Publikationsdatenbank

A critical view on the development of breeding dogs from a pathologist ' s perspective (2019)

Art

Vortrag

Autor

Gruber, A. D. (WE 12)

Kongress

22nd Congress of the European-Veterinary-Society-for-Small-Animal-Reproduction (EVSSAR)

Berlin, 28.06.2019

Quelle

Reproduction in domestic animals = Zuchthygiene

Bandzählung: 54

Heftzählung: Suppl. 2

Seiten: 12 – 13

ISSN: 0936-6768

Sprache

Englisch

Verweise

URL (Volltext): https://onlinelibrary.wiley.com/doi/full/10.1111/rda.13460

DOI: 10.1111/rda.13460

Kontakt

Institut für Tierpathologie

Robert-von-Ostertag-Str. 15
14163 Berlin
+49 30 838 62450
pathologie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

After mutually beneficial relationships for more than 20,000 years, approximately 150 years ago we accelerated in the systematic shaping of several dog breeds towards beauty, extravagance, and similarities to human skull anatomy. Today, we face a breathtaking diversity of dogs which is much greater than the spectrum of breeding products from any wild animal other than the wolf. Given the unparalleled genetic, anatomical, physiological and behavioral distances from its ancestor, we encounter difficulties when trying to define the true nature of “the dog” in terms of animal welfare. However, our benchmarks for canine health versus disease are much easier to define when we consider principles of comparative pathology which apply to all mammals, including humans.

As pathologists, we daily encounter the unwanted side effects of breeding, both on the necropsy floor and in biopsy diagnostics. The complex landscape of lesions, mechanisms, incidences, correlations and risks is only partially documented by a large body of scientific literature, which is, naturally, growing continuously. In an attempt to understand and categorize breeding associated disease, two major groups can be defined which may help to support actions to effectively improve the drama.

First, breeding for anatomic extremes, e.g., extremely short noses in humanized skulls, short legs, giant size, and allegedly beautiful coat and eye color resulted in a wide spectrum of problems that are directly linked to the breeding aim. Large, brachycephalic skulls give rise to a wide spectrum of respiratory, ocular, cutaneous, oesophageal and circulatory complications (1,2), and several with drastically increased rates of caesarean sections (3). Giant breeds face increased risks of developing lethal osteosarcoma and orthopedic conditions (4), and roughly every fourth dachshund will suffer from intervertebral disc disease, with lethal outcome in one out of four (5). Dalmatian dogs and heterozygous carriers of the merle‐factor in several breeds are at risk of deafness (6), which is tightly linked to their marvelous coat color, and color of eyes in Dalmatians in particular. It is assumed that every second heterozygous merle‐factor carrying dog is unable to swim (7), probably due to inner ear defects with orientation deficits. As early as 1967, the World Small Animal Veterinary Association declared concerns for the health and welfare of dogs related to breed standards. Nevertheless, with the present high popularity of such breeds and variants, alleged beauty in the eyes of some breeders and owners is still linked to increasing defects, suffering and early deaths in our “best friends”.

The second group comprises effects largely unrelated to specific breeding aims, which are mainly due to accumulations of incidental genetic defects due to genetic bottlenecks, inbreeding and unnaturally high numbers of offspring from champion individuals, termed “popular sires”. Assisted reproduction may exert significant impact on this scenario. The long list of diseases that fall into this category includes (neuronal) storage diseases, specific tumors (8), atopic dermatitis and gastroenteritis, various forms of epilepsy, and curious lesions such as idiopathic foot pad hyperkeratosis.

In Germany, there is an increasing awareness of the ethical dilemma, with many developments clearly violating the spirit of national animal welfare laws. Since 2014, state veterinarians have repeatedly ordered the castration of dogs and cats the breeding of which would clearly not comply with legal regulations, and with attitudes in the majority of society. Clearly, there is action required. Humanity is a term that describes how responsibly we deal with our subjects and wards.