The Rough and Smooth Collie are a relatively healthy breed free from natural unexaggerated form which has protected it from many of the inherited conditions which plague some other breeds. 

However like all breeds it is susceptible to a few inherited conditions, which responsible breeders endeavour to minimize as much as possible by the careful monitoring and selection of breeding stock.


Many herding breed dogs (the most commonly affected in the UK are: All breeds of Collie, Shetland Sheepdog, GSD and, Australian Shepherd dogs - including cross breeds) have a genetic predisposition to adverse drug reactions involving over a dozen different drugs.

The most serious adverse drug reactions involve several antiparasitic agents, Ivermectin, Milbemycin (and related drugs), the antidiarrheal agent Loperamide (Imodium), and several anticancer drugs (Vincristine, and Doxorubicin, plus several others). These drug sensitivities result from a mutation in the multidrug resistance gene (MDR1 gene).



Class A DO NOT use these drugs in dogs with the MDR1 Gene Defect

Ivermectine substances "Anti parasites": (Diapec®, Ecomectin®, Equimax®, Eqvalan®, Ivomec®, Noromectin®, Paramectin®, Qualimec®, Sumex®, Virbamec®) 

Doramectine substances "Anti parasites":  (Dectomax® )

Loperamide substances "ant diarrheal ": (Imodium®)

Moxidectine substances "Anti Parasites" (Cydectin®, Equest®) 

(Flagyl )

Class B

Use only under close control of veterinarian

Cytostatics  "Chemotherapy": (Vinblastine, Vincristine, Doxorubicine, Paclitaxel, Docetaxel, Methotrexat, Vincristine)

Immunosuppressive: (Cyclosporine A)

Heart glycosides: (Digoxine, Methyldigoxine)

Opioids: (Morphium)

Antiarrhythmics: (Verapamil, Diltiazem, Chinidine)

Antiemetics (Ondansetron, Domperidon, Metoclopramide )

Antibiotics (Sparfloxacin, Grepafloxacin, Erythromycin)

Antihistamin (Ebastin)

Glucocorticoid (Dexamethason)

Acepromazine (tranquilizer and pre-anesthetic agent) *

Butorphanol "analgesic and pre-anesthetic agent" *

Other drugs: Etoposide, Mitoxantrone, Ondansetron, Paclitaxel, Rifampicin 

Class C Can be used only in the permitted application form and dose Selamectin (Stronghold®), Milbemax®  and Advocate® .

For more details on MDR1 - together with pdf downloads - please see here



Usually referred to as CEA is a non-progressive congenital hereditory condition of the eye,which affects several breeds from the wider Collie family. Although the mode of inheritance is no longer as clear as it once was supposed, in its milder forms it does not appear to affect sight.

As there are, at present, no known genetically clear Rough Collie in this country, the only method of ensuring any puppies are clear or only mildly affected by CEA is to have the whole litter eye tested by a BVA listed opthalmologist, at the age of 6 to 7 weeks.

A list of BVA opthalmologists can be found here


Commonly referred to as PRA, either Central or Generalised, is a progressive hereditory eye condition which causes eventual blindness in several breeds.

Due to the vigilance of responsible owners this condition has largely been eradicated from the Rough Collie gene pool, although breeders continue to be advised to test breeding stock periodically throughout their lives in order that the Rough Collie can remain virtually free from this debilitating condition.



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