Identification of a caleosin associated with hazelnut (Corylus avellana L.) oil bodies.

Caleosins are involved in several cellular and biological processes that are closely associated with the synthesis, degradation and stability of oil bodies (OB). Because of the importance and the multiple roles of these OB-associated proteins, in silico identification of sequences corresponding to putative caleosins in the hazelnut genome has been performed, and the association with seed OB was verified using a proteomic approach. Five full-length sequences (CavCLO-H1, CavCLO-H2, CavCLO-H3, CavCLO-L1, CavCLO-L2), belonging to the two groups of caleosins (H and L), have been identified in the hazelnut genome. The number of identified caleosins is in agreement with that previously observed in other plant species, confirming that caleosins comprise small gene families in plants. A proteomic approach allowed us to verify only the presence of CavCLO-H1 in hazelnut OB, suggesting that several members inside this family could have different roles during plant growth and development. In silico analysis also suggests that CavCLO-H1 may act as a peroxygenase.

Yellow mealworm larvae (Tenebrio molitor) inclusion in diets for male broiler chickens: effects on growth performance, gut morphology, and histological findings.

This study evaluated the effects of Tenebrio molitor (TM) larvae meal inclusion in diets for broilers. A total of 160 male broiler chicks (Ross 708) at one-day of age were randomly allotted to four dietary treatments: a control (C) group and three TM groups, in which TM meal was included at 50 (TM5), 100 (TM10), and 150 (TM15) g/kg, respectively. The experimental diets were isonitrogenous and isoenergetic. Each group consisted of five pens as replicates (8 chicks/pen). After the evaluation of growth performance and haematochemical parameters, the animals were slaughtered at 53 days and carcass traits were recorded. Morphometric investigations were performed on duodenum, jejunum, and ileum and histopathological alterations were assessed for liver, spleen, thymus, bursa of Fabricius, kidney, and heart. The live weight (LW) showed a linear (12 and 25 days, P < 0.001 and P < 0.05, maximum with TM15 and TM10) and quadratic (53 days, P < 0.05, maximum with TM5) response to dietary TM meal inclusion. A linear (1 to 12 and 12 to 25 days, P < 0.001, maximum with TM15) and quadratic (12 to 25 days, P = 0.001, maximum with TM15) effect was also observed for the daily feed intake (DFI). The feed conversion ratio (FCR) showed a linear response (25 to 53 and 1 to 53 days, P = 0.001 and P < 0.05, maximum with TM15). Haematological and serum biochemical traits, carcass traits and histopathological findings were not affected by dietary TM meal inclusion (P > 0.05). TM15 birds showed lower villus height (P < 0.05), higher crypt depth (P < 0.05), and lower villus height to crypt depth ratio (P = 0.001) compared with C and TM5. In conclusion, increasing levels of dietary TM meal inclusion in male broiler chickens may improve body weight and feed intake, but negatively affect feed efficiency and intestinal morphology, thus suggesting that low levels may be more suitable. However, no effect on haematochemical parameters, carcass traits, and histological findings were observed in relation to TM meal utilization.

A case of work-related donkey milk allergy

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Feeding a diet contaminated with ochratoxin A for chickens at the maximum level recommended by the EU for poultry feeds (0.1 mg/kg). 1. Effects on growth and slaughter performance, haematological and serum traits.

The European Commission Recommendation 2006/576/EC, suggests that the maximum level of Ochratoxin A (OTA) in poultry feeds should be set at 0.1 mg OTA/kg. Thirty-six one-day-old male Hubburd broiler chickens were divided into two groups, a Control (basal diet) and an Ochratoxin A (basal diet + 0.1 mg OTA/kg) group. The growth and slaughter performance traits were recorded. The liver, spleen, bursa of Fabricius and thymus weights were measured. The erythrocyte and leukocyte numbers were assayed in blood samples, and the heterophils to lymphocytes (H/L) ratio was determined. Alpha-1-acid glycoprotein (AGP), lysozyme, the total protein and the electrophoretic pattern were evaluated in serum samples. Liver enzymes (alanino aminotransferase, ALT and aspartate aminotransferase, AST) and kidney function parameters (uric acid and creatinine) were quantified. The results revealed that feeding a 0.1 mg OTA/kg contaminated diet to chicks caused a decrease in the absolute thymus weight (p < 0.05) and a lower total protein (p < 0.01), albumin (p < 0.01), alpha (p < 0.05), beta (p = 0.001) and gamma (p = 0.001) globulins serum concentration in the Ochratoxin A group. Moreover, the albumin-to-globulin (A/G) ratio of the OTA-treated animals resulted to be higher (p < 0.05). Feeding broiler chickens, a diet contaminated with the maximum level admitted by the European Commission Recommendation (0.1 mg OTA/kg), did not affect the animal performance, slaughter traits, organ weights, haematological parameters, liver enzyme or renal function parameters concentrations but had an overall immunosuppressant effect, with reduction in the thymus weight and of the total serum protein, albumin, alpha, beta and gamma globulins concentration.

Feeding a diet contaminated with ochratoxin A for broiler chickens at the maximum level recommended by the EU for poultry feeds (0.1 mg/kg). 2. Effects on meat quality, oxidative stress, residues and histological traits.

The European Commission Recommendation 2006/576/EC indicates that the maximum tolerable level of ochratoxin A (OTA) in poultry feeds is 0.1 mg OTA/kg. Thirty-six 1-day-old male broiler chicks were divided into two groups, a control (basal diet) and an OTA (basal diet + 0.1 mg OTA/kg) group. The OTA concentration was quantified in serum, liver, kidney, breast and thigh samples. The thiobarbituric acid reactive substances (TBARS) content were evaluated in the liver, kidney, breast and thigh samples. The glutathione (GSH) content, and catalase (CAT) and superoxide dismutase (SOD) activity were measured in the liver and kidney samples. Histopathological traits were evaluated for the spleen, bursa of Fabricius and liver samples. Moreover, the chemical composition of the meat was analysed in breast and thigh samples. In the OTA diet-fed animals, a serum OTA concentration of 1.15 ± 0.35 ng/ml was found, and OTA was also detected in kidney and liver at 3.58 ± 0.85 ng OTA/g f.w. and 1.92 ± 0.21 ng OTA/g f.w., respectively. The TBARS content was higher in the kidney of the ochratoxin A group (1.53 ± 0.18 nmol/mg protein vs. 0.91 ± 0.25 nmol/mg protein). Feeding OTA at 0.1 mg OTA/kg also resulted in degenerative lesions in the spleen, bursa of Fabricius and liver. The maximum tolerable level of 0.1 mg OTA/kg, established for poultry feeds by the EU, represents a safe limit for the final consumer, because no OTA residues were found in breast and thigh meat. Even though no clinical signs were noticed in the birds fed the OTA-contaminated diet, moderate histological lesions were observed in the liver, spleen and bursa of Fabricius.

Clostridia spore formation during aerobic deterioration of maize and sorghum silages as influenced by Lactobacillus buchneri and Lactobacillus plantarum inoculants.

AIMS: The effect of the inoculation of maize and sorghum silages with Lactobacillus plantarum (LP) and Lactobacillus buchneri (LB) on the clostridia spore formation during aerobic deterioration has been studied. METHODS AND RESULTS: The crops were ensiled in 30 l jars, without a lactic acid bacteria inoculant (C), and with an LP or LB inocula (theoretical rate of 1 x 10(6)). After 90 days of conservation, the silages were analysed for the chemical and microbiological characteristics and subjected to an aerobic stability test, during which pH, temperature, nitrate, yeast, mould and clostridia spores were measured. Compared to the C and LP silages, yeasts were reduced in the LB silages, resulting in an increased aerobic stability. Clostridia spores, determined by most probable number (MPN) procedure, increased to 6 log(10) MPN g(-1) in the C and LP maize silages, whereas they reached 3 log(10) MPN g(-1) in C and LP sorghum silages. CONCLUSIONS: Clostridia spore count only slightly increased in the LB maize silages after 342 h (2.59 log(10) MPN g(-1)), whereas it did not show any increase in the LB sorghum silages for the whole period of air exposure. SIGNIFICANCE AND IMPACT OF THE STUDY: The data indicated that clostridia spore outgrowth can take place during silo feedout in aerobic-deteriorated silages and that LB inoculation reduces the risk of clostridia outgrowth after silage opening by increasing the aerobic stability.

A new oxygen barrier film reduces aerobic deterioration in farm-scale corn silage.

Recently, many studies have focused on the aerobic deterioration of corn silage at the farm level, because a large part of the product stored in horizontal silos is exposed to air and is more prone to spoilage. The most important factor influencing the preservation of forage ensiling is the degree of anaerobiosis that is usually achieved with sheets of polyethylene. A new black-on-white (125-microm) coextruded oxygen barrier (OB) film has been developed for silage sealing and was tested in the present experiment to assess the effects on fermentation quality, dry matter losses, and yeast and mold counts at opening of whole-crop corn bunker silos compared with conventional polyethylene (ST) film. Two trials were carried out on 2 commercial farms. The bunkers were divided into 2 parts along the length so that half of the feedout face would be covered with ST film and the other half with OB film. Eight plastic net bags with well-mixed fresh material were weighed and buried in the upper layer of the bunker, and 4 bags were buried in the central part. The silos were opened for summer consumption and were fed out at different rates (19 vs. 33 cm/d). The bags were unloaded, weighed, and subsampled to analyze the DM content, pH, lactic and monocarboxylic acids, ammonia, yeast and mold counts, and aerobic stability. The pH of the peripheral silage was different under the 2 films, with a lower value in the OB treatment. The OB film on farm 1 affected the silage dry matter losses, which were reduced 3.7 times in comparison with the ST film sealing. On farm 2, although the dry matter losses were numerically higher in the silage sealed with the ST film compared with OB film (9.0 vs. 5.9%, respectively), the difference was not statistically significant. However, the corn silage sealed with the ST film was less stable than the silage sealed with the OB film. The results indicate that the new OB film is a promising tool to constrain spoilage and dry matter losses under critical farm conditions, when inadequate amounts of silage are removed daily. The OB film further improved the stability of the corn silage in the peripheral areas of the silos even when a proper harvest-to-feedout management was implemented.

Effect of chestnut tannin on fermentation quality, proteolysis, and protein rumen degradability of alfalfa silage.

Two experiments were conducted on alfalfa to investigate the effects of the addition of commercial chestnut hydrolyzable tannin at ensiling on 1) silage fermentation quality in lab-scale silos and protein degradation in the rumen, and 2) silage fermentation quality and proteolysis in bale silages. Wilted alfalfa was prepared with 4 tannin levels (0, 2, 4, and 6% on a dry matter (DM) basis; T0, T1, T2, T3, respectively) and ensiled in lab-scale silos. Silages (33% DM) were analyzed for fermentation quality, protein rumen degradability in situ, and organic matter digestibility in vitro through gas production after 120 d of conservation. Wilted alfalfa containing 0 and 4% tannin (T0 and T2) was harvested at 40% DM (wilting level I) and 53% DM (wilting level II) for bale (600 mm diameter) silage. Silages were analyzed for fermentation quality after 78 d of conservation. All the silages were well fermented with no butyric acid. Lab-scale silages showed reductions in ammonia, nonprotein nitrogen (NPN) and DM losses in T2 and T3 treatments, while the fermentation acid profiles were unaffected. In experiment 1, the untreated silage (T0) had the highest protein degradability after being incubated in the rumen. The addition of tannin reduced crude protein ruminal disappearance in a dose-dependent manner. However, the tannin reduced the organic matter digestibility by 5.1% for all of the tannin addition levels. The tannin positively affected the silage quality in the round bale silages, in particular reducing ammonia and NPN in the lowest wilting level. In both experiments, T2 treatment reduced proteolysis without any influence of DM on the binding reaction and reduced the NPN by 15% in comparison to the control.

Cytology of Infection of Maize Seedlings by Fusarium moniliforme and Immunolocalization of the Pathogenesis-Related PRms Protein.

ABSTRACT We have investigated the histology of infection of maize seedlings by Fusarium moniliforme in association with a biochemical host defense response, the accumulation of the PRms (pathogenesis-related maize seed) protein. Light microscopy of trypan blue-stained sections and scanning electron microscopy revealed direct penetration by F. moniliforme hyphae through the epidermal cells of the seedling and colonization of the host tissue by inter- and intracellular modes of growth. Pathogen ingress into the infected tissue was associated with the induction of defense-related ultrastructural modifications, as exemplified by the formation of appositions on the outer host cell wall surface, the occlusion of intercellular spaces, and the formation of papillae. Cellular and subcellular immunolocalization studies revealed that PRms accumulated at very high levels in those cells types that represent the first barrier for fungal penetration such as the aleurone layer of germinating seeds and the scutellar epithelial cells of isolated germinating embryos. A highly localized accumulation of PRms within papillae of the inner scutellar parenchyma cells also occurred, suggesting that signaling mechanisms that lead to the accumulation of PRms in papillae of cell types that are distant from the invading pathogen must operate in the infected maize tissues. Our study also revealed the presence of a large number of fungal cells with an abnormal shape that showed PRms-specific labeling. PRms was found to accumulate in clusters over the fungal cell wall. Taken together, the occurrence of PRms in cell types that first establish contact with the pathogen, as well as in papillae, and in association with fungal cell walls suggests that PRms may have a function in the plant defense response.

Cecropin A-derived peptides are potent inhibitors of fungal plant pathogens.

Cecropins are naturally occurring peptides that play an important role in the immune response of insects. Cecropin A-derived and cecropin A-melittin hybrid peptides, all smaller than the natural compound cecropin A, were synthesized and tested for their ability to inhibit growth of several agronomically important fungal pathogens. We found that an 11-amino-acid sequence, corresponding to the N-terminal amphipathic alpha-helix domain of cecropin A, exhibited antifungal activity. Differences in susceptibility of the various pathogens were observed, Phytophthora infestans being particularly sensitive to the shortened cecropin A peptides (IC50 = 2 x 10(-6) M). Biotoxicity of the shortest cecropin A-derived peptide was variously affected by the presence of proteins extracted from leaves of tobacco and tomato plants, either total extracts or intercellular fluids (ICFs). Overall, there was a greater tolerance to tomato protein extracts than to tobacco extracts. These findings suggest that tobacco should not be used as a model for testing the possible protective effects of transgenically expressed, cecropin-based genes. The feasibility of tailoring cecropin A genes to enhance crop protection in particular plant/fungus combinations is discussed.

The maize pathogenesis-related PRms protein localizes to plasmodesmata in maize radicles.

Pathogenesis-related (PR) proteins are plant proteins induced in response to infection by pathogens. In this study, an antibody raised against the maize PRms protein was used to localize the protein in fungal-infected maize radicles. The PRms protein was found to be localized at the contact areas between parenchyma cells of the differentiating protoxylem elements. By using immunoelectron microscopy, we found that these immunoreactive regions correspond to plasmodesmal regions. This was also true for the parenchyma cells filling the central pith of the vascular cylinder, although PRms mRNA accumulation was not detected in these cells. These findings suggest that for one cell type, the parenchyma cells of the central pith, the protein is imported rather than synthesized. The localization of the PRms protein indicates the possible existence of mechanisms for sorting of plant proteins to plasmodesmata and suggests that this protein may have a specialized function in the plant defense response. These findings are discussed with respect to the structure and function of plasmodesmata in cell-to-cell communication processes in higher plants.