Ensuring that pet birds are receiving appropriate amounts of calcium, phosphorus and vitamin D is key to maintaining their health.
Pet birds need calcium, phosphorus and vitamin D in the proper ratios in order to grow healthy and stay strong throughout their lives. These nutrients work together and help with bone development and maintenance, as well as affect many systems of the body. The best way to ensure a pet bird is getting all these critical nutrients is to supply it with a varied diet that includes pellets, lots of greens and fresh food.
A calcium to phosphorus ratio of 2:1 generally works well for bird species that have sufficient vitamin D levels to allow these elements to be absorbed by the body. If the ratio is off or the bird does not have enough vitamin D, it may become deficient, which can lead to many health issues. For example, the body will begin to pull the minerals it needs out of the bones, possibly causing seizures or other problems.
While it is rare for a bird to be low in calcium, birds that are breeding or just laying eggs and certain parrot species, such as the African Grey, may require more calcium, phosphorus and vitamin D. Overweight birds and those that eat a diet high in fatty foods, such as high-fat seeds like sunflower seeds, may also have calcium deficiencies, as fat can block the absorption of calcium. Their diets should be adjusted to be lower in fat and higher in protein, and should include some calcium- and phosphorous-rich fresh greens. A diet consisting of too much cereal and vegetables that have a lot of oxalates, such as spinach and rhubarb, can negatively impact calcium absorption, as well.
On the other hand, greens such as mustard, turnip and dandelion greens as well as dark green lettuces, parsley, kale and watercress are optimal for maintaining calcium levels. Some other foods that are good secondary choices for calcium content include carrots, squash and green beans, and to a lesser extent, some fruits like apples, strawberries, blueberries and raspberries. These fresh foods also have a good to fair ratio of phosphorus in them to keep things in better balance.
Bird pellet diets, when comprising 50 to 60 percent of a bird’s diet, can be another good source of calcium, phosphorus and vitamin D. Some diets are made for specific species like the greys, as they take into account their unique need for additional calcium. No dietary supplementation is necessary if at least half of a bird’s diet consists of pellets. In fact, feeding a bird a diet that is too rich in nutrients such as calcium can cause many health problems, including hypercalcemia, gout and a decrease in appetite.
On the other hand, if birds are not eating enough pellets, then some supplements should be added to the diet. Bone meal, for example, can help supply additional calcium and phosphorus, and fish oil and eggs are a source of vitamin D. Supplements that include vitamins, amino acids and minerals can be great for birds that are not eating a highly nutritious diet.
Vitamin D is essential to regulate the absorption of calcium and phosphorus, and therefore, it must be included in the bird’s diet, whether through pellets or supplements, unless full-spectrum lighting is provided. When exposed to sufficient full-spectrum light with UV, a bird can produce its own vitamin D3, which is much more potent than supplemented vitamins. Unfortunately, sunlight coming through a window will not work, as the glass will filter the UV rays out—plus the bird can overheat if it is not able to get out of the sun. The best bet is to use full-spectrum bulbs above the bird’s cage for eight to 10 hours a day, which will allow the proper amount of calcium and phosphorus levels to be absorbed by the body.
Other well-known sources of calcium for birds are cuttlebones and mineral blocks. These should be offered to caged birds at all times—and especially when breeding. If a bird feels deficient, it will chew on the cuttlebone or mineral block to get the nutrients it needs. Cuttlebones and mineral blocks are also beneficial in keeping birds’ constantly growing bills in good shape.
Cuttlebones are usually offered to smaller species such as finches, parakeets, cockatiels, lovebirds and other small parrots. Large parrots such as conures, greys, amazons, cockatoos and macaws are given larger and tougher mineral blocks to chew on, as they can destroy a cuttlebone too quickly.
Lastly, keep in mind that birds that are breeding should be offered more protein and supplements with calcium, phosphorus and vitamin D, so they will have plenty of minerals to make eggshells. PB
Robyn Bright has a master’s degree in parrot biology and more than 35 years of pet retailing experience.