Genetic evaluation of cutting scores in horses

Cutting scores for 3399 horses representing 327 different sires from the NCHA World Championship Futurities of 1975 through 1983 were used to calculate heritability and yearly change in scores. The analysis yielded a heritability estimate of 19%±5%. Appropriate selection schemes, then, should be successful in bringing about an improvement in cutting score. The analysis of yearly trend, however, indicates that average cutting scores at NCHA futurities are decreasing by 0.78 points per year.     

Mastication and prescribed fire impacts on fuels in a 25-year old ponderosa pine plantation, southern Sierra Nevada

Due to increases in tree density and hazardous fuel loading in Sierra Nevadan forests, land management is focusing on fuel reduction treatments to moderate the risk of catastrophic fires. Fuel treatments involving mechanical and prescribed fire methods can reduce surface as well as canopy fuel loads. Mastication is a mechanical method which shreds smaller trees and brush onto the surface fuel layer. Little data exist quantifying masticated fuel beds. Despite the paucity of data on masticated fuels, land managers desire fuel loading, potential fire behavior and fire effects such as tree mortality information for masticated areas. In this study we measured fuel characteristics before and after mastication and mastication plus prescribed burn treatments in a 25-year old ponderosa pine (Pinus ponderosa C. Lawson) plantation. In addition to surface fuel characteristics and tree data collection, bulk density samples were gathered for masticated material. Regressions were created predicting masticated fuel loading from masticated fuel bed depth. Total masticated fuel load prior to fire treatment ranged from 25.9 to 42.9 Mg ha⁻¹, and the bulk density of masticated fuel was 125 kg m⁻³. Mastication treatment alone showed increases in most surface fuel loadings and decreases in canopy fuel loads. Masticated treatment in conjunction with prescribed burning reduced both surface and canopy fuel loads. Detailed information on fuel structure in masticated areas will allow for better predictions of fire behavior and fire effects for fire in masticated fuel types. Understanding potential fire behavior and fire effects associated with masticated fuels will allow managers to make decisions on the possibility of mastication to create fuel breaks or enhance forest health.     

德国牧羊犬协会繁殖价值估算

1998年5月23日至24日,德国牧羊犬协会在莱比锡召开的会员大会上一致通过了实施繁殖价值的估算,同时通过了防治髋关节异常的繁殖计划.     

Wedge-shaped vertebral formation as the cause of leg weakness syndrome in swine--a case report

We report about two cases of hemivertebrae in pigs. The malformations appeared in the T2/3, respectively in the T10. One case showed clinical apparent signs, namely ataxia and leg weakness. The productivity of the affected pig was reduced. Both cases are of unclear genesis. A hereditary predisposition could not be proved.     

Ulysses radio and plasma wave observations in the jupiter environment

The Unified Radio and Plasma Wave (URAP) experiment has produced new observations of the Jupiter environment, owing to the unique capabilities of the instrument and the traversal of high Jovian latitudes. Broad-band continuum radio emission from Jupiter and in situ plasma waves have proved valuable in delineating the magnetospheric boundaries. Simultaneous measurements of electric and magnetic wave fields have yielded new evidence of whistler-mode radiation within the magnetosphere. Observations of aurorallike hiss provided evidence of a Jovian cusp. The source direction and polarization capabilities of URAP have demonstrated that the outer region of the lo plasma torus supported at least five separate radio sources that reoccurred during successive rotations with a measurable corotation lag. Thermal noise measurements of the lo torus densities yielded values in the densest portion that are similar to models suggested on the basis of Voyager observations of 13 years ago. The URAP measurements also suggest complex beaming and polarization characteristics of Jovian radio components. In addition, a new class of kilometer-wavelength striated Jovian bursts has been observed.     

Evaluation of different media and a BGM cell culture assay for isolation of Borrelia burgdorferi sensu lato from ticks and dogs

A co-culture assay for isolation of Borrelia burgdorferi sensu lato (sl.) from naturally infected ticks and dogs suspected of Lyme borreliosis (LB) was evaluated using buffalo-green-monkey (BGM) cells as the mammalian component. Four different media were tested for their ability to provide sufficient growth conditions for spirochetes and BGM cells. A total of 176 Ixodes ricinus ticks and 268 specimens from 98 dogs were used to compare cell-free culture with the BGM co-culture. A 1:1 mixture of Barbour-Stoenner-Kelly medium (BSK) and Eagle's minimum essential medium (EMEM) supported the growth of the two test strains, B. burgdorferi sensu stricto B31 and B. valaisiana VS116 to the same extent as BSK medium and the growth as well as the viability of BGM cells in this medium were the same as in EMEM. Using the 1:1 mixture of BSK and EMEM, borrelial growth measured in co-culture with BGM cells did not differ significantly from corresponding values obtained in cell-free cultures. In cell-free culture the isolation rate of B. burgdorferi sl. from ticks was significantly higher in BSK/EMEM 1:1 than in BSK medium (P < 0.01). Co-culture with BGM cells had no significant influence on the isolation rate of borreliae from ticks. However, a significant amount of isolates were obtained by one of the procedures only. Analysing canine specimens accordingly, spirochetes were grown from the blood of one dog after four weeks in BGM cell co-culture. The isolate was classified as B. afzelii by PCR-coupled restriction fragment length polymorphism analysis.     

Genetic similarity of natural populations and plantations of Pinus roxburghii Sarg. in Nepal

? Genetic structures of five population pairs each consisting of one natural population and one neighbouring plantation of Pinus roxburghii Sarg. in Nepal were assessed using nuclear (nSSRs) and chloroplast microsatellite loci (cpSSRs).

? The mean number of alleles at nSSRs loci in natural populations was 5.0 compared to 4.93 in plantations while the average observed heterozygosities were the same in both groups (H ₀ = 0.50). Most of the alleles were common to all the populations, indicating that the populations correspond to a single genetic entity. Similarly forty-seven haplotypes were observed in natural populations compared to fifty haplotypes in plantations. Mean haplotype diversities of natural populations (0.953) and plantations (0.955) were very similar. Genetic diversity of Pinus roxburghii was relatively high with low or no evidence of inbreeding while genetic differentiation among all populations was very low (about 1%).

? The very low differentiation among natural populations indicates efficient long-distance gene flow among populations resulting in homogeneous genetic structures at least at selectively neutral loci. Even though the harvest and production of seeds and seedlings was largely uncontrolled, genetic structures of most plantations show no signs of reduced variation, inbreeding or other negative effects compromising the adaptedness or adaptability of planted forests.

     

Activity Behavior of Horses Housed in Different Open Barn Systems

Housing conditions do not frequently meet the natural needs of horses. German and Swiss studies have shown that merely 16% of horses are kept in group housing systems, but even these vary greatly with different effects on horses’ behavior. The objective of the survey was to determine whether horses show increased activity in barns with various options for movements and functional elements. Free movement stables allow horses to live within a herd, to decide whether to be outside or inside the herd, and to enable them fresh air supply. Data from 25 horses kept in three different open barns (O1–O3) were compared with that from two active barns with functional elements (active barn 1 and active barn 2), for example, automatic feeder, with five horses each. Activity-Lying-Temperature-pedometers fastened to a rear leg of each horse were used to measure activity. Animal data were recorded throughout a test period of 10 days per barn. The results showed a median of 46 to 68 mean daily activity impulses per 10 minutes for horses in stables O1 to O3. In stables active barn 1 to active barn 2, this measure was exceeded considerably with medians of 77 and 151. The activity impulses in the stable systems were significantly different at an error level of α = 0.05. These results support previous studies and show that activity of horses depends on their opportunities for moving. The sectioning of a stable, placement of functional elements, and feeding frequency have considerable effects on the activity level of the horse. It is useful to integrate different functional areas in a group housing system.