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Lymphocytes from 5 clinically normal lambs and 5 lambs affected with ovine hereditary chondrodysplasia (spider syndrome) were cultured, G-banded, and karyotyped. Fifty metaphase karyotypes and one heterogram were evaluated for chromosome number and morphologic features. All lambs had normal diploid (2n) chromosome numbers of 54,XX or 54,XY, and there were no apparent differences in the morphologic features of the chromosomes.

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chromosome banding dysplasia chromosomes genetics genetic disorders chromosome banding chromosome morphology sheep diseases female g bands metaphase karyotyping ...

National Agricultural Library - United States of America

Morphologic changes in the bovine mammary gland during involution and lactogenesis

1988

Sordillo, L.M. | Nickerson, S.C.

Morphologic changes developing during bovine mammary involution were examined. Quarter biopsy specimens were obtained weekly from 5 cows beginning the day milking was discontinued through parturition. Light and electron microscopic examination of mammary tissue indicated a gradual reduction in synthetic and secretory activity of alveolar epithelium as involution progressed. Light microscopic morphologic analysis revealed increases in stroma and nonactive secretory epithelium, with concomitant decreases in epithelium, lumen, and fully active secretory epithelium during the first 2 weeks of involution. Electron microscopic analysis of alveolar epithelium revealed decreased number of organelles associated with milk synthesis and secretion during this time. These changes reversed gradually beginning 2 weeks before parturition, and by the time of calving, cell structure was typical of lactating glands. Tissue from infected quarters had less synthetic and secretory ability as indicated by significantly higher percentages of stroma and nonactive cells, but lower percentages of lumen and moderately active cells, compared with uninfected quarters. Infected quarters also had more leukocytes infiltrating the epithelium, lumen, and stroma, compared with uninfected quarters. Microscopic examination of macrophages and neutrophils suggested these cells removed milk components and cellular debris during involution. Large numbers of plasma cells, with distended cisternae of rough endoplasmic reticulum, suggested local antibody production during the periparturient period.

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cattle microscopy labor milk secretion lactation cows female mammary tissue electron anatomy and morphology obstetric time factors ...

National Agricultural Library - United States of America

A new cestode, Raillietina (Raillietina) oligocapsulata n. sp., and R. (R.) demerariensis (Daniels, 1895) from Venezuelan mammals

1988

Sato, H. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Okamoto, M. | Ohbayashi, M. | Basanez, M.G.

raillietina lagomorfos lagomorphe especies nuevas hosts new species venezuela/ anatomie animale venezuela/ anatomia animal huespedes venezuela/ animal morphology hote espece nouvelle ...