Gout In Poultry

Gout is a metabolic disease characterized by deposition of urates on the surfaces of various internal

organs, or various joints. It is a very common finding during postmortem examination of poultry, and

can be a source of great economic loss to the farmer. Birds usually die from kidney failure. Both in

broiler and layer chicks, gout can be seen from 4th day onward and can be a serious problem between
2nd and 3rd week. In layers, though relatively rare, gout can be seen even up to SOth week, and is mostly of nutritional origin (see 'urolithiasis). Gout occurs in two forms: I. Visceral, and 2. Articular.

Causes

I. Lack of water, or inadequate supply of water (dehydration).

2. Inadequate number of drinkers, or even just overcrowding.

3. Excess of dietary calcium, or calcium:phosphorus imbalance, or low intake of phosphorus in relation to calcium.

4. Increased intake of protein.

5. Vitamin A deficiency.

6. Excessive amount of salt (sodium chloride).

7. Infection with certain kidney damaging strains of infectious bronchitis virus in young chickens.

8. Fungal toxins (mycotoxins), such as oosporein and ochratoxin.

9. An electrolyte excess or deficiency.

10. Treatment with sodium bicarbonate.

Postmortem Findings

I. Presence of white chalky deposits on the surfaces of heart, liver, kidneys, proventriculus, and lungs. These

deposits are seen as white chalky coating (Fig. I 14, I IS).

2. The chalky deposits first begin on the heart and then spread (Fig. I 16, I 17).

3. Kidneys are swollen, congested, and typically gouty (greyish white in colour) (see Fig. 121).

4. One or both ureters may be distended with white material.

S. In the articular gout, when joints are opened, the tissue surrounding the joints is white due to urate

deposition (Fig. I 18).

Diagnosis

Can be done easily from the typical postmortem findings.

Treatment and prevention

I . Give plenty of water containing electrolytes. Make sure that there are at least 30 drinkers per 1000 birds.Correct overcrowding, if any.

2. Reduce the high level of protein, increase maize, and formulate the feed accordingly for a few days to get over the problem.

3. In the laying hens, avoid feeding high levels of calcium before sexual maturity. No more than I % calcium should be fed to Leghorn birds before maturity.

4. Use urine acidifiers, such as methionine hydroxyl analogue (MHA), or even supplemental DL-methionine.