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OBJECTIVE: To estimate and predict changes in the cat population of Australian households from 1979 to 2005. METHOD: Telephone surveys were used to estimate Australia's total household cat population for each year from 1979 to 1999. A simple mathematical model based on population characteristics in 1995 was used to predict future population changes to 2005. Estimates and predictions for 1996 to 1999 were compared to validate the model. RESULTS: Australia's household cat population increased steadily from 2.23 million in 1979 to peak at 3.24 million in 1988. Since then it has steadily declined to 2.60 million in 1999. The population size predicted from the mathematical model was similar to that from surveys for the years 1996 to 1999. It is predicted that the population will continue to decline to approximately 2.19 million in 2005. The proportion of Australian households owning cats fell from 31.1% in 1994 to 25.8% in 1999, while the average number of cats per cat-owning household remained relatively constant at 1.47. CONCLUSIONS: Australia's household cat population is decreasing, falling by 19% between 1988, when it reached its peak, and 1999. This contrasts with the US where the population increased by 13.9% over the same period. The decline in Australia appears to be due to a decrease in the total number of cat-owning households rather than the number of cats per cat-owning household. It is likely that this trend will continue unless there is a change in household pet ownership preferences in the meantime.  相似文献   
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内部的挑战和机遇 生产和均一性 挖掘遗传的潜力,也就是繁殖性能或生长的潜力,对于动物养殖业来说是一个连续的挑战。营养通常不是限制的因素。然而,营养学家和养殖者承担这一挑战。为了最大程度地发挥动物的生产性能的潜力,高精确度的分析技术,包括DNA排列顺序,使我们能够充分了解和分析胃肠  相似文献   
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Sparkes A  Wray J  Leece E  de Risio L  Murphy S  Furneaux R  Sansom J  Coatesworth J 《The Veterinary record》2007,161(24):826; discussion 826-826; discussion 827
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Several studies have evaluated the spatial distribution of cool- and warm-season grasses across different topographic positions in the Nebraska Sandhills, but limited research has explored topographic differences in total plant production or production of plant functional groups in relation to variable amounts of precipitation. This study evaluated how spring and growing season precipitation influenced plant production at four topographic positions common in the eastern Nebraska Sandhills. Plant production data were collected from annually moved grazing exclosures in mid-June (peak cool-season grass production) and mid-August (peak warm-season grass production) during a 17-yr period from 2001 to 2017. Total plant production and precipitation use efficiency were 35 ? 58% greater on interdune positions, and precipitation marginal response for total plant production was more sensitive to increases in spring and growing season precipitation on interdune compared with dune positions in both mid-June and mid-August. The greater precipitation marginal response of total plant production on interdune positions was driven primarily by greater increases in cool-season grass production with increasing spring or growing season precipitation. Warm-season grass precipitation marginal response was not different among the topographic positions, but production was 23 ? 70% greater on interdune compared with dune topographic positions in mid-August. When differences in the amount of each topographic position at the study location were accounted for, growing season precipitation explained 49% of the variation for total plant production in mid-August, but spring precipitation only explained 23% of the variation for total plant production in mid-June. Because of the differential response of plant production at dune and interdune positions, incorporating the relative amount of each topographic position into estimates of plant production at the pasture or ranch scale will provide better information for adjusting stocking rates to more accurately match animal demand with forage availability.  相似文献   
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在过去的20年内美国的猪产业发生了翻天覆地的变化。多址生产系统对畜群的健康和控制断奶仔猪链产生了极大的作用。然而一个成功的断奶仔猪营养方案其基本原则对于任何日龄断奶的仔猪来讲都是相似的。可以归纳成三点:①在断奶时,仔猪尽可能的体重大;②尽可能快的将日粮从复合日粮转化为简单日粮;③重点关注保育仔猪管理。此外,在美国过去的10年通过遗传选育的手段,使窝产仔数大约增加了1.5头,仔猪断奶的日龄也相应地增加到平均为19~23 d。当每头母猪产仔数增加以后,由于初生活仔数的增加,有更多体重轻的仔猪出生,这将是生产者所面临的挑战。因此,对生产者来说,了解影响初生体重轻的仔猪一生的生产性能以及收益的因素是非常必要的。  相似文献   
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Objective: To evaluate a technique for midhumeral peripheral nerve blockade in the dog. Study Design: Cadaveric technique development; in vivo placebo‐controlled, prospective crossover study. Animals: Canine cadavers (n=38) and 8 clinically healthy, adult hound dogs. Methods: A technique for peripheral block of the radial, ulnar, musculocutaneous, and median nerves (RUMM block) was evaluated using cadaver limbs. Eight purpose‐bred, research dogs were anesthetized; a RUMM block was performed on each thoracic limb. One limb from each dog randomly received 0.5% bupivacaine and the opposite limb was assigned to receive sterile saline solution as a control. After recovery from anesthesia, skin sensation at selected dermatomes was evaluated for 24 hours using a mechanical stimulus. Weight‐bearing, conscious proprioception, and withdrawal reflex were also evaluated. One month after initial testing, each dog was reanesthetized and each limb received the opposite treatment. Results: Sensory thresholds were significantly increased over baseline measurements when compared with control limbs for all nerves. Complete sensory block was achieved in radial (15/16), ulnar (3/16), musculocutaneous (8/16), and median (11/16) nerves, using a mechanical stimulus of analgesia. Complete simultaneous block of all nerves was only obtained in 1 of 16 limbs. Conclusion: RUMM block resulted in desensitization of the skin in the associated dermatomes for 4–10 hours. Complete sensory block of the dermatomes supplied by the radial nerve was most consistent. Clinical Relevance: RUMM block may be an effective technique to provide adjunctive analgesia for dogs undergoing surgery of the distal aspect of the thoracic limb.  相似文献   
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