There was no much attention paid until now to bite and teeth quality of Louisiana Catahoula. The reason is that Catahoula is the American breed and there is generally only a little attention focused on this matter. Both NALC standard, valid since 1977 (last revision in 1994) and UKC standard (2008) say that: „A scissors bite is preferred, but a level bite is acceptable. Full dentition is greatly desired, but dogs are not to be penalized for worn or broken teeth. Overshot or undershot bite are serious faults, but not disqualifying“. Catahoula is working breed and working qualities have been always more demanded than an ideal conformation and a superior bite. This is also the heritage we must deal with now.
Evaluation of European breeds and breeding was always more strict in this point of view and more focused on correct bite and full dentition, namely in breeds that preserve more or less normal skull parameters. Thus, scissor bite and full dentition is what most of breed standards demand and faults are more penalized. There is a good reason for it, because an efficient function needs a proper skull and jaw structure and teeth position. However, some anomalies were found also in wild living wolves and some faults are fairly common among various dog breeds even if not wanted.
Adult dogs should have a total of 42 of permanent teeth. Pups have 28 of deciduous teeth.
Full dentition with all adult teeth fully erupted consist of incisors (Incisives – I), canines (Caninus – C), premolars (Praemolares – P), and molares (Molares – M). Upper and lower jaw differ in a number of molars. The teeth pattern is following:
|Maxilla – upper jaw||M2,M1,P4,P3,P2,P1,C,I3,I2,I1-I1,I2,I3,C,P1,P2,P3,P4,M1,M2|
|Mandible – bottom jaw||M3,M2,M1,P4,P3,P2,P1,C,I3,I2,I1-I1,I2,I3,C,P1,P2,P3,P4,M1,M2,M3|
Bite and teeth development lasts quite a long time. Table shows certain steps of this development:
|Age||Deciduous teeth – 28||Adult teeth – 42||Jaws|
|3-6 weeks||Canines erupted|
|4-6 weeks||Incisors erupted|
|6 weeks||Premolares erupted|
|3rd -4th month||Deciduous teeth start falling out = Teething||Level incisors erupted|
|4th-5th month||Central and edge incisors erupted|
|4th-6th month||Canines erupted|
|4th-5th month||Premolares and molares erupt|
|7th month||Molars erupted, full dentition should be fully erupted|
|9th-11th month||Upper and bottom jaws grow independently until this time|
|1th-2nd year||Lower level incisors settling down|
|2nd-3th year||Settling lower central incisors|
|3th-4th year||Settling upper level incisors|
|5th year||Settling upper central incisors|
In order to understand severity of dental faults it is good to know what is correct and why. A way how a wolf uses its teeth would be the best example to explain this matter. Concerning Catahoula, it a good example, too, because this breed has got most probably a red wolf among its ancestors. It could also support one of explanations of Schutzhund as a not very suitable activity for this breed that was mentioned by Anke Boysen elsewhere (http://www.ealc.info/en/working-dog-catahoula/).
In training and performing Schutzhund the preferred grip is a „full mouth bite“. The dog should grasp subject’s arm or leg well into its mouth, between its molars and premolars and behind the canines. This is not the way a wolf does it. A wolf grips with the front of his mouth. The four canine teeth puncture the prey and their overlapping structure combined with jaw strength prevents the prey from pulling free. Once the prey is down, the premolars are used for biting off chunk of meat. The upper P4 and the lower M1 on each side are especially developed for this task. The carnasals are the most massive teeth in the canine jaw. They are very sharp and their location mid-way down the length of the jaw puts them at the point where jaw pressure is greatest. The incisors located at the front of the mouth are specialized for delicate work. They nibble the last bits of meat off bones and are also handy for scratching an itch or pulling something bothersome out of the coat or from between the pads. Molars, other than mentioned, are flat for grinding plant matter. Wolves eat also some fruits, grasses and other plant matter and this type of food must be chewed a little to start digestive process.
All those specialized teeth have their proper position in the jaw, which is determined by their function, and they require a properly formed skull and lower jaw to function efficiently. The muzzle must be long enough and broad enough to accommodate the teeth in their proper locations. Jaw strength comes not only from the muscles, but the shape of the skull (1).
Most working breeds with normal skull mantained generally above mentioned dental structure, because it is the most efficient also for their work such as herding, hunting, etc. Nevertheless, missing teeth and malocclusions are typical dental faults in these breeds.
Research among wild wolves showed that the most frequent anomaly was the absence of the last molar in the lower jaw, M3. As it does not change the function, the absence of M3 should not be considered breeding deficiency also in dogs (2).
Missing teeth (hypodontia) is the fault observed often also in Catahoula breed. This fact and the degree of the fault should be evaluated according to which teeth and how many are missing. Some of premolars (P1, P2 or P3) and some of molars (M2, and most probably also M3) are most frequently among missing teeth. If the first premolar (P1), one of the smallest teeth, is missing, it is much less a problem than missing the upper P4 or M1 which belong to the most important teeth (see above). The more teeth that are missing, the more faulty and less functional the bite becomes.
As missing teeth like to appear in certain families and lines, it is important to take this into account when choosing breeding partners and to avoid those affected the same way. Inheritance of hypodontia is not possible to describe by a simple model and its analysis indicated heterogenous genetic control of different forms. Whereas the absence of P2 can be described by the recessive major-gene model, the absence of P4 have more complex genetic mechanism (3).
Faults of bite concern also Catahoula breed. Dog’s bite is the way his teeth fit when his upper and lower jaws are closed. The standard type is a scissor bite, in which the upper incisors just overlap and touch the lower incisors and all premolars and molars fully fit. Another possible variation is a tight scissor bite, when upper and lower incisors touch each other more then above or lower incisors are outwards of longitudinal line of bottom jaw. Catahoula has also a level (even) bite permitted by the breed standard. It is when the upper and lower incisors meet exactly, surface to surface. This means that teeth can be worn down much faster, but it does not affect actually the function and both jaws are of the same length as in previous cases. Level bite is considered normal in some breeds, including Catahoula, nevertheless, some consider this type of bite as an expression of underbite. On the other hand, research among wild wolves showed that fully a third of animals had even bites. No structural fault is tolerated to this degree in a natural species, particularly in a feature so critical to the survival of that species.
More serious bite faults are those caused by uneveness of both jaws.
Undershot bite is when the upper jaw is perceptibly shorter than the lower jaw and the lower incisors are located in front of the upper ones. This is typical for some breeds such as Boxer, Bulldog, Pug, Pekinese, etc. that have a shorter foreface and longer lower jaw.
However, it is considered a serious fault in breeds with normal skull parameters. This fault is inherited trait.
Overshot bite is caused by physically longer upper jaw than the lower one and the uneveness between them is larger than 2 mm. This fault occurs more often among dog breeds nowadays. Contrary to undershot, this fault can be controlled by genetics, nutrition, environment and by mechanical forces generated by the interlock of the upper and lower teeth. Overshot can affect the mouth’s function more than undershot and indicates usually weakness in the lower jaw.
The incidence of level bites is increasing among Catahoulas beside some missing teeth. Undershot bite is one of more serious faults that occur in this breed. There is no doubt that such faults and abnormalities are inherited. Upper and lower jaws grow independently, factors influencing a size of jaw are different from those affecting the size of teeth and various genes are involved in this process. These problems are polygenic resulting from the action of many genes, thus it is difficult to eliminate them because there is no single „bad bite“ gene. The length of the skull and the muzzle play a role and a dominant way of a shorter skull inheritance is known. Thus, this must be taken into account in case of Catahoula, too. A combination of parents with rather different length of their muzzles is not recommended, because it could increase the incidence of faults in bites and occurrence of undershot or overshot bites among offsprings. And we have proved already that Catahoulas may vary in their muzzle size in more than one third of its length.
Inheritance and elimination of severe dental faults is difficult in breeds more numerous than Catahoula. There is impossible to exclude from breeding all individuals that show any fault due to complicated, polygenic and often recessive way of inheritance in such a rare breed. However, those showing more serious faults, such as the overshot and the undershot bite and numerous and the most important teeth missing, should be surely excluded from breeding.
Nevertheless, it is not quite clear now how these faults are spread over Catahoula population in Europe. There is no statistic here or in the country of origin and the recessive way of inheritance of some anomalies means that many dogs can carry genes for such traits. The increasing incidence of level bite occurrence among young Catahoulas is warning, because it is not clear how this can affect future breeding. Although it is not possible to eradicate all faults fully, breeders can lower their incidence by selective breeding. However, it is necessary to map the problem within the breed first. Therefore thorough and wide spread check in offsprings is necessary to find some relations among particular parents and faults occurrence. It should be done both by breeding clubs and breeders themselves at least at the age of 1 or 2 years, when all faults are visible already. Our experience shows that tight scissor bite observed at one year of age changed quite often to the level bite at two or later. The analysis and statistics should be done and published by breeding clubs, because it is beyond any breeder’s possibility, and all responsible breeders should obtain such informations for their proper decisions in breeding.
Written by RNDr. Helena Synkova
Most important references:
(1) C.A. Sharp: So Bite Me: A Close Look at Canine Dentition, First printed in the Aussie Times, July-August 2002.
(3) Axenovich, TI; Zorkoltseva, IV; Aulchenko, YS; et al :Inheritance of hypodontia in Kerry Blue Terrier dogs. Russian Journal of Genetics 40/5: 529-536 , 2004.