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Parts 1 and 2 of this article describe the attempt to introduce the bob-tail gene from a Pembroke Welsh Corgi into the Boxer. The introduction of the gene for erect ears was a further option. In the first cross all the progeny loked like rather large Corgis with ears that tended to be erect and several had bob-tails. In the backcross of two bob-tail bitches with bob-tails to a Boxer dog, a range of greatly different progeny were obtained, with long or short legs, long or short coats, bob-tail or normal, but some were very like Boxers. Here the results of a second backcross to a Boxer using a bob-tail bitch of general Boxer appearance. The bitch (Jane) was Boxer white (with a red-fawn patch), the Boxer dog was solid with very limited white markings (lacking the gene for white) and was otherwise brindle in colour.
THE RESULTS
Jane had her litter on schedule and while she she was not in the league of the previous generation which required only two hours to produce a whole litter, she did quite creditably producing her eight pups in eight hours and with relative ease. And, at birth, how did the pups conform with expectations?
* White markings: none were white like the dam or solid like the sire; all showed the expected flashy white markings (Fig.18) unfortunately still regarded by many as essential to the show Boxer. A little surprisingly, as a litter their white markings were quite extensive, yet still fully within Boxer range.
*
Red versus brindle: two were clearly red, five were clearly brindle and one was difficult to tell. Apart from the last one, all was fine.
*
Tails: five had bob-tails (4 bitches and one dog) and the remaining three had normal Boxer tails. Two of the bob-tails were about one-quarter to one third normal length and three had short tails ideal for a docked Boxer. With a 50:50 expectation, luck was with us if one wanted a bob-tali bitch for the next generation.
*
In general appearance they all looked like Boxers.
The head type, which is a characteristic feature of the Boxer even at this early age, was highly evident in all the pups. In fact some of the heads were most promising, with short, broad muzzles and neatly domed skulls.
Over the next week or two it was no longer possible to think of them as 'Borgies'. They were scrutinised as if from a purebred Boxer litter for show quality. The only surprise was that there was a distribution of sizes at birth from the largest pup, weighing 1lb, to the smallest weighing only 9ozs (Fig. 18). There was no association of size with tail type, one of the two biggest puppies having a bob-tail and one of the two smallest having a long tail.
Over the first week, the smaller pups grew disproportionately fast and nearly caught up with their larger sibs. All seemed normal and generally almost too good to be true. But then, as this is a real-life story, things started to go wrong. Mastitis and then kennel cough hit us and the latter got to the puppies. I thought this might be the end of the study. But, perhaps because of their mixed German, Dutch and British Boxer background, plus a dose of Corgi, all but one survived. The smaller members of the litter were knocked back to most .
At the time of writing the seven remaining puppies have reached five weeks of age and we can begin to see what we really have, good and bad. Boxer type prevails (Figs 19 & 20 ). All have long straight legs, short backs and short coats. There is nothing foreign in their build to suggest Corgi in their ancestry. Heads, however, betray them, but only when considered as a litter. Some have Boxer heads of a standard that at this age one would be pleased to have in any Boxer litter. Thus, two have extremely short deep heads that surely derive from the Continental Boxer background, while a third has a finer skull, yet with great muzzle development and with a really beautiful eye (Fig. 21). Only one in fact has a longer head somewhat pointy muzzle that has some suggestion of Corgi. The heads of the remaining three puppies fall between the two extremes but, despite some inadequacy of stop, this would never identify them as other than purebred Boxers. This, at least is the view of the moment. And impressions change every day.
Beyond this, all of the puppies have the undershot jaw, which will not alter, and several have extraordinary, wide, straight mouths which are better than commonly seen in Boxer pups. Maybe this will stay. And eye size looks very good.
There were two surprises. The one pup of ambiguous colour at birth became of interest at two weeks of age when the blackness of its coat appeared more a mis-marking (Fig. 23) than a brindling. It looked as though someone with sooty hands had picked it up, there being a suggestion of banding over the ribs but with the most blackness over the loin and rump. Boxers with more limited degrees of black patches have been seen in this country and abroad and, whenever tested, the condition has not bred on. The patchiness of this puppy looked different, but each day the blackness became less evident, and the puppy may finish up as a sooty red - again not unknown in Boxers.
Of more importance is the development of the bob-tails. Here, I have to express a little disappointment. While two pups have acceptable short tails like their dam, with just a dip at the end attributable to soft tissue and hair, which could be trimmed, the other two each have a definite tail kink (Fig. 23). Despite this additional feature, I think it can still be fairly claimed that one of the original objectives has just about been achieved. We now have several 'bob-tail Boxers' of potential show quality. Time will decide whether the latter is really true.
WHAT ABOUT ERECT EARS?
So far all attention has been given to the bob-tail characteristic and the introduction of the gene into the Boxer. This was one of the original objectives of course and the process was accelerated by the appearance of the remarkably Boxer-like Jane, with her bob-tail, in only the second generation. We did have two other bitches with the stiff Corgi type ears, but both had the short legs and long coats.(Fig.24) Therefore, compared with Jane, breeding from them seemed a big step backwards. However, the option was there and when one came into season, actually before Jane, and the owners were desperate for the bitch to have a litter, we decided to have a try.
The first problem was the choice of stud dog. It seemed to me that that a Boxer with small 'flying' ears might be the most suitable. Ideally, of course, I would have wanted one that was solid to avoid the problem of whites. However, much screening along the benches at shows earlier this year failed to identify a single dog with the required ear type. In desperation, therefore, we simply decided to use one of our own dogs. Again, Gordon Seeney was called into help and with the aid of a platform to equalise the heights, little difficulty was encountered in obtaining a mating. However, the bitch did not get pregnant.
It had been expected that half the puppies would inherit the erect ear gene. Hopefully, these would have been identifiable by, at minimum, a stiffness of the ears.
WHITE MARKINGS THAT BREED TRUE?
The Corgi type of white marking is essentially identical to that of the flashily marked Boxer, white flash on the face, white socks and variably a white collar. The big difference is that whereas breeding such Boxers commonly results in the production of whites, the Corgi white markings breed true. It is possible that the Corgi form of the gene used to exist in Boxers as in the early days of the breed as piebald or check Boxers were known. These days only whites are seen (barring the rare overmarked cases), so the other form of the gene appears to have been lost.
Could it be introduced into the Boxer? In principal, this could easily be done. In the cross of the piebald bitch with a solid Boxer, the near-solid puppies would carry the gene. Crossing such dogs together would generate true breeding flashy animals. I don't know if there would be risk of over-marking with this form of the gene. Corgi people would know. But I suspect that unpigmented third eyelids, which Boxer people hate, might be a problem. Still, the gene could offer one solution were Brussels ever to take over the control of dog breeding and ban all matings that produce white pups! I suspect that the better solution would simply be to "breed up" the limited white markings that already exist in solids,that is, if the demand for flashy white markings, which is driven only by fashion, persists.
THE FUTURE
The original objective of this exercise was to see if one could generate a bob-tail Boxer and in the process evaluate the problems of introducing a gene from one breed into another. But the option of introducing an erect ear carriage also arose when pups with stiff or erect ears appeared in the first generation cross. And then there remained the more scientific component of the study involving canine gene mapping. Where do we go with each of these?
For the gene mapping work we have, as indicated earlier, successfully obtained blood samples from the original Boxer and Corgi parents, from all the crossbred progeny, but only from 12 of the 16 puppies of the backcross generation, lack of interest by the owners being the problem. Hopefully, we will also be able to get blood samples from the new generation, as this material too could add further useful information.
Following up the erect ear option will mean using the bitch shown in Fig. 24. This would mean a big step back to the short legs and more normal head characteristics of the Corgi. After the rapid progress with bob-tails, I feel reluctant to do this. However, when I told the former major German Boxer breed warden, Otto Donner, about the cross and its objectives last year he emphatically declared that in Germany they had already tried to breed erect-eared Boxers following a cross to a Spitz breed and that it could not be done. Well, there's a challenge! Of course, it should be possible. The erect ear carriage is normal to the dog, as it is to most wild animals in which hearing is important. The drop ear is the abnormal. So, I'm sure the erect ear could be established in the Boxer.
The greater problem would be to get an ear shape and size that matches the Boxer head. So, has any Boxer breeder got a suitable dog for the Fig. 24 bitch? I would prefer a solid dog (to avoid the whites) and one of high show quality, but the key requirement would be the small ears carried high, that tend to 'fly'.
Finally, there is the question of the tails. Although the current generation of pups are yet very young, I think one can fairly claim that we now have 'bob-tail Boxers'. But there are still the questions as to the nature of the bob-tail condition itself to be resolved; is it free from other undesirable effects? And, thereafter, there is the effect of the gene in the double dose to be resolved. X-ray examination of the kinky tail pups may provide some answers, and I will proceed with this shortly.
Depending upon the results I could then consider the option of mating bob-tail with bob-tail and screening for foetal loss by ultrasound. However, such an investigation could be achieved much more effectively in those breeds where the bob-tail gene is commonplace.
Whatever the final answers on the bob-tail condition, the fact that it has proved relatively easy to transfer the gene from one breed into another demonstrates that the procedure is perfectly feasible. If it can be done with this dominant gene, it could be done with any other. And with a little more difficulty could be done with a recessive gene too. Maybe it would be fun to demonstrate the feasibility once again - with the erect ear condition. Watch this space!
Legends to Figures in Part 3
Fig.18. The eight puppies from the cross of the white Boxer-like bitch of the second backcross with the solid dog lacking the gene for white. All show the standard flashy white markings of the typical Boxer show dog. A size difference is evident.
Fig.19. A brindle bitch, aged five weeks, 7/8 Boxer, 1/8 Corgi, yet typically Boxer. Her bob-tail is the longest in the litter.
Fig. 20. A red bitch, sister of the brindle in Fig.19, with the shorter bob-tail.
Fig. 21. The larger red dog with promising head and the smaller brindle bitch with blockier Continental head.
Fig. 22. Not available.
Fig. 23. The puppy on the left shows the sooty black markings that are disappearing rapidly. It also has the first kinked tail among the bib-tail dogs in any generation. The puppy on the right shows the more suitabler straight tail, the downwards bend at the end representing only soft tissue and hair.
Fig. 24. One of the stiff eared bitches from the second generation. Boxer markings and coat, and with bob-tail, but obviously short legged.
The first three parts of this article were written in 1996.
Part 1 described the cross of a Boxer bitch with a Pembroke Welsh Corgi made several years earlier. The Corgi had a dominantly inherited bob-tail. A principal objective was to see if, through a series of backcrosses, the Corgi bob-tail gene could be transferred into the Boxer.
Part 2 described the results of the first backcross (second generation) in which two bob-tail crossbred bitches were mated with a Boxer male. The progeny comprised pups of all shapes and sizes but one white bitch that possessed a bob-tail was so Boxer-like that she could, and did, pass for a Boxer.
Part 3 then described the second backcross in which this bitch was mated to a further Boxer male to give the third generation. Several bob-tail pups appeared in this litter too.
Now, in Part 4, the critical steps in these backcrosses are summarised and then the appearance of the third generation progeny, as adults, is illustrated. Finally, the results of fourth generation crosses which could allow registration of the pups as Boxers are presented.
THE CRITICAL STEPS
1. All the first generation progeny proved to be Corgi-like in build. The Corgi features that distinguish the breed from the Boxer could be said to be "dominant". However, 5 of the 7 pups in the litter had bob-tails in accord with expectation for a single dominant gene. Fig.1 illustrates one of the two crossbred bitches from this litter that were used for breeding.
2. Fig. 2 shows the Boxer male to which both bitches were mated. He is my own dog, Steynmere Foreign Service. A total of 16 pups were produced (with remarkable ease) in the two litters and, while several looked very Boxer-like at first, by two to three weeks of age all the Boxer-Corgi differences (long legs vs short legs, longer coat vs shorter coat etc) could be seen to be separating out. No two pups looked alike. However, one white bitch, Jane, looked very much like a Boxer and remained so through to adulthood. She had the long legs, short coat, and general build of a Boxer, and she had a bob-tail (Fig. 3). Only the head was a somewhat untypical. Although clearly Boxer like it looked "unfinished", shallow and without much depth.
The transformation in one generation (Fig 1. mother and Fig.3 daughter) can only be described as amazing. It suggests that very few genes are responsible for the main features distinguishing the Corgi and Boxer, except for the special Boxer head. The white coat colour, of course, was Boxer white and resulted from the doubling up on Boxer.
3. The next step was to breed the white bitch to a Boxer male that was strong in type. Avoiding the white, the solid male Boxella's Chief at Zenmaxkay who is of Dutch/German breeding was used. Eight pups were born. All displayed the typical flashy white markings that characterises the show ring Boxer in this country. None were white or solid as expected from a white x solid mating, and 5 of the 8 had bob-tails. One bob-tail was lost as a result of the bitch getting mastitis and contracting kennel cough.
Significantly, all the pups looked like Boxers both in the nest and by 7 weeks of age when Part 3 of the series was written.
Figs 4a-g now illustrate how they looked at 10 months of age. Coming from pet homes, their show poses are not the greatest but nevertheless I think that they all can pass for Boxers. As four of these dogs have bob-tails (Figs 4a, 4e, 4f and 4g) the transfer of the gene from Corgi into Boxer could be said to have just about been achieved. However, the heads still needed improving. The two bitches shown in Figs 4f & 4g, Paddy and Bobby, were initially retained for breeding but due to changes in my home circumstances ultimately had to be homed and bred elsewhere.
THE FOURTH GENERATION
Breeding dogs over several generations is a slow business, especially through bitches. Therefore, intrigued by the big brindle male, George (Fig 4a), and having one of my Boxer bitches come in season in the Autumn of 1997 when the dog was about old enough to breed, I could not resist the temptation to use him at stud and move through another generation ahead of schedule. The bitch, Steynmere Set The Fashion, suited him well for show points and was especially good in head. Additionally she was strong in breed type .
She whelped eight pups easily but with more to come she stuck and had to have a caesarian. Disaster started here. She had 5 more pups inside her and, although all were delivered alive, two (with normal tails) were tiny and survived only a few days. Worse, the bitch nearly died on the operating table through fluid loss and subsequently had little milk. Three of the 13 (7 with bob-tails) pups were whites and, although they had bob-tails and most promising heads, I opted to put these down to reduce the size of the litter. Even so, with mastitis hitting us again, losses were high and I finished up with only three survivors, two with bob-tails and one with normal tail.
One of the two bob-tails was put in a home where if necessary she could be bred from, but she did not have the best head. The clear pick of litter was a red with a most pleasing head, but she did not have a bob-tail. Although excluded from the breeding study I have kept in touch and, as evident from her photograph taken recently when she was 8 months of age, she looks pure Boxer and, importantly, her head has remained typical (Fig. 5). The transition back to the Boxer had been made, but unfortunately, without the bob-tail. I had to try again, and the two bitches, Paddy and Bobby (Figs 4f & 4g), that I had set aside for the purpose were still available.
Paddy was mated this Spring to Doreen Greaves' CC winning Barbarossa Matador Magic, a red male of predominantly Continental breeding. Bobby was mated just one week later to the Chippendale's RCC winning Santonoaks Red Hot Prospect of Mylicam, an elegant red male who has a lot of my own (Night Rider) breeding behind him. Underlying the use of two different dogs was the thought of crossing bob-tail animals from the two litters together and avoiding excessive inbreeding.
Paddy whelped easily but produced only three pups, two brindles and one white, all bitches. The two brindles had bob-tails but of a type that I had not seen before. They were not as short as those seen previously, being about one-third of normal length, and tapered neatly to a point.
Fig. 6a shows one of these bitches at about 9 weeks old. When I told Peggy Gamble, the pioneer bob-tail Corgi breeder, about these pointed tails she was doubtful about them being bobs. However, they have the filaments of skin at the tips which characterises bob-tails, so I am positive they are bobs; it is just the fleshy pad that is missing. Time will tell if I am right. All three bitches looked like normal Boxers and the heads were better than that of their dam.
Bobby whelped her all red litter by Red Hot Prospect a week later. There were 6 pups. Four of these had typical bob-tails and another had the longer pointed type. The fifth had a normal tail. One of those with a short bob took too long being born and was dead, but the remaining 5 were produced and reared without incident. All appear as standard Boxers although with some variation in the heads.
Figs 6b-6d show three of the short bob-tailed pups. One is a heavily boned, short backed lad (Fig. 6b) who has, at this stage, quite a promising head (not evident in the photo). Remarkably he could be thought of as over-typical, Boxer over-typical.
A sister (Fig 6c) looks quite good but is rather plain in head. A brother is also quite impressive but also lacks in head (Fig 6d).
Over both litters I had a slight excess of bob-tailed pups over the 50% expected.
A difficulty in presenting these photographs is that I know that everyone in Boxers, myself included, tends to focus upon the show faults of these pups, forgetting the main point is that they look like Boxers, not a mixed breed. The probability that their show faults derive from the Boxer parts of their ancestry, not the Corgi part, is also likely to be missed. However, Boxer type now essentially established and so the final task will be develop the show potential. I do not expect this to be any harder than with purebred Boxers. The unique Boxer head seems to be the major problem but then, in my experience, this is also the case within the breed.
In conclusion, although these pups may not fulfill everyone's idea of show quality Boxers, I think it is fair to claim that the original primary objectives of the project have been achieved; a gene has been successfully transferred from one breed to another, and I have my bob-tail Boxers which do not need to be docked.
WHAT ELSE
Clearly another problem, were the exercise ever to have any practical value, would be the Kennel Club's view on the registration of these dogs. Entry to the KC Breed Register seemed possible under Regulation B.2c of the KC Regulations for Classification and Registration (page 3.21 of the 1997/1998 Yearbook). This concerns dogs of impure, or unverified breeding. I put the case for registration to the Kennel Club together with a copy of my original letter to Martin Sinnatt and a copy of his positive reply. I also provided all the details on the successive generations of crosses, including the photographic evidence, and the fact that blood samples for DNA analysis had been collected at each generation. After much time and no doubt much discussion I was advised that the case had been approved. I then had to register each generation from the first cross through to the last and this I did with the help and advice of Brian Leonard. The registrations are now with me. They show the early generations as crossbreds and this last, the fourth generation, as Boxers.
So they can now be formally exhibited at shows and in fact the 8 months old bitch illustrated in Fig 4 did compete at a recent Midland Boxer Club event. She did not get placed, but it was a tough class of 20 odd minor puppies. More importantly, however, no one noted anything atypical about her appearance or temperament. She performed in the ring without special attention other than from those in the know. It will be nice if the bob-tail pups from the recent litters can finish up looking as good.
The final step takes us back to genetics. What will happen when bob-tails are intercrossed? As indicated above, I hope to conduct at least one such intercross but, in reality, the answer must come from the bob-tail Corgi or Valhund breeds in which bob-tailed animals are regularly intercrossed. Until I certain that there are no ill effects associated with the bob-tail gene in double dose, I will keep control of all the registrations. For the present every animal I have sold, bob-tailed or otherwise, has either remained registered in my name, or has had its KC registration endorsed, "Progeny not eligible for Registration".
As to the other possibility of introducing the erect ear gene into the Boxer from the Corgi as originally contemplated, I'm afraid this option is no longer available. I have attempted to mate the one bitch retained for the purpose on several occasions but she has always appeared past time when her owners has notified me. Only if the Boxer Breed Council were to be interested in developing erect-eared Boxers would I contemplate starting such a project again.
Legends to figures
Fig. 1 First generation crossbred, Dolly, one of two with bob-tails used for breeding.
Fig. 2 Boxer, Steynmere Foreign Service, mate for Dolly.
Fig. 3 The selected second generation crossbred, Jane, showing bob-tail, Boxer construction and coat, and Boxer white colour.
Figs. 4 Third generation litter at 10 months of age by the Contintal-bred Boxer, Boxella's Chief at Zenmaxkay ex Jane.
a) Big brindle male, George, with excellent head and mouth, and precision front. A bob-tailed dog of show quality. Used for breeding.
b) Classy red male who regularly goes to Boxer training classes. Docked.
c) Black brindle bitch. Her conformation was excellent and her head typical, although lacking a little filling under the eyes. Docked.
d) Golden brindle bitch. Neatly made but in very light condition. Spayed at an early age. Docked.
e) Red bitch who as a puppy had sooty patching on her coat. At 10 months her pigmentation was absolutely normal. Typical bob-tail but with a single kink.
f) Pretty good brindle bitch, Paddy, with a longer, blunt ended bob-tail with single kink. Nicely constructed though plain of head.
g) Decent red bitch with typical bob-tail. Again plain in head.
Fig. 5 Fourth generation 8 month old bitch by George ex Boxer, Steynmere Set The Fashion. Good enough, but docked.
Fig. 6 Fourth generation bob-tail pups at 9-12 weeks of age.
a) One of two brindle bitches, by Barbarossa Matador Magic ex Paddy, with longer, pointed type bob-tails. Heads promise to be better than Mum's but still a little plain.
b) Solid red male, by Santonoaks Red Hot Prospect for Mylicam ex Bobby. At this stage he exudes Boxer to the point of being over-typical.
c) Red sister showing characteristics of her immediate Boxer ancestry; lacks stop but better head than Mum.
d) Imposing red brother with longer cast head yet still with Boxer expression.
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