Search PubMed⌕ Search

Biomedical subjects

J G Ross

Publications and source records attributed to J G Ross.

At least 55 records · Page 3Linked to original sources
PubMed1979

Investigations of 'transfer factor' activity in the transfer of immunity to Trichostrongylus axei infections in sheep.

Three investigations are described in which non-dialysed and dialysed leucocyte lysates, 'transfer factor' prepared from the blood of sheep infected with Trichostrongylus axei successfully transferred immunity to challenge infection with that parasite in susceptible lambs. Similar leucocyte lysates from parasite-free lambs failed to transfer a similar resistance to challenge infection. 'Transfer factor' treatment produced a 30--72 per cent reduction in a total worm burden compared to susceptible control lambs. In the first two investigations the donor and recipient lambs were genetically dissimilar and in the third investigation were of different breeds. The resistance transfer was considered to operate independently of immune incompetence.

Animals↗
PubMed1979

Investigation of Haemonchus contortus infections in sheep. Comparison of irradiated larvae and transfer factor treatment.

A comparison is made between the resistance conferred to Haemonchus contortus challenge by irradiated larval treatment and transfer factor (TF) treatment in four-month-old lambs and seven-month-old lambs. As in previous investigations the irradiated larval treatment failed to confer resistance to the four-month-old lambs challenged with 10,000 third stage larvae while similar irradiated larval treatment in seven-month-old lambs reduced the worm burdens by 40 per cent compared to controls. The TF treatment produced a 34 per cent reduction in the challenge infection in the four-month-old lambs and a 45 per cent reduction in the seven-month-old lambs compared to the control lambs. It is concluded that TF activity operates independently of immune competence.

Animals↗
PubMed1978

Haematological and blood chemistry "comparison values" for clinical pathology in poultry.

Twelve blood chemistry values, six haematological values and bodyweight were estimated for six-week-old specific-pathogen-free brown leghorns. Observations were based on 208 birds sampled from 11 groups. Subsequently the same values were estimated for specific pathogen free brown leghorns and broiler hybrids of differing ages. These estimates have been designated "comparison values" and were intended for reference use in clinical pathology. Results were compared with 14 "comparison value" estimated obtained previously for six-week-old commercial broiler hybrids. Haematological values varied with age and type of bird. Differences were observed between bird types in serum protein, serum cholesterol, uric acid, calcium and potassium levels and in weight. The significance of these differences is discussed.

Age Factors↗
PubMed1977

Effect of transportation on blood metabolites in broilers.

1. Groups of 30 broilers from seven flocks were bled and weighed at the farm and a further sample of 10 broilers from each flock was transported from 8 to 16 km to the laboratory prior to bleeding and weighing. 2. One haematological and 11 biochemical analyses were made on each blood sample. 3. Although transportation did lead to significant differences in certain variables, the trends were consistent and sampling following transit is considered acceptable for clinical pathology studies.

Animals↗
PubMed1976

Experimental infections of sheep with Salmonella typhimurium.

Twenty-two-six-to nine-month-old lambs were infected orally with Salmonella typhimurium at levels varying from 2 x 10(13) to 1 x 10(9) and serially slaughtered to determine the pathogenesis of infection and to evaluate the efficacy of diagnostic procedures. Infection resulted in a severe fatal or potentially fatal clinical disease in lambs receiving 2 x 10(13) organisms. Observations were made on the clinical pathology, bacteriology and serology during the course of infection and extensive bacteriological examinations were undertaken at autopsy.

Animals↗
PubMed1976

Experimental infection of poultry with Salmonella infantis.

Six-month-old cockerels and point-of-lay pullets were infected orally with S infantis (1 X 10(10). The cockerels were slaughtered at intervals up to 42 days, and the pullets slaughtered 20 weeks, after infection. Infection produced no clinical disease and minimal changes were observed at autopsy. Serological responses were transient, frequently absent three to six weeks after infection, no response at all being recorded in some birds. Faecal excretion was observed most frequently during the early stages of infection. There was no evidence of egg transmission.

Animals↗
PubMed1975

Experimental infection of cockerels with Salmonella typhimurium.

Six-month-old SPF Brown Leghorn cockerels were experimentally infected per os with S typhimurium (1 times 1010) and slaughtered at intervals up to 42 days following infection. Observations were made on the clinical pathology, bacteriology and serology during the course of infection and extensive bacteriological examinations were undertaken after post mortem examination.

Administration, Oral↗