Estradiol-17 beta effects on lipid metabolism of adipose tissue in nutritionally induced lean and obese ovariectomized ewes.

Nutritionally manipulated lean (68 kg) and obese (87 kg) ovariectomized ewes were administered estradiol-17 beta (E2) or sham implants. Ewes individually had ad libitum access to corn silage. Rates of de novo lipogenesis, palmitate esterification, and glycerol and fatty acid release were determined with slices of subcutaneous adipose tissue at 0, 5, and 30 d after implantation. Condition and E2 interacted over time (linear, P less than .12; quadratic, P less than .05) to affect intake. Lean ewes implanted with E2 decreased intake initially after implantation, whereas obese ewes implanted with E2 decreased intake later after implantation. The linear effect of time x condition x E2 interacted (P less than .02) for lipogenesis. Lipogenesis was inhibited in both the lean and obese ewes implanted with E2. Lean compared with obese ewes without E2 had increased lipogenesis at a faster rate over time. Esterification increased (linear, P less than .01) in the lean ewes and decreased (quadratic, P less than .01) in the obese ewes over time. A time x E2 interaction occurred for esterification (P less than .02). Glycerol and fatty acid release were variable over time within condition and E2. A 48-h adipose tissue culture determined the effect of E2 on lipid metabolism. Estradiol-17 beta decreased (P less than .05) lipogenesis, decreased (P less than .08) esterification, and maintained fatty acid and glycerol release. Data in vivo and in culture indicated that E2 acted to decrease de novo lipogenesis and palmitate esterification and had little or no effect on lipolysis.     

Food safety and residues in Australian agricultural produce

SUMMARY A brief history of food safety in Australia in the context of the development of scientific knowledge is presented. Australia's food and food commodity residue and contamination surveillance and monitoring programs are outlined. Although chemical residues are perceived as a major health risk by the general community, the risk of food causing illness or death because of chemical residues is low. The major threat to human health from food is microbiological contamination, in terms of deaths, sickness and economic loss. The emerging influences in food safety are scientific and technical developments, deregulation, social and demographic factors, and the media. The risk of disruption of domestic and export markets by food safety issues is considerable. The emergence of international standards for food production and processing will enable commercial contractual arrangements to minimise the frequency of disruptive food safety incidents.     

Tasco-Forage: II. Monocyte immune cell response and performance of beef steers grazing tall fescue treated with a seaweed extract

Effects of applying Tasco-Forage, an Ascophyllum nodosum seaweed-based product prepared by a proprietary process, to endophyte (Neotyphodium coenophialum [Morgan-Jones and Gams] Glenn, Bacon, and Hanlin)-infected and endophyte-free tall fescue (Festuca arundinacea Schreb.) were studied in each of 3 yr (1995, 1996, and 1997) in Virginia and in 1996 and 1997 in Mississippi. There were 48 steers at each location in each year (n = 240) in a 2 x 2 x 2 factorial arrangement with two replications at each location. Steers in Virginia were Angus and Angus x Hereford with initial weights of 245 kg (SD = 20), 234 kg (SD = 9), and 265 kg (SD = 5) in yr 1, 2, and 3, respectively. Steers in Mississippi were 3/4 Angus and 1/4 Brahman and weighed 230 kg (SD = 8) and 250 kg (SD = 2) in yr 2 and 3, respectively. Tasco (3.4 kg/ha) was dissolved in water and applied to pastures in April before grazing was begun and again in July at the same rate. The grazing period was from mid-April to late September or mid-October. Total gains were higher (P < 0.05) for steers grazing uninfected than for those grazing endophyte-infected tall fescue. Rectal temperatures were increased (P < 0.05) due to endophyte infection at both locations; Tasco application decreased temperature of steers grazing infected fescue in Virginia (interaction, P < 0.07) but increased temperatures of steers grazing infected fescue in Mississippi (interaction, P < 0.05). Presence of the endophyte resulted in rough hair coats and loss of hair color, but the effect was partially offset (P < 0.05) by Tasco application in Virginia in 1995. Both monocyte phagocytic activity (all years and locations) and major histocompatibility complex class II expression (1995 only) were decreased (P < 0.05) in steers due to endophyte infection, but this effect was reversed (P < 0.05) by application of Tasco to pastures. Application of the extract from A. nodosum seems to have use in alleviating adverse effects of endophyte on immune function and may improve hair coat condition in cattle grazing infected fescue, but effects on rectal temperature varied due to location.     

新年祝辞

全国兽医药品行业的全体同仁： 新年好! 在兽药事业发展和改革取得显著成绩的进程中，我们迎来了新的一年。值此辞旧迎新之际，我谨代表中国兽医药品监察所，向全国工作在兽药管理、监察、科研、生产、检验、销售一线的全体同仁致以诚挚的问候和节日的祝福!对所有关心、支持和帮助我们工作的各位领导和朋友们表示衷心的感谢!衷心地祝愿大家在新的一年里，工作顺利，身体健康，阖家幸福，万事如意!     

团结协作 共同努力推动我国动物保健品事业的健康发展--在中国动物保健品协会第四届会员代表大会上的讲话

各位代表、各位来宾、同志们: 首先请允许我代表中国兽医药品监察所对本次代表大会的召开表示衷心的祝贺!     

Ultrastable mesostructured silica vesicles

A family of mesoporous molecular sieves (denoted MSU-G) with vesiclelike hierarchical structures and unprecedented thermal (1000 degreesC) and hydrothermal stabilities (more than 150 hours at 100 degreesC) associated with high SiO4 cross-linking was prepared through a supramolecular assembly pathway that relies on hydrogen bonding between electrically neutral gemini surfactants of the type CnH2n+1NH(CH2)2NH2 and silica precursors derived from tetraethylorthosilicate. The vesicle shells are constructed of one or more undulated silica sheets that are about 3 nanometers thick with mesopores (average diameters from 2.7 to 4.0 nanometers) running both parallel and orthogonal to the silica sheets, which makes the framework structure bicontinuous and highly accessible. Catalytic metal ion centers [for example, Ti(IV) and Al(III)] have been incorporated into the framework with the retention of hierarchical structure.     

应用MapInf0软件制作草地畜牧业各类专题统计地图的初步探讨

以青海省达日县建设乡为例,简要介绍了应用MapInfo软件制作草地畜牧业各类专题统计地图的主要过程和基本方法。     

Bodyweights and growth rates of spring- and autumn-born Thoroughbred horses raised on pasture

AIM: To examine the growth of spring- and autumn-born Thoroughbred foals raised on pasture.

METHODS: Bodyweight and growth rates were measured in pasture-raised Thoroughbred horses, born in either spring (n=56) or autumn (n=7), from birth to approximately 13 and 17 months of age.

RESULTS: Birthweight tended to be lower in autumn- than spring-born foals (54.4, SD 7.92 kg vs 57.3, SD 5.90 kg; p=0.08). Between birth and 6 months of age, there was no difference in growth rate at equivalent ages between horses born in spring and autumn. Spring-born horses, which were weaned in the autumn, had lower post-weaning growth rates than autumn-born horses that were weaned in the spring. At time of the late yearling sales (March–April) in the Southern Hemisphere, unadjusted mean bodyweights of autumn-born horses (379.3, SD 24.8 kg) were lower (p=0.017) than those of the spring-born horses (437.2, SD 35.3 kg), although values in the autumn-born horses were all within two standard deviations (SD) of the mean of the spring-born animals. When adjusted for the covariates of birthweight and gender, the difference between spring- and autumn-born horses at that time was not significant (p=0.25).

CONCLUSIONS AND CLINICAL RELEVANCE: Some autumn-born foals could be marketed for late yearling sales in the Southern Hemisphere, on the basis of bodyweight. Furthermore, they might also be competitive in the Northern Hemisphere industry (sales or racing), as they would be competing against horses of the same official age.