Aerobic Training, But Not Creatine, Modifies Longissimus Dorsi Muscle Composition

The goal of this study was to investigate by means of an ultrasound examination the composition of the longissimus dorsi muscle in 12 purebred Arabian horses submitted to aerobic training for 90 days, with and without creatine supplementation. Creatine supplementation was carried out by daily administration of 75 g creatine monohydrate mixed into the ration during 90 days of training. Physical conditioning was conducted on a high-performance treadmill, and training intensity was stipulated by calculating the velocity at which blood lactate reaches 4 mmol/l, determined monthly for each animal. The individual intensity of physical force was established at 80% of velocity that resulted in a blood lactate level of 4 mmol/l. The cross-sectional area and the thickness of the layer of fat of the longissimus dorsi muscle were measured for each group at the end of 8 months of inactivity and after 30, 60, and 90 days of training without (control groups) or with creatine supplementation (experimental groups). The results showed that aerobic training combined with or without creatine supplementation caused significant longissimus dorsi hypertrophy and reduction in the thickness of the fat layer. No beneficial effect from prolonged creatine supplementation on the body composition of horses was detected.     

Farmer perspectives on cropping systems diversification in northwestern Minnesota

It is important to understandfactors that influence management decisionsthat determine the level of diversificationwithin cropping systems. Because of the widevariety of cropping systems within a region,our study focused on a single county (Marshall)in northwestern Minnesota. This county wasselected because it is in an area where farmerswere reevaluating their cropping practicesduring the 1990s in response to severe plantdisease outbreaks and economic stresses. Asurvey (n = 153) and follow-up interviews (n = 9)of representative farmers in Marshall Countyshowed that they were approaching theircropping systems management decisions underthese conditions through a dominant conceptualframework (scientific) and two secondaryconceptual frameworks (institutional andspiritual), which we termed mental causalmodels. The study illustrates the ways farmersdefine and make decisions affecting theircropping systems diversity under conditions ofagronomic and economic adversity. It alsochallenges agricultural professionals to expandtheir thinking about educational strategiesthat are sensitive to the varied perspectivesof farmers beyond just the scientific mentalcausal model.     

Selling appropriate development vs. selling-out rural communities: Empowerment and control in indigengous knowledge discourse

This paper looks at the languages of empowerment and control as they are expressed by authors writing about indigenous knowledge. We performed a content analysis on CIKARD News, a newsletter dealing with the concept of indigenous knowledge. This concept has become increasingly prominent in the discourse of alternative development, addressing issues of ecological sustainability and the empowerment of the rural poor. However, mediated by institutions that perpetuate global and local power asymmetries, the empowering potential of indigenous knowledge may be bypassed. Instead, officials, researchers, and practitioners may utilize this knowledge for their own perceived ends, however good their intentions. In addition, there is already evidence that an indigenous knowledge approach is seen by major agencies as beneficial for integrating poorer populations into the global economy. Our analysis suggests that tensions persist among and within the writings of these authors between the desire to empower and the tendency for development to control rural populations.William E. O'Brien is currently a doctoral student in Environmental Design and Planning at the Virginia Polytechnic Institute and State University in Blacksburg, Virginia. His masters and bachelors degrees are both in Geography; the masters also from Virginia Tech, the bachelors degree from Radford University. His research interests center around the use of indigenous knowledge in pastoral development and agroforestry, particularly in East Africa.     

Alternative pathways in the life history of Gracilaria gracilis (Gracilariales, Rhodophyta) from north-eastern Sicily (Italy)

The reproductive phenology of Gracilaria gracilis has been followed closely in a brackish water lake in Sicily. The life history of this red alga deviated from the typical Polysiphonia-type cycle and was characterized by the predominance of the tetrasporophytic phase over gametophytes, in situ development of germinated gametophytes and the presence of sterile pleustophytic thalli. Release of spherical agglomerates of cells produced by young tetrasporophytes was observed as well. Their ability to germinate forming new thalli appears to represent an alternative reproductive strategy of this organism. The population structure appears to reflect a predominance of the diploid phase except during the warmer summer season when only vegetative juveniles were found in the lake. Release and early stages of development of carpospores and tetraspores were critically observed in culture. A Dumontia type pattern of germination was observed for both types of spores, showing an erect thallus arising from a multicellular basal disk. Compared to tetraspores, carpospores are less readily released resulting in a subsequent delay in the development of new gametophytes.     

野人谷自然保护区珍稀濒危野生脊椎动物及其保护

据调查,发现湖北野人谷自然保护区分布有珍稀濒危野生脊椎动物82种,占保护区脊椎动物285种数的28.8%,其中兽类22种,鸟类43种,爬行类9种,两栖类7种。国家重点保护野生动物58种,中国濒危动物红皮书44种,国际贸易公约濒危野生动物61种。     

Effect of Acute Administration of Clenbuterol on Athletic Performance in Horses

The aim of the study was to determine the effect of clenbuterol on the anaerobic threshold of horses on a treadmill with increasing physical stress, measuring heart rate (HR) and blood levels of lactate, glucose, and insulin. Twelve Arabian horses were submitted to two physical tests separated by a 10-day interval. Clenbuterol (CL) at 0.8 μg/kg or saline (control—C) was administered intravenously 30 minutes before the test. The treadmill exercise test consisted of an initial warmup followed by a gradually increasing effort. There was no statistical difference in either V₂ or V₄ (velocity at which plasma lactate concentration reached 4 and 2 mmol/L, respectively) between the two experimental groups. For the CL group, V₂₀₀, V₁₈₀, V₁₆₀, and V₁₄₀ (velocity at which the rate heart is 140, 160, 180, and 200 beats/minute, respectively) decreased significantly. At rest as well as times 4, 6, and 10 minutes, insulin levels were higher in the group that received clenbuterol (P < .05). Contrary to what was expected, apparently, there was no improvement in aerobic metabolism in animals when given a therapeutic dose of the bronchodilator. The elevated heart rate observed could have been attributable to the stimulation of cardiac β₁ adrenoceptors and the increased insulin levels to the stimulation of pancreatic β₂ receptors.     

Pharmacokinetic properties of doxorubicin encapsulated in glutaraldehyde-treated canine erythrocytes.

Canine erythrocytes were loaded with the antineoplastic drug doxorubicin and then treated with 0.16% glutaraldehyde. This procedure has been previously shown to slow down the efflux of doxorubicin from erythrocytes and to result in the selective targeting of the carrier erythrocytes to liver. Three dogs were treated each with 2 different schedules of IV bolus administration of doxorubicin (0.4 mg/kg of body weight): free drug and doxorubicin encapsulated in glutaraldehyde-treated erythrocytes. The 2 treatments yielded consistent differences in the plasma pharmacokinetic properties of doxorubicin and of its only metabolite, doxorubicinol. A triphasic exponential decay of doxorubicin plasma concentrations was observed on injection of the free drug. Conversely, in the case of erythrocyte-encapsulated doxorubicin, 4 phases of plasma concentrations of doxorubicinol were found. The plasma concentrations of doxorubicinol, after a steady increase during the first hour, followed patterns of decay comparable to those of the parent drug. On the basis of the kinetic variables calculated with the 2 administration schedules, area under curve concentrations of plasma doxorubicin were 136 micrograms.h/L (free infusion) and 734 micrograms.h/L (erythrocyte-encapsulated drug). Significant alterations of hematologic and hematochemical factors were not observed in the 3 dogs during and after the 2 treatments. On the basis of our findings, doxorubicin-loaded and glutaraldehyde-treated erythrocytes may potentially be used in the treatment of systemic and hepatic tumors in dogs.