Zinc is an essential trace mineral that plays a crucial role in the overall health and well-being of dogs. Zinc is necessary for several processes, including immune function, cell division, growth, wound healing, and the proper functioning of enzymes.
Adequate zinc intake is essential for maintaining a healthy immune response in dogs, preventing infections, and promoting healing. In this article, I will go over zinc’s role in the body and the different sources of zinc.
Top Seven Benefits of Zinc
- Supports immune function: Zinc is essential for the proper functioning of the immune system, contributing to the activity of white blood cells and the production of antibodies.
- Promotes skin health: Zinc plays a crucial role in maintaining skin health, contributing to proper wound healing, epidermal barrier function, immune function, and anti-inflammatory properties.
- Contributes to insulin function: Zinc is essential for insulin synthesis, storage, and secretion, contributing to proper blood sugar regulation.
- Supports growth and development: Zinc is necessary for proper growth and development in dogs, contributing to bone and muscle growth, reproductive function, and the development of the nervous system.
- Maintains enzymatic activity: Zinc plays a vital role in the proper functioning of several hundred enzymes in the body, contributing to various metabolic processes.
- Promotes healthy digestion: Zinc is essential for maintaining small intestinal health in dogs, contributing to the maintenance and repair of the intestinal lining, including the epithelial cells.
- Contributes to cognitive function: Zinc is necessary for the development and maintenance of cognitive function, including memory, learning, and behavior.
There are more benefits than the seven listed above. I’ve just highlighted the main ones.
Where Does The Body Store The Zinc?
Dogs store zinc primarily in their liver, kidneys, pancreas, bones, and muscles. Smaller amounts can also be found in other tissues and cells throughout the body. Zinc is distributed throughout the body via the bloodstream, and excess zinc is excreted primarily in the urine and feces.
The liver plays a crucial role in regulating zinc metabolism, storing excess zinc, and releasing it into the bloodstream as needed. Zinc is also stored in other tissues, such as the skin, hair, and nails, where it contributes to their growth and maintenance. However, the exact distribution of zinc in the body can vary depending on various factors such as age, breed, size, and overall health status.
Is It Needed Daily?
Yes, dogs need zinc daily as it is an essential mineral that cannot be synthesized by the body and must be obtained through the diet. Excess zinc is excreted primarily in the urine and feces.
Whole Food Sources For Zinc?
Meat, oysters, and zinc supplements are all potential sources of zinc for dogs. Animal meat, particularly beef, and lamb, is an excellent source of zinc for dogs, providing a readily available source of zinc that is easily absorbed and utilized by the body.
Oysters are another excellent source of zinc, containing higher levels of zinc than most other food sources. However, oysters may not be readily available or cost-effective for all dog owners. That said, oysters are a poor choice for dogs with histamine intolerance.
Oysters are a high-histamine food and can trigger histamine intolerance in some dogs. Histamine intolerance is a condition that occurs when the body is unable to break down histamine effectively, leading to an accumulation of histamine in the body and resulting in symptoms such as itching, hives, diarrhea, and vomiting. Oysters contain high levels of histamine, particularly when they are not fresh or have been stored improperly.
Zinc content in oysters can vary significantly depending on their origin and the environmental conditions in which they grow. Canned oysters harvested from the eastern coast of the United States, particularly from the Atlantic Ocean, may have different zinc concentrations (90.95mg/100g) compared to Pacific oysters (16.6mg/100g) found along the western coast of the United States and other parts of the Pacific Ocean.
Factors such as water temperature, salinity, and the availability of nutrients can influence the mineral content, including zinc, in oysters. Interestingly, there is limited data available on the zinc content of oysters from Asia, making it difficult to draw conclusions about their nutritional value in terms of zinc.
Formulating with oysters can be problematic when the oysters used are purchased from the Asian Market because we have no way in knowing if we are going to use the 90.95mg/100g or 16.6mg/100g values. Further research is needed to better understand the variations in zinc levels across different oyster species and geographical locations, including those from Asia, to help us make informed choices.
Zinc supplements can also be used to ensure adequate zinc intake, particularly for dogs who have difficulty obtaining enough zinc through their diet. And while it is a synthetic source, at least we know exactly how much zinc is in a tablet or capsule.
Do Grass-Fed Cuts Have Higher Levels of Zinc?
Grass-fed beef may have higher amounts of zinc compared to conventionally raised beef due to differences in the animal’s diet and living conditions. Conventionally raised beef is often fed a diet of corn and soy, which is high in omega-6 fatty acids but low in omega-3 fatty acids and other nutrients such as zinc. In contrast, grass-fed beef is raised on a diet that consists mainly of grass and other forages, which are rich in zinc and other essential nutrients.
In addition to their diet, grass-fed cattle tend to lead a more natural lifestyle compared to conventionally raised cattle. Grass-fed cattle are typically raised in open pastures, allowing them to move around and graze on a variety of plants and grasses. This natural environment allows grass-fed cattle to consume a wider variety of nutrient-dense foods, which may contribute to their higher levels of zinc.
Moreover, grass-fed cattle are not subjected to the use of antibiotics, hormones, and other chemicals that are commonly used in conventional farming practices. These chemicals can interfere with the animal’s natural physiology and can potentially lead to negative effects on nutrient absorption and utilization.
Currently Viva Raw is a company I will buy from because the meat they used has never been exposed to antibiotics. It’s interesting to note that their recipes provide adequate levels of zinc.
What About Zinc Supplements?
The bioavailability of zinc varies depending on the form in which it is consumed. In supplements, different zinc compounds have different levels of bioavailability, which refers to the proportion of zinc that is absorbed by the body and can be used for its various functions. Here’s an overview of some common zinc supplement forms and their bioavailability:
- Zinc picolinate: This form of zinc is chelated to picolinic acid, which is believed to enhance zinc absorption. Studies suggest that zinc picolinate has higher bioavailability than some other forms of zinc, making it a popular choice for supplementation.
- Zinc citrate: Zinc citrate is formed by combining zinc with citric acid. This form is considered to have good bioavailability and is another common choice for zinc supplements.
- Zinc gluconate: This is a widely used form of zinc in supplements, formed by combining zinc with gluconic acid. Zinc gluconate has moderate bioavailability and is often found in over-the-counter cold remedies and lozenges.
- Zinc sulfate: Zinc sulfate is an inorganic form of zinc that has relatively lower bioavailability compared to some other forms, such as zinc picolinate or zinc citrate. It is often used in supplements due to its low cost, but it may cause gastrointestinal side effects,
- Zinc oxide: This form of zinc is used as a supplement, but it has the lowest bioavailability among the common zinc supplement forms. Zinc oxide is more commonly used as a topical agent in sunscreens and diaper rash creams.
- Zinc glycinate: This form of zinc is chelated to the amino acid glycine, which may help improve its absorption. Zinc glycinate is considered to have good bioavailability, although fewer studies have been conducted on this form compared to other forms of zinc.
It is essential to note that individual factors, such as the dog’s overall health, diet, and genetics, can influence zinc absorption from supplements. Additionally, the presence of other nutrients or compounds in the diet, such as phytates or oxalates, can impact the bioavailability of zinc.
What Is The Biocellular Pathway to Zinc?
Zinc is an essential trace element involved in numerous biochemical processes within the body. The biocellular pathway of zinc can be broken down into several stages: ingestion, absorption, transport, storage, utilization, and excretion. Here’s a brief overview of these stages:
- Ingestion: Zinc is obtained from the diet through food sources or supplements. Animal-based foods like meat and fish, generally provide a more bioavailable form of zinc compared to plant-based foods. For example, seeds do not provide enough zinc to meet the daily allowances in a reasonably sized portion.
- Absorption: Zinc absorption primarily takes place in the small intestine, particularly in the duodenum and jejunum. Zinc uptake is facilitated by specific transporters such as Zip4 (SLC39A4) on the apical membrane of enterocytes (intestinal cells). Zinc absorption is a saturable, concentration-dependent process that can be influenced by various factors like the presence of other nutrients or the type of zinc compound.
- Transport: Once absorbed, zinc binds to proteins in the bloodstream, primarily albumin and alpha-2 macroglobulin, for transport to various tissues and organs. Some zinc is also loosely bound to amino acids like histidine and cysteine, forming low-molecular-weight complexes.
- Storage: The body stores zinc in various tissues, including bone, muscle, skin, and the liver. Metallothioneins, a family of cysteine-rich proteins, play a significant role in intracellular zinc storage and regulation.
- Utilization: Zinc is a cofactor for over 300 enzymes and plays a critical role in various cellular processes, including DNA synthesis, gene expression, immune function, wound healing, and growth and development. It is also involved in the structure and function of many proteins, such as zinc-finger transcription factors, which regulate gene expression.
- Excretion: The body excretes excess zinc primarily through feces, urine, and sweat. The kidneys play a significant role in regulating zinc homeostasis by filtering and reabsorbing zinc as needed.
Overall, zinc homeostasis in the dog’s body is a complex process involving multiple regulatory mechanisms to maintain an adequate balance between zinc absorption, utilization, and excretion.
How Can I Tell If My Dog is Zinc Deficient?
Zinc deficiency in dogs can lead to various health issues and symptoms, as zinc plays a vital role in numerous physiological processes. Some of the signs and consequences of zinc deficiency in dogs include:
- Skin issues: One of the most common symptoms of zinc deficiency in dogs is skin problems, such as dermatitis, hair loss, and poor coat quality. Zinc plays a crucial role in maintaining healthy skin and hair. Often times a dog will have hard calloused elbows or fur loss around the eyes when they are zinc deficient.
- Growth retardation: Zinc deficiency can affect a dog’s growth, especially in puppies. Adequate zinc levels are necessary for proper growth and development. Large breed dogs have to be carefully monitored as well.
- Immune system dysfunction: Zinc plays a vital role in maintaining a healthy immune system. A deficiency can result in a weakened immune system, making the dog more susceptible to infections and illnesses.
- Reproductive problems: Zinc is essential for reproductive health in both male and female dogs. A deficiency can lead to fertility issues, such as reduced sperm quality in males and poor reproductive performance in females.
- Delayed wound healing: Zinc is involved in the wound healing process, and a deficiency can result in slow or incomplete healing of injuries.
- Behavioral changes: In some cases, zinc deficiency may contribute to behavioral changes, such as increased irritability or lethargy.
How Can I Tell If My Dog Ate Too Much Zinc?
Zinc toxicity, also known as zinc poisoning, can occur in dogs when they consume excessive amounts of zinc, typically from ingesting objects containing zinc, such as coins, metal screws, or zinc oxide ointments. Over-supplementation of zinc in their diet can also lead to zinc toxicity, although this is less common.
Some of the signs and symptoms of zinc toxicity in dogs include:
- Vomiting and diarrhea: One of the first signs of zinc toxicity is gastrointestinal upset, which may include vomiting, diarrhea, and abdominal pain. Interestingly enough, I stopped feeding zinc when I had 3 out 5 of my clients at that time reporting their dogs threw up when they ate oysters.
- Anorexia and weight loss: Dogs suffering from zinc toxicity may lose their appetite and experience significant weight loss.
- Lethargy and weakness: Affected dogs may become weak, lethargic, and show a lack of energy or interest in their normal activities.
- Hemolytic anemia: Excess zinc can damage red blood cells, causing them to rupture and leading to hemolytic anemia. This can result in pale gums, rapid breathing, increased heart rate, and jaundice (yellowing of the skin, gums, and whites of the eyes).
- Kidney and liver damage: Prolonged or severe zinc toxicity can cause damage to the kidneys and liver, leading to kidney failure or liver dysfunction.
- Neurological symptoms: In severe cases, zinc toxicity can cause neurological symptoms, such as ataxia (uncoordinated movements), seizures, or even coma.
How Much Zinc Do Dogs Need?
The Association of American Feed Control Officials (AAFCO) has established minimum and maximum requirements for zinc in dog food.
- Adult dogs: The AAFCO minimum requirement for adult dogs is 120 mg/kg of dry matter (DM) in complete and balanced diets. The AAFCO maximum safe level for zinc in dog food is 1000 mg/kg of DM.
- Growing puppies: The minimum requirement for growing puppies is 150 mg/kg of DM.
I use Animal Diet Formulator for formulating recipes that are tied to AAFCO’s standards. That said, other nutrition programs are tied to NRC.
The National Research Council (NRC) has established minimum and maximum requirements for zinc in dogs based on their age, breed, size, and physiological needs. The NRC recommends the following minimum and maximum allowances for zinc:
- Adult dogs: The recommended minimum allowance for zinc is 30 mg/kg of dry matter (DM) for adult dogs, and the maximum safe allowance is 200 mg/kg DM.
- Growing puppies: The recommended minimum allowance for zinc is 45 mg/kg of DM for growing puppies, and the maximum safe allowance is 400 mg/kg DM.
Copper and Zinc Ratio For Dogs
The ideal ratio of zinc to copper in a dog’s diet is not universally fixed, as it can vary depending on factors such as the dog’s age, breed, size, and overall health. However, some general guidelines can help ensure a balanced intake of these essential trace minerals.
A commonly suggested zinc-to-copper ratio in a dog’s diet is around 10:1 to 15:1. However, this ratio can vary based on the individual dog’s needs and the specific diet being fed. It is important to remember that the bioavailability of both zinc and copper can be influenced by the presence of other nutrients and dietary factors. For example, high levels of zinc can interfere with copper absorption, and vice versa.
There is recently more talk about copper storage disease and the high amount of copper in the organs we feed our dogs. This is still an area that is of great discussion and something I am watching closely.
I have had clients come to me from commercially fed diets where the dog was diagnosed with copper storage disease. It’s not an easy diagnosis since it can cost upwards of $5,000 for the test. But a dog’s high liver counts in the blood test might be the first indication to examine this further. I shall have to do another article as copper storage deserves its own deep dive.
What Markers Show My Dog Is Getting Enough Zinc?
- Coat and skin health: Zinc plays a critical role in maintaining healthy skin and coat in dogs. A dog with a healthy coat and skin is likely to receive adequate amounts of zinc in their diet.
- Appetite: Zinc deficiency can lead to a loss of appetite in dogs, so a healthy appetite can be an indication that the dog is receiving adequate amounts of zinc.
- Immune function: Zinc is essential for immune function in dogs, and a healthy immune system can indicate that a dog is receiving enough zinc in their diet.
- Growth and development: Adequate zinc intake is crucial for proper growth and development in puppies, so appropriate growth and development milestones can indicate that a puppy is receiving adequate amounts of zinc in their diet.
- Blood tests: A blood test can measure the level of zinc in a dog’s blood, and low levels may indicate a zinc deficiency. However, blood tests may not always be accurate indicators of zinc status, as zinc is primarily stored in tissues rather than the bloodstream.
What’s The Preferred Way To Provide Zinc?
My preferred way to ensure a dog receives adequate amounts of zinc in their diet is through high-quality meat sources, such as beef, lamb, chicken, or pork.
Working with a supplier like Viva Raw or any other company that can provide their nutritional data sheets to show how much zinc is in the food is ideal.
For those that do DIY, the nutritional content of meat can vary significantly depending on factors such as the animal’s diet, living conditions, age, breed, and processing methods. While the United States Department of Agriculture (USDA) provides guidelines for nutrient levels in meat, these levels may not accurately reflect the actual nutrient content of individual meat sources.
Unless we send in the meat we bought for testing, we really are working on ideas of how much zinc is in meat. For example, the meat that I buy from different grocery stores may vary in zinc content vs. what I think it has based on what is in my program Animal Diet Formulator as that cut of meat that provides the information is different from what I bring home.
Unfortunately, since I don’t use oysters (see this article for my reasons why) Oysters while they present with a high level of zinc are not meant to be eaten or fed every single day. Even the team at Animal Diet Formulator has noticed the wide range of zinc in oysters depending on where it is from.
In Chinese Medicine, oysters are contraindicated for skin conditions.
There is a risk of heavy metal poisoning from too many oysters. I once mentioned to a client to try to eat the same amount of oysters fed to the dog for 120 days to see what effect it might provide on their body.
I still utilize zinc supplements and start off with a goal to have it as close to a 10:1 ratio as it relates to the zinc-to-copper ratio but if a dog has skin issues when I may formulate up to 15:1 ratio.
Dogs need zinc in their diets. Kibble has this formulated into it but for those that are buying commercial or making their own dog food we need to play a closer look into the amount of zinc and copper in their diets.
Unfortunately, when it comes to raw or cooked diets, studies are lacking as to the exact allowances, and for those that are feeding these types of meals, we are still basing our formulas on AAFCO or NRC’s standards which are based on kibble studies.
Unintended imbalance in the concentration of these metals can lead to deficiency or overload disorders in zinc or copper and we haven’t even talked about how calcium affects zinc absorption.
Purists in the raw feeding world will say “balance over time” and to always feed from real food sources and while this sounds ideal in concept, the reality is we see dogs fed this way with their own host of issues that include kidney disease, liver disease, and copper storage disease to name a few.
The reality is we are still learning what is ideal because each dog will absorb these trace elements differently.
So where does that lead us?
Ideally, your dog receives this vital trace element from food, but when that isn’t an option then zinc supplementation is key.
Every dog is different due to age, lifestyle, diet, breed, and activities. Work with your vet to determine what keeps them at the optimal level of health. Get bloodwork done every six months so that you can monitor how they are doing on the food they are eating.
As always, thank you for stopping by. I wish you and your dogs good health.
White SD, Bourdeau P, Rosychuk RA, Cohen B, Bonenberger T, Fieseler KV, Ihrke P, Chapman PL, Schultheiss P, Zur G, Cannon A, Outerbridge C. Zinc-responsive dermatosis in dogs: 41 cases and literature review. Vet Dermatol. 2001 Apr;12(2):101-9. doi: 10.1046/j.1365-3164.2001.00233.x. PMID: 11360336.
Colombini S. Canine zinc-responsive dermatosis. Vet Clin North Am Small Anim Pract. 1999 Nov;29(6):1373-83. doi: 10.1016/s0195-5616(99)50133-2. PMID: 10563006.
Astudillol LR, Yen IC, Bekele I. Heavy metals in sediments, mussels and oysters from Trinidad and Venezuela. Rev Biol Trop. 2005 May;53 Suppl 1:41-53. PMID: 17465143.
Pereira AM, Maia MRG, Fonseca AJM, Cabrita ARJ. Zinc in Dog Nutrition, Health and Disease: A Review. Animals (Basel). 2021 Apr 1;11(4):978. doi: 10.3390/ani11040978. PMID: 33915721; PMCID: PMC8066201.
Pereira AM, Maia MRG, Pinna C, Biagi G, Matos E, Segundo MA, Fonseca AJM, Cabrita ARJ. Effects of Zinc Source and Enzyme Addition on the Fecal Microbiota of Dogs. Front Microbiol. 2021 Oct 13;12:688392. doi: 10.3389/fmicb.2021.688392. PMID: 34721312; PMCID: PMC8549731.
Cummings JE, Kovacic JP. The ubiquitous role of zinc in health and disease. J Vet Emerg Crit Care (San Antonio). 2009 Jun;19(3):215-40. doi: 10.1111/j.1476-4431.2009.00418.x. PMID: 19691507.
Li H, Malyar RM, Zhai N, Wang H, Liu K, Liu D, Pan C, Gan F, Huang K, Miao J, Chen X. Zinc supplementation alleviates OTA-induced oxidative stress and apoptosis in MDCK cells by up-regulating metallothioneins. Life Sci. 2019 Oct 1;234:116735. doi: 10.1016/j.lfs.2019.116735. Epub 2019 Aug 5. PMID: 31394124.
Adamama-Moraitou K, Rallis T, Papasteriadis A, Roubies N, Kaldrimidou H. Iron, zinc, and copper concentration in serum, various organs, and hair of dogs with experimentally induced exocrine pancreatic insufficiency. Dig Dis Sci. 2001 Jul;46(7):1444-57. doi: 10.1023/a:1010635820071. PMID: 11478496.
Brewer GJ, Dick RD, Schall W, Yuzbasiyan-Gurkan V, Mullaney TP, Pace C, Lindgren J, Thomas M, Padgett G. Use of zinc acetate to treat copper toxicosis in dogs. J Am Vet Med Assoc. 1992 Aug 15;201(4):564-8. PMID: 1517130.
Dirksen K, Fieten H. Canine Copper-Associated Hepatitis. Vet Clin North Am Small Anim Pract. 2017 May;47(3):631-644. doi: 10.1016/j.cvsm.2016.11.011. Epub 2017 Jan 5. PMID: 28063745.
NRC. Nutrient Requirements of Dogs; The National Academies Press: Washington, DC, USA, 1962. [Google Scholar]
Ozpinar H, Abas, Bilal T, Demirel G. Investigation of excretion and absorption of different zinc salts in puppies. Lab Anim. 2001 Jul;35(3):282-7. doi: 10.1258/0023677011911615. PMID: 11459415.
Lowe, J.A.; Wiseman, J. A comparison of the bioavailability of three dietary zinc sources using four different physiologic parameters in dogs. J. Nutr. 1998, 128, 2809S–2811S
Lowe JA, Wiseman J, Cole DJ. Zinc source influences zinc retention in hair and hair growth in the dog. J Nutr. 1994 Dec;124(12 Suppl):2575S-2576S. doi: 10.1093/jn/124.suppl_12.2575S. PMID: 7996241.
Naveh Y, Bentur L, Diamond E. Site of zinc absorption in dog small intestine. J Nutr. 1988 Jan;118(1):61-4. doi: 10.1093/jn/118.1.61. PMID: 3335940.
Nishito Y, Kambe T. Absorption Mechanisms of Iron, Copper, and Zinc: An Overview. J Nutr Sci Vitaminol (Tokyo). 2018;64(1):1-7. doi: 10.3177/jnsv.64.1. PMID: 29491267.
Pedrinelli, V., Zafalon, R.V.A., Rodrigues, R.B.A. et al. Concentrations of macronutrients, minerals and heavy metals in home-prepared diets for adult dogs and cats. Sci Rep 9, 13058 (2019). https://doi.org/10.1038/s41598-019-49087-z
Rahimi Niyyat, M.; Azizzadeh, M.; Khoshnegah, J. Effect of supplementation with omega-3 fatty acids, magnesium, and zinc on canine behavioral disorders: Results of a pilot study. Top. Companion Anim. Med. 2018, 33, 150–155.
Brewer GJ, Dick RD, Schall W, et al. Use of zinc acetate to treat copper toxicosis in dogs. Journal of the American Veterinary Medical Association. 1992 Aug;201(4):564-568. PMID: 1517130.
Blundell R, Adam F. Haemolytic anaemia and acute pancreatitis associated with zinc toxicosis in a dog. Vet Rec. 2013 Jan 5;172(1):17. doi: 10.1136/vr.100376. Epub 2012 Nov 23. PMID: 23180148.
Lee, Y.R.; Kang, M.H.; Park, H.M. Treatment of zinc toxicosis in a dog with chelation using d-penicillamine. J. Vet. Emerg. Crit. Care. 2016, 26, 825–830.
Hannah Zulueta obtained her Certificate in Canine Nutrition from CASI Institute. She is also studying for her Doctorate in Acupuncture, Traditional Chinese Medicine, and Herbalism from the esteemed Pacific College of Health and Medicine.
She resides in San Diego with her three dogs, Maggie, Orbit, and Mr. Higgins.