milk and continue to ensure that each pup takes in enough nutrients to maintain excellent health until weaned.
Because many of the problematic illnesses and undesirable traits that are a result of nutrition, it is important for runts to maintain an quality diet within the first two years while the boxer pup is still converting nutrients into growing energy and body mass. Good-quality dry kibble can be fed as a stand alone or as a supplement with a raw-food diet. Organic and raw diets are a quality source of natural vitamins, minerals and protein that canines require to be healthy from puppyhood to adulthood. Additionally, raw and organic diets are quickly processed by the body, which means pups eat less, stay fuller and produce less waste.