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991.
L.H. Campbell 《Biological conservation》1984,28(2):173-180
Changes in the numbers and distribution of seaducks wintering in the Firth of Forth off Edinburgh following the introduction of sewage treatment are described. Numbers of scaup and goldeneye were considerably reduced and feeding flocks were only recorded at outfalls where sewage continued to be discharged in large quantities.Although food items borne in the sewage were important in determining local distribution patterns, it was unclear whether these or abundant invertebrates were the most important factor attracting seaducks to this area.As a result of an environmentally desirable improvement scheme the United Kingdom has lost an internationally important concentration of wildfowl. 相似文献
992.
Sheep given a primary infection of Fasciola hepatica were challenged 18 weeks later with Taenia hydatigena or F hepatica, or both parasites together, or were not challenged. At the same time, control sheep were infected with T hydatigena and/or F hepatica separately or concurrently. All sheep were killed seven weeks after challenge and the number of cysts and flukes counted. Challenge infection with T hydatigena did not affect the numbers of flukes recovered from either primary or challenge F hepatica infections. On the other hand, the numbers of cysticerci were reduced in sheep previously infected with F hepatica but not in those given T hydatigena and F hepatica concurrently. 相似文献
993.
The role of infectious agents on dairy farms on the Atherton Tableland in tropical north Queensland was studied as part of a comprehensive investigation into the causes of bovine abortion. The prevalence of antibody in serums collected from 7 herds whose annual abortion rates ranged from 3% to 21% were as follows: Leptospira hardjo 49.9% (426/853), L. pomona 0.4% (3/851), bovine virus diarrhoea (BVD) 33.7% (35/104). Infectious bovine rhinotracheitis virus (IBR) 11.5% (12/105), Akabane virus 92.2% (95/103), Aino virus 62.1% (64/103), Chlamydia psittaci 3.1% (37/1004), Brucella abortus 0% (0/851), and Toxoplasma gondii 0% (0/105). Testing of serums against a wide range of leptospiral serotypes indicated that reactions occurring in the Hebdomadis and Sejroe serogroups were probably cross reactions with L. hardjo. Infection with L. hardjo and Akabane virus occurred prior to first mating and contact with Aino virus occurred during first pregnancy. Infection with BVD and IBR viruses was sporadic. The pathology and microbiology of 32 aborted foetuses from 24 Tableland herds (10 from the group of 19 farms under more intense study) were performed. Lesions associated with a Sarcocystis-like agent were present in 6, leptospires in 1, suspected toxic hepatosis in 2 and purulent bronchopneumonia (Staphylococcus aureus) in 1 foetus. No diagnoses were made in the remaining 22 foetuses (69%). Evidence for a common infectious cause of abortion in the population was inconclusive. 相似文献
994.
W E Campbell 《Modern veterinary practice》1975,56(7):492-494
995.
T W Campbell 《Veterinary Clinics of North America: Small Animal Practice》1988,18(2):349-364
Cytology and hematology can provide valuable information during the evaluation of fish patients. Although more commonly practiced with larger species of fish, hematologic evaluation aids in the identification of diseases that have an effect on the cells in peripheral blood in the same manner as in mammalian and avian patients. Cytology provides clinical diagnostic support in the evaluation of the health status of even the smallest fish. 相似文献
996.
SUMMARY: In 6 years snake bite was diagnosed in 41 cats, with an average age of 20 months. The commonest presenting signs were dilated pupils, absence of the pupillary light reflex, depression and generalised muscle weakness. Other frequent findings were vomiting, dyspnoea, hindlimb ataxia and complete flaccid paralysis. Thirdy-seven cases (90%) occurred in the 6 warmer months of the year. Tiger snakes were positively identified in 7 cases. A recovery rate of 89% was obtained in cases receiving 3000 units Tiger snake antivenene, fluid therapy and nursing. Cases presenting with a complete flaccid paralysis and sub-normal temperatures were poor prognostic risks. 相似文献
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1000.
L H Campbell H K Okuda D E Lipton C Reed 《American journal of veterinary research》1975,36(5):669-671
Dogs affected with chronic superficial keratitis (CSK) and clinically normal dogs were tested for cellular hypersensitivity, using the leukocyte migration-inhibition (LMI) technique to 3 ocular antigens (Staphylococcus aureus and corneal and iridal proteins). Affected dogs had statistically significant increases in hypersensitivity cellular responses against corneal and iridal antigens. Affected dogs did not differ from clinically normal dogs in their cell response to S aureus. 相似文献