Chicken & Beef Entrée in a delicious loaf with complete & balanced nutrition to help keep adult dogs active and healthy
Supports lean muscle and beautiful coat for adult dogs
Supports healthy joints, lean muscle, and beautiful coat for large breed dogs
Supports lean muscle and beautiful fur for adult cats
Improves Everyday Ability to Get Up & Go
Precisely balanced nutrition with the delicious taste of minced turkey & liver to help fuel the energy needs of cats during the prime of their life
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An Orange cat eating from a bowl filled with mixed food
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Your cat's immune system is a silent superhero that helps protect them from harm. Constantly on the lookout for invaders, anything their body registers as a foreign substance can trigger an immune response. When your kitty eats, inhales or absorbs something the body considers a threat, it triggers a series of processes to alert the appropriate part of the immune system to the potential source of harm.
Without an immune system, your cat would be defenseless against dangers from the outside world and inside their own body. The immune system's main functions include:
Detecting and destroying harmful germs, such as parasites, bacteria, fungi and viruses.
Recognizing and neutralizing harmful environmental substances, such as toxins and chemicals.
Fighting internal changes that can lead to disease, such as cancer cell development.

But what is the immune system, exactly? From a big-picture organizational standpoint, the immune system is made up of organs, cells and proteins.
The skin is your cat's largest organ and one of the first lines of defense, acting as a barrier to keep foreign substances from entering the body.
From germ-neutralizing enzymes in saliva and stomach acid to antibody-generating cells in the intestinal walls, your cat's gastrointestinal (GI) system is a key player in healthy immune function.
Mucous and enzymes in the respiratory tract help trap and neutralize germs and other harmful substances.
Your cat's lymph nodes, thymus gland, spleen, gut-associated lymphoid tissue (a protective lining found in the GI tract) and bone marrow are responsible for many functions that help the body fight infection and disease. This includes producing immune cells, filtering germs and triggering antibodies.
Immune system cells create antibodies, detect and destroy abnormal cells, support cellular repair and more. Some of these hardworking immune cells include:
Lymphocytes
Neutrophils
Macrophages
Eosinophils
Think of cytokines as immune system messengers that deliver signals between cells.
Antibodies work hard to form immune complexes, label substances for removal and block viruses from entering your cat's body.
When your cat's immune system is functioning optimally, you likely don't give it much thought. But when this unsung champion is taken down a notch, your cat is more vulnerable to illness, infection and disease.
Some factors that can compromise feline immune function include:
Poor nutrition
Viral infections
Chronic stress
Chronic disease
Immune-suppressing medications
Genetics
Cancer
Congenital (present at birth) disorders
Your veterinarian can help you manage underlying health conditions and recommend strategies to reduce feline stress.

Your cat's microbiome is key to healthy immune function, energy, digestion and overall organ function.
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Dr. Laci Schaible, DVM, CVJ
Offering your cat a complete and balanced cat food is the foundation of overall health and well-being, including the immune system. Here are some key players in immune system support.
Antioxidants help neutralize free radicals, unstable molecules that damage cells and even DNA. Some important antioxidants for cats include:
Vitamins, such as vitamins A, C, E and K
Amino acids, such as arginine, cysteine, lysine and taurine
Carotenoids, such as beta-carotene, lutein and lycopene
Minerals, such as copper, selenium and zinc
Research shows that certain nutritional components may help boost cats' ability to fight infection and disease. For example, one study showed that supplementing cats with ingredients such as salmon oil, nucleotides and arginine — an essential amino acid and antioxidant for cats — resulted in increased immune activity.
Your cat's microbiome is key to healthy immune function, energy, digestion and overall organ function. Prebiotics, or prebiotic fiber, nourish your cat's microbiome by supporting the unique balance of beneficial bacteria in their gut. Your veterinarian can point you toward a food formulated with prebiotic fiber to support microbiome health.
Your cat's immune system is a complex network of organs, tissues and cells that helps protect them from internal and external threats. While there's no single best cat food to boost immune system function, choosing complete and balanced nutrition tailored to your kitty's needs will provide them with the best vitamins for cats' immune systems. When in doubt, ask your vet for their recommendation to promote your cat's wellness from the inside out.
Dr. Laci Schaible is a small animal veterinarian, veterinary journalist, and a thought leader in the industry. She received her Doctor of Veterinary Medicine from Texas A&M University and her Masters in Legal Studies from Wake Forest University.
Delectable chunks with tender tuna smothered in a rich gravy
Improves Everyday Ability to Get Up & Go
Precisely balanced nutrition with the delicious taste of minced turkey & liver to help fuel the energy needs of cats during the prime of their life
Supports lean muscle and beautiful fur for adult cats
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Our low calorie formula helps you control your cat's weight. It's packed with high-quality protein for building lean muscles, and made with purposeful ingredients for a flavorful, nutritious meal. Clinically proven antioxidants, Vitamin C+E, help promote a healthy immune system.
Our low calorie formula helps you control your cat's weight. It's packed with high-quality protein for building lean muscles, and made with purposeful ingredients for a flavorful, nutritious meal. Clinically proven antioxidants, Vitamin C+E, help promote a healthy immune system.