Significant association between tooth extrusion and tooth resorption in domestic cats     

Lewis JR  Okuda A  Shofer FS  Pachtinger G  Harvey CE  Reiter AM 《Journal of veterinary dentistry》2008,25(2):86-95

Abnormal extrusion of canine teeth is often noted in middle-aged and geriatric domestic cats. The same age group of cats also is commonly affected by tooth resorption (TR). This study explored the relationship between these two phenomena of unknown etiology. Using digital radiography, the distance between the alveolar margin (AM) and cementoenamel junction (CEJ), referred to as the AM-CEJ distance, was measured in clinically and radiographically healthy maxillary canine teeth of 24 TR-affected and 29 TR-free cats. The mean AM-CEJ distance of maxillary canine teeth of cats with and cats without TR was 2.68-mm and 2.22-mm, respectively. An analysis of covariance adjusting for age revealed a significant correlation (p = 0.02) between tooth extrusion and TR. Extrusion of the maxillary canine teeth became clinically apparent when an AM-CEJ distance of 2.5-mm or greater was evident in the absence of horizontal or vertical alveolar bone loss. Based on this criterion, 15 of 24 cats with TR (63.0 %) exhibited extrusion of maxillary canine teeth, compared to 9 of 29 cats without TR (31.0 %). Four extruded and five non-extruded maxillary canine teeth were evaluated histologically. Cementum of extruded teeth was significantly thicker compared to that of non-extruded teeth. Four of 4 canine teeth with extrusion (100 %) showed histological evidence of resorption, compared to 1 of 5 canine teeth without extrusion (20.0 %). These results suggest that tooth extrusion is linked to or may be caused by similar factors responsible for the development of TR.  相似文献   

Mitochondrial Activity, Distribution and Segregation in Bovine Oocytes and in Embryos Produced in Vitro   总被引：7，自引：0，他引：7  

AM Tarazona  JI Rodríguez  LF Restrepo  M Olivera-Angel 《Reproduction in domestic animals》2006,41(1):5-11

Contents Bovine oocytes and embryos produced in vitro were studied to determine the mitochondrial pattern of distribution, segregation and activity using DIOC 6 and Jc-1 fluorescence. The highest fluorescence level observed in mature oocytes was taken as 100% activity and six activity levels were estimated as follows: (1) 0%, (2) 1-15%, (3) 16-30%, (4) 31-50%, (5) 51-75% and (6) 76-100%. Three patterns of mitochondrial distribution were found: (1) diffused throughout the cytoplasm in oocytes and embryos, (2) pericytoplasmic in oocytes and embryos, and (3) perinuclear only in embryos. The segregation of mitochondria in blastomeres showed two distinct patterns: (1) symmetrical with an even mitochondrial population, and (2) asymmetrical with different numbers of mitochondria in each blastomere. In immature oocytes, mitochondrial activity was very low and the distribution was diffuse or negligible, while in mature oocytes the activity was high and the distribution was diffuse or pericytoplasmic. Competent embryos up to the 16-cell stage showed intermediate levels of activity (16-50%) but activity decreased thereafter up to the blastocyst stage. Non-competent embryos showed low levels of activity (1-15%) at all stages. These results suggest that mitochondria might play an important role during early development and that a minimum threshold of activity regulates the potential competence for reaching the blastocyst stage.  相似文献   

Shearing male lambs in the cold season improves the carcass yield without affecting fattening performance   总被引：1，自引：0，他引：1  

Mehmet Akif ÇAM  Mustafa OLFAZ  Ali Vaiz GARIPOGLU 《Animal Science Journal》2007,78(3):259-265

This research was carried out to determine the effects of shearing of different genotypes of male lambs (one from pure Karayaka stock and two from its crossbreed) in winter on bodyweight gain, feed consumtion, feed conversion efficiency, rectal temperature and carcass yield. A total of 21 lambs aged 8 months were allocated randomly to experimental groups according to a 2 × 3 factorial arrangement for shorn and unshorn animals. The lambs were fed grass hay (100 g/lamb/day) and commercial concentrate feed ad libitum during a 54‐day of fattening period. The lambs were shorn in the middle of the experiment (27 days after beginning the trial). The interaction between the shearing treatment × genotype of the studied parameters was found to be insignificant. The shearing process increased the rectal temperature (P < 0.01), hot carcass yield (P < 0.05) and dressing percentage (P < 0.05) and decreased the weight of the edible inner organs (P < 0.01). Some of these parameters were affected by the genotypes. It was concluded that shearing male lambs in the winter can have a beneficial effect on the hot carcass weight and dressing percentage without affecting fattening performance, and the performance of Karayaka lambs and its crossbred male lambs were similar under the conditions of the present study.  相似文献   

Assessment of the potential of dogs and cats as urban reservoirs of Ross River and Barmah Forest viruses     

AM BOYD  BH KAY 《Australian veterinary journal》2002,80(1):83-86

Objective To determine whether dogs and cats are potential reservoirs of Ross River (RR) and Barmah Forest (BF) viruses
Method Young seronegative female dogs and cats were experimentally exposed to the viruses using Ochlerotatus vigilax (Skuse) mosquitoes.
Results Only one of the 10 dogs and one of the 10 cats exposed to RR developed neutralising antibody. None of the animals developed detectable viraemia or clinical signs. One dog and three cats exposed to BF developed neutralising antibody. In addition, a serological survey of sera obtained from domestic dogs and cats residing in the Brisbane region indicated that 23.7% and 1.3% of dogs, and 14% and 2% of cats, had neutralising antibodies to RR and BF respectively.
Conclusions Although dogs and cats are exposed naturally to these viruses, and can become infected, they are unlikely to be important urban reservoirs of either virus.  相似文献   

Scanning electron microscopy of the superficial pineal gland of the 15-day-old rat (Rattus norvegicus)     

Ortiz GG  García JJ  Feria-Velasco A  Rosales-Corral SA  Reiter RJ 《Anatomia, histologia, embryologia》2004,33(3):158-160

The presence of a cortex and medulla in the superficial pineal gland has been a controversial point in the morphology of this structure in mammals. The published reports indicate contradictory data especially in rodents. In this study the pineal gland of 15-day-old male rats (Rattus norvegicus) were studied, using scanning electron microscopy, in an attempt to determine whether or not a cortex and medulla are apparent in the pineal gland of young rats. The superficial pineal gland of the 15-day-old rat exhibited both a cortex and a medulla; these areas exhibited different structural organizations. The cortex had a thickness of 40-80 microm and the cells did not show a particular arrangement. The center of the gland was composed of a medulla, which had a width of 1000-1200 microm, and consisted of cells arranged in cords; its morphology was distinctly different from that of the cortex.  相似文献   

Local and systemic complications in a cat after poorly performed dental extractions     

Reiter AM  Brady CA  Harvey CE 《Journal of veterinary dentistry》2004,21(4):215-221

This case report describes a cat that was presented with infected oral tissues and signs of systemic inflammatory response. Incomplete dental extractions had been performed 10-days earlier During a second dental procedure, 22 tooth root remnants were removed. Diabetic ketoacidosis and possible thromboembolism complicated the cat's recovery period After 13-days of hospitalization, the patient was stable enough to be sent home. Postoperative examinations at 1, 3, 6, 12, 16, 24, and 52-weeks indicated continued improvement with moderate glycemic control and chronic but stable renal failure. The patient died from further complications of diabetic ketoacidosis 20-months following root remnant extractions.  相似文献   

Effect of Stressors on Ova Transport in the Pig     

AM Mwanza  P Englund  S Einarsson  H Kindahl 《Reproduction in domestic animals》2000,35(3-4):188-189

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Perth 2000 AGM date     

Bill Gee AM 《Australian veterinary journal》2000,78(3):141-141

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Pineal gland: influence on gonads of male rats treated with androgen 3 days after birth   总被引：1，自引：0，他引：1  

R J Reiter  J C Hoffman  P H Rubin 《Science (New York, N.Y.)》1968,160(826):420-421

Either blinding or the injection of 1 milligram of testosterone propionate into male Sprague-Dawley rats, 3 days old, results in testes and accessory organs (seminal vesicles and coagulating glands) that are smaller than normal when the rats are 72 days old. The response to blinding is prevented by removal of the pineal gland, whereas the response to treatment with testosterone is unaffected by pinealectomy. Combination of the two treatments in 3-day- old rats causes testes to be less than one-third their normal size at 72 days of age; pinealectomy in these rats permits the reproductive organs to grow to the same size as those in the androgen-treated animals.  相似文献   

Giant Piezoelectric Effect in Strontium Titanate at Cryogenic Temperatures     

DE Grupp  AM Goldman 《Science (New York, N.Y.)》1997,276(5311):392-394

Piezoelectric materials have many applications at cryogenic temperatures. However, the piezoelectric response below 10 kelvin is diminished, making the use of these materials somewhat marginal. Results are presented on strontium titanate (SrTiO3), which exhibits a rapidly increasing piezoelectric response with decreasing temperature below 50 kelvin; the magnitude of its response around 1 kelvin is comparable to that of the best materials at room temperature. This "giant" piezoelectric response may open the way for a broad class of applications including use in ultralow-temperature scanning microscopies and in a magnetic field-insensitive thermometer. These observations, and the possible divergence of the mechanical response to electric fields at even lower temperatures, may arise from an apparent quantum critical point at absolute zero.  相似文献