Cell counts of milk in relation to the pathology and bacteriology of bovine mastitis

Macadam, Ian (1956) Cell counts of milk in relation to the pathology and bacteriology of bovine mastitis. PhD thesis, University of Glasgow.

Abstract

The author prepared and stained 2,500 milk smears and counted the cells present. Centrifugalisation of milk failed to sediment all cells. Volumes lifted by various wire loops were studied. All cells, other than mammary epithelial, in milk appeared identical to blood cells. Most samples contained polymorphs, epithelial cells and lymphocytes. Variations in type and severity of lesions occurred in different parts of the same quarter. Pathology of 94 quarters was compared by a scoring system based on severity and extent of lesions. Total counts were generally directly related to extent of pathological changes. Polymorph proportions generally exceeded 70 per cent, in milk from acute inflamed quarters and were below 40 per cent, during involution without acute mastitis. Pathological changes in the ratio 8:4:2:1 were found associated respectively with C. pyogenes and Str. agalactiae: Str. uberis and coagulase-positive Staph, aureus; coagulase-negative Staph. aureus and sterile quarters: other bacteria. Ten most diseased quarters had larger circumferences at the canal rosette. Liability to mastitis appeared unaffected by pockets and ridges in teats. Transport of cows by lorry increased fivefold, on average, the cell counts of milk from 28 of 30 quarters and increased polymorph proportions in milk from acutely inflamed quarters.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: D F Cappell
• Keywords: Animal diseases
• Date of Award: 1956
• Depositing User: Enlighten Team
• Unique ID: glathesis:1956-73452
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jun 2019 08:56
• Last Modified: 14 Jun 2019 08:56
• URI: https://theses.gla.ac.uk/id/eprint/73452