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A case of clubbed down syndrome in broilers.
Tommy Van Limbergen1, Stefan Ronsmans2, Dominiek Maes1
1Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Avian Pathology : Journal of the W.V.P.A
|November 4, 2020
Summary
Excessive calcium and iron in broiler breeder feed caused clubbed down syndrome in chicks due to zinc deficiency. This condition was reversible when breeder feed mineral levels were corrected.
Area of Science:
- Avian pathology
- Poultry nutrition
- Animal science
Background:
- Clubbed down syndrome (CDS) is a feather disorder affecting broiler chicks.
- Early life growth retardation is a key symptom of CDS.
Observation:
- Approximately 25% of a broiler flock exhibited severe growth retardation (45g) and feather abnormalities within the first week.
- Investigations included necropsy, histology, blood and liver analysis, serology, and PCR on broilers and breeder farms.
Findings:
- Excessive calcium and iron in broiler breeder feed, 3 weeks prior to chick manifestation, caused relative zinc deficiency in breeders and absolute zinc deficiency in hatching eggs.
- This nutritional imbalance led to clubbed down syndrome in broiler offspring.
- Astrovirus involvement was considered but not confirmed.
Implications:
- Correct mineral levels in broiler breeder feed are crucial for preventing developmental disorders in offspring.
- The study highlights the impact of maternal nutrition on broiler chick health and development.
- The observed reversibility emphasizes the importance of feed management in poultry production.
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