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1.
Chronic fluoride toxicity in the form of osteo-dental fluorosis was observed in cattle, buffaloes, sheep and goats from 21 villages of Banswara, Dungarpur and Udaipur districts of Southern Rajasthan where the mean fluoride concentration in drinking water varied from 1.5 to 4.0 ppm. The prevalence of dental fluorosis in calves (<1 year age) was greater than that in adult cattle and buffaloes. At a fluoride concentration in the water of 4.0 ppm, 100% of calves, 65.6% of buffaloes and 61.0% of cattle were found to be affected with dental fluorosis to varying degrees. In the older group of buffaloes, their teeth were brownish black instead of creamy yellow as found in calves and cattle. Out of 780 goats and 564 sheep, none revealed evidence of osteo-dental fluorosis. The overall prevalence of skeletal fluorosis was 8.5%, with the highest prevalence of 29.0% in cattle and 37.5% in buffaloes at a fluoride concentration of 3.2 ppm. None of the calves were affected with skeletal fluorosis. Intermittent lameness was observed in the older group of animals (>7 years age) at 2.8 ppm fluoride or more in the water. None of the fluorotic animals exhibited any apparent evidence of hypothyroidism, stunted growth or low milk production. There was no correlation between gender and the prevalence of fluorosis, but the prevalence and severity of skeletal fluorosis increased with increasing fluoride concentration and age. Possible factors causing variation in fluorosis in the cattle and buffaloes in villages with identical fluoride concentrations are discussed.  相似文献   

2.
Deciduous incisors from calves born to dams fed an average of 40 mg of fluoride/kg of forage ration (40 ppm) were compared with incisors from calves born to dams fed a normal dairy ration. Skeletal fluoride concentration in the calves born to fluoride-fed dams was increased 5 to 8 fold, but enamel mottling and hypoplasia, typical of permanent bovine incisor dental fluorosis were not seen by gross, histologic, or radiologic examination. Decreases in the amount of enamel on the tooth or hardness of the enamel were not observed. These data do not support recent reports of widespread dental fluorosis of deciduous bovine teeth as a clinical sign of fluoride toxicity.  相似文献   

3.
Peripheral caries (PC) is an increasingly recognised equine dental disorder with unknown predisposing factors that differs from the well described maxillary cheek teeth infundibular caries. Advanced PC can lead to premature wear and fracture of cheek teeth and thus is of welfare importance. Recent studies have shown large variation in the prevalence of PC in different European countries, with a trend towards a greatly increasing prevalence. One hundred and one equine heads sourced from a Scottish rendering plant were examined for the presence and grade of PC using the modified Honma equine dental caries grading system. The presence of cheek teeth calculus, diastemata and fractures was also recorded. Peripheral caries was present in 91% of horses; only affected the cheek teeth and was predominantly (72.6%) Grade 1 Class 1 (localised pitting lesions only affecting cementum). The caudal three cheek teeth were more commonly affected (74.7% prevalence) as compared to the rostral three cheek teeth (32.1% prevalence). The palatal aspect of maxillary and the buccal aspect of mandibular cheek teeth were significantly (245% and 170%, respectively) more commonly affected by PC than the opposite sides. Female horses were more commonly affected than males. Because post-mortem examination allows the most detailed oral examination to be performed, this may partly explain the higher PC prevalence found in the current, as compared to previous studies, in addition to the particular population examined in this study.  相似文献   

4.
氟中毒对动物健康影响的研究进展   总被引:3,自引:1,他引:2  
研究证实慢性氟中毒不仅影响了动物骨骼和牙齿的形状和结构,使牙齿断裂和脱落甚至诱发骨癌,而且还对胃肠道、肝、肾和脑等软组织的结构和功能具有不同程度的影响,氟中毒还影响了动物的生殖系统。其中毒机理的研究表明:过量氟可导致机体自由基代谢紊乱以及脂质过氧化作用的增强,并降低机体的免疫功能。  相似文献   

5.
Bovine dental fluorosis: histologic and physical characteristics   总被引:2,自引:0,他引:2  
Incisor teeth from 5- to 6-year-old Holstein-Friesian cattle maintained on a ration averaging 40 ppm F annually from 4 months of age were analyzed by a variety of histologic techniques. These techniques included photomicroscopy, microradiography, protein staining, and microhardness testing. The features of fluorotic enamel that were noted were: hypomineralized outer enamel, coronal cementum hyperplasia, disrupted subsurface pigment band, hypoplastic pits, puckered incremental lines, periodic radiolucent regions, positive protein staining, and decreased microhardness of the outer enamel. These results were similar to the lesions of dental fluorosis observed in other species, and explain the external appearance of fluorotic bovine teeth observed under field conditions.  相似文献   

6.
The main objective of this study was to evaluate an endoscopic examination protocol for routine dental examination in horses. The oral cavities of 300 standing, sedated horses were examined under field and hospital conditions with a rigid endoscope using a standardised technique that included examination of the occlusal, lingual (palatal) and buccal surfaces of all cheek teeth rows. The most common cheek teeth abnormalities detected were sharp enamel edges (present in 96.3% of horses), focal overgrowths (64.3%), fissure fractures (54.3%), diastemata (24.3%) and infundibular hypoplasia/caries (48.3%). Rigid endoscopy of the equine oral cavity was found to be a safe non-invasive diagnostic technique that appeared to be superior to clinical oral examination for detecting subtle cheek teeth changes.  相似文献   

7.
The oral and intra-osseous development of each of the six manidibular cheek teeth found in the permanent dentition of cattle was studied. The animals used were all British Friesians, of varying sex, and slaughtered at different weights at ages between 13 and 22 months. The various stages of development observed in each tooth together with the mean age and age range at which they were seen are recorded. Significant differences were found between the ages at which several of the developmental stages were seen in most of the teeth and indicated that tooth formation in the Friesian cattle studied tended to fall within well defined age limits.  相似文献   

8.
The angle between the occlusal surface of the tooth and the horizontal plane of 687 cheek teeth from the skulls of 22 horses without gross dental disorders and 11 horses with dental disorders were measured by using stiff malleable wire as an imprint. Each measurement was repeated five times and the mean angle was recorded. In the normal skulls, the mean occlusal angles of the mandibular cheek teeth ranged from 19.2 degrees at the Triadan 06 position to 30 degrees at the 11 position, and these angles were significantly greater than the occlusal angles of the opposing maxillary cheek teeth (range 12.5 degrees to 18 degrees) at all the positions except the 06. The rostral mandibular cheek teeth had significantly lower occlusal angles than the caudal mandibular cheek teeth, but the converse was true for the maxillary teeth. In the skulls with dental disorders the occlusal angles of the mandibular cheek teeth ranged from 15.6 degrees to 28.5 degrees , and of the maxillary cheek teeth from 9.2 degrees to 16.4 degrees. They were not significantly different from the angles of the teeth from the normal skulls, except at the 06 position, where they were smaller.  相似文献   

9.
Two hand rasps (tungsten chip blade, solid carbide blade) and an electrically-driven solid carbide axial bur were used to treat the cheek teeth of 2 horses immediately postmortem. All teeth were normal and were rasped to a standard considered satisfactory in practice. Six teeth from each horse served as untreated controls. Following treatment, the teeth were extracted and the clinical crown removed and prepared for scanning electron microscopy. Teeth were also extracted and examined from a horse that had excessive dental treatment previously. Dental debris created by the procedures was collected and examined. All three rasp techniques resulted in amputation of odontoblast processes. The solid carbide blade cut deep gouges and grooves into the surface of the dentin, chipping the enamel and peripheral cement. No smear layer was created. Rasping with a tungsten chip blade created a partial smear layer and a smoother surface than the solid carbide blade. The electrically-driven bur produced a complete smear layer and removed all dental tissues to a smooth layer. The enamel had also been damaged by the electric bur. Crown particles collected after the procedures were larger following hand rasping compared with particles produced by the electric bur. The extent of damage to sensitive and vital dentin tissue was of concern. Further studies are required to establish the optimum technique for rasping equine cheek teeth.  相似文献   

10.
The impact of pelleted diets with different mineral compositions on the crown size of the mandibular cheek teeth, as well as the mandibular bone and cheek teeth density, in degus (Octodon degus) was investigated. A total of 28 animals were randomly divided into four groups and fed different calcium or phosphorous dietary content, in the presence or absence of UV light, for 14 months. Dental radiographs and CT images of the head were taken, and the crown size of premolar and molar teeth was recorded. Apical and coronal crown elongation of all cheek teeth and significantly smaller relative cheek teeth and mandibular densities were recorded in degus fed a high-phosphorus diet with an improper calcium:phosphorus ratio. A diet with a calcium:phosphorus ratio of 1:1 was also responsible for the rapid development of dental disease with subsequent severe health impairment.  相似文献   

11.
工业氟污染对小尾寒羊牙齿和骨骼中氟含量的影响   总被引:1,自引:1,他引:0  
韩天龙  王敏 《中国畜牧兽医》2010,37(10):226-228
于工业氟污染区选取4只雌性氟斑牙小尾寒羊作为试验组,于氟安全区另选4只健康小尾寒羊作为对照组;分别采集其肋骨及牙齿,利用氟离子选择电极法测定了其骨氟及牙氟含量。结果表明,氟污染区小尾寒羊的骨骼和牙齿中氟含量均明显高于氟安全区,差异极显著(P<0.01);氟污染区骨氟含量较对照组相对增长了73.5%;试验组牙氟含量较对照组相对增长了161.6%;表明氟在牙齿中的蓄积程度高于骨骼。本试验为进一步研究氟中毒对牙齿和骨骼的损伤机理奠定基础。  相似文献   

12.
Of 400 referred horses with dental disorders, 349 cases suffered from primary disorders of their cheek teeth, ninety of these from disorders of development or eruption, or displacements. These included 20 cases with rostral maxillary and caudal mandibular cheek teeth overgrowths, 16 with diastemata, 15 with grossly enlarged mandibular 'eruption cysts', 4 with grossly enlarged maxillary cheek teeth 'eruption cysts', 10 cases with supernumerary cheek teeth and 23 cases with displaced cheek teeth. These displacements were believed to be developmental in 16 cases and acquired in the remaining 7 cases. Long-term response to treatments, that included removal of overgrowths and extraction of teeth with deep secondary periodontal disease was excellent for most disorders except diastemata.  相似文献   

13.
Reason for performing study: Fissures of the occlusal surface of the equine cheek tooth are poorly understood and their association with dental disease is unknown. Objective: To describe the prevalence and location of occlusal fissures in the cheek teeth (CT) of a group of horses referred for dental investigation/treatment, and determine association with intercurrent dental disease. Methods: Digital video recordings of oral endoscopic examinations for all horses referred to the Rossdales Equine Hospital for dental investigation from November 2006 to June 2009 were reviewed. Location of occlusal fissures in relation to both Triadan tooth position and pulpar secondary dentine was recorded; direction of fissure and concurrent involvement of enamel was also documented. The CT location considered at the time of examination to be the primary site/s of disease was correlated with presence of fissures on these teeth. Results: 91 cases meeting the inclusion criteria were identified. Occlusal fissures were documented in 58.2% (53/91) cases, with a total of 227 CT being affected. Fissures were most prevalent mid‐arcade. The majority (92.1%) of fissures in maxillary CT were associated with the caudal palatal pulp horn. Fissures in mandibular CT were predominantly associated with the buccal pulp horns (95.7%). There was no significant difference in the median number of CT with fissures in relation to gender. There was no correlation between age (r2= 0.01) of horse and number of CT with fissures. A significantly greater number of CT with multiple occlusal fissures was found in mandibular compared to maxillary arcades. No correlation was found between presence of fissures and location of individual CT considered to be primarily responsible for presentation. Conclusions: Occlusal fissures in this group of animals were common and not correlated to primary site of dental disease. Potential relevance: In horses subjected to dental investigation, occlusal fissures of the cheek teeth should not be considered an indicator of tooth compromise. Location and direction of fissure propagation in most cases is inconsistent with occlusal fissures being causally implicated in slab fractures of cheek teeth, although site predilection may indicate a possible association with masticatory forces.  相似文献   

14.
The effects of fluoride ingestion (3.5 mg/kg of body weight) were evaluated in 9 ewes at 6 through 9, 10 through 13, or 14 through 17 months of age (3 ewes/age group). In the 3 groups, the plasma fluoride concentration rapidly increased to 0.45, 0.46, and 0.50 microgram/ml, respectively, and decreased rapidly to 0.1 microgram/ml after fluoride was removed from the ration. In 5 of the 9 ewes, this short-term exposure caused symmetrical, moderate damage to the molars, which is characteristic of fluorosis in sheep. In 7 of the 9 ewes, abnormal gaps were found between incisors, which are not characteristic of fluorosis in sheep. Fluoride accumulation was higher in the roots of the incisors and in the dentine of the molars and was particularly evident in teeth that were developing when fluoride was administered; however, the fully developed teeth and teeth that developed several months after administration of fluoride also were affected. The increase in fluoride concentration in the enamel was confined to a maximum of 2 molars. The abnormal wear of the molars was not directly linked to fluoride accumulation.  相似文献   

15.
Polyodontia is defined as the presence of teeth in excess of the normal dental formula. In equids, supernumerary teeth are uncommon but, when present, are usually located mainly in the caudal aspects of the cheek teeth rows (distomolars), also being found adjacent to normal cheek teeth or even in an ectopic location. It is believed that this disorder is a result of an inappropriate differentiation of dental germinal tissue during gestational development, with external trauma also acting as an initiating factor, when teeth germs are affected. The presence of these abnormal teeth can lead to axial displacement, dental overgrowths, dental‐related soft tissue damage, diastemata formation, periodontal disease and development of secondary sinusitis. A large prospective, cross‐sectional study was performed in 800 donkeys, with the aim to investigate the prevalence and aetiopathogenesis of clinically diagnosed oral and dental disorders. Polyodontia was recorded in 2.25% of the donkeys, presenting 36 supernumerary teeth, with 2.80% being incisors and 97.20% cheek teeth, with prevalence increasing with age. The caudal aspects of the maxillary cheek teeth rows were the most common locations for supernumerary teeth development (distomolars). The mandible was far less commonly affected than the maxilla. Although polyodontia is uncommon in donkeys, it should be considered in the differential diagnosis of dental disease. A methodical oral examination and a complete radiographic survey of the entire dental arcades are crucial for a correct early diagnosis and treatment plan implementation. The increasing prevalence of fully erupted supernumerary teeth recorded in older groups suggested a late onset eruption process, and therefore, in donkeys undergoing regular dental prophylaxis, the presence of previously unnoticed supernumerary teeth should always be sought.  相似文献   

16.
Reasons for performing study: Removal of cheek teeth in all but the aged horse or pony is a serious undertaking with potentially deleterious sequellae. Rigid endoscopy permits detailed examination of the oral cavity and erupted dental tissues and has the potential to assist in the correct identification of the diseased tooth. Objectives: To document oral endoscopic findings associated with infected equine cheek teeth in cases without gross oral pathological changes and thereby determine the usefulness of rigid oral endoscopy as an aid to diagnosis of such infections. Methods: Records of all cases of equine cheek tooth removal attempted under standing sedation over a 38 month period were examined. Cases were excluded from the study if apical infection was associated with gross dental fracture, malalignment, diastema/periodontal pocketing or supernumerary teeth. Endoscopic and radiographic findings were analysed and correlated to diseased tooth location. Results: Seventeen cases of apical dental infection fitting the inclusion criteria (nonresponsive to antibiotics and with no gross oral abnormality of the affected arcade) were identified in which oral endoscopy was used as an aid to diagnosis. In 15 (88%) of the 17 cases, oral endoscopy revealed abnormalities specific to the infected tooth. Focal gingival recession (10/17 cases) was the most common visible abnormality associated with infected teeth. Conclusions: In the majority of cases of apical infection of equine cheek teeth there is visible intraoral evidence implicating the affected tooth. Potential relevance: Oral endoscopy facilitates detailed examination of the mouth and should be considered along with radiography as an important aid to diagnosis in cases of equine dental infection.  相似文献   

17.
18.
Due to their long hypsodont reserve crowns, extraction of equid cheek teeth can be difficult and result in more complications than the extraction of their shorter brachydont counterparts although the more recent resumption of oral extraction has greatly reduced such complications. The more common post-extraction sequelae in equids include non-healing alveoli due to retained dental or alveolar sequestrae which may lead to oromaxillary or oronasal fistula formation, chronic external sinus tract formation or osteomyelitis of the supporting bones. Collateral damage to adjacent teeth has also occasionally been reported during dental repulsion. Systemic complications following equine cheek tooth extraction have been infrequently described, including a small number of cases of exodontia-related bacterial meningioencephalitis. This is surprising, as dental manipulation can lead to bacteraemia in many species, including horses. Infections at distant sites related to the spread of dental pathogens have been well described in humans and in small animals. This report describes deep abscessation of the masseter muscles followed by extensive thrombophlebitis of the jugular, facial and rostral cervical veins following oral cheek tooth extraction in a pony affected by pituitary pars intermedia dysfunction (PPID) that was successfully treated by abscess drainage and thrombectomy of the affected veins.  相似文献   

19.
Fluoride intoxication in dairy calves   总被引:2,自引:0,他引:2  
Chronic fluoride intoxication in dairy cattle, caused by feeding fluoride contaminated commercial feed, was previously described in a dairy herd. Dental fluorosis and a catastrophic decrease in milk yield were the foremost findings. In calves born to the fluoride intoxicated cows, congenital fluorosis was manifested by brown discoloration of enamel, enamel hypoplasia, brown mottling of bone, severe retardation of cartilage cell differentiation, atrophy of osteoblasts, osteopenia, atrophy of bone marrow cells, serous atrophy of bone marrow fat and severely stunted growth.  相似文献   

20.
氟是动物机体的必需微量元素,适量的氟有利于骨骼、牙齿的生长,过量的氟则会引起机体慢性全身性中毒,主要影响骨骼、牙齿的正常生长,另外对消化系统、生殖泌尿系统、神经系统、内分泌系统和免疫系统也产生中毒影响。作者从氟中毒机制的国内外研究现状和进展出发,就过量氟化物对动物机体的影响进行综述,以期为动物氟中毒病相关研究提供参考。  相似文献   

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