It is a recognized fact that all-seed diets, which are not only high in fat, but deficient in many essential nutrients, predispose psittacine birds to fatty liver degeneration. It would seem that the prevalence of this condition in all companion birds, including cockatiels, would be decreasing since the advent of pelleted diets, but this does not appear to be happening. Is this because we cockatiel breeders do not recognize this condition when it appears and kills our birds? Is it because we don’t know enough about what causes the disease? Is it because we don’t generally recognize the benefits of pellets? Is it because, in our pursuit of "substance" in show birds, we don’t differentiate between a bird with a large frame and one that is fat?
In this article, I will share some research I’ve done into this health problem. My source is AVIAN MEDICINE: Principles and Applications, by Ritchie, Harrison and Harrison. When quotes from this tome appear, they will be "italicized and appear within quotation marks, like this". This research was prompted by the diagnosis of fatty liver syndrome in two of my breeding birds and their eventual death. Both these birds had been bred by (different) prominent breeders and had been in my possession no more than a year when they died. Also, I have wondered for a long time if all our show judges could tell the difference, just by looking, between a bird of true "substance" and one that is simply fat. If they can – great! If they can’t reliably do so, then our own show standards have probably been contributing to this health problem. I understand that ACS’s judging emphasis has now been shifted to length. This is a change for the better, as a long, well-proportioned bird is less likely to be fat than a bird selected largely on the basis of "substance".
The main symptom that brought the problem to my attention was a substantial decline in weight, although I did not notice a change in eating habits. As all my birds are kept in large flights when not breeding, I did not notice this until I removed the birds from the flight in order to set them up for breeding. (Foods present in the flight cages are: pellets at all times, seed three times a week, and cooked grain and vegetable "soft food" 3 times a week.) At that time, their weight loss led me to take them to the doctor, where blood tests revealed liver problems. Although I did medicate both birds, and tried very hard to get them to eat a healthier diet in order to possibly reverse the course of this disease, they both died within two months of diagnosis. Necropsy did confirm the cause of death as fatty degeneration and failure of the liver.
At this point, I got alarmed about the possibility that my best breeding cockatiel, Dolly, (a 1996 hatched bird that is a Grand Champion in both ACS and NCS) who weighs about 200 grams at her peak weight and when "resting" and between 160 and 175 grams when raising young, might be in danger of developing this problem. I asked my vet to do blood tests in order to check out lipid (fat) levels in Dolly’s blood and also liver function. Fortunately, all these were within normal limits. This does not mean that Dolly is home free, though, as my vet informed me that, by the time tests show its presence, fatty liver degeneration is generally irreversible. This bird, however, was hatched in my aviary and learned to like her pellets and soft food when she was weaning, so I am optimistic about her healthy future.
"In zoological collections, Psittaciformes show a high prevalence of fatty infiltration of the liver. Hepatic steatosis, hepatic lipidosis and fatty degeneration have all been used to describe the condition. It has been well established that an unbalanced diet (biotin, choline and methionine deficiencies) or excessive consumption of high-energy diets with restricted exercise may lead to fatty degeneration." In other words, a diet that is high in fat and low in essential nutrients, as all-seed diets are, may lead to fatty degeneration of the liver.
Regarding treatment of the problem, …"the single most important treatment seems to be the administration of a well balanced diet free of hepatoxins. Moldy foods and seed-based diets…should be avoided. The use of lactulose, hemicellulose and supportive care including IV fluids and assisted feeding are indicated…"
Just eliminating all sources of fat from the diet won’t do the job, either, as our birds need, indeed require, the essential fatty acids, linoleic and arachidonic acid."Deficiencies of linoleic acid may be associated with decreased metabolic efficiency, decreased growth, …increased fat storage, decreased reproduction, embryonic mortality and decreased hatchability…In addition to fatty liver, excessive levels of fat in the diet are known to cause obesity, diarrhea and oily feather texture, and to interfere with the absorption of other nutrients such as calcium. Paradoxically, lack of fatty acids can also result in fatty liver infiltration because essential fatty acids are needed for lipid metabolism. Poor growth and reduced resistance to disease also occur with essential fatty acid deficiencies… If fats become rancid, essential fatty acids may be destroyed, amino acid availability may be reduced and peroxidases may be produced that interfere with the activities of fat and water soluble vitamins (biotin). Rancid foods have been shown to reduce growth and egg production in poultry….Soybean oil is a good source of fatty acids that is less likely to spoil"….Adequate levels of choline chloride have been found to help protect Anseriformes (ducks) from fatty liver infiltration of the liver".
Are we confused enough yet about how to provide a diet that won’t lead to fatty liver in our cockatiels and yet will provide the necessary nutrients for proper growth and reproduction? The obvious answer, to me, is that we cannot possibly supply the necessary nutrients, in the proper balance so that all can be utilized within our birds’ bodies, in an all-seed diet, even with vitamin, mineral and or other supplementation. Also, some supplements used by some breeders, such as "Calf Manna", a milk replacement product for calves, and/or poultry feed products, contain much too high a level of some nutrients, to the point where they can adversely affect the health of our cockatiels. A formulated product, designed by a scientific process to be properly balanced, can make our jobs as breeders much easier and result in better health in our birds. We cockatiel breeders are lucky, in that Tom Roudybush, while at the University of California at Davis, did actual experiments and long-term feeding trials with cockatiels, so our favorite birds’ dietary requirements have been established with reasonable certainty. Many pellet manufacturers are also conducting long term feeding trials so that their product can be adjusted until it is just right. All in all, I think it just makes sense to feed pellets especially designed for our companion birds.
If you think your birds won’t eat pellets, you are wrong. I’ve tried all different ways to convert birds to pellets and the one that has worked the best is this:
Give pellets and other healthy food such as vegetables and other "soft food" in the morning. Put a dish with the usual quantity of your birds’ favorite seeds in their cage for a two-hour period of time in the late afternoon or evening. Believe me, your cockatiels can eat enough seeds in 2 hours to keep them alive. They will eventually get tired of being hungry all day, though, and will begin to eat their pellets. When you see that happen, cut the time the seed is in the cage to one hour for a couple of weeks, then one-half hour for a couple of weeks, etc. Within six weeks, you could eliminate seed entirely or just limit seed to two days on the weekends, or 3 days, or whatever you think provides the proper balance. I do believe that cockatiels need some seed, but do use a seed mixture fortified with vitamins and minerals, etc. and make sure they eat it all before they get more. When they only get seed three days a week, believe me, they eat every little grain and pellet! Make sure fresh water is always available. This is even more important for birds on a pelleted diet, as pellets have a much lower moisture content than seeds.
Your birds will feel better with a better diet – and so will you!