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41.
A.J.F Webster 《Livestock Production Science》1980,7(3):243-252
Metabolizable energy consumed by a growing animal is partitioned between heat production and gains in body tissues, principally protein and fat. The laws of growth that govern this partition are discussed. The apparent energy costs of protein and fat deposition in rats and pigs are about 53 kJ/g. Heat production is, however, related much more closely to total protein synthesis, most of which takes place in tissues other than ‘meat’. Ways and means of manipulating protein synthesis and the energy cost of growth by nutrition, anabolic agents and anti-microbial growth promoters are considered. 相似文献
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Boria PA Webster CR Berg J 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(3):232-234
A 5-year-old, castrated male, golden retriever was presented with a history of regurgitation. An esophagram revealed normal peristalsis with failure of the lower esophageal sphincter to open, supporting the diagnosis of esophageal achalasia. Prior to surgery, the dog developed megaesophagus. Heller's esophagomyotomy resolved the clinical signs and the esophageal dilation. 相似文献
44.
Webster MJ Goodband RD Tokach MD Nelssen JL Dritz SS Woodworth JC De La Llata M Said NW 《Journal of animal science》2003,81(8):2032-2040
We conducted two experiments comparing the use of extruded-expelled soybean meal (EESoy) to solvent-extracted soybean meal (SBM) in swine diets. In Exp. 1, the objective was to determine the optimal processing temperature of EESoy for nursery pig growth performance. Pigs (n = 330, 13.2 +/- 2.3 kg of BW) were fed a control diet containing SBM with added fat or one of five diets containing EESoy extruded at 143.3, 148.9, 154.4, 160.0, or 165.6 degrees C. All diets were formulated on an equal apparent digestible lysine:ME ratio. From d 0 to 20, no differences were observed (P > 0.32) in ADG or ADFI (average of 544 and 924 g/d, respectively). However, gain:feed ratio (G/F) improved (quadratic, P < 0.01, range of 0.56 to 0.60) with increasing processing temperature, with the greatest improvement at 148.9 degrees C. In Exp. 2, the objective was to determine the feeding value of EESoy relative to SBM with or without added fat for growing-finishing pigs in a commercial production facility. A total of 1,200 gilts (initially 24.5 +/- 5.1 kg of BW) was used, with 25 pigs per pen and eight replications per treatment. Dietary treatments were arranged in a 2 x 3 factorial, with two sources of soybean meal (SBM or EESoy) and three levels of added fat. Pigs were phase-fed four diets over the experimental period and added fat (choice white grease) levels were 0, 3.4, and 7% initially, with the added fat levels decreasing in the next three dietary phases. Energy levels were based such that the higher energy in EESoy (with or without added fat) was calculated to be equal to that provided by SBM with added fat. From 24.5 to 61.2 kg, pigs fed EESoy had greater (P < 0.07) G/F than those fed SBM. Increasing added fat in either EESoy- or SBM-based diets increased G/F (linear, P < 0.0003). From 61.2 to 122.5 kg, ADG and G/F were unaffected in pigs fed EESoy and/or increasing added fat (P > 0.10). For the overall growing-finishing period, ADG was unaffected (P > 0.61) by increasing energy density of the diet; however, ADFI decreased (P < 0.05) and G/F increased (P < 0.02, range of 0.37 to 0.40) as energy density increased with either EESoy or added fat. Carcass leanness was not affected by dietary treatment. These results indicate that EESoy should be extruded at 148.9 to 154.4 degrees C, and that increasing dietary energy density by using EESoy and/or added fat improves feed efficiency in finishing pigs reared in a commercial environment. 相似文献
45.
A.Bruce Webster 《中国家禽》2007,29(19):48-49
当发生禽流感时,对规定范围内家禽必须进行扑杀清群.目前使用比较普遍的清群方法有:颈椎脱臼、水基泡沫、投毒、气体致死等.…… 相似文献
46.
Prepurchase examinations are commonly used in the evaluation of sport horses. No data have been published concerning the use of traditional Chinese veterinary medical (TCVM) channel palpation with respect to the musculoskeletal status of sport horses for sale. The objective of the study is to summarize the results of channel evaluation when integrated with a Western examination in a series of prepurchase examinations. The prepurchase examination records of 235 sport horses were reviewed. The examined horses were presented as serviceable for the intended use. The examinations were performed by a single observer. The TCVM palpation examination and Western examinations, which often included radiography, infrared thermometry, diagnostic ultrasound, fiberoptic endoscopy, and diagnostic blood screens, were used to further evaluate the musculoskeletal system. The data were used to define the relationship between soundness, lameness, channel imbalance, and sale outcome. Over 6 years, 235 horses were examined. One hundred fifty-six (66%) were sound at their working gaits, and 79 (34%) had observable lameness. Two thirds of lame horses had palpable channel imbalance. Only a quarter of sound horses presented with palpable channel imbalance. Sound horses with no channel imbalance, that is, level channels, were most frequently sold, and lame horses with channel imbalance most frequently were not sold. Significantly more sound horses with level channels were sold as compared with sale outcome of sound horses with unbalanced channels. In conclusion, the TCVM channel examination is a useful component in the integrated prepurchase examination of sport horses. 相似文献
47.
Noah D. Cohen VMD MPH PhD DACVIM G. Kent Carter DVM MS DACVIM Jeffrey P. Watkins DVM MS DACVS Michael S. O'Conor BS MS 《Journal of Equine Veterinary Science》2006,26(10):462-474
The objective of this prospective study was to determine the association between presence of abnormal radiographic findings attributed to orthopedic disorders of development (ARF) with subsequent performance among yearlings in Texas. The study population was 348 yearlings offered for sale at the Texas Summer Yearling Sale during 2002 and 2003 for which presale radiographs of limbs were available for review. Radiographs of yearlings were reviewed and presence of ARF were recorded. Additionally, the following data were recorded for each horse: identifiers [name of dam, name of sire, hip number, and name (when available)], year of sale, state of birth, and sales price. Subsequent performance data were obtained for each horse at the conclusion of their 2nd and 3rd years of life. Results indicated that no ARF was significantly associated with performance outcomes. Lesions of the proximal dorsal aspect of the sagittal ridge of the 3rd metacarpus/metatarsus resulted in significantly lower sales prices than either horses without this ARF or horses without any ARF. In conclusion, multiple radiographic abnormalities of Thoroughbred yearlings were not associated with reduced performance during the first 2 years of the racing careers of horses studied. Presence of some abnormalities, however, may be associated with reduced sales price. 相似文献
48.
C. G. Webster B. A. Coutts R. A. C. Jones M. G. K. Jones S. J. Wylie 《Plant pathology》2007,56(5):729-742
The southwest Australian floristic region (SWAFR) is an internationally recognized 'hot spot' of global biodiversity and has an endangered flora. It represents a unique interface between an ancient ecosystem and a recent agroecosystem, providing the opportunity to investigate encounters where the recipient of the virus is an introduced crop and the donor a native plant and vice versa. Phylogenetic analysis of the virus coat-protein genes was used to study isolates of three potyviruses representing different 'new encounter' scenarios at this interface. The incidence, symptomatology, host range, non-persistent aphid transmission and considerable genetic diversity of the first indigenous virus described from the SWAFR, where it infects the native legume Hardenbergia comptoniana , and its potential to damage lupin, a locally important, newly introduced cultivated grain legume, was studied. The name Hardenbergia mosaic virus is proposed for this virus. Two other examples of 'new encounter' scenarios involving other legume-infecting potyviruses studied were: Passion fruit woodiness virus , which has been found only in Australasia, where it damages recently introduced species of Passiflora and legumes; and Bean yellow mosaic virus, which is not indigenous to Australia and was introduced recently to the SWAFR, where it infects a number of introduced legumes, but also damages the local native legume Kennedia prostrata . Isolates of the former had considerable genetic diversity consistent with the virus being indigenous, while isolates of the latter virus from K. prostrata had a low genetic diversity consistent with recent arrival. This research illustrates how introduced viruses can damage indigenous plants and indigenous viruses can damage introduced cultivated plants within this unique ecosystem, and how human activities can facilitate damaging 'new encounters' between plants and viruses. 相似文献
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