Probable Cause Corrective Measures Improper incubation temperatures (usually too high) Follow recommended incubation temperatures. Improper egg turning Turn at least 3 times daily. Inherited low hatchability Avoid cross breeding. May need to secure different breeding stock. Improper ventilation Increase ventilation rate in incubator and/or room, but avoid drafts. Add oxygen at high altitudes. Pullorum disease or other salmonelloses Use eggs from disease-free sources. Have NPIP representatives blood-test the breeder flock. Improper nutrition of breeders Provide a well-balanced nutritional diet to breeders.

Troubleshooting: General Problems

Sign: Eggs candle clear; broken out eggs show small white-dot germinal disc; no blood. Infertile. Causes:

1. Immature males. Males may need to be photostimulated 2 weeks earlier than females.

2. Males with abnormal sperm; females with abnormal egg (germinal disc). This occurs most
    often in very young or very old breeders.

3. Too few males, resulting in infrequent mating; too many males, resulting in fighting or
    interference. Ratios of 1:12 to 1:15 for light breeds and 1:10 to 1:12 for heavy breeds are
    suggested.

4. Extreme weather conditions.

5. Old breeders. Spiking with young males may help if the problem is with the male.

6. Breeder flock disease. This is often indicated by rough, misshaped, or thin-shelled eggs.

7. Excess body weight, especially in broiler breeder males (>4,800 g, 10.6 lb).

8. Nutritional deficiencies or excesses; severe feed restriction.

9. Feet and leg problems, especially in males of heavy breeds.

10. Certain drugs, pesticides, chemicals, toxins, or mycotoxins.

11. Parasites, such as mites.

12. Inadequate floor space.

13. Decreased mating frequency, or no mating, is commonly seen in many of the
       conditions listed above; this may often be the direct cause of infertility.

14. Inadequate lighting (intensity or day length).

15. Improper artificial insemination procedures (if artificial insemination is used).