Tuna and Cats: Nutritional Facts

Nutrient/165 gram can	Tuna, light, canned in water	AAFCO Nutrient Profiles for Adult Cats	Nutrient Level
Energy	191.4 kcal	45-65 kcal/kg BW	Acceptable
Protein	22 g/100 kcal	6.5 g/100 kcal	Excessive
Taurine	681 mg/kg/diet as fed (avg)	2000 mg/kg/diet as fed	Deficient
1. Taurine deficiency in the cat results in Feline Central Retinal Degeneration (FCRD). When taurine is deficient, the photoreceptor cell membranes become disrupted and dysfunctional, which eventually leads to cellular death and the loss of cells. Complete blindness ensues with full degeneration of the retina and attenuation of retinal vessels. Structural changes within the retina are permanent. 2. Taurine deficiency in the cat also results in the development of dilated cardiomyopathy (DCM). This degenerative disease causes decreased myocardial contractility, which eventually leads to cardiac failure. 3. Taurine deficiency adversely affects the cat's immune response against infectious organisms (viruses, bacteria, parasites) and malignant and metastatic disease.
Phosphorus	141 mg/100 kcal	125 mg/100 kcal	Excessive
Excess phosphorus can result in bone loss, uroliths, decreased weight gain, decreased feed intake, calcification of soft tissues, secondary hyperparathyroidism. Levels of phosphorus exceeding 0.6% (DMB) are associated with lower plasma phosphorus concentrations, reduced creatinine clearance and decreased magnesium absorption. Continued feeding of high levels of dietary phosphorus may be detrimental to renal function.
Calcium	9.5 mg/100 kcal	150 mg/100 kcal	Deficient
Inadequate calcium intake produces hypocalcemia, which stimulates release of PTH, which in turn stimulates production of 1,25-dihydroxycholecalciferol, resulting in a higher fractional absorption of calcium and phosphate, and lower calcium but higher phosphate concentration in urine. PTH acts with vitamin D to promote bone resorption and turnover, which may lead to pathologic fractures.
Calcium-to-Phosphorus Ratio	1:14.8	1:1	Excessive
A food grossly deficient in calcium, but adequate in phosphorus can cause secondary hyperparathyroidism.
Iron	1.32 mg/100 kcal	2 mg/100 kcals	Deficient
Iron is essential for the production of hemoglobin, the oxygen-carrying component of red blood cells. Iron deciciency can result in anemia, anorexia, weight loss, decreased serum albumin concentrations, hepatic dysfunction, and hemosiderosis.
Sodium	293.5 mg/100 kcal	50 mg/100 kcal	Excessive
Excess sodium and chloride can cause excessive thirst, puritis, constipation, seizures and death. Cats with decreased renal function can only vary sodium excretion over a limited range, which narrows progressively as GFR declines. Thus, cats with renal failure cannot tolerate excessively high or low dietary sodium intake levels. If excessive sodium is ingested, sodium retention with expansion of extracellular fluid volume can occur and produce or worsen pre-existing hypertension, fluid overload and edema.
Magnesium	23 mg/100 kcal	10 mg/100 kcal	Excessive
Excess magnesium can result flaccid paralysis and in struvite crystalluria and urolithiasis in neutral to alkaline urine.
Zinc	.63 mg/100 kcal	1.9 mg/100 kcal	Deficient
Zinc deficiency adversely affects a number of diverse physiologic functions. Some of zinc's primary functions include: 1) nucleic acid metabolism, 2) protein synthesis, 3) carbohydrate metabolism, 4) immunocompetence, 5) skin and wound healing, 6) cell replication and differentiation, 7) growth and 8) reproduction. Zinc deficiency results in anorexia, decreased growth rate, alopecia, parakeratosis, impaired reproduction, depressed immune function and growth disorders of the skeleton.
Vitamin A	92 IU/100 kcal	125 IU/100 kcal	Deficient
Vitamin A deficiency results in ocular lesions nyctalopia (night blindness) and xerophthalmia (extreme dryness of the conjunctiva). Other signs include anorexia, weight loss, ataxia, skin lesions, increased susceptibility to infection, retinal degeneration, poor coat, weakness, increased cerebrospinal fluid pressure, nephritis, skeletal defects (periosteal overgrowth and narrowing of foramina) and impaired reproduction.
Vitamin D	0	13 IU/100 kcal	Deficient
Signs of vitamin D deficiency are frequently confounded by a simultaneous deficiency or imbalance of calcium and phosphorus. Clinical signs generally include rickets (young animals), enlarged costochondral junctions, osteomalacia (adult animals), osteoporosis (adult animals) and decreased serum calcium and inorganic phosphorus concentrations. Clinical studies of vitamin D deficiency in cats has produced neurologic abnormalities associated with degeneration of the cervical spinal cord. Other signs included hypocalcemia, elevated PTH concentrations, posterior paralysis, ataxia and eventual quadriparesis.
Vitamin E	0.46	10.75 IU/100 kcal	Deficient
In general, the neuromuscular, vascular and reproductive systems are affected most commonlyby vitamin E deficiency. Signs of vitamin E deficiency are mostly attributed to membrane dysfunction as a result of the oxidative degradation of polyunsaturated membrane phospholipids and disruption of other critical cellular processes. In cats, vitamin E deficiency signs include immunodeficiency, dermatosis, anorexia, mypoathy, steatitis, focal interstitial myocarditis, focal myositis of skeletal muscle and periportal mononuclear infiltration in the liver.