The age of cattle is determined chiefly by examination of the teeth, and less perfectly by the horn rings or the length of the tail brush; due to bang-tailing, which is the act of cutting the long hairs at the tip of the tail short to identify the animal after management practices, the last method is the least reliable.
Cattle are placed in a cattle crush in order to restrain them prior inspecting the mouth and amount of teeth that each animal has.
The temporary teeth are in part erupted at birth, and all the incisors are erupted in twenty days; the first, second and third pairs of temporary molars are erupted in thirty days; the teeth have grown large enough to touch each other by the sixth month. Temporary incisors or "milk" teeth are smaller than the permanent incisors.
Cattle have thirty-two teeth, including six incisors or biting teeth and two canines in the front on the bottom jaw. The canine teeth are not pointed but look like incisors. The incisor teeth meet with the thick hard dental pad of the upper jaw. Cattle have six premolars and six molars on both top and bottom jaws for a total of twenty-four molars. The teeth of cattle are suited primarily for grinding, and they use their rough tongues to grasp grass and then nip it off between their incisors and the dental pad. [1]
There is controversy on the reliability of attempting to tell the age of cattle by their teeth, as rate of wear can be affected by the forage that is grazed. Drought or grazing on sandy country will also affect rate of wear.
The following is a guide:
The development is quite complete at from five to six years. At that time the border of the incisors has been worn away a little below the level of the grinders. At six years, the first grinders are beginning to wear, and are on a level with the incisors. At eight years, the wear of the first grinders is very apparent. At ten or eleven years, used surfaces of the teeth begin to bear a square mark surrounded by a white line, and this is pronounced on all the teeth by the twelfth year; between the twelfth and the fourteenth year this mark takes a round form. [3]
It is a requirement in some locations that prime cattle have a dentition indication mark on them prior to auction. This is normally done by the vendor, or the stock agent. Fat cattle auctions in New South Wales, Australia identify the amount of teeth that prime animals have in the form of sprayed marks along the back. Thus two tooth cattle are marked on the wither, four tooth on the middle of the back and six tooth on their high bone (near tail). Milk and eight tooth cattle are not marked.
The rings on the horns are less useful as guides. At ten or twelve months the first ring appears; at twenty months to two years the second; at thirty to thirty-two months the third ring, at forty to forty-six months the fourth ring, at fifty four to sixty months the fifth ring, and so on. But, at the fifth year, the three first rings are indistinguishable, and at the eighth year all the rings.
The brush of the tail is only useful as a guide when assessing small, stunted or young cattle. A brush that is about fetlock length or longer is an indication that the beast is twelve months old or older. This method cannot be used on cattle which have been bang-tailed. Bang tailing is the act of cutting the long hairs at the tip of the tail short to act as a simple identifier of animals and is commonly used after a procedure has been performed on an individual animal that belongs to a large mob e.g. the mob is run through a race and each animal is vaccinated – immediately after being vaccinated the animal is bang-tailed so they are identified as vaccinated and will not be given a second dose of vaccine. This is useful when large numbers of animals are being processed by a group of individuals.
Cattle age in a carcass is determined checking the physiological skeletal maturity (ossification) (red) of the tips or "buttons" of the thoracic vertebrae. The size and shape of the rib bones are important considerations as well as the colour and texture of the flesh. [4]
The use of number (year) branding, tattoos or ear tags with numbers or different colours are good methods of identifying the age of cattle, if they are used according to standards.
Horse teeth refers to the dentition of equine species, including horses and donkeys. Equines are both heterodontous and diphyodontous, which means that they have teeth in more than one shape, and have two successive sets of teeth, the deciduous and permanent sets.
Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system. Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla or the mandible and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology of the teeth of an animal.
In mammalian oral anatomy, the canine teeth, also called cuspids, dog teeth, eye teeth, vampire teeth, or vampire fangs, are the relatively long, pointed teeth. In the context of the upper jaw, they are also known as fangs. They can appear more flattened however, causing them to resemble incisors and leading them to be called incisiform. They developed and are used primarily for firmly holding food in order to tear it apart, and occasionally as weapons. They are often the largest teeth in a mammal's mouth. Individuals of most species that develop them normally have four, two in the upper jaw and two in the lower, separated within each jaw by incisors; humans and dogs are examples. In most species, canines are the anterior-most teeth in the maxillary bone. The four canines in humans are the two upper maxillary canines and the two lower mandibular canines. They are specially prominent in dogs (canidae), hence the name.
Incisors are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight. Opossums have 18, whereas armadillos have none.
Hypodontia is defined as the developmental absence of one or more teeth excluding the third molars. It is one of the most common dental anomalies, and can have a negative impact on function, and also appearance. It rarely occurs in primary teeth and the most commonly affected are the adult second premolars and the upper lateral incisors. It usually occurs as part of a syndrome that involves other abnormalities and requires multidisciplinary treatment.
Deciduous teeth or primary teeth, also informally known as baby teeth, milk teeth, or temporary teeth, are the first set of teeth in the growth and development of humans and other diphyodonts, which include most mammals but not elephants, kangaroos, or manatees, which are polyphyodonts. Deciduous teeth develop during the embryonic stage of development and erupt during infancy. They are usually lost and replaced by permanent teeth, but in the absence of their permanent replacements, they can remain functional for many years into adulthood.
Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. For human teeth to have a healthy oral environment, all parts of the tooth must develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth week of prenatal development, and permanent teeth begin to form in the twentieth week. If teeth do not start to develop at or near these times, they will not develop at all, resulting in hypodontia or anodontia.
Permanent teeth or adult teeth are the second set of teeth formed in diphyodont mammals. In humans and old world simians, there are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors.
Veterinary dentistry is the field of dentistry applied to the care of animals. It is the art and science of prevention, diagnosis, and treatment of conditions, diseases, and disorders of the oral cavity, the maxillofacial region, and its associated structures as it relates to animals.
In anatomy, a heterodont is an animal which possesses more than a single tooth morphology.
Tooth eruption is a process in tooth development in which the teeth enter the mouth and become visible. It is currently believed that the periodontal ligament plays an important role in tooth eruption. The first human teeth to appear, the deciduous (primary) teeth, erupt into the mouth from around 6 months until 2 years of age, in a process known as "teething". These teeth are the only ones in the mouth until a person is about 6 years old creating the primary dentition stage. At that time, the first permanent tooth erupts and begins a time in which there is a combination of primary and permanent teeth, known as the mixed dentition stage, which lasts until the last primary tooth is lost. Then, the remaining permanent teeth erupt into the mouth during the permanent dentition stage.
Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. Tooth formation begins before birth, and the teeth's eventual morphology is dictated during this time. Dental anatomy is also a taxonomical science: it is concerned with the naming of teeth and the structures of which they are made, this information serving a practical purpose in dental treatment.
Occlusion, in a dental context, means simply the contact between teeth. More technically, it is the relationship between the maxillary (upper) and mandibular (lower) teeth when they approach each other, as occurs during chewing or at rest.
A tooth is a hard, calcified structure found in the jaws of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tearing food, for defensive purposes, to intimidate other animals often including their own, or to carry prey or their young. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of multiple tissues of varying density and hardness that originate from the outermost embryonic germ layer, the ectoderm.
Odontometrics is the measurement and study of tooth size. It is used in biological anthropology and bioarchaeology to study human phenotypic variation. The rationale for use is similar to that of the study of dentition, the structure and arrangement of teeth. There are a number of features that can be observed in human teeth through the use of odontometrics.
Teeth are common to most vertebrates, but mammalian teeth are distinctive in having a variety of shapes and functions. This feature first arose among early therapsids during the Permian, and has continued to the present day. All therapsid groups with the exception of the mammals are now extinct, but each of these groups possessed different tooth patterns, which aids with the classification of fossils.
Serial extraction is the planned extraction of certain deciduous teeth and specific permanent teeth in an orderly sequence and predetermined pattern to guide the erupting permanent teeth into a more favorable position.
Dentition analyses are systems of tooth and jaw measurement used in orthodontics to understand arch space and predict any malocclusion. Example systems of dentition analysis are listed below.
Alveolar cleft grafting is a surgical procedure, used to repair the defect in the upper jaw that is associated with cleft lip and palate, where the bone defect is filled with bone or bone substitute, and any holes between the mouth and the nose are closed.