Feed pullets diets containing 3.0% of calcium (Ca) and 0.4 % of phosphorous (P) from 8 to 20 weeks of age.
Pullet feed on the 3.25% calcium (Ca) diet developed a high incidence of Urolithiasis by 18 weeks, which persisted or increased in laying period through 51 weeks of age. Low levels of dietary phosphorous during the rearing period exacerbated the effect of excess calcium
Fed pullets with excess dietary calcium, in particular if combined with low available dietary phosphorous, may cause urolithiasis. Urolithiasis is primarily seen in laying flocks and has been associated with increased mortality and decreased egg production. Urolithiasis is characterized by severe atrophy of one or both kidneys, distended ureters, and varying degrees of renal and visceral deposits.
Overall mortality in affected flocks may exceed 2% for several months, and in excess of 50% of this mortality may be due to urolithiasis.
Laying hens die suddenly and may be in good condition and full of lay or they may have a reduced muscle mass, small pale combs, and white pasting on pericloacal feathers.
The occurrence is always more severe when immature pullets are fed
- Causing Agents
- Pullet feed on the 3.25% calcium (Ca) diet and Low levels of dietary phosphorous during the rearing period exacerbated the effect of excess calcium.
- Affected Systems/Organs
- Urinatry System
- Mainly Affects
- Kidney and visceral urate deposition ("visceral gout")
- Adequate levels of Calcium and phosphorous in the pullet diets
- Suggested Actions
- Can be confirmed with clinical signs and gross lesions
- Technical assistance recommended
- Can be managed with feed additives, off-the-shelf medications
- Diagnosis should be confirmed with rapid assays and/or a certified laboratory
- Veterinary intervention is recommended
Impact on Egg quality
Impact on Liveability
Impact on Production
Overall Economic Impact
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