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Biomedical subjects

A Greig

Publications and source records attributed to A Greig.

60 records · Page 4Linked to original sources
PubMed1971

The growth and persistence of foot-and-mouth disease virus in the bovine mammary gland.

In animals exposed to foot-and-mouth disease virus by indirect contact, virus was recovered from the blood, milk, pharynx, vagina and rectum for variable periods of time before clinical disease was apparent. Virus instilled into the mammary gland multiplied rapidly and virus concentrations greater than 10(7) p.f.u./ml. were recorded within 8-32 hr., depending on the virus strain and dose inoculated. Virus multiplication was accompanied by clinical signs of mastitis but the classical signs of foot-and-mouth disease did not appear for 52-117 hr. Dissemination of virus from the mammary gland occurred within 4-24 hr. and in some animals samples taken from the pharynx, mouth, nose and vagina contained virus for periods up to 97 hr. before the appearance of vesicular lesions. Virus production in the udder declined with the appearance of virus neutralizing activity in the blood and the milk but persisted in some animals for periods of 3-7 weeks. The ability of foot-and-mouth disease virus to persist in mammary tissue was confirmed by the demonstration of virus multiplication in the udders of immune animals.

Animals↗
PubMed1970

The excretion of two virulent strains of African swine fever virus by domestic pigs.

Daily observations were made on the excretion of African swine fever (ASF) virus by pigs infected intranasally or by contact. Two strains of virus having mean death times of approximately 3 and 6 days were used, the latter being recently isolated from a warthog.First excretion usually occurred by the nasopharyngeal route, as early as 1 or 2 days before the onset of fever in many cases. The titres of pharyngeal and nasal swabs rose rapidly to reach mean levels of about 10(4)-10(5) HAD 50 at 48-72 hr. following the onset of pyrexia. Virus in the secretions of the conjunctiva or lower urogenital tract appeared later and did not attain such high levels. Faecal and urinary excretion was of relatively little significance, except in slower infections caused by the recent warthog virus.These results are discussed in relation to the known failure of infected pigs to transmit the disease to stallmates during the first 12-24 hr. of pyrexia and also in relation to recent work on the pathogenesis of ASF in domestic swine.

African Swine Fever↗
PubMedDate not supplied

Role of oxytetracycline dihydrate in the treatment of mycoplasma-associated ovine keratoconjunctivitis in lambs.

Thirty-six lambs were placed in two groups of 10 each, one group of 11 and one group of five. The first three groups were challenged with a field strain of Mycoplasma conjunctivae and the group of five lambs with an inactivated culture. One group of lambs was treated with oxytetracycline dihydrate as conjunctivitis developed at 1 day post-inoculation (dpi) and the other group was treated when the conjunctivitis was at its most severe (3 dpi). A rapid response to treatment was observed with a complete recovery obtained after 2 and 4 days, respectively. However, the treatment did not eliminate the M. conjunctivae infection. Conjunctivitis did not develop in the five lambs challenged with the inactivated culture.

Animals↗