Effects of 6-hydroxydopamine on the development of the immune system in chickens

It has been suggested that the sympathetic nervous system communicates with lymphocytes expressing cell surface receptors for neurotransmitters such as norepinephrine (NE), on the basis of the finding that neurotransmitters modify immune responses in mammalian species. We confirmed that chicken lymphocytes in the brusa of Fabricius, thymus and spleen expressed beta-adrenergic receptor (beta-AR) mRNA from embryonic day (E) 10 and that intracellular cAMP level was elevated by NE, suggesting that lymphocytes express functional beta-AR on their surface at an early embryonal stage. To clarify whether the nervous system is involved in the development of the immune system, the effects of 6-hydroxydopamine (6-OHDA), one of sympathectomizing agents, on chicken lymphocytes was investigated. A single injection of 6-OHDA at a dose of 400 microg into a chicken embryo was carried out at E7 or 14 (as referred to E7 group and E14 group, respectively). NE level and the relative proportion of Bu-1a(+), CD4(+) and CD8(+) cells in the spleen of 3-week-old chickens were not altered by 6-OHDA treatment. However, the proliferative responses and expression of IL-2 mRNA in spleen cells cultured with pokeweed mitogen were reduced in E7 group compared with those of control. Furthermore, in CD8(+) spleen cells of E14 group of 3-week-old chickens, the expression of beta-AR mRNA and the relative increase of intracellular cAMP stimulated with NE were significantly decreased. These results suggest that the sympathetic nervous system affects the development of the immune system.     

Clinical characteristics and persistence of bovine mastitis caused by different species of coagulase-negative staphylococci identified with API or AFLP

The coagulase-negative staphylococcal species causing mastitis in lactating cattle were identified and possible differences in the clinical characteristics or persistence of mastitis caused by different CNS were evaluated. The effect of antimicrobial treatment was also assessed. In addition, AFLP-typing of CNS was compared with the phenotypic identification. A total of 133 clinical or subclinical quarter cases of intramammary infection caused by CNS from the practice area of the Ambulatory Clinic of the University of Helsinki were studied. Bacteriological diagnosis was based on biochemical (API) testing. Staphylococcus simulans (43.6%) followed by S. chromogenes (23.3%) were the most common CNS species isolated from the milk samples. Ninety-nine isolates were genotyped using AFLP-analysis. Only 75.0% of S. chromogenes and S. simulans isolates identified with API test were clustered with the type strains of these species. Approximately half of the mastitis cases were clinical, and in the majority clinical signs were mild. The severity and persistence of intramammary infection were unaffected by CNS species. Fifty-nine percent of the quarter cases were treated with antimicrobials, and the rest were left without treatment. Mastitis due to beta-lactamase-negative CNS was treated with penicillin G and that due to beta-lactamase-positive CNS with cloxacillin. Nineteen percent of the isolates were beta-lactamase-positive. The bacterial cure rate for quarters treated with antimicrobials was high, 85.9%, as opposed to only 45.5% for untreated quarters. Bacterial cure rates for the most common CNS species or AFLP clusters were not statistically different. Further studies on identification of CNS species are needed.     

Use of amaranth,quinoa and kañiwa in extruded corn-based snacks

Amaranth (Amaranthus caudatus), quinoa (Chenopodium quinoa) and kañiwa (Chenopodium pallidicaule) are pseudocereals regarded as good gluten-free sources of protein and fiber. A co-rotating twin screw extruder was used to obtain corn-based extrudates containing amaranth/quinoa/kañiwa (20% of solids). Box–Behnken experimental design with three independent variables was used: water content of mass (WCM, 15–19%), screw speed (SS, 200–500 rpm) and temperature of the die (TEM, 150–170 °C). Milled and whole samples were stored in open headspace vials at 11 and 76% relative humidity (RH) for a week before being sealed and stored for 9 weeks in the dark. Hexanal content was determined by using headspace gas chromatography. Extrudates containing amaranth presented the highest sectional expansion index (SEI) (p < 0.01) while pure corn extrudates (control) presented the lowest SEI and greatest hardness (p < 0.01). SEI increased with increasing SS and decreasing WCM. In storage, whole extrudates exposed to 76% RH presented the lowest formation of hexanal. This study proved that it was possible to increase SEI by adding amaranth, quinoa and kañiwa to pure corn flour. The evaluation of lipid oxidation suggested a remarkable stability of whole extrudates after exposure to high RH.     

Effects of bromides of potassium and ammonium on some crops

In this work, the response of wheat (Triticum aestivum L.), rye (Secale cereale L.), oat (Avena sativa L.), and pea (Pisum sativum L.) to bromides of potassium (KBr) and ammonium (NH₄Br) was studied. All plants were capable of accumulating high concentrations of bromine (Br). However, the Br accumulation depended on the Br compounds presented in the growth medium and plant species. The highest Br concentrations were observed in leaves and roots of the seedlings germinated in the medium spiked with KBr. Oat accumulated more Br than other plants and the lowest Br accumulation was observed in pea. The bioaccumulation of Br resulted in suppression of plant biomass and concentrations of several essential nutrients (K, Na, Ca, Mg, Zn and Cl). The most negative effects were caused by NH₄Br. Probably, this action was due to cumulative effects of Br^- and NH₄⁺. Among other plant species, the most tolerant to bromides was oat and the most sensitive was wheat.     

Motives and Incentives for Joining Forest Owner Associations in Estonia

The development of private ownership is an important outcome of structural changes for the whole economy as well as for the forestry sector in Estonia. Cooperation between forest owners has been seen as one possibility for increasing the provision of various forest-related benefits and goods. Yet the extent of cooperation between forest owners is still not at a sufficient level, but the reasons have not been extensively studied. The authors’ aim was to find out the key determinants for forest owners to join a forest owner association and to explore how cooperation between owners could be increased. Survey data were used to divide the respondents into two groups according to whether they were members of forest owners associations or not. It was found that one key aspect is the size of the forest property—association members usually manage larger forest areas than non-members. In addition, the members tend to be more active and consistent in forest management activities than non-members. Also there is potential towards cooperation within non-members as their plans for the future are much more targeted. Although there are limits to voluntary cooperation, a huge potential for Estonian private forest owners could be realised by diversifying forest owner association activities and services to meet the different expectations of forest owners.     

Effects of planting orientation and density of willows on biomass production and nutrient leaching

Willow buffer strips are a promising vegetated filter for the reduction of non-point source pollution from agricultural land to watercourses resulting from the rapid growth of shoots and from the large amount and distribution of roots. A greenhouse experiment tested the hypothesis that a new planting method, planting cuttings horizontally, exhibited more biomass production and more effective filter than did planting cuttings vertically. Due to the different times taken for shoots break through the soil surface, the summed height of all shoots of horizontally planted cuttings was significantly smaller than that of the vertical ones at the beginning of the growth period. The difference in the height of all of the shoots between planting orientations decreased with time. After 16 weeks growth, the biomass of the stem, leaves and fine roots was not affected by the planting orientation. The coarse root biomass was larger in the horizontal treatments and decreased with increased density. The total biomass, as well as the biomass of stem or leaves, of each treatment, increased with increased planting density. The individual plant biomass, as well as that of the stem or leaves, decreased with increased planting density. Compared with the unplanted control treatment, the planted treatments significantly reduced the total-N, NO₃-N, PO₄-P and SO₄-S leaching. The planting orientation did not affect the nitrate leaching. The horizontally planted cuttings were slightly more effective for reducing the SO₄-S leaching and the vertically planted cuttings were slightly more effective for reducing the PO₄-P leaching. Lower PO₄-P leaching was observed only with higher planting density. With regard to the horizontal planting method, further studies are needed to explore the influence of different willow clones, the size of cuttings, pre-planting treatments, planting geometry (configuration) and soil conditions on survival, the number of shoots produced, the biomass production and the amount and distribution of roots.     

Innate immune response in experimentally induced bovine intramammary infection with Staphylococcus simulans and S. epidermidis

ABSTRACT: Coagulase-negative staphylococci (CNS) are in several countries the most common bacteria isolated in subclinical mastitis. To investigate the innate immune response of cows to infections with two common mastitis-causing CNS species, Staphylococcus epidermidis and Staphylococcus simulans, experimental intramammary infection was induced in eight cows using a crossover design. The milk somatic cell count (SCC), N-acetyl-β-D-glucosaminidase (NAGase) activity, milk amyloid A (MAA), serum amyloid A (SAA) and proinflammatory cytokines interleukin (IL)-1β, IL-8, and tumor necrosis factor α (TNF-α) were determined at several time points before and after challenge. All cows became infected and showed mild to moderate clinical signs of mastitis. The spontaneous elimination rate of the 16 infections was 31.3%, with no difference between species. Infections triggered a local cytokine response in the experimental udder quarters, but cytokines were not detected in the uninfected control quarters or in systemic circulation. The innate local immune response for S. simulans was slightly stronger, with significantly higher concentrations of IL-1β and IL-8. The IL-8 response could be divided into early, delayed, or combined types of response. The CNS species or persistency of infection was not associated with the type of IL-8 response. No significant differences were seen between spontaneously eliminated or persistent infections.     

Effects of soil amendments on antimony uptake by wheat

Purpose

Environmental chemistry of antimony (Sb) is still largely unknown. Many questions remain about its availability to plants and effects of fertilizers on mobility of Sb in the rhizosphere soil. In this work, we focused on the following problems: (1) uptake of Sb by wheat seedlings grown in soil enriched with this metalloid and (2) impact of soil amendments on the plant growth, Sb uptake from soil, and its transfer from roots to upper plant parts.

Materials and methods

To obtain further information on the possible transfer of Sb into plants, greenhouse pot experiments were carried out. Soil was spiked with 15 mg kg^?1 of Sb and amended with either chicken manure or natural growth stimulator Energen. Wheat Triticum aestivum L. seedlings were grown in the soil during 17 days. Plants together with rhizosphere soil were collected several times in the course of the experiment. The ICP-OES and ICP-MS techniques were applied to determine the concentrations of macro- and trace elements in the plant and soil material.

Results and discussion

Growth of wheat seedlings in Sb-spiked soil resulted in Sb accumulation in roots and leaves of the plants. Energen and especially chicken manure were capable of stimulating transfer of Sb to more mobile and, as a consequence, more available to the plants form, thus enhancing both uptake of Sb from soil and its transfer from roots to upper plant parts. The accumulation of Sb by plants led to a decrease of Sb concentration in the rhizosphere soil with time, and the most significant decrease was observed after amendment of soil with fertilizers.

Conclusions

Fertilizers may be used to increase phytoextraction of Sb and its removal from contaminated soils. However, such an amendment of soil should be done with caution in order to exclude or at least reduce the negative effects on plants.     

Influence of Protein Level and Supplementary L-Methionine and Lysine on Growth Performance and Fur Quality of Blue Fox ( Alopex lagopus )

The influence of dietary protein content and composition on growing-furring blue fox ( Alopex lagopus ) was studied with three protein levels [15%, 22.5% and 30% of metabolizable energy (ME) from protein]. The two lowest diets were fed as such, or as supplemented with L-methionine or lysine. Growth, from the start of the experiment in July to mid-September, improved with increasing protein level ( P < 0.01). Lysine supplementation, unlike methionine, decreased early growth ( P <0.05). During the last months of the experimental period, differences in weight gain between the groups evened out. Skin length and quality declined with decreasing protein level ( P <0.05). Methionine and lysine had opposite effects on skin length ( P <0.10). For normal body growth and skin length, a level of 0.40 g of digestible L-methionine MJ -1 ME, and 25-32% protein in feed dry matter, was required. When feed ingredients are deficient in methionine, a supplementation is recommended. Methionine is the first limiting amino acid of the two amino acids studied here.