Millettia ferruginea from southern Ethiopia: Impacts on soil fertility and growth of maize

Growing agricultural crops under Millettia ferruginea (Hochst.) Baker, a tree that is endemic to Ethiopia, is an age-old practice in the country, but the beneficial effects of the tree on crops have not been scientifically quantified. To achieve this, four isolated and nearly identical Millettia trees growing on similar site conditions were selected and canopy coverage of each tree was divided into four radial transects. Four plots of 0.5 × 0.5 m were established on each radial transect at 0.5 to 1, 2.5 to 3, 4.5 to 5, and 6.5 to 7 m away from the tree bases. The control plot was established at 29.5 to 30 m. Composite soil samples from each of the four plots located at a comparable distance and at two soil depths, 0 to 10 and 20 to 30 cm, were collected and analyzed. The level of surface soil P, organic C, exchangeable base-forming cations and cation exchange capacity were all significantly higher (P < 0.000 to P < 0.015) under the trees than in the open field. Nutrient levels declined with depth and increasing distances from the tree trunk. Soil pH values did not show significant horizontal or vertical variations in all the soil samples analyzed. Maize plants grown on soils collected from underneath Millettia trees resulted in significantly better growth responses and higher dry matter yield as compared to the control (P < 0.001). Socioeconomic studies indicated that Millettia trees have good standing in the region both because of their desirable biological characteristics and because of their economic benefits.This revised version was published online in November 2005 with corrections to the Cover Date.     

Studies of Enteric Pathogens and γ-Globulin Levels of Neonatal Calves in Sweden

Viring, S., S.-O. Olsson, S. Alenius, U. Emanuelsson, S.-O. Jacobsson, B. Larsson, N. Linde and A. Uggla: Studies of enteric pathogens and γ-globulin levels of neonatal calves in Sweden. Acta vet. scand. 1993, 34, 271-279.– Faecal and blood samples were taken from 10-30% of calves, 36 hours to 14 days old, in 47 dairy herds in different regions of Sweden from September 1987 to October 1988 (Olsson et al 1993). Faecal samples from 279 calves were analysed for the presence of Escherichia coli (K99⁺), rotavirus and Cryptosporidium sp. Twenty (7.2%) of these samples were from diarrhoeic calves. An ELISA was developed and used for the rotavirus analysis. E. coli K99⁺ was detected in 11.5%, Cryptosporidium sp. in 6.1% and rotavirus in 5.4% of the faecal samples. The presence of rotavirus alone and the combination rotavirus and E. coli (K99⁺) was found to be associated with diarrhoea (p<0.001 and p<0.01 respectively).Blood samples from 327 calves were analysed for the level of total protein and γ-globulin. In 43 of these samples (13%) γ-globulin did not separate from the ß₂-region by electrophoresis. The mean total protein concentration was 53.6 g/1 in calves free from diarrhoea. The mean γ-globulin concentration, adjusted to 7 days age was 5.9 g/1. The 20 diarrhoeic calves had lower levels of both total protein and γ-globulin, compared with calves without diarrhoea, but the difference was not significant. One litre more of colostrum at the first feed increased the level of total protein of the calves’ sera by 1.4 g/1 (p = 0.05). Calves born between May and September had a 2.0 g/1 higher (p<0.001) serum concentration of γ-globulin than calves born between October and April.     

Use of field records and competition results in genetic evaluation of station performance tested Swedish Warmblood stallions

The main objective of this study was to investigate possibilities to increase accuracy in the selection and test of Swedish warmblood stallions by combining information from stallion performance tests (SPT) with information from competitions and riding horse quality tests (RHQT). Data on 801 stallions judged at the SPT 1979–2005 were used for the analyses, which also included about 14 900 horses from the RHQT, 26 800 horses with results in show jumping and 14 200 horses with results in dressage competitions.Heritability coefficients were on average 0.41 for individual gaits under rider and 0.36–0.65 for jumping traits in SPT. Heritabilities for competition traits were 0.17 for dressage and 0.27 for show jumping. The heritability for overall conformation in SPT was 0.25. Genetic correlations between stallion performance test traits and competition results were 0.44–0.77 for gaits and dressage, and 0.78–0.96 for jumping traits in SPT and show jumping. The genetic correlation between conformation and results in dressage competitions was 0.22.For stallions participating in SPT in 2004 and 2005 accuracy increased when evaluating stallions by adding information from relatives that have taken part in RHQT and competitions. For show jumping accuracy changed from 0.60 to 0.68 for stallions born in Sweden, an increase with 13%, when information from RHQT and competitions in show jumping were used. For stallions born in a foreign country, the corresponding figure was, 5%, lower. For dressage the information from RHQT and competition results in dressage changed the accuracy from 0.41 to 0.55, an increase with 34%, for stallions born in Sweden. The improvement in accuracy for imported stallions was 11%.     

Influence of soil mineralogy and chemistry on site quality within geological regions in Sweden

The relationship between soil properties and forest site quality was investigated. The site quality functions currently used fail in predicting variations within regions and the purpose of this study was to evaluate if the local accuracy in forest resource assessments could benefit from the use of geological and geochemical data. The investigation was conducted in mid-Sweden within two geological regions. The mineralogy of the parent material (C horizon) was estimated using a method for normative mineralogical assessment and the soil chemistry was determined for five soil horizons. The importance of individual minerals for site quality was different within the two geological regions. Functional relations were established between the properties in different soil horizons and site index. The functions between mineralogy and site index were improved by splitting the data according to the geologically different regions. The mineralogy explained 37–61% of the variation in site index, whereas the properties in the upper soil profile (O–B horizon) related more strongly to site index (18–80%). Stronger relations could be established in the mineralogically rich than in the mineralogically poor area.     

Modelling Impacts of Atmospheric Deposition,Nutrient Cycling and Soil Weathering on the Sustainability of Nine Forest Ecosystems

To assess the impact of acid deposition on the long-term sustainability of nine oak, pine and spruce stands on sandy to loamy sandy parent material in Sweden, Denmark and The Netherlands, a dynamic soil acidification model (ReSAM) was applied. Two deposition scenarios for the period 1990–2090 were used: a business as usual scenario (BAU) and a restrictive critical load scenario (CL). The BAU scenario leads to a strong decrease in both Al concentrations and pH in the topsoil of the Dutch and the Danish sites due to a decrease in the amount of amorphous Al compounds. The decline in pH leads to an enhanced release of base cations by silicate weathering. Despite the ongoing acidification, base saturation increases during the simulation period, due to both the increase in base cation weathering and an increased input from mineralization with the ageing of the tree stands. No change in Al concentration is predicted for northern Sweden as deposition levels are below critical loads. Soil chemistry at the recently replanted Swedish sites is dominated by changes in N cycling instead of by deposition. The CL scenario leads, especially after 2010, to a stronger decline in Al concentration compared with the BAU scenario, which is mainly caused by a reduction of the acid input. Up to 2010, a considerable acid input to the soil system is maintained as N supply is larger than the consumption of N by the trees. Despite the reduction of the deposition of S and N to critical loads, the readily available cation pools are still declining on the Danish and Dutch sites in 2090. It is concluded that deposition levels above critical loads lead to exhaustion of the pool of amorphous Al compounds and a decline in pH. Base saturation does not decline due to an increase in mineralization with stand age and an increase in weathering rate due to the decline in pH.     

Conditions related to solubility of rare and minor elements in forest soils

Soil solutions expelled by high‐speed centrifugation (13900 g) of intact soil sample cores at field moisture from 30 forest topsoils (A horizons of mainly Dystric and Eutric Cambisols, according to the FAO‐Unesco system) low in clay were subjected to analysis of 60 elements, using ICP‐MS and ICP‐AES. Concentrations measured were related to soil and soil solution properties assumed to be important for the solubility of elements, using stepwise regression analysis. On an average two thirds of the variability in soil solution concentration of elements were accounted for by, in particular, organic C concentrations, pH and/or nitrate concentrations of the solutions, varying among elements from 19 to 90 %. Concentrations of elements strongly positively related to soil solution acidity were Al, Be, Ge, Li, Ni, Pb, and Zn, strongly negatively related to acidity were Ca, Mo, and W. Most positively related to nitrate concentrations in soil solutions were B, Ba, Cd, Mg, Mn, and Sr; negatively were Nb, Ta, and Ti. Concentrations of organic C in the soil solutions correlated positively, often quite closely, with most of the other elements studied, including La, all the lanthanides, and with Ag, Br, Cr, Fe, Ga, Hf, Hg, In, P, Th, U, Y, and Zr. Soluble organic compounds were apparently ’︁carriers’ of these elements in the soil solution. The concentrations of elements in HNO₃ digests of the soils usually accounted for just little or no statistical variability of their soil solution concentrations.     

Concentrations of 60 elements in the soil solution as related to the soil acidity

Little is known about solubility and soil solution concentrations of most elements occurring in the solid phase of soils. This study reports changes in solution concentrations of 60 mineral elements following CaCO₃ addition to a moderately acid semi‐natural soil, and possible mechanisms accounting for the differing solubility patterns as related to soil acidity are discussed. Soil solutions were obtained by high‐speed centrifuging and ultrafiltration (0.2 μm) of samples at 60% water‐holding capacity of the A horizon of a Cambisol developed from a shale–gneiss moraine and supplied with CaCO₃ at 20 rates to yield a soil solution pH range of 5.2–7.8. Concentrations of elements were determined in the solutions by ICP‐AES or (for most elements) ICP‐MS. Several distinct patterns of soil solution concentrations as a function of soil solution pH were demonstrated. Positively related to pH and CaCO₃ supply were soil solution concentrations of As, Br, Mo, S, Sb, Se, U, and W, and to a lesser degree, Co, Cr, Hg, Mg, and Sr. Inversely related to pH were concentrations of Al, B, Ba, Bi, Cs, Ce, Eu, Ga, Ge, Fe, Li, K, Rb, Na, Th, and Ti; less distinctly inversely rated were Dy, Er, Gd, Hf, La, Lu, Mn, Nd, Pr, Sm, Sc, Si, Tl, Tm, and Yb. ‘U‐shaped’ relationships to pH were demonstrated for the concentrations of Ag, Cd, Nb, Ni, P, V, and Zr. There were no or irregular relations between pH and concentrations of Be, Cu, Ho, Pb, Ta, and Tb. Differences between elements in their soil solution concentrations as related to total (HNO₃‐digestible) concentrations and the solubility of organic C were also treated. Increasing the pH of a soil by adding CaCO₃ changes the solubility of most mineral elements substantially, the several distinct patterns observed being governed by, for example, ionic properties and charge, affinity for organic compounds, and pH‐dependent formation and solubility of complexes.     

Intestinal macromolecular transmission in underprivileged and unaffected newborn pigs: implication for survival of underprivileged pigs.

Passive immunisation of the newborn pig depends upon intestinal macromolecular transmission to the blood, which ceases within 18 to 36 hours after birth in fed pigs. Macromolecular transmission in newborn, unsuckled pigs was tested by gavage feeding bovine serum albumin and fluorescein isothiocyanate-labelled dextran (molecular weight 70 kDa) together with sow colostrum. Serum levels measured four hours after feeding showed that underweight pigs under 1.0 kg, both apparently normal and weak, had a greater capacity for transmission than did apparently normal pigs over 1.0 kg (unaffected). Weak pigs 1.0 kg, or more, had a transmission equivalent to that of unaffected pigs, indicating that they may be otherwise normal animals affected by birth. Splayleg pigs and their clinically unaffected littermates also showed a greater capacity for transmission than unaffected pigs; splayleg apparently involves the entire litter, although the expression of the syndrome varies. The capacity for transmission in the unaffected pig increased with litter size and decreased with an increase in weight and age after birth. In addition, it was shown that transmission was greater in pigs with higher glucose, insulin and alpha-fetoprotein concentrations and lower haemoglobin, cortisol and alpha 2-macroglobulin f concentrations at birth. It was concluded that immature pigs have a greater capacity for intestinal macromolecular transmission at birth than unaffected pigs over 1.0 kg. Since the capacity for macromolecular transmission decreases with age, the probability of their survival depends very much on the husbandry practices in the herd.     

Surveillance programme for Campylobacter species in Swedish broilers, July 2001 to June 2002

A total of 20,599 samples from 4133 slaughter groups representing about 71 million broilers slaughtered between July 1,2001 and June 30, 2002 were tested for Campylobacter species. From each slaughter group, 40 cloacal samples and 10 samples of neck skin were taken from the carcases on the slaughter line and the samples were pooled, 10 to a pool. Campylobacter species were detected in cloacal samples from 17 per cent of the slaughter groups and in neck skin samples from 22 per cent of the groups, and the monthly prevalence figures ranged from 6 to 32 per cent. In most of the infected groups all four pooled cloacal samples were positive, but 18 per cent of the infected groups had only one or two positive samples. More than 90 per cent of the Campylobacter-positive slaughter groups were delivered by half the producers, and one in four of the producers delivered no Campylobacter-positive slaughter groups.