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Estimates of forage production and consumption were made, using dry-weight differences between samples from protected and grazed areas. Two sizes of cage for protecting areas from grazing were compared in four forages: brome grass (Bromus inermis Leyss.)/Iucerne (Medicago sativa L.); crested wbeatgrass (Agropyron crista-tum L.)/lucerne; intermediate wbeatgrass (A. intermedium (Host.) Beauv.)/Iucerne; and Russian wild-rye (Elymus junceus Fisch.). Production, over a three-year period, ranged from 1985 to 6286 kg/ha when estimated from 0.84 m2 cages. Consumption ranged from 1584 to 5878 kg/ha. Yield estimates wben using 2.51 m2 cages averaged 8% less than estimates from 0.84 m2 cages. The number of caged sites needed in each plot to estimate a 95% confidence interval for annual production were 14 for four replicates, and over 30 for fewer replicates. Requirements for consumption estimates were similar. To estimate production within a 90% confidence interval 19, 10 and 4 caged sites were required from two, three, and four replicates, respectively. Consumption estimates within tbis confidence interval required 22, 10, and 5 samples from two, tbree, and four replicates, respectively. Caging requirements were tbe same for all combinations of plot size and forage species. Large cages increased precision sligbtly wben used on Russian wild-rye, probably because the forage was in rows 0.91 m apart.  相似文献   
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Objective To determine the extent of the snake bite problem in domestic animals, its regional significance and the effects of antivenom treatment.
Design A questionnaire was designed seeking information on the number and type of domestic animals referred, whether treated or untreated, type of snakes and management of the bite.
Procedure The survey form was sent to 10% of veterinary surgeons, selected at random throughout Australia.
Results The response of 106 veterinary surgeons revealed that snake bite in domestic animals is frequent, with an estimated 6200 cases reported annually. Bites were more prominent in rural (78%) than urban areas (22%) with brown, tiger and black snakes accounting for 76%, 13% and 6% of cases, respectively. Cats and dogs were the most frequently reported victims. Ninety-one percent of cats and 75% of dogs survived following the administration of antivenom whereas 66% of cats and 31% of dogs survived without antivenom. Overall, in 33% of cases antivenom was not used, and venom detection kits were used in only 1% of cases. A number of drugs were used in various combinations with or without antivenom and intravenous fluids in the treatment of animals with snake bite, but their role in reducing the severity of envenomations was not assessed.
Clinical implications Antivenom significantly improves the chances of survival of domestic animals bitten by snakes.  相似文献   
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Foot and mouth disease (FMD) is a highly transmissible viral infection of cloven hooved animals associated with severe economic losses when introduced into FMD-free countries. Information on the impact of the disease in FMDV-endemic countries is poorly characterised yet essential for the prioritisation of scarce resources for disease control programmes. A FMD (virus serotype SAT2) outbreak on a large-scale dairy farm in Nakuru County, Kenya provided an opportunity to evaluate the impact of FMD on clinical mastitis and culling rate. A cohort approach followed animals over a 12-month period after the commencement of the outbreak. For culling, all animals were included; for mastitis, those over 18 months of age. FMD was recorded in 400/644 cattle over a 29-day period. During the follow-up period 76 animals were culled or died whilst in the over 18 month old cohort 63 developed clinical mastitis. Hazard ratios (HR) were generated using Cox regression accounting for non-proportional hazards by inclusion of time-varying effects. Univariable analysis showed FMD cases were culled sooner but there was no effect on clinical mastitis. After adjusting for possible confounders and inclusion of time-varying effects there was weak evidence to support an effect of FMD on culling (HR = 1.7, 95% confidence intervals [CI] 0.88-3.1, P = 0.12). For mastitis, there was stronger evidence of an increased rate in the first month after the onset of the outbreak (HR = 2.9, 95%CI 0.97-8.9, P = 0.057).

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0173-4) contains supplementary material, which is available to authorized users.  相似文献   
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Objective To evaluate ketoprofen for the therapy of ephemeral fever.
Design A blind controlled clinical trial.
Animals Sixteen cattle (one immature Holstein bull, eight Holstein and seven Jersey heifers).
Procedure Ephemeral fever was induced by the intravenous injection of blood leucocyte layer from a clinical case. Ketoprofen solution or a coded placebo was injected intramuscularly at the rate of 3 mg/kg daily for three days.
Results Ketoprofen reversed locomotor dysfunctions significantly compared with controls, but did not have any effect on rectal temperatures, leucocyte counts, plasma fibrinogen concentrations, ionised Ca-concentrations or the presence of dyspnoea.
Conclusion Ketoprofen is a safe and effective drug for the treatment of locomotor symptoms of milk fever, but has no effect on the duration of clinical respiratory abnormalities.  相似文献   
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The time scales over which inner solar system objects accreted and differentiated are unclear because the isotopic systems of many meteorites are disturbed. 182Hf decays to 182W with a half-life of 9 million years and is a particularly useful chronometer because both elements are highly refractory and immobile. Tungsten isotopic data for IIA, IIIA, IVA, and anomalous iron meteorites and H, L, and LL chondrites indicate that their parent bodies accreted rapidly and segregated metal within just a few million years.  相似文献   
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1. Individually caged laying hens had a loop of thread inserted into the shell gland. This resulted in the laying of soft shelled eggs. 2. A balance study was performed for a one week period before and after the operation. After the operation birds with threads consumed less calcium than before. Their requirements for calcium for eggshells decreased, resulting in increases in both calcium excreted and calcium retained. 3. Net calcium extraction in the digestive tract was measured in groups of birds with threads and intact controls, when shelling or not, by examining ratios of Ca to TiO2 in different gut segments. Observations were made during the period following premature oviposition in birds with threads, but within the normal shelling period of control birds. The period of study was at least two weeks after the operation. 4. Birds with threads absorbed less calcium than control birds up to the upper jejunum. 5. Control birds secreted calcium between the upper jejunum and colon, but birds with threads showed little change in absorption in this part of the digestive tract. 6. The increase in calcium absorption in intact birds was a response to the stimulus of shelling an egg or replacing calcium in medullary bone during a pause day, rather than of ovulation.  相似文献   
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