Alpakas mit Blauen Augen
Alpakas mit Blauen Augen besitzen ein einzigartiges genetisches Merkmal, das zur Entwicklung von blauen Augen anstelle der typischen dunklen Augen führt, die bei den meisten Alpakas zu sehen sind. Dieses Merkmal ist relativ selten und tritt aufgrund einer Kombination genetischer Faktoren auf.
Für viele Halter wirken blaue Augen zunächst besonders oder attraktiv. In der Alpakazucht ist dieses Merkmal jedoch mehr als nur eine optische Besonderheit. Es kann mit genetischen Faktoren zusammenhängen, die auch Auswirkungen auf die Gesundheit und das Wohlergehen der Tiere haben können.
Aus diesem Grund ist es für Züchter und Halter wichtig zu verstehen, warum manche Alpakas blaue Augen haben, welche genetischen Zusammenhänge bestehen und welche Aspekte bei der Zucht berücksichtigt werden sollten.
Although not all blue-eyed alpacas are deaf, those with white fur and blue eyes have a higher risk of being affected by congenital deafness. Congenital deafness in alpacas can pose challenges in their care and management, as affected animals may have difficulty communicating and responding to auditory cues. Additionally, deaf alpacas may be more vulnerable to accidents and injuries, as they may not hear approaching predators or vehicles.
Alpacas born with congenital deafness face several challenges:
Communication
Deaf alpacas have difficulty communicating with their herd mates and may not respond to auditory cues such as calls or alarms. This can affect their ability to socialize and navigate their environment effectively.
Predation risk
Deaf alpacas are more vulnerable to predation as they may not hear approaching predators. This can put them at a higher risk of attacks from predators such as wolves, lynxes, aggressive dogs, and in the case of young alpacas also badges and foxes.
Safety concerns
Deaf alpacas may be unaware of potential dangers in their surroundings, such as vehicles or other hazards. This can increase the likelihood of accidents and injuries, especially in environments with heavy human activity.
Handling and training
Training and handling deaf alpacas can be challenging, as traditional methods relying on verbal commands may not be effective. Alternative training techniques, such as using visual signals or vibrations, may need to be employed.
Genetische Grundlage blauäugiger weisser Alpakas
To understand the genetic basis of blue-eyed white alpacas, we turn to a comprehensive study conducted by By D. Andrew Merriwether, Ph.D., and Ann M. Merriwether, Ph.D. from Binghamton University at Nyala Farm Alpacas , which sheds light on the intricate genetic mechanisms underlying this unique phenotype. In their study titled "The Genetic Construction of Blue-Eyed White Alpacas," the researchers provide invaluable insights into the inheritance patterns and genetic variations responsible for producing these mesmerizing animals.
At the heart of this genetic construction lies a complex interplay of genes governing coat color and eye pigmentation. Alpacas typically exhibit a range of coat colors, from solid white to various shades of brown, black, and gray. However, the emergence of blue-eyed white alpacas introduces a novel dimension to alpaca genetics, posing intriguing questions about the underlying genetic architecture.
The study reveals that blue-eyed white alpacas are the result of a recessive genetic trait, wherein both parents must carry the gene responsible for producing blue eyes. This gene, referred to as the "blue-eyed white gene," remains elusive and is hypothesized to be associated with specific genetic markers located within the alpaca genome.
What underlies the BEW (Blue-Eyed White) phenotype according to the study?
While the exact mechanism remains speculative, they draw insights from their understanding of similar phenomena in other species. Melanin, comprising both phaeomelanin and eumelanin, which plays a central role in determining skin and fiber coloration in organisms. During development, melanin migrates throughout the body, contributing to various tissues' pigmentation. Notably, melanin also serves as a crucial structural element in cellular components, including the hairs within the cochlea of the inner ear.
In cases where melanin fails to reach these cochlear hairs, their subsequent demise shortly after birth leads to deafness. Similarly, inadequate pigment cell migration to the cells destined to form the eyes can result in the manifestation of blue eyes. The distribution of melanin is orchestrated by the growing neural crest during embryonic development. Melanocytes, specialized cells responsible for melanin production, migrate outward from the expanding neural crest. Within melanocytes, melanin synthesis occurs from tyrosine, an amino acid, catalyzed by the enzyme tyrosinase.
While the understanding of the precise mechanisms governing the BEW phenotype in alpacas is evolving, these insights shed light on the intricate interplay of genetic and developmental factors shaping phenotypic traits across species.
Our recommendation
In the last 20 years, our experience has shown that alpacas with color pigments around the rims of their eyes generally do not carry the gene for blue eyes, and that these alpacas are more associated with inheriting a colored fur (not white) from their ancestors. Therefore, in cases where an alpaca owner is breeding a blue-eyed dam, we recommend using only a stud with pigmentation around the eyes. This reduces the risk of producing a blue-eyed alpaca that could, in rare cases, carry the deaf gene.
