Genetic analysis of competition data on Icelandic horses

In a study of the possibility of using competition data in the genetic evaluation of Icelandic horses, data from competitions held in Iceland between 1999 and 2004 and in Sweden between 1998 and 2004 were analyzed to estimate the genetic parameters of competition performance traits. The data-sets from both countries included 18 982 records of 3790 horses in 379 different events. Two types of competition were included: sport competitions and gæðinga competitions performed on oval tracks and on a straight track. Each type of competition involves several disciplines in which the horses are ridden in the various gaits. The traits analyzed were two different measures of four-gait, five-gait and tölt, and one pace trait. In both the four-gait and five-gait tests the gaits walk, trot, tölt and gallop are exhibited. In the five-gait test, pace is also exhibited. The traits tölt and pace are performances of these single gaits. Highly correlated and similar traits were combined, and three new traits relating to tölt, four-gait and five-gait were formed. No large differences in means or standard deviations of traits were found between countries. All traits were approximately normally distributed. Genetic parameters were estimated using linear animal models including the fixed effects of sex, age and event for all traits, and the level of discipline was included for some traits. Random permanent environmental effects were also included. Estimated heritabilities were moderate to high, ranging from 0.18 to 0.21 for sport-competition traits, from 0.33 to 0.35 for gæðinga-competition traits and from 0.19 to 0.22 for combined traits. Estimated genetic correlations between different sport-competition traits varied from 0.63 to 0.96, and between the two gæðinga-competition traits it was estimated at 0.43. Genetic correlations between sport- and gæðinga-competition traits ranged from − 0.42 to 1.00. It was concluded that competition traits are suitable to include in genetic evaluations.     

Variation in somatic cell counts of milk samples from individual cows

Somatic cell counts of 2570 milk samples from 765 cows collected bimonthly from November 1975 to May 1976 were transformed to logarithmic values and analysed statistically. Components of variance were estimated as follows: Herds 0.033 (13 %), age groups 0.021 (8%), cows (within herds and age groups) 0.080 (31%), months 0.014 (6%), residual 0.107 (42%). Correction of actual cell counts for the influence of milk yield on the day of sampling led to only small changes in the magnitude of the various components. The coefficient of correlation between samples from the same cow was computed as 0.60 when the samples were from the same lactation, and 0.37 for samples from consecutive lactations.The proportionately small variation among herds as compared to the variation among cows of the same herd throws doubt on the efficiency of cell counting in samples of herd milk as a way of identifying cows with high cell counts.     

Deep-freezing of boar semen in plastic film 'cochettes'

The motility and membrane integrity of spermatozoa from nine boars frozen with a programmable freezing machine in plastic bags, 'cochettes', and in 'maxi-straws', in total doses of 5 x 10(9) spermatozoa/5 ml with glycerol (3%) used as cryoprotectant, were assessed after thawing. A computer-based cell motion analyser was used to evaluate sperm motility, while the integrity of the plasmalemma was assessed with fluorescent supravital dyes (C-FDA/PI). The fertilizing capacity of the semen frozen in the two containers was investigated by inseminating (AI) gilts. Pregnancy was monitored by Doppler-ultrasound, and the numbers of corpora lutea and viable embryos counted at slaughter, between days 30 and 38 after AI. The cochettes sustained the overall procedure of freezing/thawing (FT), with 30 min post-thaw (PT) sperm motility being significantly higher than for straws, 46.9 vs. 39.5%. The only significant difference in motility patterns detected when comparing the packages was a higher sperm velocity (VCL) in cochettes at 30 min PT. However, percentages of FT-spermatozoa with intact membranes, detected with the supravital probes, were higher in maxi-straws than in cochettes, 46.8 vs. 43.0% (P < 0.05). There were no significant differences found in fertilizing capacity between spermatozoa frozen in maxi-straws and those frozen in cochettes. The results indicate that although the deep-freezing of AI-doses of boar semen in large plastic bags is feasible, problems such as their inconvenient size for storage and inconsistent thawing must be solved before this type of container can be used for the commercial cryopreservation of boar semen.     

Effects of timing,duration, and intensity of simulated browsing on Scots pine growth and stem quality

This study examines a large number of structural and growth-related responses of young Scots pine in relation to simulated browsing from large herbivores. We combined different modes of intensity, timing, and duration of clipping for nine consecutive years from 2000 to 2008. Data on tree responses were collected yearly during this period, as well as in 2011, and were analyzed using ordination techniques and generalized linear models. A key result demonstrated is the serious effects of clipping on the youngest pines. Mortality was high when clipping started the first year, indicating that the trees are vulnerable at that stage, but after that increasing intensity and duration of clipping were the main causes of mortality. Among the different treatment factors, intensity of clipping had the largest influence on altering the final growth responses, some of the quality responses, and mortality. Timing of clipping was the most important factor for explaining the occurrence of the majority of responses related to stem structure. Duration of clipping had the largest effect on the responses that included repeated-measures data, such as height development and number of stems. We discuss the long-term consequences of browsing for the trees and the implications for forest management.     

Human neuroblasts migrate to the olfactory bulb via a lateral ventricular extension

The rostral migratory stream (RMS) is the main pathway by which newly born subventricular zone cells reach the olfactory bulb (OB) in rodents. However, the RMS in the adult human brain has been elusive. We demonstrate the presence of a human RMS, which is unexpectedly organized around a lateral ventricular extension reaching the OB, and illustrate the neuroblasts in it. The RMS ensheathing the lateral olfactory ventricular extension, as seen by magnetic resonance imaging, cell-specific markers, and electron microscopy, contains progenitor cells with migratory characteristics and cells that incorporate 5-bromo-2'-deoxyuridine and become mature neurons in the OB.     

Parasitoids (Hymenoptera, Ichneumonoidea) of Saproxylic beetles are affected by forest successional stage and dead wood characteristics in boreal spruce forest

The habitat requirements and effects of forest management on insects belonging to higher trophic levels are relatively unknown in forest ecosystems. We tested the effect of forest successional stage and dead wood characteristics on the saproxylic parasitoid (Hymenoptera, Ichneumonoidea) assemblage in boreal spruce-dominated forests in northern Sweden. Within each of nine areas, we selected three sites with different management histories: (1) a clear-cut (2) a mature managed forest and (3) an old-growth forest. Parasitoids were collected in 2003 using eclector traps mounted on fresh logs, which were either untreated (control), burned, inoculated with fungi, or naturally shaded, and on artificially-created snags.Both forest type and dead wood characteristics had a significant effect on parasitoid assemblages. Grouped idiobionts and some species, such as Bracon obscurator and Ontsira antica, preferred clear-cuts, while others, such as Cosmophorus regius (Hym., Braconidae) and other koinobionts, were associated with older successional forest stages. No single dead wood substrate was sufficient to support the entire community of parasitoids in any forest type, even when the regular host was present. In particular, snags hosted a different assemblage of species from other types of dead wood, with parasitoids of Tetropium spp. such as Rhimphoctona spp. (Hym., Ichneumonidae) and Helconidea dentator (Hym., Braconidae) being abundant. These results indicate that a diversity of dead wood habitats is necessary to support complete assemblages of beetle-associated parasitoids from early successional stages of dead wood and that parasitoids may be more sensitive to habitat change than their hosts.     

Effects of nitrogen-containing fertilizers on solubility and plant uptake of cadmium

In a pot experiment, three N-fertilizers, differing in NO^? ₃ and NH⁺ ₄; content, were compared in terms of their effects on the extractability of soil Cd in 1M ammonium acetate at pH 7 and on the uptake of native and added Cd by winter rape (Brassica napus L. var. oleifera Metzger). In another similar experiment the Cd-availability in soils receiving NPK-fertilizer applied in a concentrated, granulated form was compared to that in soils receiving a uniform application of dissolved NPK-fertilizer. Both loamy sand and clay soils were used. With the N-fertilizers levels of extractable soil Cd and plant Cd-contents were lowest in the nitrate of lime treatment, highest in the ammonium sulphate treatment and intermediate in the nitro-chalk treatment. The addition of 1 mg kg^?1 DW Cd to the soil increased Cd-levels but did not change the response pattern. There was a strong association between the effects of the various fertilizers on Cd availability and their effects on soil pH: the stronger the acidifying effect the higher the Cd availability. When applied at a low dose, granular NPK was more effective than dissolved NPK at enhancing plant uptake of Cd from both soils, but this was not the case when applied at a higher dose to the sand. The two forms of NPK differed little in their effect on extractable soil Cd. Plant uptake of Cd was greater from soils receiving granular NPK with a high Cd-content than from those receiving granular NPK low in Cd. In both experiments extractable Cd was taken up to a greater extent from the sand than from the clay. An increase in fertilizer dose generally resulted in an increase in levels of soil-Cd and in Cd concentrations in the plants.     

Modelling Acidification Effects on Coniferous Forest Soils

Two submodels for simulating the leaching of forest soils are described. SOILORG is used for O, E, and top B layers where Al(OH)₃ is absent and organic matter is the major base cation storage. SOILMIN cares for the rest of the profile where Al(OH)₃ control of Al is assumed and goethite provides most of the sulphate storage, clay mineral surfaces providing base cation storage. Results are presented from a test run for the period 1911 to 2030, based on data from a 260 cm deep soil profile in the SW of Sweden investigated 1990 and on a likely deposition scenario. Considering that the deposition of base cations exceeded the removal by stemwood in 1911 when the simulation started, the biologic acidification of the soil profile had reached a steady state before 1911 so that no additional acidification took place before 1930 and very little before 1950. After 1950 it was strongly enhanced by the increased acid deposition. In the mineral soil a considerable resistance against acidification is offered both by base cation exchange and sulphate adsorption, creating an acidification front which moved slowly down the B-horizon then accelerated, reaching the bottom of the profile in 1990. A deposition reduction by 2/3 during 1990–2010 will cause a partial recovery of pH, particularly in the deeper parts of the profile.     

The Effects of Peptide-Precipitating Lignosulphonic Acids on the Proteolytic Activity of Pepsin in Vitro and on the Response of Pigs to an Ulcer Inducing Diet

The inhibitory effect of peptide-precipitating lignosulphonic acids on the proteolytic activity of pepsin in vitro has been studied. When an unfractionated lignosulphonic acid preparation was used, total inhibition of the activity of 5 µg crystalline pepsin was obtained by addition of about 15 mg of lignosulphonic acids.The greatest inhibitory effect was seen with the high-molecular weight lignosulphonic acids, but an effect was also seen with middle-and low-molecular weight lignosulphonic acids.A reduction in the inhibitory effect was seen when the experiments were performed in the presence of arginine. The inhibition mechanism is discussed in relation to the peptide-precipitating ability of the lignosulphonic acids.No obvious protection against the appearance of stomach ulcers in four pigs receiving an ulcerogenic diet was seen.