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1.
Fordyce's granules were observed in the gingiva of the upper incisor and molar teeth in F344 rats. The data were based on 734 males and 722 females that were used as control and treated animals in 26-week, 65-week, and 2-year studies by the National Toxicology Program. The incidence of Fordyce's granules was markedly different when comparing sex, age, and site of the lesion. Fordyce's granules were very common in the midsagittal gingiva of the upper incisor in males and increased in incidence with age (34.2, 50, and 56.3% in 26-week, 65-week, and 2-year studies, respectively). The granules of the incisor gingiva were rare in females (0,0, and 2.8% in 26-week, 65-week, and 2-year studies, respectively). Fordyce's granules of the molar gingiva were very rare in both sexes and were found only in 9/734 (1.2%) males and in 3/722 (0.4%) females. Only three unilateral granules of the molar were grossly recognized as focal swelling of the gingiva or a white nodule with a huge cyst in the third upper molar. Histologically, Fordyce's granules were arranged as a collection of sebaceous glands unassociated with hair follicles. In addition, the granules of the molar gingiva were associated with cystically dilated ducts filled with sebum. Ultrastructurally, the sebaceous cells were characterized by varying numbers of cytoplasmic lipid droplets and occasional desmosome and hemidesmosome formation. Fordyce's granules previously reported in rats of other strains were also reviewed and compared with those in F344 rats in regard to incidence, location, and age.  相似文献   

2.

Objectives

To determine the incidence and rates of progression of gingivitis and periodontitis in Labrador retrievers.

Materials and Methods

Fifty‐three dogs, aged 1·1 to 5·9 years, had their periodontal health assessed every 6 months for up to 2 years. The extent of gingivitis and periodontitis was measured around the whole gingival margin of every tooth under general anaesthesia.

Results

All dogs had gingivitis at the initial assessment. The majority (64·2%) of tooth aspects had very mild gingivitis. The palatal/lingual aspect of all tooth types was most likely to show bleeding when probed: 63·0% of these aspects had mild or moderate gingivitis. Over 2 years, 56·6% of dogs developed periodontitis and dogs as young as 1·9 years were affected. There was a significant positive correlation between the proportion of teeth with periodontitis and age. In total, 124 teeth (5·7%) developed periodontitis; 88 (71·0%) of these were incisors. The palatal/lingual aspect of the incisors developed the disease first (2·8% of incisor aspects).

Clinical Significance

Periodontitis developed in regions that are difficult to see in conscious dogs implying that detection and treatment of disease requires periodic sedation or anaesthesia.  相似文献   

3.
The clinical and microbiological effects of zinc ascorbate gel applied orally in cats were evaluated during a 42-day study period. Cats were divided randomly into two equal groups, with the treatment group (18 cats) receiving zinc ascorbate gel and the control group (18 cats) receiving a placebo (0.9% sterile saline). Clinical parameters evaluated biweekly included halitosis, plaque, calculus, and gingivitis. Aerobic and anaerobic bacterial cultures were obtained from cats in the treatment group at Days 0 and 42. There was a significant decrease in plaque, gingivitis, and anaerobic periodontal pathogens in treatment group cats. Halitosis and calculus scores were not significantly different in treatment group compared with control group cats. The results of this study suggest that zinc ascorbate gel used as an oral antiseptic improves feline oral health, and may be most effective in decreasing bacterial growth, plaque formation, and gingivitis when applied following a professional teeth cleaning procedure.  相似文献   

4.
Several recent studies have reported that alloxan-treated rats with long-term hyperglycemia can develop naturally occurring periodontal disease (PD). Our previous studies detected dental caries in the same model. Therefore, these two lesions of different etiologies are expected to occur concurrently. In this study, we evaluated the use of diabetic rats as a PD model by employing a selective COX-2 inhibitor reported to be effective against PD. Six-week-old female F344 rats were divided into 3 groups: intact rats (control), alloxan-induced diabetic rats fed a standard diet (AL) and alloxan-induced diabetic rats fed a diet containing 0.01% etodolac (AL+Et). The animals were euthanized at 26 weeks of age, and their oral tissues were examined histopathologically. Gingivitis, marginal periodontitis and alveolar bone resorption were markedly enhanced along with dental caries in the AL group compared with the control group. However, the COX-2 inhibitor had no effect on periodontal inflammation in the AL+Et group. In addition, in the AL group, periodontitis was notably nonexistent around the normal molars, and gingivitis was scarcely worse than that in the control group. In the diabetic rats, the progression of periodontal inflammation was closely correlated with the severity of adjacent dental caries, and marginal periodontitis was frequently continuous with apical periodontitis. In conclusion, an alloxan-induced diabetic rat is not a model of PD but of dental caries. It is probable that in this model, hyperglycemia may enable crown caries to progress to apical periodontitis, while the associated inflammation may rostrally expand to surrounding periodontal tissue.  相似文献   

5.
Human or animal hair is considered to be a good indicator of the content of bioelements or toxic elements in human and animal organism. Its analysis is a good alternative for the arduous obtaining blood or biopsy samples. The aim of the performed research was the assessment of some chosen bioelements in the organism of European bison on the basis of their analysis in hair. The investigation material comprised hair samples obtained from 22 animals. All animals were divided into groups according to gender (males, females) and age (calves up to one year of age and animals older than 2 years). Samples were mineralized in nitric acid, under pressure in the microwave apparatus. The content of phosphorus, sulphur, magnesium, iron, titanium and vanadium were determined in hair samples. The content of these elements was determined using the ICP-AES method in accredited laboratory. The accuracy of determinations was tested using the standard reference material. The mean content of phosphorus in hair amounted to 245.14 mg x kg(-1), SD 65.00, magnesium 97.32 mg x kg(-1), SD 33.16, iron 119.48 mg x kg(-1), SD 83.31 and titanium 2.368 mg x kg(-1), SD 2.097. In case of these elements, differences depending on gender and age were statistically insignificant. Mean content of sulphur in the European bison hair amounted to 3.41% with equalized content in the herd (SD 0.22%). Here also statistically insignificant differences depending on gender were observed. However, a statistically significant difference (p < or = 0,05) was demonstrated which depended on animal age. Mature European bisons had more sulphur in hair as compared to calves. The concentration of vanadium (0.362 mg x kg(-1), SD 0.396 on the average) significantly differed in hair depending on the European bison age with much higher values in adult animals (calves 0.260 mg x kg(-1), animals older than 2 years 0.686 mg x kg(-1)). Similar data were obtained while investigating hair of sea mammals.  相似文献   

6.
We induced hypothyroidism in rats by conducting a thyroidectomy (TD) and investigated subsequent changes in the morphology of the skin, especially that of the epidermis and hair follicles. The 6 rats in the TD group seemed less active than the 3 rats in the control group and had cold, dry paws. All of the rats in the TD group exhibited retarded hair growth 12 weeks after surgery. Histologically, all of the rats in the TD group exhibited epidermal thinning from 12 weeks after surgery. Many hair follicles were in the telogen phase: the bulbs and papillae were involuted and had migrated towards the epidermis. Hair follicle atrophy involving thinning of the outer root sheath and the inner root sheath was often observed. The immunoreactivities of antithyroid hormone receptors alpha and beta in the outer root sheaths of 5 of the TD rats were weaker than those of control rats. Cell proliferation in hair follicles of TD rats was weaker than in follicles of control rats 4 weeks after surgery. It is suggested that decreased expression of TRs and decreased cell proliferation activity in the hair follicles of rats is associated with a lack of thyroid hormone and results in retardation of hair growth.  相似文献   

7.
A study to compare the effect of a dental hygiene chew with or without 0.2% chlorhexidine on the development of gingivitis and the accumulation of dental deposits was performed using 11 small dogs. Confirming previous data, the daily addition of a standard chew to a dry diet resulted in significantly less gingivitis and calculus after 3 weeks compared with feeding the dry diet alone. Addition of chlorhexidine to the chew made no difference to the degree of gingivitis or the amount of calculus that accumulated, but did result in significantly less plaque accumulation after 3 weeks. The abrasiveness of the chew, rather than the antibacterial activity of chlorhexidine, is likely to have contributed the most to the maintenance of oral health in dogs with mild gingivitis.  相似文献   

8.
This study was conducted to investigate the effect of sex, age, number of bronchoalveolar lavages and method of quantitation on the number of bronchoalveolar cells in rats. Forty Long Evans rats were divided into four age-sex subgroups of ten animals each. Nine consecutive bronchoalveolar lavages were done in every rat and the number of bronchoalveolar cells/mL in lavages 1-3 (L1), 4-6 (L2) and 7-9 (L3) were determined by hemocytometer and electronic cell counts (Coulter Counter). The sex or age of the rats did not show a significant effect (p less than 0.05) in the number of bronchoalveolar cells recovered from the lungs; however, there was a significant difference (p less than 0.05) in the number of cells/mL among lavages 1-3, 4-6 and 7-9 (L1 approximately equal to L2 greater than L3). A discrepancy of approximately 8% in the counts of bronchoalveolar cells was found between the hemocytometer and the Coulter Counter; however, these two methods of cell quantitation showed a significant (p less than 0.01) positive correlation (r = 0.89). No significant (p greater than 0.05) differences were found in the percentage of fluid recovery (overall mean = 94.5%) among lavages L1, L2 and L3. It was concluded that the electronic cell counting of bronchoalveolar cells is as reliable as manual counting. Although sex or age did not significantly affect the number of cells recovered from the lung, caution should be used in the number of lavages done per rat since this variable may significantly affect the results.  相似文献   

9.
Three breeds of sheep, Southdown, Suffolk and Romney, and two mixed breeds, Border Leicester over Romney and Coopworth over Romney, managed identically on a research station, where they were free from culling and allowed to live their natural life, had their dental configuration examined. The sheep were divided into age groups with 10 sheep in each. The least variation was found in the relation of the upper dental pad to the lower jaw. The most statistically significant differences were found in the first age group: one year six months. The Suffolk breed was noticeably different from the others. Deepened gingival sulci, as well as the inconsistency of bleeding after probing associated with labial gingivitis highlighted the problems of using these latter criteria as indicators of health or disease among sheep on the basis of a single examination.  相似文献   

10.
Periodontal disease is the most common acquired oral disease in cats. It starts with plaque accumulation and gingivitis. The aim of this study was to evaluate the effectiveness of different types of kibble and teeth brushing after professional dental cleaning. To this end, the ratio of facultative anaerobic and obligate anaerobic bacteria was determined, and the amount of plaque and tartar and the severity of gingivitis were measured. Eighty-eight cats with gingivitis and tartar were randomly divided into four groups and given different treatments after professional dental cleaning. The dental treatments were: group 1, cats were fed on small kibbles with mechanical cleaning qualities; group 2, cats were fed on small kibbles without mechanical cleaning qualities, and owners were instructed to brush the cats' teeth; group 3, cats were fed on large kibbles with mechanical cleaning qualities; and group 4, cats were fed on the same kibbles as group 2, but owners were not asked to brush their cats' teeth. A supragingival plaque sample was taken, and used for bacteriological analysis scores for tartar, plaque, and gingivitis were determined at the initial presentation and at 3 and 6 months after professional dental cleaning. Cats fed on the large kibbles with mechanical cleaning qualities (group 3) had significantly less gingivitis and tartar.  相似文献   

11.
The prevalence of odontoclastic resorptive lesions (ORLs) was determined in a clinically healthy cat population (228 cats) using both clinical (oral examination) and radiographic (full-mouth series with intraorally positioned dental film) methods. The overall prevalence rate was 29 per cent (mean age of the cat population 4.9 years). The mandibular third premolars (307, 407) were the most commonly affected tooth and the pattern of ORL development was symmetrical in most cats. The risk of having ORLs was found to increase with increasing age and cats with clinically and radiographically missing teeth were more likely to have the condition. Neutering, gender, age at neutering or mean whole mouth gingivitis index did not affect the prevalence of ORLs.  相似文献   

12.
Despite several inherent characteristics that would appear to make hair a useful biopsy tissue, many problems make interpretation of data derived from hair analysis difficult. Endogenous minerals are incorporated into hair by several routes. Most attention on hair mineral incorporation has focused on element uptake within the hair follicle. Minerals incorporated within the follicle are presumably chemically or physically associated with cortical cells of the hair shaft and reflect mineral status at the time that the hair filament was synthesized. Because hair follicles in most species regularly go through cycles of intense metabolic activity and quiescence, mineral incorporation through the follicle is not a continual process. Mineral deposition onto hair does not cease when the follicle is not producing a hair fiber. The hair shaft is continuously exposed to several elements through contact with secretions from sebaceous, apocrine and eccrine glands. Significant quantities of major and trace elements of endogenous origin are adsorbed onto the hair surface via these secretions, especially when hair growth is not occurring or is very slow. For several elements significant correlations exist between mineral concentrations in hair and mineral intake. These correlations, however, are usually quite low. Non-dietary factors such as sex, age, hair color, sire, body location and contamination affect mineral levels in hair. Dietary intake of calcium, phosphorus and iron are also known to affect uptake of other elements in hair. Because many factors cause variation in mineral content in hair, hair analyses are not precise indicators of mineral status. Hair mineral analyses may be useful, however, when combined with other indicators of mineral status to provide a more precise assessment of mineral status in livestock.  相似文献   

13.
Large-bodied Demodex mites were detected in 4 dogs. The mites were readily detected in material obtained via deep skin scrapings and were most commonly found on the trunk. The mites were distinguishable from D. canis, because adult males were approximately 100% longer and adult females were approximately 50% longer than adult male and female D. canis mites, respectively. The large-bodied mites were found in the hair follicles, sebaceous ducts, and sebaceous glands in histologic sections of skin from 2 dogs. All dogs had adult-onset generalized demodicosis. Two dogs had coexistent iatrogenic hypercortisolism, 1 dog had hypothyroidism, and 1 dog did not have coexistent disease. Infestations responded to miticidal therapy, control of the coexistent disease, or both.  相似文献   

14.
为了获得羊驼Bclaf1基因cDNA序列,研究该基因在羊驼皮肤中的表达特征.本研究对已构建的羊驼皮肤cDNA文库进行筛选和ESTs分析,并运用免疫组化技术对Bclaf1在羊驼皮肤中的表达进行组织定位.结果,羊驼Bclaf1基因与褐鼠、小鼠、狗、人和黑猩猩Bclaf1基因相应cDNA序列的相似性分别为100%,92.9%、86.0%、81.1%和77.9%.Bclaf1在幼年羊驼毛囊中没有阳性细胞,在成年羊驼、白色和棕色羊驼毛囊的外根鞘处集中表达;根据光密度值分析得Belaf1在不同毛色羊驼毛囊中的表达差异显著.结果表明,Betaf1基因在羊驼皮肤中的表达和定位随年龄和毛色而变化.  相似文献   

15.
The objective of this study was to investigate the presence of Toxocara eggs on the hair of stray cats. The total number of stray cats trapped and included in the trial was 167 that were collected weekly from different residential areas of Mashhad, in northeastern Iran, from November 2016 to December 2017. Among the 167 cats, 18 (10.8%) of them were positive to T. cati eggs in their hair. In the positive cats, 7 (39%) were adult, 1 (6%) was juvenile and 10 (55%) were kittens. Overall, the mean number of eggs from positive cats was 3.9 ± 1.7 eggs per gram (epg) of hair per cat with an average of 3.1 ± 1.4 in adults, 4.9 in juveniles and 4.3 ± 1.6 in kittens. In total, 39.9% of the eggs recovered were non-viable 35.5% were viable, 22.2% were embryonating and 2.3% were embryonated which embryonated eggs were found only in juveniles. Based on our data, kittens were responsible for 61.7% of the total number of eggs. The age of the cat was found to be an important risk factor associated with parasitic infection.. This study showed that cat hair contaminated by T. cati eggs in different developmental stages represents of potential source for human toxocariasis.  相似文献   

16.
The use of hair as a sample matrix to determine the mineral status of an animal has received a lot of interest. The objective of this study was to determine if the trace element content in horse mane hair changed with age when evaluated in a group of horses representing a large age range. As a second objective, whole blood trace element content was evaluated, and its relationship to mane hair trace element content, as well as age, were tested. Therefore, mane hair and whole blood samples were obtained from 59 horses, ranging from 2 months to 26 years in age, housed on the same farm. Mane hair samples were washed, and hair and blood digested and analyzed for 11 trace elements. Weak correlations (P < .05) between age and mane hair trace element content was detected for arsenic (r = 0.29), copper (r = −0.39) and selenium (r = −0.27). While the mane hair color did not affect trace element concentration, greater variability was detected in the black mane hair samples. This resulted in outliers that were removed from the final statistical analysis. However, data is presented to the reader both ways. Correlations were also detected (P < .05) between age and whole blood iron (r = 0.62), selenium (r = 0.76) and zinc (r = 0.47). This is similar to what has been reported in horses using serum or plasma. The trace element concentrations of mane hair and whole blood were not correlated (P > .05) in this study. However, the concentrations of trace elements in mane hair were higher than that of blood. Trace elements, specifically chromium and lead, that were below detection levels in the blood, were detectable in mane hair. This suggests that mane hair may be a potential means to investigate suspected exposure to excessive levels of trace minerals or heavy metals that are difficult to detect in blood.  相似文献   

17.
为了解水貂皮肤毛囊发育的变化规律,本试验采集0~6周龄初生的美国短毛黑公水貂的背中部皮肤样品,用HE染色法制备组织切片,在显微镜下观察其皮肤毛囊结构及变化规律。结果发现,水貂的皮肤在出生前就已经基本发育完成,初级毛囊、次级毛囊的毛干具有髓质;水貂出生时可见初级毛囊而无次级毛囊,初级毛囊的密度随周龄的增加而增加,于4周龄后降低,初级毛囊在水貂4周龄后不再发育或很少发育, 4周龄时可见次级毛囊,次级毛囊随水貂体表的增长毛密度增加,且在水貂出生后大量发育。水貂6周龄时S/P值为2.95±0.23,次级毛囊仍将大量发育。水貂背中部表皮呈先增厚后变薄的变化,真皮随着周龄的增加而增厚;初级毛囊、次级毛囊随周龄的增加而加深。  相似文献   

18.
本文旨在研究母兔妊娠期饲粮蛋氨酸水平对仔兔毛囊发育的影响.选择体重、胎次和历史产毛量相近的健康长毛兔母兔54只,随机分为3组,每组18个重复,每个重复1只.妊娠期各组分别饲喂蛋氨酸水平为0.51%、0.71%和0.91%的饲粮.测定18胎龄、26胎龄、初生和2月龄时仔兔背部皮肤毛囊密度、直径以及2月龄时毛纤维直径.结果...  相似文献   

19.
The purpose of the study was to evaluate intermediate adrenal steroid hormones (ISH) in neutered dogs with hair cycle arrest (Alopecia X) during treatment with melatonin, and to see if hair re-growth is associated with sex hormone concentrations within the normal ranges. Twenty-nine neutered, euthyroid, and normo-cortisolemic dogs were enrolled in the study (23 Pomeranians, three keeshonds, two miniature poodles, and one Siberian husky). Coat assessment and an ACTH stimulation test were performed pre-treatment and approximately every 4 months for a year post treatment. Melatonin was administered initially at 3-6 mg, every 12 h. Based on clinical progression, each dog was continued on the current dose of melatonin, given an increased dose of melatonin or changed to mitotane. Partial to complete hair re-growth occurred in 14/23 Pomeranians, and partial re-growth in 3/3 keeshond and 1/2 poodle dogs. A Siberian husky dog failed to re-grow hair. Fifteen dogs had partial hair re-growth at the first re-evaluation. Melatonin dosage was increased in eight dogs but only one had improved hair re-growth. On mitotane treatment, partial to complete hair re-growth was seen in 4/6 dogs and no re-growth in 2/6 dogs. No significant decrease in sex hormone concentrations were seen during melatonin or mitotane treatment. Concentrations of ISH in dogs with hair re-growth did not differ significantly from pre-treatment values. At the completion of the study, androstenedione, progesterone and 17-hydroxyprogesterone were still above reference ranges in 21, 64 and 36%, respectively, of dogs with partial to complete hair re-growth. In conclusion, 62% of dogs had partial to complete hair re-growth. However, not all dogs with hair re-growth had concentrations of ISH within the normal range.  相似文献   

20.
Two-hundred shelter cats from the Pacific western coastal USA were sampled in four different geographical regions to determine the fungal organisms most commonly found on the hair coat and the prevalence of these organisms. Data on the cats' health, age, hair coat length, gender, and geographical location were collected and analysed. The overall prevalence of dermatophytosis was 5.5% (11 of 200 cats), with Microsporum canis isolated in 90.9% (10 of 11) of the samples from positive cats. This was a lower isolation rate or prevalence of dermatophytes than previous studies conducted on shelter cats in other regions of the USA. Ten of 11 of the cats were lesion free (either subclinical infection or mechanical carriage). Cats in the Los Angeles, California area ( P  = 0.001) and neutered male cats ( P  = 0.047) had a higher prevalence of a positive dermatophyte culture. The numbers and types of saprophytes isolated from cats in this study were found to be consistent with previous feline reports in the USA and with an equine study previously conducted in this area.  相似文献   

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