The surgical correction of a deviated anterior maxilla in a horse     

GMW McKELLAR  AP COLLINS 《Australian veterinary journal》1993,70(3):112-114

SUMMARY The surgical correction of facial deformities of the horse have rarely been undertaken. The surgical and medical management of submucous clefting of the anterior maxilla in a young colt is described.  相似文献   

Fisher's Letters     

Dempster AP 《Science (New York, N.Y.)》1991,252(5002):143-144

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The analysis of biological populations: by Mark Williamson. Edward Arnold Ltd,London: xi + 180 pp., £4.00 (£2.00 paperback), 1972.     

J.P. Dempster 《Biological conservation》1974,6(2):155-156

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The dynamics of arthropod predator-prey systems: By Michael P. Hassell. Monographs in Population Biology 13. Princeton University Prses,New Jersey, 1978. vii + 237 pp. 22·5 × 14·5 cm. Price: cloth £10·70; paper £4·65     

J.P. Dempster 《Biological conservation》1979,16(4):321

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Suspected salmonellosis in seven broodmares after transportation     

SA McCLINTOCK  AP BEGG 《Australian veterinary journal》1990,67(7):265-267

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POSITIVE RAY ANALYSIS OF LITHIUM     

Dempster AJ 《Science (New York, N.Y.)》1921,53(1372):363-364

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Anthelmintic resistance and management of nematode parasites on beef cattle-rearing farms in the North Island of New Zealand     

R Jackson  AP Rhodes  WE Pomroy  DM Leathwick  DM West  TS Waghorn 《New Zealand veterinary journal》2013,61(6):289-296

AIM: To provide information on current farmers’ opinions and farming practices thought to be related to anthelmintic resistance, and to test for associations between the presence of anthelmintic resistance and management practices on beef cattle- rearing farms in the North Island of New Zealand.

METHODS: A study using an interview-based questionnaire about management of internal parasites was conducted on 62 beef cattle-rearing farms in the North Island of New Zealand, using case-control analyses to test for associations between management practices and the presence or absence of resistance to ivermectin or albendazole. Resistance was inferred from faecal nematode egg count (FEC) reduction (FECR) tests (FECRTs) when there was <90% reduction in FEC 7-10 days after treatment of calves <12 months of age.

RESULTS: Of the 59 farmers who completed the questionnaire, most (n=40) ranked parasites highly, and at about the same level as quality and quantity of feed, as important production-limiting factors for their enterprises. In contrast, anthelmintic resistance was not perceived to be a problem on 13 farms, and its importance was rated low on 24, moderate on 15, and high on only six farms. Despite all farms having planned parasite control programmes, there was heavy reliance on clinical signs of parasitism to determine frequency of treatments. About one in three farmers with beef breeder cows routinely treated their calves at marking, one in five treated mixed-age cows, and almost half treated rising 2-year-old cows before calving. One in four farmers used anthelmintics on calves on 8–12 occasions in their first year of life. Co-grazing with other species was rare, but follow-on grazing within 3 months after older cattle or sheep was common. On most farms, grazing cattle was restricted to part of the farm, a finding with implications for parasite control and persistence of larvae in refugia. Macrocyclic lactone (ML) anthelmintics or their combinations with other action families were currently, and for the past 5 years, used more frequently than benzimidazoles and levamisole, and benzimidazole-levami- sole combinations. The prevalence of resistance to ivermectin was high (82%) and no plausible model of associations could be constructed from the data. The prevalence of resistance to albendazole was 60%, and the risk of resistance increased as the number of rising 1-year-old cattle present mid-winter increased, and decreased as the number of breeding cows >2 years old present mid-winter increased.

CONCLUSION: It is clear that in practice anthelmintic resistance is a secondary consideration to obtaining productivity advantages from the use of anthelmintics in beef cattle. Farmers’ opinions were divided on many issues and the overall impres- sion was of confused and diverse thinking regarding the principles of the use of anthelmintics. The overall outlook regarding anthelmintic resistance in cattle is bleak unless the need for integrated and long-term research activities is acted upon soon.  相似文献   

Endocrine Regulation of the Establishment of Spermatogenesis in Pigs     

KC Caires  JA Schmidt  AP Oliver  J de Avila  DJ McLean 《Reproduction in domestic animals》2008,43(S2):280-287

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Localization of metastable atom beams with optical standing waves: nanolithography at the heisenberg limit     

KS Johnson  JH Thywissen  NH Dekker  KK Berggren  AP Chu  R Younkin  M Prentiss 《Science (New York, N.Y.)》1998,280(5369):1583-1586

The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography.  相似文献   

Duration of immunity, efficacy and safety in sheep of a recombinant Taenia ovis vaccine formulated with saponin or selected adjuvants.     

G. B. L. Harrison  T. R. Shakes  C. M. Robinson  S. B. Lawrence  D. D. Heath  R. P. Dempster  M. W. Lightowlers  M. D. Rickard 《Veterinary immunology and immunopathology》1999,70(3-4):161-172

The efficacy and safety of a recombinant Taenia ovis protein was tested in sheep using 13 different adjuvant formulations, including oil adjuvants, aluminium salts, saponin, Iscoms and DEAE-dextran. The oil adjuvants, saponin and DEAE-dextran gave the highest antibody responses and greatest degree of protection against challenge infection with T. ovis eggs. Duration of immunity studies with a saponin based vaccine showed that highly significant protection (>90% reduction of cyst numbers) was achieved when sheep were challenge infected one month after immunisation. Significant protection (79%) was still present when sheep were challenged 6 months after immunisation. The optimum dose for this batch of saponin was 10 mg, which stimulated a peak antibody titre of 38,400, 4 weeks after immunisation and did not cause injection site reactions. Dialysed saponin was shown to retain its adjuvant properties and allowed an increase in dose to 30 mg without site reaction, resulting in a peak antibody titre of 51,200.  相似文献