Interesting Case Of Severe Inbreeding

[asal]

Numbering less than forty at the present time, the Spanish Mustangs from the Cerbat Mountain area of northwestern Arizona are some of the purest Spanish descendants in the United States. Documentation obtained from a pioneer rancher family in l966 and published in a national magazine that same year stated the herd was present when the family settled in the area in the l860's and to their knowledge, no outside blood had ever been introduced. The local Indians made no claim upon the horses stating they had "always been there". The more plausible explanation for the Cerbat herd is the prevailing theory of escape or loss from early Spaniards. A study of the history of Arizona and northern Mexico reveals a number of Spanish expeditions ranging into Arizona, New Mexico and California. Loss, escape, theft by Apaches and other means would easily supply the seed stock into the Cerbat area. Indeed, blood testing of these horses shows without a doubt that they carry Spanish "markers".

Living in an extremely inhospitable environment at an altitude ranging from 5000 to 7000 feet, this original herd evolved into an exceptionally tough, agile horse with extreme endurance and survival ability.

Due to drought conditions in the area in l971, ranchers began eliminating these historic animals to provide more water for the range cattle, not realizing wild horses will dig for water and thereby open up water holes for the cattle as well. A local rancher who apparently regretted the destruction of these last survivors, gave permission to a friend, a veteran Arizona cowboy, to capture the herd and plans for capture progressed slowly. Due to the extreme difficulty in getting vehicles into the area at that time, weeks were spent hauling materials to fence off any remaining waterholes and to build an enclosure around the main source of water. Once the "trap" was constructed, more days were spent in a camouflaged hole waiting for individual horses to come in to water. Once inside, a hand operated trip wire dropped the gate and the horses were trapped. A second corral located off the trap held the horses as they were caught and feed and water was provided. A total of less than 20 animals were eventually captured and brought down to the flatlands where they were branded and issued the required Arizona paperwork.

The group was divided among several people with a number of animals going to the state of Washington. Little or no further information is available concerning this group other than it is assumed that they were either dispersed or died. One stallion and three mares were released in an adjacent mountain range some miles distant from the original capture site by the capturing cowboy. The remaining horses were taken to the Phoenix area and later were moved to Colorado with one stallion being placed on the Cayuse Ranch in Oshoto, Wyoming, the home of Robert E. Brislawn, founder of the Spanish Mustang Registry.

A year later the small herd that had been turned loose were water trapped and the foals were removed and brought to Phoenix, consisting of a yearling stallion, two yearling fillies and one weanling filly. Three were purchased by Apache Trail Ranch, then residing north of Phoenix. Realizing the rarity of these horses it was decided to preserve the genetics by producing a pure breeding herd of Cerbat animals, however with only one stallion and two mares, the future was not bright, but with the acquisition of two mares from the Colorado group, the genetic variation was improved. Though the original horses were small in size, with only one individual reaching more than l3 2 hands, the succeeding generation leaped in size by more than a hand, substantiating a theory that the small size was caused by a less than hospitable environment in the mountains. Extremely healthy and strong, those animals surviving for the first year of their lives in the mountains remained small. The one weanling filly, due to better feed, grew to almost l5 hands. Subsequent generations have proved the genetic size to be from l4 2 to l5 hands.

Due to the extreme roughness of the terrain from which this group came, the fact that they are documented prior to the settling of the area by white settlers over l30 years ago and the fact that the Indians made no claim upon them, coupled with the extremely heavy Spanish influx into the Arizona area for hundreds of years, it is highly probable the Cerbat herd is one of the purest groups of feral Spanish descended horses in existence. Additional evidence gathered by genetic blood testing by the University of Kentucky proves them to be of Spanish descent. Though the blood testing shows them to be heavily inbred and from a "closed" herd situation, like many wild animals in similar situations, apparently all defective genetic material has been bred out, i.e., any animals possessing abnormal or imperfect genes were culled naturally, leaving only those with superior qualities designed for survival to reproduce. Only the size was decreased due to reduced food supply.

Further evidence of the "Spanish connection" is the fact that a number of these Cerbat horses are laterally gaited, doing a very credible "paso" gait though without the extreme action of its cousins, the Paso breeds, which is not at all surprising as they carry genes similar to the Peruvian Paso breed indicating a common ancestor.

In l990 surprising news arrived - a very small group of horses believed to be descended from the handful left in l971 were found in the same area. A group of eight was water trapped and blood samples taken and sent to the University of Kentucky for comparison with those taken from the horses captured in l971. Though even more inbred they did indeed match up with the earlier group. It is probable that this new group had no more than five ancestors and no less than three according to the blood tests. If so, this would make them extremely inbred but again, disproving all the detrimental effects commonly associated with inbreeding, the new Cerbats were healthy, strong and actually a bit larger than the original group. Lateral gaits are evident in the newer horses and though undeniably related to the older group, the addition of the new ones to the breeding program was a welcome asset.

Disposition of the Cerbats is outstanding, quick to learn, intelligent and willing, with a penchant for association with humans. Due perhaps to their centuries of mountain living, or simply perhaps to their genetic inheritance, their legs and feet are excellent with well boned legs and thick walled feet. Backs are short, hindquarters are sturdy, deep and powerful. Chestnuts on forelegs are small and smooth, extremely small or non-existent on the rear legs. Ergots are tiny or non-existent. The ears are small and curved, eyes are rather high set. A definite relationship to the old type Andalusian can be seen in the facial profile. The chest is rather narrow compared to American breeds and well "veed" up. Shoulders are laid back and heart girth is deep. A product of their Spanish inheritance plus their more recent feral environment, they are a tough, hardy, extremely durable animal. One interesting fact is that resting pulse rate in all individuals tested is rather low - in the low 30's which should be of value in any type of endurance competition.

There is not much to choose from in color as bay and chestnut seems to be a consistent part of their genetic inheritance, however at least 50% of these bays and chestnuts are also roans. A rather odd occurrence in the Cerbats is that roan foals are born roan, whereas in many other breeds roan foals show their roan coats only after the shedding of the foal coat. They are extremely consistent in reproduction, not surprising considering they are so closely akin in genetic makeup. The mares have no difficulty in foaling the origiinal Cerbat mares produced well into their 20's. Foals are strong at birth and usually on their feet and nursing within l5 to 20 minutes, a necessity when living in predator country for generations.

Though still small in numbers in the pure state, the herd has been preserved and with future expected growth, a small number has been made available to a select few that wish to continue to breed them. Half and five-eighth Cerbat horses have done well in competitive and endurance rides as well as in three day eventing. The future looks bright for a herd doomed to extinction thirty years ago.

Yet what is the cause of ALL evil in animals bred by humans odd eh?

this is the website i found it on and there is pages of photos of them

http://www.angelfire.com/az/xochitl/Cerbats.html

Edited September 9, 2011 by asal

[Missymoo]

interesting read! Thanks for sharing!

[Rysup]

Very interesting read!

[Andisa]

"Though the blood testing shows them to be heavily inbred and from a "closed" herd situation, like many wild animals in similar situations, apparently all defective genetic material has been bred out, i.e., any animals possessing abnormal or imperfect genes were culled naturally, leaving only those with superior qualities designed for survival to reproduce."

I think this is the most important part though - mother nature being the hard bitch that she can be has made sure that only the strong survived - we as humans have taken over and nurtured young that would have other wise died.

[oakway]

Mother Nature.......the greatest leveler of all.

[Bisart Dobes]

Yes, mother nature knows best. Selecting For Vigor - ALWAYS high in importance in the final decision on those puppies to breed on with.

[Alyosha]

"Though the blood testing shows them to be heavily inbred and from a "closed" herd situation, like many wild animals in similar situations, apparently all defective genetic material has been bred out, i.e., any animals possessing abnormal or imperfect genes were culled naturally, leaving only those with superior qualities designed for survival to reproduce."

Similar to the theory behind the origins of the arabian horse, which has been deliberately closely inbred for thousands of years, and is the most prepotent horse breed that it has been used to improve the health and quality of nearly every other horse and pony breed in the world. In fact the entire thoroughbred breed is descended from only four arabian stallions.

Vigour is vital yes, but inbreeding in essence is not necessarily detrimental. Inbreeding weakness and faults is.

Thanks for posting asal, a very interesting read.

[Steve]

"Though the blood testing shows them to be heavily inbred and from a "closed" herd situation, like many wild animals in similar situations, apparently all defective genetic material has been bred out, i.e., any animals possessing abnormal or imperfect genes were culled naturally, leaving only those with superior qualities designed for survival to reproduce."

I think this is the most important part though - mother nature being the hard bitch that she can be has made sure that only the strong survived - we as humans have taken over and nurtured young that would have other wise died.

Yep its not in breeding that has created problems - its selection.

Edited September 10, 2011 by Steve