Smooth curve of evolutionary rate: a psychological and mathematical artifact   总被引：4，自引：0，他引：4  

Gingerich PD 《Science (New York, N.Y.)》1984,226(4677):994-996

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Rates of evolution: effects of time and temporal scaling     

Gingerich PD 《Science (New York, N.Y.)》1983,222(4620):159-161

Rates of morphological evolution documented in laboratory selection experiments, historical colonization events, and the fossil record are inversely related to the interval of time over which they are measured. This inverse relationship is an artifact of comparing a narrow range of morphological variation over a wide range of time intervals, and it is also a product of time averaging. Rates measured over different intervals of time must be scaled against interval length before they can be compared.  相似文献   

A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management          下载免费PDF全文

AJ Phipps  DS Beggs  AJ Murray  PD Mansell  MF Pyman 《Australian veterinary journal》2018,96(4):101-106

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.

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BVDV in Australian alpacas: natural infection and clinical profiles following co‐mingling with a persistently infected heifer          下载免费PDF全文

CA Evans  E Erregger  F Hemmatzadeh  PD Cockcroft 《Australian veterinary journal》2018,96(7):262-268

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Seroprevalence of antibodies to Pestivirus infections in South Australian sheep flocks          下载免费PDF全文

CA Evans  SR Lanyon  RM O’Handley  MP Reichel  PD Cockcroft 《Australian veterinary journal》2018,96(8):312-314

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Ostreid herpesvirus-1 microvariant surveillance in Pacific oysters (Magallana gigas,Thunberg, 1793) in Australia in 2011     

BJ Moloney  M Deveney  K Ellard  P Hick  PD Kirkland  NJG Moody  J Frances 《Australian veterinary journal》2023,101(9):345-355

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An outbreak of Akabane virus—induced abnormalities in calves after agistment in an endemic region     

S. JAGOE  PD KIRLAND†  PAW HARPER‡ 《Australian veterinary journal》1993,70(2):56-58

SUMMARY: During 1988, 2 farmers in the Bega district agisted pregnant cattle in the Hunter Valley of New South Wales. On return to the district to calve, 54% of calves from herd 1 and 30% of calves from herd 2 were affected with congenital arthrogryposls or hydranencephaly caused by Akabane virus infection. Field observations and laboratory findings from this outbreak are presented, illustrating the danger of moving immunologlcally naive animals into areas where Akabane virus is endemic.  相似文献   

Total intravenous feeding of calves.     

G F Hoffsis  D A Gingerich  D M Sherman  R R Bruner 《Journal of the American Veterinary Medical Association》1977,171(1):67-70

Total intravenous feeding was accomplished for 5 clinically normal calves and for 1 calf with atresia coli. During the trials, which lasted 8 to 14 days (mean of 12 days), calves were not permitted to ingest any food or water. Body weight and state of hydration remained essentially constant. Plasma protein content decreased, but there were only minor changes in other physiologic measures. Calves were clinically normal at the conclusion of the trials.  相似文献   

Diagnosis of myeloid leukosis induced by a recombinant avian leukosis virus in commercial white leghorn egg laying flocks   总被引：4，自引：0，他引：4  

Gingerich E  Porter RE  Lupiani B  Fadly AM 《Avian diseases》2002,46(3):745-748

Commercial white leghorn egg layer flocks being used to produce fertile eggs for human vaccine production exhibited dramatically low peaks in egg production, two to four times higher than normal weekly mortality, and high numbers of cull, nonlaying birds after the onset of sexual maturity. These lower production characteristics could not be associated with management-related problems. Gross lesions of cull and fresh dead birds necropsied showed approximately 60% lacked ovarian activity and had lesions of a bacterial bursitis or synovitis, whereas the other 40% had tumors of the viscera but not of the bursa of Fabricius. Histologic examination of tumor-containing tissues showed lesions typical of myelocytomatosis. The diagnosis of myeloid leukosis was confirmed by the isolation of a recombinant avian leukosis virus (ALV) containing the LTR of subgroup J and the envelope of subgroup B ALV. A positive polymerase chain reaction with primers specific for the 3' untranslated region LTR confirmed the presence of LTR of ALV-J. The source of infection with this recombinant ALV was not determined; however, it is likely that commingling of the day-old egg-type chicks with ALV-J-infected meat-type chicks in a common hatchery had contributed to this outbreak.  相似文献   

Otto Martin Radostits 1934 – 2006     

DC Blood  CC Gay  KW Hinchcliff  PD Constable 《Australian veterinary journal》2007,85(6):231-231

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