Search PubMed⌕ Search

Biomedical subjects

M B Orr

Publications and source records attributed to M B Orr.

34 records · Page 2Linked to original sources
PubMed1986

A survey of excessively worn incisors and periodontal disease in sheep in Dunedin City, Silverpeaks, Bruce and Clutha Counties.

To determine the prevalence of excessively worn incisors (XSW) and periodontal disease (PD) in sheep in Dunedin City, Silverpeaks, Bruce and Clutha Counties, the incisors of 4049 mixed age ewes on 83 farms selected at random were examined between December 1983 and February 1984. Of these ewes, 14.9% had XSW (11.7% moderate, 3.2% severe), 13.7% had PD (10.5% moderate, 3.2% severe) and 71.4% had sound mouths. An additional 43 ewes had miscellaneous incisor faults, and these were excluded from the survey. Seventeen (>20.5%) and 25 (>30.1%) farms had 20% ewes with XSW and PD respectively. On two farms only did XSW and PD each occur at a prevalence of 15%. No association was found between the prevalence of XSW or PD and body condition score, breed or farm topography.

Journal Article↗
PubMed1985

The effect of gastro-intestinal parasitism on the temporary dentition of lambs.

The temporary dentitions of 18 to 39-week-old lambs with a very light or a very heavy parasite burden are compared. The heavily parasitised lambs developed longer temporary incisors which tended to protrude further forward in relation to the upper dental pad. They showed absolute hypocalcaemia and hypoalbuminaemia and relative hypophosphataemia and hypoproteinaemia and in the alveolar bone of the mandible there was a reduction in ash and matrix densities and matrix mineralisation. The incisor protrusion and lengthening may have been a consequence of the loss of supporting bone, but inappetance was likely to have been a factor contributing to the lengthening.

Journal Article↗
PubMed1985

A clinical study of periodontal disease in sheep.

Detailed examinations were made of the central permanent incisors and periodontia of 30 or 40 ewes on each of one control farm and three periodontal disease (P.D.) farms. The study confirmed that incisor crown lengthening, protrusion and loosening were significant features of P.D. Periodontitis (assessed by increased sulcus depth and bleeding after probing) about the lingual sulcus was a significant feature of P.D. Labial gingivitis and labial periodontitis were not significant features. A relatively long lower jaw did not appear to be a feature of P.D. 87.

Journal Article↗
PubMed1977

Histological and histochemical studies of fetal skin follicles in Border disease of sheep.

The structure of the epidermis and dermis, and the distribution of reticulin, glycogen, lipid and sulphydryl groups in the skin have been examined in control and Border disease affected sheep fetuses at 95 and 115 days' gestation. In Border disease, there was a temporary retardation of development of the epidermis and skin follicles at 95 days. There was no difference in the structure of the dermis between control and experimental fetuses at either age. No evidence was found to suggest that the keratogenous process was abnormal in Border disease, but the sulphydryl zone of the primary fibres of affected fetuses was situated nearer the skin surface than in control fetuses. This may have been a consequence of the larger size of primary follices in Border disease. Glycogen present in the undifferentiated epidermis of both groups at 95 days' gestation was absent from the stratified squamous epithelium of the 115 days's fetuses. Glycogen and lipid droplets were present in the outer root sheath of primary follicles of all fetuses examined, but their significance is unknown.

Animals↗
PubMedDate not supplied

Live sheep exports.

Explore the source record for details and available documents.

Letter↗