Why does my pet shed?

Shedding is a normal part of your pet’s hair-growth cycle. Each hair goes through several growth phases, including:

  • Anagen: an active growth period during which the hair grows to its genetically-determined length
  • Catagen: a transitional phase from anagen to telogen
  • Telogen: a resting phase that occurs after the growth period and lasts until the hair falls out

Pets with continuously growing hair, such as poodles and shih tzus, have a hair cycle dominated by the anagen phase that can last for several years as the hair grows to its natural length determined by genetics. Once the hair has stopped growing and enters the telogen phase, a new anagen hair develops and the telogen hair is shed. This explains why some breeds have long hair that must be trimmed regularly.

Other pets have a telogen-dominated hair cycle where a brief anagen phase (between one month and a year) produces short hair that is kept during a longer telogen phase, which can last for several years.

Genetics determine a pet’s type of coat, growth cycle, hair length, and amount of shedding. Dog breeds such as collies and Siberian huskies have a thick undercoat and continuously shed a significant amount of hair, whereas breeds such as beagles and pugs have less hair and therefore shed less.

Why does my pet shed more in the spring?

Aside from genetics, seasonal weather fluctuation most strongly influences shedding. Most breeds of dogs experience a mass shedding during the spring and fall as the weather changes and temperatures go to extremes. Animals develop a thick fur coat in preparation for cold winter temperatures, then shed in the spring to make way for a thinner summer coat. Many pet owners are surprised to find that pets also shed their summer coats before bulking up again for winter. Coat changes will not be drastic in indoor pets, but are obvious in pets who spend a lot of time outdoors.

How can I reduce my pet’s shedding?

While the amount your pet sheds cannot be changed, the best way to prevent pet hair from accumulating in your home and on your clothes is to brush your pet daily. Ask your AAHA-accredited veterinarian to recommend a brush or comb that will work best for your pet’s coat, then familiarize your pet with regular brushing sessions. Work through the entire coat, parting the hair to get close to the skin and remove the loose undercoat. Regular bathing also helps remove loose hair. Pets with continuously growing hair often need professional grooming every four to six weeks to avoid painful matting.

What if my pet has abnormal hair loss?

While normal shedding is part of a healthy hair cycle, excessive shedding, a thin hair coat, or bald spots may indicate a medical condition that your veterinarian should evaluate. Many abnormal conditions and health problems cause hair loss, including:

  • Stress
  • Poor nutrition
  • Skin infections caused by bacteria or fungus
  • Parasites, such as lice, mites, and fleas
  • Allergies, which can be caused by environmental allergens or food ingredients
  • Pregnancy or lactation
  • Systemic diseases, such as liver, kidney, or endocrine disorders
  • Immune system disorders
  • Cancer

Pets with abnormal hair loss always should be examined by a veterinarian to determine the cause. Also, normal shedding does not cause irritated, bumpy, or crusted skin, so these signs make a veterinary appointment necessary.