By Susanne Russo
The following is taken from Avian Medicine: Principles and Applications, pages 786-787 I have added and modified some of the info from the book, from past personal experiences. The listing below can be used as a checklist and/or guidelines to help determine the possible source of any problems you or the pair are experiencing.
Table 29.5 Causes of Infertility
Behavioral
Immaturity
Pair incompatibility
Normal interaction between mates
Compatibility in nesting and clutch duties
Sexual inexperience
Lack of social interaction
Aviary disturbances
Excess social interaction
Homosexual pairs
Lack of pair bonding
Asynchronous breeding condition
Improper imprinting
Infrequent mating
Environmental
Incorrect photoperiod
Incorrect nest box design
Incorrect bedding in nest box
Incorrect enclosure/caging design
Lack of visual barriers
Excessive rain
Insufficient rain
Temperature
Humidity
Availability of correct foods
Loose or incorrect perches
Medical
Obesity
Age (young or old breeders)
Inbreeding, contributing to lethal and semi-lethal genes
Vent feathers
Drug therapy (causing vitamin deficiency or direct decreased fertility)
Previous hormonal therapy (testosterone injections)
Musculoskeletal
Neuromuscular Disease(contributing to pain, paresis, ataxia, weakness, decreased muscle tone or in-coordination)
Neurological Disease (paresis, Ataxia, lack of muscle control)
Seizures
Reproductive tract disease
Nutritional deficiencies or excesses
Systemic disease
Parasitic disease
Disease leading to malnutrition
Malnutrition
Cloacal abnormalities
Abnormal cloacal pH
Thyroid deficiency
Toxins (pesticides, chemicals, mycotoxins, aflatoxins)
Table 29.6 Causes of Death or Abnormalities in Embryos
FIRST TRIMESTER
Egg handling: such as storage and using an incubator
Eggs stored too long
Eggs stored under incorrect condition
Incorrect egg fumigation or sanitation
Excessive vibrations
Rapid temperature changes
High temperatures during early incubation
Incubator faults: Temperature, humidity, turning, cooling after development has begun, suffocation due to incorrect ventilation
Other contributors:
Inbreeding
Chromosome abnormalities
Egg-transmitted infectious diseases
Parental nutritional deficiencies or excess
Abnormal or aged sperm
Idiopathic developmental abnormalities
Drugs, toxins, pesticides
Cracked eggs
Small holes in eggs
SECOND TRIMESTER
Parental nutitional defeciencies:
Riboflavin
Vitamin B12
Folic acid
Biotin
Manganese
Pyridoxine
Pantothenic acid
Phosphorus
Boron
Linoleum acid
Vitamin K
Vitamin D3
Secondary vitamin deficiencies
Antibiotic therapy destroying vitamin-producing bacteria
Diet imbalances and inadequate food intake
Other contibutors:
Viral diseases
Bacterial infections
Fungal infections
Egg jarring or shaking in first trimester
Incubator faults
Inbreeding resulting in lethal genes
THIRD TRIMESTER
Malpositions:
Inadequate or incorrect turning
Outside environmental factors and humidity
Haphazard incubation
Incubator faults:
Poor incubator ventilation
Egg cooling early in incubation
Inadequate or incorrect turning
Incorrect temperature
Incorrect humidity
Long storage time pre-incubation
Other contributors:
Infectious diseases
Nutritional deficiencies: A,D, E, K, antithetic acid, folic acid
Lethal genes
Chromosomal abnormalities
Idiopathic developmental abnormalities
Note: Brewers Yeast contains many of the nutrients listed above and would be an excellent supplement to offer the birds on a regular (1-2 times a week) basis prior to breeding. In addition, sunflower takes the bad rap as a contributor to liver problems, when in fact the Striped Sunflower seed is a powerhouse of nutrients. that are essential to a healthy egg and embryo.
