Fresh-stem bending of silver fir and Norway spruce

The bending and growth characteristics of large fresh stems from four silver fir (Abies alba Mill.) and three Norway spruce (Picea abies (L.) Karst.) trees were studied. Twenty logs taken from different stem heights were subjected to four-point bending tests. From the bending test records, we calculated stress-strain curves, which accounted for detailed log taper, shear deformation and self weight. From these curves we determined, among other parameters, the modulus of elasticity (MOE), the modulus of rupture (MOR) and the work absorbed in bending (W). No significant differences were found between species for the wood properties examined. Values of MOE, MOR and W generally decreased with stem height, with MOR in the range of 43 to 59 MPa and MOE ranging from 10.6 to 15.6 GPa. These MOE values are twice or more those reported for stems of young Sitka spruce (Picea sitchensis (Bong.) Carr.) trees. Based on the radial growth properties measured in discs from the logs, we calculated predicted values of MOE and MOR for the stem cross section. The predictions of MOE were precise, whereas those of MOR were approximate because of a complex combination of different failure mechanisms. Methods to test and calculate MOE, MOR and W for the stems of living trees are discussed with the aim of improving analyses of tree biomechanics and assessments of forest stability protection.     

The antihistaminic chlorpheniramine inhibitsin vitro growth of several fungi isolated from harvested fruits

Chlorpheniramine (CPA) is an antihistaminic that changes the conformation of DNA and inhibits polyamine biosynthesis in mammalian cells. In the present work, we tested the effect of CPA on four genera of fungi species (Altemaria alternata, Botrytis cinerea, Cladosporium cladosporioides and threePenicillium spp.) grownin vitro. Similar growth inhibitions of these genera were produced by 0.5 raM iprodione, CPA and histidinol, but CPA was the most effective. The CPA sensitivities of the twoB. cinerea strains were different. Putrescine did not restore the fungal growth inhibited by CPA.     

Characterization of Fusarium mangiferae isolates from mango malformation disease in Southern Spain

During the last years, Fusarium strains have been isolated from shoots and inflorescences of mango trees affected with floral and vegetative malformation in different orchards from the Axarquía region (south of Spain), highlighting the identification of Fusarium mangiferae. With the aim of elucidate epidemiological aspects and design more efficient control strategies, population diversity among the strains of F. mangiferae associated with MMD in Spain was determined by ap-PCR, RAPD-PCR, vegetative compatibility groups (VCGs) and mating type analyses. Three different VCGs were found among the Fusarium mangiferae Spanish isolates, two of them showing similar ap–PCR and RAPD profiles. PCR with primers specific for the mating type (MAT) alleles resulted in amplification of the MAT-2 allele fragment among the majority of the isolates, there being only two isolates MAT-1. This population diversity suggests at least three possible independent introductions of the pathogen into the Axarquía region.     

Diagnosis of anatoxin-a poisoning in dogs from North America.

Anatoxin-a, a toxin produced by several genera of blue-green algae, is considered a potent neurotoxin. Ingestion of water contaminated with the toxin results in acute neurological signs and often death. This report describes fatal cases of anatoxin-a ingestion in 6 dogs, with confirmation of anatoxin-a exposure by liquid chromatography/tandem mass spectrometry (LC-MS/MS/MS). In 1 outbreak, 3 dogs developed seizures and died within an hour after swimming in a river in California, while the other outbreak involved 3 dogs that died within 1 hour after swimming in a pond in Ontario. Anatoxin-a poisoning is rarely reported in dogs as a cause of acute neurological signs and death. However, increased occurrences of blue-green algae blooms in North America make this neurotoxin an important consideration in the diagnosis of sudden death associated with environmental water exposure. This brief communication reports on the isolation and detection of anatoxin-a from environmental water sources and the stomach contents of North American dogs dying of acute neurotoxicosis. This demonstrates the first documented cases of anatoxin-a poisoning in dogs in North America and the importance of LC-MS/MS/MS in identifying neurotoxins responsible for sudden death in cases of suspected blue-green algae toxicosis; especially those cases showing no gross or histological lesions.     

Electronic feed stations for feeding concentrates to pregnant ewes on commercial sheep farms

ABSTRACT

The aim of this study was to investigate the use and capacity of electronic feed stations (EFS) on commercial sheep farms. The study was conducted on four commercial farms and the numbers of pregnant ewes per EFS were 36, 70, 72 and 80, respectively. Each farm was visited once and behavioural observations were carried out. In addition the date and time for both entering and leaving the EFS and the amount of concentrates dispensed at each visit for extracted. The vast majority of the ewes used the EFS regularly. The number of rewarded visits per ewe per day varied from 3.2 to 5.9, whereas the number of unrewarded visits ranged from 6.0 to 21.5 per ewe per day. We conclude that feeding concentrates to groups of pregnant ewes in EFS function satisfactory, but the design of the entrance and exit gate still have to be improved considerably.     

Sensory quality and chemical composition in carrots: A multivariate study

Carrots from designed trials and organic and conventional farms were analysed for sensory quality and chemical composition. The data were combined in principal component analyses and partial least squares regression for exploration of the main factors responsible for the variation in quality. One of the most important factors was fertilization. Carrots grown with no fertilizer and carrots fertilized with 40–80 kg nitrogen ha^?1 as mineral fertilizer or 20–72 tons ha^?1of organic fertilizer contained more total sugars and total flavour strength, less crispness, crude protein, true protein and carotene, and had a lower pH, compared with carrots fertilized with 100–192 kg nitrogen ha^?1 as mineral fertilizer. Location site was also very important in the explanation of the total variation and was a composite factor of precipitation, temperature in June, growth system and length of growth period. Soil type, amount of organic fertilizer, use of pesticides and temperatures in July and August seemed to be of less importance.     

A brief review of the past, present and future of wood preservation

Wood products used in exterior applications must be protected against biodeterioration by decay fungi, insects such as termites, and other organisms. Traditionally, wood products for residential or industrial applications have been protected by treatment with chromated copper arsenate (CCA) or older inexpensive organic biocides, but environmental and disposal concerns and governmental regulations have resulted in a rapid and dramatic worldwide shift to copper-based systems. The current development trend is towards employing totally organic biocides based on relatively benign and expensive agrochemicals, with continuing research directed towards developing non-biocidal methods to protect wood.     

Occurrence and distribution of resistance to QoI fungicides in populations of Podosphaera fusca in south central Spain

Cucurbit powdery mildew caused by Podosphaera fusca limits crop production in Spain. Since its management is strongly dependent on chemicals, the rational design of control programmes requires a good understanding of the fungicide resistance phenomenon in field populations. Fifty single-spore isolates of P. fusca were tested for sensitivity to three quinone-outside inhibiting (QoI) fungicides: azoxystrobin, kresoxim-methyl and trifloxystrobin. Minimum inhibitory concentration (MIC) values for QoI-sensitive isolates were found to range from 0.25 to 10 μg ml⁻¹ for azoxystrobin to 5–25 μg ml⁻¹ for kresoxim-methyl, using a leaf disc-based bioassay. High levels of cross-resistance to QoI fungicides were found. Eleven isolates showed resistance to the three QoI fungicides tested with MIC and EC₅₀ values >500 μg ml⁻¹ resulting in RF values as high as >715 and >1000 for trifloxystrobin and azoxystrobin, respectively. A survey of P. fusca QoI resistance was carried out in different provinces located in the south central area of Spain during the cucurbit growing seasons in 2002, 2003 and 2004. Examination of a collection of 250 isolates for QoI resistance revealed that 32% were resistant to the three fungicides tested; the provinces of Ciudad Real, Córdoba and Murcia being the locations with the highest frequencies of resistance (44–74%). By contrast, no resistance was found in Badajoz, and relatively low frequencies were observed in Almería and Valencia (10–13%). Nearly 50% of resistant isolates were collected from melon plants. Based on these data, recommendations about the use of QoI fungicides for cucurbit powdery mildew management in the sampled areas are made.     

Correlated response to selection for litter size in pigs: II. Carcass,meat, and fat quality traits

Data on a pig line selected for litter size (H) and a control line (C) were used to estimate the correlated responses to litter size in carcass, meat, and fat quality traits. The differences between the genetic means of animals from line H and line C were used to estimate correlated responses. No differences were found between the two lines in carcass measurements except backfat depth, which was higher (P < 0.05) in line H (0.69 +/- 0.28 mm). This led to a decrease (P < 0.05) in predicted carcass lean content (-6.0 +/- 2.7 g/kg). Differences in joint weight distribution between lines were primarily due to belly weight, which was higher (P < 0.05) in line H (6.3 +/- 1.2 g/kg). There were no important changes in meat quality traits. Chemical composition of semimembranosus muscle (SM) and subcutaneous backfat (SB) differed between lines only for DM in SB, which was higher (P < 0.05) in line H (15.1 +/- 7.1 mg/g), and for the fatty acid composition of intramuscular fat. The fatty acid profile in line H showed a lower (P < 0.01) proportion of polyunsaturated fatty acids (-14.7 +/- 4.8 mg/g FA), particularly with regard to the content of linoleic acid (-12.5 +/- 3.9 mg/g FA). It is concluded that selection for litter size reduced the lean content in the carcass but the proportion of high-priced cuts and meat quality traits were not affected. However, selection may lead to changes in the composition of intramuscular fat lipids towards a lower content of polyunsaturated fatty acids. The observed correlated effects can be interpreted assuming that selected pigs are more mature at the same weight, though the underlying genetic and physiologic processes that cause them are unknown. The results of this experiment indicate that the metabolic pathways taking part in fat metabolism should be considered first.