Physical characteristics of the bovine teat canal and their influence on susceptibility to streptococcal infection
| Autor: | Hillerton Je, Lacy-Hulbert Sj |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Veterinary medicine
medicine.disease_cause Intramammary infection Microbiology Streptococcus agalactiae Mammary Glands Animal Streptococcal Infections medicine Animals Lactation Mastitis Bovine biology Inoculation Incidence (epidemiology) General Medicine medicine.disease Streptococcaceae biology.organism_classification Mastitis Dairying Kinetics Keratins Regression Analysis Animal Science and Zoology Teat canal Cattle Female Disease Susceptibility Somatic cell count Food Science |
| Zdroj: | The Journal of dairy research. 62(3) |
| ISSN: | 0022-0299 |
| Popis: | SummaryPhysical characteristics of the bovine teat canal were examined for their influence on susceptibility to intramammary infection. All quarters of 18 cows were inoculated with 2 × 105 cfu Streptococcus agalactiae (Trial 1) and 20 cows with 105 cfu Str. Uberis (Trial 2) 3–4 mm into the teat canal every 3 d for 12 d. Incidence of quarter infection was similar for both pathogens, 30/72 (42%) in Trial 1 and 32/80 (40%) in Trial 2. Logistic regression analysis showed that probability of infection by Str. Agalactiae increased significantly with an increase in quarter peak flow rate (P < 0·05) whereas probability of infection increased for Str. Uberis with a decrease in teat canal length (P < 0·05). A significantly higher (P < 0·001) incidence of infection by Str. Uberis was observed in quarters that contained a low wet weight (< 1·8 mg) of removable keratin compared with those that contained > 1·8 mg keratin, but there was no correlation between weight of keratin and length of the teat canal. Infections by Str. Uberis took significantly less (P < 0·05) time to show a rise in somatic cell count above 7·5 × 105 cells/ml than Str. agalactiae. The results provide evidence that these pathogens use different mechanisms to pass through the teat canal. |
| Databáze: | OpenAIRE |
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