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Biomedical subjects

R D Cameron

Publications and source records attributed to R D Cameron.

34 records · Page 2Linked to original sources
PubMed1980

The prevalence of Brodetella bronchiseptica and turbinate (conchal) atrophy in English pig herds in 1978-79.

Examination of pigs (eight to 10 per farm) slaughtered between December 1978 and March 1979 at abattoirs in southern England indicated that infection with Bordetella bronchiseptica was widespread. The organism was recovered from the nasal cavity of 424 out of 844 (50 per cent) of such pigs and these were distributed among 79 out of 86 (91 per cent) of the herds submitting animals. The sensitivity to sulphonamide or potentiated sulphonamide of 255 of these strains was determined: in 20 out of 70 (25 per cent) herds there was partial or complete resistance to the former drug and, in 16 out of 79 (20 per cent), to the latter also. Despite this general level of infection and bacterial resistance the prevalence and severity of turbinate atrophy was less than in a survey undertaken by others in 1974. Thus about 74 per cent of pigs had no or minor atrophy only and about 10 per cent severe lesions. Some 10 per cent of the farms sent groups in which the majority of the pigs had severe atrophy.

Animals↗
PubMed1980

Effect of feeding regimen on gastric ulceration of the pars oesophagea of intensively raised pigs.

Three groups of pigs (total 23 pigs) were fed ad libitum from weaning until market weight and these were compared with three groups of pigs (total 26 pigs) fed ad libitum until 12 weeks of age, and then fed on a restricted regimen (twice per day) until marketed. There was a significant difference in degree of ulceration between the two feeding regimens; those pigs fed ad libitum had the most severe gastric ulcers. The pigs fed ad libitum, had significantly less agonistic interactions per minute than did the restricted fed pigs. Growth rates of the pigs from weaning to market weight did not differ significantly in the two regimens, although the average pig on ad libitum feeding consumed 182.9 kg, and the restricted fed pigs ate 148.2 kg per pig.

Agonistic Behavior↗
PubMed1980

The effect of elevated ambient temperature on spermatogenesis in the boar.

Boars were heated for 6 h/day in a climate chamber (mean maximum temperatures, 33.4 +/- 3.1--37.7 +/- 2.0 degrees C, and relative humidities 40--80%) for 4, 5 and 7 days respectively (4 boars/group). Significant increases in the proportion of morphologically abnormal spermatozoa were seen in all groups for the end of Week 2 and up to Week 5 after treatment. Boars exposed for 7 days were, in general, more severely affected. Ejaculate volumes, gel volumes, sperm concentration and daily sperm outputs were not affected significantly in any of the groups, although changes were seen in individual animals. In some boars heat stress early in the treatment period produced an acute rise in body temperature which appeared to have a greater effect on semen quality than did the duration of exposure.

Animals↗
PubMed1979

An outbreak of porcine pleuropneumonia due to Haemophilus parahaemolyticus.

An outbreak of porcine pleuropneumonia in an intensive piggery in south-eastern Queensland is described. Haemophilus parahaemolyticus was isolated from weaner piglets at post-mortem examination. The disease began in weaners and later occurred in suckling piglets 3 weeks of age. It was associated with poor ventilation, hygiene and overcrowding. Treatment and control measures included intramuscular lincomycin hydrochloride (10 mg/Kg body weight), creep feed medication with oxytetracycline (500 g/tonne) and disinfection and improvement of housing. These appeared to be successful.

Animals↗
PubMed1977

Pregnancy diagnosis in the sow by rectal examination.

A detailed description is given of the reproductive tract of the sow as felt by rectal examination. Rectal examination was found to have a 94.3% accuracy in determining pregnancy when carried out between 30 and 60 days gestation. Rectal examination was also found to be a suitable method of detecting the onset of oestrus in the sow. The advantages of using rectal examination as a routine procedure to determine pregnancy in commercial sow herds are presented.

Animals↗
PubMed1977

Semen collection and evaluation in the ram. The effect of method of stimulation on response to electroejaculation.

Nine different methods of electrical stimulation with a bi-polar rectal probe, were used on 5 rams. The quantity and quality of semen collected, the time taken to produce ejaculation and the maximum voltage required were compared. Semen of good quality was collected by applying a stimulus every 7 seconds for a period of 3 seconds commencing at 1 volt and increasing by 1 volt at a time. A mean maximum voltage of 5.1 volts produced ejaculation. Electrical stimulation, using a voltage rise of 2 volts applied at 5 sec intervals frequently produced smaller volumes of semen, a greater number of collection failures, and severe physical stress to the rams.

Animals↗
PubMed1977

Semen collection and evaluation in the ram. The preparation of spermatozoa for morphological examination.

Tail and mid-piece morphology of ram spermatozoa were compared using wet preparations of semen diluted in buffered formal saline at temperatures of 10 degrees C and 65 degrees C. The temperature of the diluent did not affect the occurrence of abnormalities. Tail and mid-piece morphology were also examined in semen smears stained by a modified Williams' stain using glass slides at temperatures of 10 degrees C, 38 degrees C and 65 degrees C. The occurrence of the abnormalities was not affected by the slide temperature. The occurrence of tail and mid-piece abnormalities was compared using the 2 methods of preparation. Only the occurrence of distal cytoplasmic droplets was affected by the method of preparation. In the stained smear preparations, most of the distal cytoplasmic droplets were lost. However, only a few of the proximal droplets were lost when this method was used.

Air↗
PubMed1976

Characteristics of semen changes during Brucella ovis infection in rams.

The effect of brucellosis on semen quality in rams was studied by means of artificially infecting five rams with a strain of Brucella ovis isolated in Kenya. Infection resulted in reduced semen quality including reduced total sperm output, poor motility and a high percentage of morphological abnormalities. Variation in semen quality both between and within rams appeared to be related to progress of the disease in the epididymis as well as to the distribution and severity of lesions in the reproductive tract.

Animals↗
PubMedDate not supplied

Sebaceous variant of mucoepidermoid carcinoma of the salivary gland. A case report with cytohistologic correlation.

The findings on fine needle aspiration biopsy cytology of a case of sebaceous variant of mucoepidermoid carcinoma of the parotid gland are described. The aspirates consisted predominantly of uniform intermediate-type epithelial cells, which led to erroneous diagnosis of a benign neoplasm. The cytologic features of the intermediate, clear, mucinous and sebaceous cells were correlated with the different histologic patterns seen within the neoplasm. Problems encountered with the diagnosis are discussed.

Adenocarcinoma↗