This item is only available as the following downloads:
Jacqueline P. Jacob, Richard D. Miles and F. Ben Mather2 Parts of the egg.
Egg Quality 2 Approximate areas of the shell surface for assessing stains.
Egg Quality 3
Egg Quality 4
Egg Quality 5
Egg Quality 6 Dietary Factors: Storage of Eggs and Age of Hen:
Egg Quality 7 Measuring air cell depth.
Egg Quality 8
Egg Quality 9 Summary of standards for exterior quality of chicken eggs. Must be clean May show small specks, stains or cage marks that do not detract from general appearance of the egg May show traces of processing oil Slight stains Moderate stains: localized (single) < 1/32 of shell scattered (2 or more) < 1/16 of shell (See Figure 2 for approximate surface areas) Prominent stains Moderate stains: localized (single) >1/32 of shell scattered >1/16 of shell (see Figure 2 for approximate surface areas) NONE NONE Adhering dirt or foreign material Approximately the usual elliptical shape Unusual or decidedly misshapen (very long or distorted) May have rough areas and small calcium deposits that do not materially affect shape or strength Extremely rough areas that may be faulty in soundness or strength May have large calcium deposits May have slight ridges that do not materially affect shape or strength May have pronounced ridges Must be free from thin spots May show pronounced thin spots Causes of shell quality problems. A. Odd shaped 1. Inherited 2. Disease: Newcastle disease, infectious bronchitis, laryngotracheitis, Egg Drop Syndrome 76 3. Age of hens: incidence is higher in older hens B. Thin, porous or shell-less 1. Inheritance influences porosity and ability to produce strong shells 2. Lack of sufficient calcium, phosphorus, manganese or vitamin D3 3. Vitamin D2 mistakenly substituted for D3 4. Excess phosphorus consumption, especially by older hens 5. Ingestion of sulfanilamide (sulfa drugs) 6. Disease: Newcastle disease, infectious bronchitis, avian influenza, Egg Drop Syndrome 76 7. Hens exposed to temperature over 85-90F 8. Age of hens: incidence higher with older hens 9. Premature laying of the egg
Egg Quality 10 Causes of shell quality problems. C. Rough or abnormal shell texture 1. Inherited 2. Newcastle disease or infectious bronchitis 3. Excessive use of antibiotics 4. Excess calcium consumption by the hens 5. Copper deficiency D. Mottled shells 1. Primarily caused by high or low extremes in humidity 2. Inherited 3. Manganese deficiency 4. Artificially induced E. White strain layers producing tinted eggs 1. Primarily inherited. F. Yellow shells 1. Extended use of high levels of certain antibiotics G. Tremulous or loose air cells 1. Newcastle disease 2. Infectious bronchitis 3. Rough handling of eggs 4. Eggs stored large end down H. Depigmented brown shell 1. Infectious bronchitis 2. High stress in the flock 3. Egg Drop Syndrome 76 Summary of standards for interior quality of chicken eggs by candling. Air cell 1/8 inch or less in depth 3/16 inch or less in depth More than 3/16 inch Doesn't apply White (albumen) ClearFirm ClearMay be reasonably firm ClearMay be weak and watery Doesn't apply Yolk Outline slightly defined Outline may be fairly well-defined Outline clearly visible Doesn't apply Spots (blood or meat) None None Blood or meat spots aggregating not more than 1/8 inch in diameter Blood or meat spots aggregating more than 1/8 inch in diameter Causes of albumen (egg white) quality problems.
Egg Quality 11 Causes of albumen (egg white) quality problems. A. Increased thin white 1. Inherited 2. Diseases: Newcastle disease, infectious bronchitis, laryngotracheitis or Egg Drop Syndrome 76 3. High egg storage temperature 4. Age of hens: incidence higher with older hens 5. High level of ammonia from droppings 6. Loss of CO2 from egg 7. High vanadium levels in the feed B. Greenish albumen in fresh eggs 1. Riboflavin (vitamin B2) in feed: this is natural and is not undesirable C. Cloudy white 1. High CO2 inside egg: may result from oiling egg too soon after lay 2. Refrigeration of fresh eggs at low temperatures (32 to 39F) D. Pink white 1. Cottonseed oil (contains the fatty acids malvalic and sterculic acid) E. Blood spots 1. Inherited 2. Increased blood spots occur with sudden environmental temperature changes 3. Age of hens: incidence higher with older hens 4. Deficiencies of vitamin K (probably rare) or vitamin A 5. Sulfaquinoxaline may increase incidence if vitamin K is marginal F. Meat spots 1. Inherited 2. Bits of ovary, oviduct or cuticle 3. Blood spots dissolved from blood pigment G. Spoilage by bacteria and molds 1. Green whites (under UV light) Pseudomonas bacteria 2. Black rots caused by Proteus bacteria 3. Molds can cause either green or black appearance when candled Causes of yolk quality problems. A. Blood spots 1. Inherited 2. Increased blood spots occur with sudden environmental temperature changes 3. Age of hens: incidence higher with older hens 4. Deficiencies of vitamin K (probably rare) or vitamin A 5. Sulfaquinoxaline may increase incidence if vitamin K is marginal B. Yolk color variation 1. Pigment level in diet 2. White yolks: a. Unknown disease condition b. Capillary worms c. White corn, grain sorghum, wheat or barley in ration, without pigment supplement 3. Olive or salmon colored yolks: caused by 5 percent or more cottonseed meal containing gossypol or cyclopropene fatty acids in the diet
Egg Quality 12 Causes of yolk quality problems. C. Mottled yolks 1. Nicarbazin (anticoccidial drug) 2. Gossypol (cottonseed meal) 3. Worming compounds: piperazine, citrate, phenothiazine, dibutylin dilaurate 4. Tannic acid 5. Calcium deficiency 6. Age of hens: incidence is lower in older hens 7. Inherited 8. Storage time, increases with time D. Thick, pasty, rubbery or cheese-like yolks 1. Crude cottonseed oil 2. Severe chilling or freezing of intact egg 3. Seeds of velvetweed and other related species E. Off-odors 1. Chemicals for treating parasites 2. Fruits, vegetables, and flowers: never store in egg cooler 3. Household detergents: use only special egg washing detergent/sanitizer materials 4. Moldy flats, cases or egg room F. Flat yolks 1. Weak vitelline membrane: age of eggs, improper storage temperature, age of hens 2. Indirect effect of poor egg shell quality 3. Nicarbazin (anticoccidial drug) USDA classification of egg sizes. Jumbo 30 2.5 Extra large 27 2.2 Large 24 2.0 Medium 21 1.7 Small 18 1.5 Peewee 15 1.2