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101.
102.
The rate of clearance of 125I-labelled polyvinyl pyrrolidone (PVP) from blood was measured in mares as an indicator of macrophage function. In three out of four cycling mares, PVP clearance was slower during oestrus than dioestrus. Similarly, administration of oestrogen to four ovariectomised mares tended to depress PVP clearance compared with clearance from the same mares before they received oestrogen. However, the effect of oestrogen was not statistically significant. Mares susceptible to persistent endometritis had rates of PVP clearance which were similar to those of genitally normal mares. 相似文献
103.
Clinical problems of preventive medicine. The prevention and control of infectious ovine abortion 总被引:1,自引:0,他引:1
W A Watson 《The British veterinary journal》1973,129(4):309-314
104.
At 6 months of age, an Old English Sheepdog with swollen and painful distal radial/ulnar metaphyses was found to have multiple cystic lesions in left and right radius and ulna. Cystic bone lesions were also detected radio-graphically in two clinically normal littermates and in the sire and dam of the litter. Radiographic changes of nutritional secondary hyperparathyroidism were found in the three affected pups and in two other individuals from the litter of eight.
The cystic lesions in one pup were drained surgically and the cyst wall curetted, while the other two pups were not treated. The lesions in all three pups gradually resolved and had almost completely disappeared by 10 months of age. 相似文献
The cystic lesions in one pup were drained surgically and the cyst wall curetted, while the other two pups were not treated. The lesions in all three pups gradually resolved and had almost completely disappeared by 10 months of age. 相似文献
105.
Absence of the transverse ligament of the atlas was diagnosed at necropsy in an 8-month-old Shih Tzu with radiographic signs of atlantoaxial subluxation. Symmetric ataxia, tetraparesis, and signs of pain in the vertebral canal suggested a lesion in the cervical portion of the spinal cord. Necropsy revealed absence of the transverse ligament of the atlas and malformation of dens and atlas. In addition, the alar ligaments were distinct and thick, and the atlanto-occipital and atlantoaxial joint capsules were markedly thicker than normal. Histologic examination revealed focal compressive myelopathy of the spinal cord at the level of the atlantoaxial joint. 相似文献
106.
107.
IMMUNITY TO EXPERIMENTAL STAPHYLOCOCCAL MASTITIS—COMPARISON OF LIVE AND KILLED VACCINES 总被引:1,自引:0,他引:1
SUMMARY Eleven pregnant Merino ewes were immunised with either a killed Staphylococcus aureus cell-toxoid vaccine (intramuscularly) or a living culture of the same organism (subcutaneously). A further 3 animals were used as non-immunised controls. There were no significant differences between the vaccinated groups for agglutinating antibody to staphylococci or for anti-α-haemolysin in either serum or whey. Three weeks after lambing the ewes were challenged by intramammary infusion of virulent staphylococci. All animals developed an acute mastitis with significant decreases in milk yields being recorded 48 hours post-challenge. Seven days after challenge the mean milk production of ewes given the live vaccine had recovered to within 5% of the pre-challenge mean yield. However, milk productions of controls and ewes given the killed vaccine had further decreased and were significantly lower than for animals vaccinated with live staphylococci. There were no significant differences between the two vaccinated groups for numbers of bacteria or leucocytes in milk samples collected after challenge. The ewes were killed 7 days postchallenge and mammary tissues were examined for immunoglobulin-containing cells. Large numbers of IgA-containing cells, and few IgM-containing cells were found, but there were no significant differences between the treatment groups for these parameters. 相似文献
108.
109.
110.
P F Watson 《The Veterinary record》1975,97(1):12-15
Acrosomal structures of ram spermatozoa were prominently stained when air dried smears of diluted semen were fixed for 15 minutes in buffered formal saline and stained for 90 minutes in a 6 per cent (v/v) buffered solution of Giemsa stain. Progressive disruption of the acrosomes was demonstrated during chilling and deep-freezing of the spermatozoa, and the degree of damage was systematically scored. A rapid and repeatable estimate of the state of the acrosomes in a sample could be made from the mean score of 20 spermatozoa examined per slide. 相似文献