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A localised subcutaneous swelling developed on the nasal bridge of a cat receiving chemotherapy for alimentary tract lymphosarcoma. Cytological and histological examination of representative samples of the lesion demonstrated pyogranulomatous inflammation and abundant acid-fast bacilli. A Mycobacterium sp was cultured from tissue excised from the lesion. Extensive testing at three reference laboratories indicated the strain was a member of the Mycobacterium avium complex. The infection was treated successfully by cytoreductive surgery and a 6 weeks course of orally administered clofazimine. 相似文献
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SUMMARY Reproductive performance was compared between cows whose previous parturition was induced and non-induced cows with similar calving dates, in 49 winter-calving, pasture-fed, commercial dairy herds in south-western Victoria. Parturition was induced in winter when most cows were between 27 and 35 weeks of pregnancy. Reproductive performance was assessed during the next mating period after induction which was mainly in spring of the same year. Percentages of cows in induced and untreated groups that were not pregnant after the mating period (9.0% and 7.2%, respectively) did not differ significantly. Induction tended to increase the percentage of cows of unknown pregnancy status. Mean percentages for induced and untreated groups were 11.5% and 7.9%, respectively. Induced and untreated groups calved at similar intervals after the planned start of calving in the following year, and the percentages of groups that required induction in that year did not differ significantly. The direct effects of induced parturition on reproduction were therefore concluded to be minimal. In seasonal calving herds, improvements in reproductive performance could be expected among cows whose calving dates were altered substantially by induction, due to increased intervals from calving to mating start date . 相似文献
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Invertebrates on cut weed removed during weed-cutting operations along an English river, the River Frome, Dorset 总被引:2,自引:0,他引:2
Abstract. During weed-cutting operations on the River Frome, Dorset, England, cut weed (800t), together with associated macroinvertebrates, was removed at five boom sites down the river. The mean density of macroinvertebrates removed was 30 individuals per g dry weight of cut weed which was equivalent to 6mg dry weight per g of cut weed, ca. 4900 individuals per square metre of river bed, or 0.9g dry wt/m2 of river bed.
The cut weed removed was populated chiefly by larvae of Chironomidae and Simuliidae although the numbers and biomass of Ephemerella ignita Poda and Brachycentrus subnubilus Curtis were a significant part of the total macroinvertebrate population.
Macroinvertebrates removed on cut weed were estimated as ca. 20% by number and ca. 12% by biomass of the total population from published values. The river (50km) was difficult to sample immediately prior to weed cutting because of rapid changes in the density and position of invertebrate populations, the immense sampling effort required and the non-synchronous system of cutting. 相似文献
The cut weed removed was populated chiefly by larvae of Chironomidae and Simuliidae although the numbers and biomass of Ephemerella ignita Poda and Brachycentrus subnubilus Curtis were a significant part of the total macroinvertebrate population.
Macroinvertebrates removed on cut weed were estimated as ca. 20% by number and ca. 12% by biomass of the total population from published values. The river (50km) was difficult to sample immediately prior to weed cutting because of rapid changes in the density and position of invertebrate populations, the immense sampling effort required and the non-synchronous system of cutting. 相似文献
78.
SUMMARY The effects of induced parturition on clinical disease and mortality of cows were studied in 51 winter-calving, pasture-fed, dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Control groups were selected from herdmates that were not induced to calve. The incidence of retained placenta was much greater among induced cows of all ages. The proportion of cows affected by any clinical disease other than retained placenta, and the incidence of mortality were much greater after induction among cows aged over 6 years but not among cows aged 3 to 6 years. 相似文献
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Stuart J. DAWSON Tracey L. KREPLINS Malcolm S. KENNEDY Juanita RENWICK Mark A. COWAN Patricia A. FLEMING 《Integrative zoology》2023,18(2):299-315
Rangelands worldwide have been subject to broadscale modification, such as widespread predator control, introduction of permanent livestock water and altered vegetation to improve grazing. In Australia, these landscape changes have resulted in kangaroos (i.e. large macropods) populations increasing over the past 200 years. Kangaroos are a key contributor to total grazing pressure and in conjunction with livestock and feral herbivores have been linked to land degradation. We used 22 years of aerial survey data to investigate whether the density of 3 macropod species in the southern rangelands of Western Australia was associated with: (i) land use, including type of livestock, total livestock, density of feral goats, type of land tenure, and kangaroo commercial harvest effort; (ii) predator management, including permitted dingo control effort, estimated dingo abundance, and presence of the State Barrier Fence (a dingo exclusion fence); and (iii) environmental variables: ruggedness, rainfall, fractional cover, and total standing dry matter. Red kangaroos (Osphranter rufus) were most abundant in flat, open vegetation, on pastoral land, where area permitted for dingo control was high, and numbers were positively associated with antecedent rainfall with a 12-month delay. Western grey kangaroos (Macropus fuliginosus) were most abundant on flat, agricultural land, but less abundant in areas with high permitted dingo control. Euros (Osphranter robustus) were most abundant in rugged pastoral land with open vegetation, where permitted dingo control was high. While environmental variables are key drivers of landscape productivity and kangaroo populations, anthropogenic factors such as land use and permitted dingo control are strongly associated with kangaroo abundance. 相似文献