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91.
92.
The world's peat resources are diminishing rapidly—a fact that is causing anxiety in some countries. Project ‘Telma’, initiated by IUCN and IBP, is concerned with international cooperation in the conservation of peatlands (mires). Because peatlands play a key rôle in certain biogeochemical cycles (especially the hydrological and carbon cycles), interest is being expressed in the part they may have in maintaining ecological balance in some regions, and thus in the need for a conservation policy for peatlands. But further research is required on this function of peatlands. However, the scientific argument for conserving them is more definitive and is largely based on the fact that they comprise an important source of ecological information. Some of the diversity and intrinsic importance of this information is demonstrated by studies of the European sub-group of boreal mires. The Telma classification was devised as a framework for gathering information for preparing lists of sites of international significance for science and education. 相似文献
93.
M M LeBlanc T Tran J L Baldwin E L Pritchard 《Journal of the American Veterinary Medical Association》1992,200(2):179-183
Effects of farm management, breed, mare age, gestation duration, and climatologic factors on colostral specific gravity, colostral IgG concentration, and foal serum IgG concentration were evaluated. Climatologic variables measured were daily maximal, minimal, and mean air temperature, precipitation, average relative humidity, and total solar radiation. Presuckle, postpartum colostrum samples were collected from 140 Standardbred, 94 Thoroughbred, and 59 Arabian mares from January through June during 1985 and 1986. Thoroughbred (farm A, n = 61; farm B, n = 33) and Arabian (farm C, n = 45; farm D, n = 14) mares were located in Ocala, Fla; Standardbred mares (farm E) were in Montgomery, NY. Mares from farms A, B, D, and E foaled in box stalls, and mares from farm C foaled in sand paddocks. Mares with premature lactation greater than 12 hours were not included in the study. Foals were clinically normal at birth and suckled colostrum without assistance within 2 hours of parturition. Specific gravity of presuckle colostrum samples was measured by use of an equine colostrometer. Blood samples were collected 18 hours after parturition from 253 of the 293 foals (n = 45, 25, 32, 13, 138 on farms A through E, respectively) to determine serum concentration of IgG. The IgG concentrations in colostrum and serum were measured by single radial immunodiffusion. Data were analyzed by multiple regression or chi 2 analysis. The most important determinants of foal serum IgG concentration were the IgG content and specific gravity of presuckle colostrum samples (P less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
94.
The relationships among body weight, body composition, and intramuscular fat content in steers 总被引:1,自引:0,他引:1
Angus steers of known age (265 +/- 17 d) and parentage were used in a 2-yr study (yr 1, n = 40; yr 2, n = 45) to evaluate the relationship between percentage of i.m. fat content of the longissimus dorsi at the 12th rib and carcass characteristics during growth of nonimplanted steers. Steers were sorted by age and EPD of paternal grandsire for marbling into high- and low-marbling groups so that steers with varying degrees of genetic potential for marbling were evenly distributed across slaughter groups. All steers were fed a 90% concentrate corn-based diet. Steers were allotted to five slaughter groups targeted to achieve hot carcass weights (HCW) of 204, 250, 295, 340, and 386 kg over the course of the feeding period. Data were analyzed as a completely random design with a factorial arrangement of treatments (year, marbling group, and slaughter group). Marbling group did not affect backfat, LM area, yield grade (YG), or marbling score. Regression equations were developed to quantify the change in carcass characteristics and composition over slaughter groups. Hot carcass weight increased in a linear fashion and differed (P < 0.01) among the slaughter groups as anticipated by design. Yield grade followed a quadratic upward pattern (P < 0.01) as HCW increased. Slaughter group affected the degree of marbling linearly (P < 0.01). There were no slaughter group x marbling group interactions, indicating that no differences occurred in the pattern of marbling attributable to paternal grandsire EPD. Carcasses expressed small degrees of marbling at 266 kg of HCW and obtained a YG of 3.0 at 291 kg of HCW. Fractional growth rates decelerated with increasing HCW. Greater advances in marbling relative to total carcass fatness occurred at HCW less than 300 kg. Management practices early in growth may influence final quality grade if compensatory i.m. fat content development does not occur. 相似文献
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96.
Ehrhart NP Hong L Morgan AL Eurell JA Jamison RD 《American journal of veterinary research》2005,66(6):1039-1045
OBJECTIVE: To determine whether sustained release of transforming growth factor (TGF)-beta1 from a gelatin hydrogel would enhance bone regeneration in critical-sized long-bone defects and overcome inhibitory effects of preoperative irradiation. ANIMALS: 24 adult New Zealand White rabbits. PROCEDURE: Rabbits were allocated to 2 groups. Twelve rabbits received localized megavoltage radiation to the right ulna by use of a cobalt 60 teletherapy unit, and 12 rabbits received no irradiation. Then, a 1.5-cm defect was aseptically created in the right ulna of each rabbit. Gelatin hydrogel that contained 5 microg of adsorbed recombinant-human (rh)TGF-beta1 was placed in the defect of 12 rabbits (6 irradiated and 6 nonirradiated), and the other 12 rabbits received hydrogel without rhTGF-beta1. Rabbits were euthanatized 10 weeks after surgery. New bone formation within the defect was analyzed by use of nondecalcified histomorphometric methods. A 1-way ANOVA was used to compare differences among groups. RESULTS: New bone formation within the defect was significantly greater in TGF-beta1-treated rabbits than in rabbits treated with hydrogel carrier alone. Local delivery of rhTGF-beta1 via a hydrogel carrier in irradiated defects resulted in amounts of bone formation similar to those for nonirradiated defects treated by use of rhTGF-beta1. CONCLUSIONS AND CLINICAL RELEVANCE: Local delivery of TGF-beta1 by use of a hydrogel carrier appears to have therapeutic potential for enhancing bone formation in animals after radiation treatments. IMPACT FOR HUMAN MEDICINE: This technique may be of value for treating human patients at risk for delayed bone healing because of prior radiation therapy. 相似文献
97.
Ortiz-Pelaez A Pritchard DG Pfeiffer DU Jones E Honeyman P Mawdsley JJ 《Veterinary journal (London, England : 1997)》2008,176(2):177-181
The objective of this study was to test calf mortality as an indicator of on-farm welfare and its use for welfare targeted surveillance. Calf mortality data were retrieved for three UK counties to estimate calf mortality rates at holding and county level. A selection criterion based on upper quartiles of calf mortality for the county of concern was defined. Its predictive ability was tested in a field study. The death risk of calves less than 6 months of age in 2002 was 1.76% in Inverness, 5.83% in Cheshire and 4.8% in Norfolk. Fifty-two welfare inspections matched by parish were conducted between October 2004 and January 2005. The positive predictive value was 26.92% and the negative predictive value was 65.38%. The addition of herd type, county and membership to an assurance scheme improved the predictive value. This study shows that calf mortality can be the starting point to design targeted welfare inspections in countries with centralized animal data recording systems. 相似文献
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100.
Relationships between fry color and sugar concentration in stored Russet Burbank and Shepody potatoes 总被引:1,自引:0,他引:1
Relationships between french fry color and sugar composition of Russet Burbank and Shepody potatoes harvested at various chemical maturities (i.e., sucrose concentrations) and exposed to various temperature regimes during 8 to 9 months storage were examined. Combined data from 3 years of study showed fry color to be more closely associated with glucose during 8 C storage for Russet Burbank (r2=0.65) and Shepody (r2=0.62) than with fructose, total reducing sugars, sucrose, or total sugars. Glucose > 1.6 mg g?1 in Russet Burbank and > 1.2 mg g?1 in Shepody resulted in fries which were too dark to be eligible for maximum bonus paid by processors for good color. Russet Burbank harvested with sucrose > 3.1 mg g?1 and Shepody harvested with sucrose > 1.6 mg g?1 and preconditioned for 14 d at 15 C before storage at 8 C accumulated enough glucose in storage to result in fries which were darker than was acceptable for maximum bonus payment. Preconditioning at 15 C for 70 d was necessary to prevent Russet Burbank with sucrose of 3.9 mg g?1 at harvest from accumulating unacceptably high glucose during storage. Glucose determined with enzymatic test strips was in close agreement with that by HPLC for both cultivars. The test strips could be used to estimate fry color of Russet Burbank. 相似文献