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Alaskan sled dogs are a mixed breed dog selected strictly for their racing performance. A) Top row: Sprint racing teams of "traditional" Alaskan sled dogs (no purebred crossings in the last 5 generations) and Pointer crossed Alaskan sled dogs. Spandex dog coats (in blue) are commonly used on shorter-haired Pointer × Alaskan sled dogs when temperatures are ≤10'F. B) Middle row: Sprint sled dogs of 25% or greater Pointer ancestry according to their written pedigree records. C) Bottom row: "Traditional" Alaskan sled dogs from distance racing teams. All photos were taken between 2006-2009 of dogs competitively racing in high performance kennels.
Source publication
The Alaskan sled dog offers a rare opportunity to investigate the development of a dog breed based solely on performance, rather than appearance, thus setting the breed apart from most others. Several established breeds, many of which are recognized by the American Kennel Club (AKC), have been introduced into the sled dog population to enhance raci...
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Alaskan sled dogs are a genetically distinct population shaped by generations of selective interbreeding with purebred dogs to create a group of high-performance athletes. As a result of selective breeding strategies, sled dogs present a unique opportunity to employ admixture-mapping techniques to investigate how breed composition and trait selecti...
Citations
... This sport has two main variants, and the selection of dogs varies between them, although it has always been carried out on a sled dog basis. Thus, for the middle distance (races up to 40 km) the most common canine breed used is Alaskan sled dog (Huson et al., 2010), whereas for the sprint variant (races up to 6 km) the Greyster sled dog is used. However, no study has been carried out on these canine breeds regarding their MSTN levels compared to other breeds, or muscle development or other factors that could influence these levels. ...
... Genetic selection of sled dogs has been carried out by crossing different canine breeds to obtain certain characteristics related to the specific breed type. Genomic principal components studies with sled canine breeds demonstrated genetic substructure related to selection for sprint or middle distance competition (Huson et al., 2010;Thorsrud and Huson, 2021). Our results showed that higher body weight (correlated to muscular mass) and muscular mass in sled dogs than in non-sled dogs, and within the sled dog breeds evaluated, greater muscular development in the Greyster breed, selected for sprint. ...
... Working populations of sled dogs survive. Alaskan sled dogs are bred solely for physical performance, including outcrossing with various breeds (9). Greenland sled dogs are an indigenous land-race breed that have been used for hunting and sledging by Inuit in Greenland for 850 years, where they have been isolated from contact with other dogs (10). ...
We reconstruct the phenotype of Balto, the heroic sled dog renowned for transporting diphtheria antitoxin to Nome, Alaska, in 1925, using evolutionary constraint estimates from the Zoonomia alignment of 240 mammals and 682 genomes from dogs and wolves of the 21st century. Balto shares just part of his diverse ancestry with the eponymous Siberian husky breed. Balto's genotype predicts a combination of coat features atypical for modern sled dog breeds, and a slightly smaller stature. He had enhanced starch digestion compared with Greenland sled dogs and a compendium of derived homozygous coding variants at constrained positions in genes connected to bone and skin development. We propose that Balto's population of origin, which was less inbred and genetically healthier than that of modern breeds, was adapted to the extreme environment of 1920s Alaska.
... Considerable progress has been made in the elucidation of the canine genome, 30,84 this highlights canine breeds which evolved from the ancestral wolf genome and the susceptibility of different canine breeds to specific diseases [85][86][87][88][89][90][91][92] (see Appendix S1). ...
Animal models have been invaluable in the identification of molecular events occurring in and contributing to intervertebral disc (IVD) degeneration and important therapeutic targets have been identified. Some outstanding animal models (murine, ovine, chondrodystrophoid canine) have been identified with their own strengths and weaknesses. The llama/alpaca, horse and kangaroo have emerged as new large species for IVD studies, and only time will tell if they will surpass the utility of existing models. The complexity of IVD degeneration poses difficulties in the selection of the most appropriate molecular target of many potential candidates, to focus on in the formulation of strategies to effect disc repair and regeneration. It may well be that many therapeutic objectives should be targeted simultaneously to effect a favorable outcome in human IVD degeneration. Use of animal models in isolation will not allow resolution of this complex issue and a paradigm shift and adoption of new methodologies is required to provide the next step forward in the determination of an effective repairative strategy for the IVD. AI has improved the accuracy and assessment of spinal imaging supporting clinical diagnostics and research efforts to better understand IVD degeneration and its treatment. Implementation of AI in the evaluation of histology data has improved the usefulness of a popular murine IVD model and could also be used in an ovine histopathological grading scheme that has been used to quantify degenerative IVD changes and stem cell mediated regeneration. These models are also attractive candidates for the evaluation of novel anti‐oxidant compounds that counter inflammatory conditions in degenerate IVDs and promote IVD regeneration. Some of these compounds also have pain‐relieving properties. AI has facilitated development of facial recognition pain assessment in animal IVD models offering the possibility of correlating the potential pain alleviating properties of some of these compounds with IVD regeneration. Animal models of IVD deneration have yielded invaluable information on the pathobiology of this degenerative condition and identified prospective therapeutic targets.The complexity of the degenerative changes and multiple therapeutic targets identified by these models suggests artificial intelligence methodology may be required to unravel these complexities and provide a rationale way forward in the development of effective repair strategies.
... Alaskan sled dogs (ASD), also known as Alaskan Huskies, were originally bred as working dogs for hauling cargo-laden sleds over snow-covered arctic terrain [1]. Over the years, they have evolved as highly aerobic mammals and elite endurance athletes through selective breeding with pure-bred dogs and are used in modern sled dog racing [2,3]. ...
Congenital laryngeal paralysis (CLP) is an inherited disorder that affects the ability of the dog to exercise and precludes it from functioning as a working sled dog. Though CLP is known to occur in Alaskan sled dogs (ASDs) since 1986, the genetic mutation underlying the disease has not been reported. Using a genome-wide association study (GWAS), we identified a 708 kb region on CFA 18 harboring 226 SNPs to be significantly associated with CLP. The significant SNPs explained 47.06% of the heritability of CLP. We narrowed the region to 431 kb through autozygosity mapping and found 18 of the 20 cases to be homozygous for the risk haplotype. Whole genome sequencing of two cases and a control ASD, and comparison with the genome of 657 dogs from various breeds, confirmed the homozygous status of the risk haplotype to be unique to the CLP cases. Most of the dogs that were homozygous for the risk allele had blue eyes. Gene annotation and a gene-based association study showed that the risk haplotype encompasses genes implicated in developmental and neurodegenerative disorders. Pathway analysis showed enrichment of glycoproteins and glycosaminoglycans biosynthesis, which play a key role in repairing damaged nerves. In conclusion, our results suggest an important role for the identified candidate region in CLP.
... The Alaskan husky is a type of dog specifically bred for dog sledding. While the Alaskan husky is not a registered dog breed, this dog type represents a genetically distinct population of dogs despite its unregulated breeding program, based on a mix of registered dog breeds, which predominantly includes Siberian Husky and Alaskan Malamute and to a lesser extent Saluki and range of pointer breeds (Huson et al., 2010;Thorsrud & Huson, 2021). ...
Domesticated animals are generally assumed to display increased sociability toward humans compared to their wild ancestors. Dogs (Canis familiaris) have a remarkable ability to form social relationships with humans, including lasting attachment, a bond based on emotional dependency. Since it has been specifically suggested that the ability to form attachment with humans evolved post-domestication in dogs, attempts to quantify attachment behavior in wolves (Canis lupus) have subsequently been performed. However, while these rare wolf studies do highlight the potential for wolves to express human-directed attachment, the varied methods used and the contrasting results emphasize the need for further, standardized testing of wolves. Here, we used the standardized Strange Situation Test to investigate attachment behavior expressed in wolves and dogs hand-raised and socialized under standardized and identical conditions up until the age of testing. We found that 23-week-old wolves and dogs equally discriminated between a stranger and a familiar person, and expressed similar attachment behaviors toward a familiar person. Additionally, wolves, but not dogs, expressed significantly elevated stress-related behavior during the test, but this stress response was buffered by the presence of a familiar person. Together, our results suggest that wolves can show attachment behaviors toward humans comparable to those of dogs. Importantly, our findings demonstrate that the ability to form attachment with humans exists in relatives of the wild ancestor of dogs, thereby refuting claims that this phenotype evolved after dog domestication was initiated.
... While the aforementioned breeds are all common sled dog breeds, our daytime model found that Alaskan huskies were significantly more active than non-Alaskan husky breeds. Alaskan huskies are the result of selectively breeding among several working dog breeds to achieve the desired traits (e.g., speed, endurance, work ethic) for sled dog racing 41 . Staff at Canmore confirmed that Alaskan huskies were the hardest working breed and ideal for running sled tours due to their strong desire to pull for long durations (J. ...
There are limited studies investigating the combined effects of biological, environmental, and human factors on the activity of the domestic dog. Sled dogs offer a unique opportunity to examine these factors due to their close relationship with handlers and exposure to the outdoors. Here, we used accelerometers to measure the activity of 52 sled dogs over 30 days from two locations in Canada. The two locations differ in the working demands of dogs, therefore we used linear mixed effects models to assess how different factors impact daytime and nighttime activity of working versus nonworking dogs. During the daytime, we found that males were more active than females among nonworking dogs and younger dogs were more active than older dogs among working dogs. Alaskan huskies had higher activity levels than non-Alaskan husky breeds in working sled dogs during the day. Nonworking dogs were slightly more active during colder weather, but temperature had no effect on working dogs’ activity. The strongest predictor of daytime activity in working dogs was work schedule. These results indicate that the influence of biological factors on activity varied depending on dogs’ physical demands and human activity was the most powerful driver of activity in working dogs.
... Siberian Huskies are known for their aloof behavior and are considered independent, often making them a more challenging breed to train [4]. They are also known for their physical prowess and ability to work in extreme conditions and are considered strong runners over long distances [5]. Due to their status as an American Kennel Club (AKC) recognized breed, Siberian Huskies are subject to strict selection on their appearance and any performance characteristics for kennels that continue to race them, which has led to a closed breeding population [6]. ...
... Alaskan sled dogs are an admixed breed selected primarily on performance [5]. Initially bred for transportation, the breed transitioned to racing with the advent of mechanical transport in the arctic [2]. ...
... In addition to the genetic pattern unique to Alaskan sled dogs, both performance subpopulations show genetic ancestry, including Siberian Husky and Alaskan Malamute. While these two arctic breeds are the predominant purebred genetic signatures found in the distance sled dogs, the dogs bred for sprint racing tend to have ancestry that includes Pointers and Salukis as well [5]. Within Alaskan sled dogs, the performance subpopulations show genetic divergence likely reflecting variation in ancestry and admixture as well as prioritization of speed versus endurance [5,10]. ...
Background
This study describes the presence and frequency of health traits among three populations of dogs traditionally used for sledding and explores their ancestry and breed composition as provided by the commercially available Embark dog DNA test. The three populations include the purebred Siberian Husky and the admixed populations of Alaskan sled dogs and Polar Huskies. While the Siberian Husky represents a well-established breed with extensive historical and health data, the Alaskan sled dog is less studied but has been the subject of nutritional, physiological, and genetic studies related to ancestry and performance. In contrast, the Polar Husky is a relatively obscure and rare group of dogs used for arctic exploration with very little-known information. The three populations were compared using Embark results, providing new insight into the health traits circulating within the populations and the potential ancestral linkage of the health traits between the sledding populations. Embark results are based upon 228,588 single-nucleotide polymorphisms (SNPs) spanning the canine genome, characterized using a custom-designed Illumina beadchip array.
Results
Specifically, breed composition was summarized for the two admixed populations with most of the dogs being predominantly categorized as Alaskan husky- type dog or “Supermutt”. Mitochondrial and Y chromosome haplogroups and haplotypes were found with Alaskan sled dogs carrying most of the haplogroups and types found in Siberian and Polar Huskies. Genomic principal component analysis reflected population structure corresponding to breed and substructure within the Alaskan sled dogs related to sprint or distance competition. Genetic markers associated with Alanine Aminotransferase activity, Alaskan Husky Encephalopathy, dilated cardiomyopathy, Collie eye anomaly, degenerative myelopathy, ichthyosis, and factor VII deficiency were identified in the populations of sledding breeds.
Conclusion
These results provide a preliminary description of genetic characteristics found in sledding breeds, improving the understanding and care of working sled dogs.
... The Alaskan husky is an unofficial breed, resulting of selective breeding strategies related to performance (Brown et al., 2015;Huson et al., 2010). The dog's type may change depending on the geographic location, the lineage and the racing style (sprint vs endurance) (Huson et al., 2010(Huson et al., , 2012. ...
... The Alaskan husky is an unofficial breed, resulting of selective breeding strategies related to performance (Brown et al., 2015;Huson et al., 2010). The dog's type may change depending on the geographic location, the lineage and the racing style (sprint vs endurance) (Huson et al., 2010(Huson et al., , 2012. In our study, we studied Alaskan Huskies both bred and trained in distance running. ...
This study aimed to investigate the effect of two different gang-lines on the pulling angle of sled dogs. It was hypothesised that dogs would run with a straighter angle of pull (in relation to the main-line) in stick gang-lines (STICK) than they would do in traditional gang-lines (TRAD). Eight sled dogs, divided into two teams, ran a 3.1 km trail twice in both types of gang-lines, pulling a quadbike on dry ground. Each dog remained in its team in the same position (side of gang line, and forward or back in the line) for both runs, using both types of lines in randomised order between the runs. Markers were placed on the dogs and on the main lines, and the runs were recorded by a video camera. The dogs’ angle of pull measured from the video recordings was compared between the two conditions. Thirteen positional measurements for each dog during each run were taken. The dogs were used to running in TRAD and were not acclimatised to STICK. Data was analysed using Wilcoxon and Spearmans rho tests. Data regarding individual dogs (n=13), teams (n=52), dogs’ placements in teams (n=4), and gang-line related pulling angles (n=104) was analysed. Overall, the position of the dogs was straighter when pulling in STICK, than when pulling in TRAD, with a median of 19° (inter quartile range (IQR) 24.75°) and 32° (IQR 25.75°), respectively (P<0.001). Between the two teams, there was no significant difference in pulling positions when running in STICK (P=0.543), but there was in TRAD (P<0.001). In individual assessment, six of the eight dogs ran in a straighter position (P=0.003 to 0.046) in STICK. Dogs running in the front of both teams pulled significantly straighter when in STICK (21°; IQR 23.75) than in TRAD (median 39°; IQR 18; P<0.001).
... Alterations in Ca 2+ entry and intracellular Ca 2+ regulation have been considered secondary to disease-causing mutations in several models of polyQ SCAs -SCA1, SCA2, SCA3 and SCA6 [178,220,222,[257][258][259]. In particular, disruption of Ca 2+ signaling in Purkinje cells is thought to be a key mechanism in the pathogenesis of these diseases -as these neurons express a range of Ca 2 + channels, Ca 2+ -dependent kinases and phosphatases, and Ca 2+ binding proteins [179,257,260,261] -making them attractive therapeutic targets. As an example, the overexpression of inositol 1,4,5-phosphatase suppressed intracellular calcium release and improved motor performance in SCA2 mice [221]. ...
Introduction:
Six of the most frequent dominantly inherited spinocerebellar ataxias (SCAs) worldwide - SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17 - are caused by an expansion of a polyglutamine (polyQ) tract in the corresponding proteins. While the identification of the causative mutation has advanced knowledge on the pathogenesis of polyQ SCAs, effective therapeutics able to mitigate the severe clinical manifestation of these highly incapacitating disorders are not yet available.
Areas covered:
This review provides a comprehensive and critical perspective on well-established and emerging therapeutic targets for polyQ SCAs; it aims to inspire prospective drug discovery efforts.
Expert opinion:
The landscape of polyQ SCAs therapeutic targets and strategies includes (1) the mutant genes and proteins themselves, (2) enhancement of endogenous protein quality control responses, (3) abnormal protein-protein interactions of the mutant proteins, (4) disturbed neuronal function, (5) mitochondrial function, energy availability and oxidative stress, and (6) glial dysfunction, growth factor or hormone imbalances. Challenges include gaining a clearer definition of therapeutic targets for the drugs in clinical development, the discovery of novel drug-like molecules for challenging key targets, and the attainment of a stronger translation of preclinical findings to the clinic.
... 26 Alaskan Huskies, although not an "original" breed, result from a mixture of some of these "original" breeds. Alaskan Malamute, Siberian Husky, Pointer, Saluki and Anatolian Shepherd were the main breeds that initially made up the Alaskan Husky genetically (Huson et al. 2010:1). Hugo once told me: "así como los perros de trineo sienten la necesidad de correr y tirar, el border collie es un perro que siente la necesidad de agrupar, y es por eso que es un perro pastor tan bueno". ...
This study examines dogs that pull sledges in tourist activities in Ushuaia (capital of Tierra del Fuego province) and their relations with their breeders (the mushers) and with the tourists they both work for. Nevertheless, during my field research I also came across other dogs in other contexts, among them the numerous companion dogs abandoned in the city and the so-called “wild dogs”, who live in rural areas and are thus seen by Fuegians as “harmful animals” and an “invasive alien species” - that is, a problem to be solved. In this paper I consider sled dogs and wild dogs, and the different statuses that dogs can assume in these different contexts in which animals and humans relate, considering that in Tierra del Fuego canine work operates as a domesticity regime.
