by David E Anderson, DVM, MS, Diplomate ACVS
International Camelid Institute
College of Veterinary Medicine
The Ohio State University
Congenital defects are a relatively common occurance among camelids. The high prevalence of congenital defects has been blamed on the narrow range of genetic diversity available to breeders prior to the importation of native South American stock during the 1980's. Despite the infusion of a presumably broad genetic pool from South America (primarily Peru) and rigid veterinary inspection of camelids prior to importation, congenital defects continue to be a problem for many breeders. The veterinarians role in counseling owners of camelids with congenital defects centers around the difference between congenital and heritable defects.
CONGENITAL VERSUS HERITABLE DEFECTS
Congenital refers to a trait that an animal is born with (existing at the time of birth). These defects are not neccessarily genetically programmed and may have resulted from problems encountered during organogenesis or fetal development in utero (e.g. flexural limb deformity). Also, those defects that are genetically programmed in the fetus may not have originated from "heritable" defects. Heritable defects are genetically programmed in that animal and can be passed on from the affected animal. However, there are two options for genetic defects: 1) a point mutation in that animal but not preexisting in the parents and 2) a genetic defect carried by one or both parents and transmitted to the offspring.
| DEFECT | HERITABLE ? | RECOMMENDATION | |
| Musculoskeletal | Maxilofacial dysgenesis (wry-face) |
Unknown - possibly abnormal in-utero positioning | not use offspring; not repeat parentage combination |
| Angular limb deformity | Unknown - often aquired | usually used for breeding | |
| Flexural limb deformity | Unknown - possibly in utero malpositioning | usually used for breeding | |
| Tarsocrural dysgenesis | Unknown | not use offspring; not repeat parentage combination | |
| Choanal Atresia | YES - unknown mode of transmission - probably requires both parents | not use offspring; maybe not use either parents but data not complete | |
| Cardiac Defects | Transposition of Greater Vessels | Unknown | not use offspring; not repeat same parentage |
| Ventricular septal defects | Unknown - suspected | not use offspring; not repeat parentage combination |
|
| Reproductive Tract | Segmental Aplasia | Unknown - suspected | not use offspring; not repeat parentage |
| Cryptorchidism | Unknown - suspected | not use offspring; not repeat parentage |
|
| Pseudohermaphrodite | Unknown - suspected | not use offspring; not repeat parentage |
|
| Immunodeficiency Syndrome | Unknown | offspring die < 3 years |
REFERENCES
Reproduced from www.vet.ohio-state.edu/docs/ClinSci/camelid/ with permission of Dr. Anderson. Copyright © Dr. David Anderson
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