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981.
To assess the effects of flax addition and flax processing on feedlot performance and carcass characteristics, 128 yearling beef heifers (360 +/- 14 kg of initial BW) were blocked by weight and assigned randomly to feedlot diets that included no flax (control), whole flax (WHL), rolled flax (RLD; 1,300 microm), or ground flax (GRD; 700 microm). Heifers were fed a growth diet (31% corn, 30% corn silage, 18% barley malt pellets, 14% alfalfa, 4% linseed meal, and 3% supplement; DM basis) for 56 d, after which they were adapted to a finishing diet (79% corn, 7% corn silage, 7% alfalfa, 4.75% linseed meal, and 2.25% supplement; DM basis). In WHL, RLD, and GRD, flax replaced all linseed meal and partially replaced corn at 8% of diet DM. All diets provided 0.5 mg of melengestrol acetate, 2,000 IU of vitamin E, and 232 mg of monensin per heifer daily. Cattle were slaughtered by block after 96, 97, and 124 (2 blocks) d on feed. At 24 h postmortem, carcass data were collected, and a portion of the loin was removed, vacuum-packaged, and aged for 14 d. After aging, 2 steaks were removed from each loin for Warner-Bratzler shear force measurement, sensory panel evaluation, and fatty acid analysis (approximately 100 g of muscle was collected). Flax inclusion (WHL, RLD, and GRD vs. control) did not affect DMI (P = 0.79), fat thickness over the 12th rib (P = 0.32), or LM area (P = 0.23). Flax inclusion increased ADG (P = 0.006), G:F (P = 0.006), and USDA yield grade (P = 0.01). Flax processing (RLD and GRD vs. WHL) increased ADG (P = 0.05), G:F (P = 0.08), and apparent dietary NEm and NEg (P = 0.003). Muscle from heifers fed flax had greater phospholipid 18:3n-3 (P < 0.001), 20:5n-3 (P < 0.001), 22:5n-3 (P < 0.001), and 22:6n-3 (P = 0.02) fractions, and greater neutral lipid 18:3n-3 (P < 0.001). Feeding 8% flax to feedlot heifers increased gain and efficiency, and processing flax increased available energy and resulted in increased efficiency of gain. Feeding 8% flax also increased levels of n-3 fatty acids in fresh beef.  相似文献   
982.
983.
本试验采集泌乳期奶牛的瘤胃液,按2×4×2因子设计,用体外尼龙袋发酵技术研究了60:40和50:50两种精粗比日粮,棉籽油作为能源在奶牛日粮中分别添补0%、2.5%、5%、10%和在日粮中分别添加0%、0.5%的酵母培养物及其互作对体外干物质降解率的影响。体外实验结果表明,对于高产泌乳期奶牛而言,精粗比为60:40的奶牛日粮其干物质降解率高于50:50的精粗比日粮;奶牛日粮中添补植物油和酵母培养物均能显著提高体外干物质降解率(P<0.05);日粮精粗比与能量的互作对6小时的干物质降解率有显著影响(P<0.01);日粮能量添补与酵母培养物添补亦对体外干物质降解率有显著互作影响(P<0.05);而日粮精粗比与酵母培养物添补的互作影响则不明显;植物油作为奶牛日粮能源其添补量不宜超过10%。  相似文献   
984.
An abattoir survey was carried out on 1657 cattle to determine the incidence and parameters of teat and udder papillomas and their causal viruses. Recent research has characterised six different bovine papillomaviruses of which three have been found to be particularly associated with teat tumours. Of the population studied 37.3 per cent had teat warts and 86.2 per cent of these had multiple infections; 28.4 per cent had papillomas attributed to bovine papillomavirus 1, 88.5 per cent to bovine papillomavirus 5 and 92.3 per cent to bovine papillomavirus 6. There was no predilection site between teats. Herefords and their crosses dominated the breed incidence and showed the highest numbers of warts but it was not possible to make a realistic comparison with other breeds. Dairy cattle were poorly represented. Bovine papillomavirus 4 was never found and from this it was concluded that there is no association between alimentary and teat papillomas. The implications of these findings in terms of prophylaxis and control are discussed.  相似文献   
985.
The purpose of this study is to evaluate the internet-use among pet owners seeing a veterinary oncologist. Over a two-month period, 137 questionnaires were collected at three specialty hospitals around a large urban city. Approximately 85% of respondents reported using the internet to research their pet's condition and/or treatment. A search engine was the most employed means however veterinary university websites were considered to provide the most accurate information. The odds of owners who researched their own health condition online researching their pet's condition was 4.3 (95% CI: 1.2–23.1, p < .021) times as high as owners who did not research their own health condition. The odds of owners who have been to their oncologist previously to research their pet's condition was 4.7 (95% CI: 26.9.3, p < .001) times as high than owners who have not been to an oncologist previously. Oncologists should be aware internet use among pet owners appears common and further research to assess the accuracy and readability of veterinary medical websites appears indicated.  相似文献   
986.
Fumaric and sorbic acid as additives in broiler feed   总被引:2,自引:0,他引:2  
The aim of the experiment was to study the effect of dietary organic acids, fumaric and sorbic, on nitrogen corrected apparent metabolisable energy (AME(N)), metabolisability of nutrients, endogenous losses and performance on young broiler chickens. A total of 56 male Ross broilers were used in a growing experiment from 14 to 30d age. Seven experimental wheat-based (655g/kg) diets were formulated. The control diet did not contain organic acids. The other six diets were produced with the addition of fumaric or sorbic acids, replacing 0.5% , 1.0% or 1.5% of the wheat. The organic acid supplemented diets contained higher levels of AME(N) compared to the control diet. Overall, birds offered organic acids had lower feed intake. Dietary organic acids did not significantly affect weight gain or feed efficiency, however, birds offered supplemented diets had lower numbers of Lactic acid bacteria and Coliforms in the ileum and caeca. Birds offered organic acids had lower levels of endogenous losses compared to control fed birds. There was a negative relationship between AME(N) of the diets and excreted endogenous losses, measured as sialic acid. It can be concluded that the decrease in secretions from the gastrointestinal tract in the presence of fumaric and sorbic acids may be a mechanism involved in the mode of action of dietary organic acids.  相似文献   
987.
The diet of approximately three billion people worldwide is nutrient deficient and most of the world’s poorest people are dependent on staple food crops as their primary source of micronutrients. One component of the solution to nutrient deficiencies is collaboration among plant breeders, cereal chemists and nutritionists to produce staple crop cultivars with increased mineral nutrient concentration. Sixty-three historical and modern wheat cultivars were evaluated for grain yield and concentration of calcium, copper, iron, magnesium, manganese, phosphorus, selenium, and zinc. While grain yield has increased over time, the concentrations of all minerals except calcium have decreased. Thus a greater consumption of whole wheat bread from modern cultivars is required to achieve the same percentage of recommended dietary allowance levels contributed by most of the older cultivars. The decrease in mineral concentration over the past 120 years occurs primarily in the soft white wheat market class, whereas in the hard red market class it has remained largely constant over time. This suggests that plant breeders, through intentional selection of low ash content in soft white wheat cultivars, have contributed to the decreased mineral nutrient concentration in modern wheat cultivars. These results contradict the theory that there exists a genetically based, biological trade-off between yield and mineral concentrations. Therefore, using the abundant variation present in wheat cultivars, it should be possible to improve mineral concentrations in modern cultivars without negatively affecting yield.  相似文献   
988.
OBJECTIVE: To evaluate a combined cycloablative and gonioimplantation technique for treatment of glaucoma in dogs. DESIGN: Retrospective study. ANIMALS: 18 adult dogs with glaucoma. PROCEDURE: Medical records of dogs that received a valved gonioimplant and a cyclodestructive procedure (cyclocryoablation or diode laser cyclophotocoagulation) during a 6-year period were reviewed. Retention of vision and intraocular pressure control were assessed, as well as number and nature of complications. RESULTS: 19 eyes of 18 dogs received a valved gonioimplant and either cyclocryoablation (n = 12) or diode laser cyclophotocoagulation (7). At > or = 1 year after surgery, 11 of 19 eyes had vision and 14 of 19 eyes had intraocular pressure < 25 mm Hg. Two dogs (2 eyes) were lost to follow-up 3 and 6 months after surgery. Despite the alternative route for aqueous humor flow created by the gonioimplant, 7 eyes had increased intraocular pressure (27 to 61 mm Hg) < 24 hours after surgery. Other complications included excessive intraocular fibrin, focal retinal detachment, corneal ulcer, retinal hemorrhage, cataract, and implant migration. CONCLUSIONS AND CLINICAL RELEVANCE: Combined cycloablation and gonioimplantation appears to be a promising technique for retention of vision and control of intraocular pressure in dogs with glaucoma.  相似文献   
989.
Anal sac squamous cell carcinoma is rare in dogs. Five cases have been previously reported, treatment of which involved surgery alone. This report describes three further cases of canine anal sac squamous cell carcinoma which underwent medical (meloxicam) management alone, resulting in survival of up to seven months. No metastases were identified. Squamous cell carcinoma, although extremely uncommon, should be considered as a possible differential diagnosis when a dog is presented for investigation of an anal sac mass.  相似文献   
990.
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