Stained eggs
Description
All or part of the egg shell may become stained by various substances, e.g. blood, faeces.
Incidence
The incidence of stained eggs varies, partly because stains may be caused by a variety of substances. Smears of blood are more common on eggs from pullets in early lay.
| Cause | Control |
|---|---|
| Blood from a prolapsed cloaca, cannibalism or vent picking | Do not allow pullets to become over-fat, as the incidence of prolapse is greater in fat birds. There should not be sudden large increases in day length as pullets come into lay. Regularly clean cage bottoms and roll-out trays. Clean belt pick-up systems. |
| Faecal contamination | Keep nest boxes supplied with clean nesting material. Maintain proper hygiene, follow effective vaccination programmes and, when necessary, use appropriate medication to keep birds free of diseases which cause enteritis. Feed should not contain high levels of ingredients causing loose or sticky droppings, such as molasses and high-tannin sorghums. |
| Water stains | Minimise roof condensation, which can drip onto eggs, by providing adequate shed ventilation. Eliminate drips from faulty misting nipples and drinker lines. |
| Sanitisers used in egg washing | Make sure that sanitisers in washing solutions are properly dissolved and used at the correct concentrations. |
| Grease and oil stains | Do not allow eggs to become contaminated by lubricants on rollers in packing systems. |
| Certain drugs produce mottled shells or white shells in breeds that normally lay brown eggs. The drug chlortetracycline produces yellow shells. | Do not feed to layers or pullets just before lay. Follow correct procedures for medication, including not feeding the medication for the required withholding time before eggs are collected, to prevent residues. |
COPYRIGHT NOTICE: OPTIMUM EGG QUALITY - A PRACTICAL APPROACH
© The State of Queensland, Australia (through its Department of Primary Industries and Fisheries) and DSM Nutritional Products Ltd., 2007. No part of this publication may be reproduced, copied or transmitted save with prior written permission of Director, Intellectual Property Commercialisation Unit, Department of Primary Industries and Fisheries, GPO Box 46 Brisbane, Queensland, Australia 4001, and DSM Nutritional Products Ltd.
© The State of Queensland, Australia (through its Department of Primary Industries and Fisheries) and DSM Nutritional Products Ltd., 2007. No part of this publication may be reproduced, copied or transmitted save with prior written permission of Director, Intellectual Property Commercialisation Unit, Department of Primary Industries and Fisheries, GPO Box 46 Brisbane, Queensland, Australia 4001, and DSM Nutritional Products Ltd.