Significance of Silver Birch and Bushgrass for Establishment of Microbial Heterotrophic Community in a Metal-Mine Spoil Heap

Differences in the culturable fractions of total and metal-tolerant bacteria inhabiting bulk soil of a metal-mine spoil heap and the rhizosphere of silver birch (Betula pendula) or bushgrass (Calamagrostis epigejos), completed with changes in total microbial community structure in the soil, were assessed by MIDI-FAME (fatty acid methyl ester) profiling of whole-cell fatty acids. In addition, the abundance of metal-tolerant populations among the culturable bacterial communities and their identity and the metal-tolerance patterns were determined. The high proportions of Cu- and Zn-tolerant bacteria that ranged from 60.6% to 94.8% were ascertained in the heap sites. Within 31 bacterial isolates obtained, 24 strains were Gram-positive and Arthrobacter, Bacillus, Rathayibacter, Brochothrix, and Staphylococcus represented those identified. Minimum inhibitory concentration (MIC) data indicated that several strains developed multi-metal tolerance, and the highest tolerance to Cu (10 mM) and Zn (12 mM) was found for Pseudomonas putida TP3 and three isolated strains (BS3, TP12, and SL16), respectively. The analysis of FAME profiles obtained from the culturable bacterial communities showed that Gram-positive bacteria predominated in bulk soil of all heap sites. In contrast, the rhizosphere communities showed a lower proportion of the Gram-positive group, especially for silver birch. For the total microbial community, mostly Gram-negative bacteria (e.g., Pseudomonas) inhabited the heap sites. The results suggest that the quantitative and qualitative development of heterotrophic microbiota in the soil of the metal-mine spoil heap seems to be site-dependent (i.e., rhizosphere vs. bulk soil), according to differences in the site characteristics (e.g., enrichment of nutrients and total metal concentrations) and impact of plant species.     

Antioxidant properties of green tea extract protect reduced fat soft cheese against oxidation induced by light exposure

The effect of two different antioxidants, EDTA and green tea extract (GTE), used individually or in combination, on the light-induced oxidation of reduced fat soft cheeses (0.2 and 6% fat) was investigated. In samples with 0.2% fat, lipid hydroperoxides as primary lipid oxidation products were not detected, but their interference was suggested from the formation of secondary lipid oxidation products such as hexanal and heptanal. The occurrence of these oxidation markers was inhibited by spiking with 50 ppm EDTA or 750 ppm GTE, or a combination of the two prior to irradiation. In contrast, addition of 50 ppm EDTA to samples with 6% fat was ineffective, but 750 ppm GTE (alone or in combination with EDTA) strongly reduced levels of hexanal and heptanal. Accumulation of primary lipid hydroperoxides was not affected by GTE, hence antioxidative activity was ascribed to scavenging of hexanal and heptanal precursors. These radical intermediates result from hydroperoxide disintegration, and subsequent scavenging by GTE, which acts as a radical sink, corroborates the intense signal observed by electron paramagnetic resonance (EPR) spectroscopy.     

Pharmacokinetics of penicillin-G in ewes and cows in late pregnancy and in early lactation

Concentrations of penicillin-G in serum were determined after single intravenous doses of potassium penicillin-G (10 mg/kg body wt) to ewes and cows in late pregnancy and in early lactation. Penicillin-G in serum was analysed by a microbiological method and pharmacokinetic parameters were calculated by model-independent methods. Serum concentrations were lower in early lactation than in late pregnancy in both ewes and cows. The differences were statistically significant at most sampling times in ewes but only during the first hour in cows.
Weight corrected values of clearance and volume of distribution were significantly higher in early lactation than in late pregnancy in both ewes and cows. Mean residence time and elimination-half life were shorter in lactating than in pregnant ewes, however for the latter parameter the difference was not statistically significant. Neither of these parameters changed in cows.
It is concluded that in both ewes and cows pharmacokinetic parameters of penicillin-G are altered from late pregnancy to early lactation but that these changes have little practical impact and do not call for a revised dosage regime of the studied drug.     

Porcine nephropathy induced by long-term ingestion of ochratoxin A.

Nine pigs were fed crystalline ochratoxin A in their feed at a concentration of about 1 mg/kg. Three pigs and their controls were killed after 3 months and 6 pigs and controls were killed after 2 years. A decrease of the ratio TmPAH/CIn, increased urinary glucose excretion and decreased ability to concentrate urine, occurred within a few weeks and aggravated slightly during the 2-year period. Changes in renal structure, characterized by degeneration and atrophy of proximal tubules, interstitial fibrosis and hyalinization of glomeruli, were progressive during time of exposure, but terminal renal failure was not reached. The kidney, liver, muscular and adipose tissue contained 3 to 27 microgram ochratoxin A/kg after 3 months of exposure. No further accumulation of ochratoxin A residue was found after 2 years of exposure.     

急性感染肝片吸虫水牛血细胞免疫反应的研究

 研究了水牛急性感染肝片吸虫后血细胞免疫反应在抗感染中的作用机制：结果表明．水牛感染后．ＷＢＣ的总体水平在整个感染期高于对照组；ＤＣ中的嗜酸性粒细胞（％）在第 ２周即显著高于对照组直到 １９周．以后下降并接近对照组；嗜中性粒细胞（％）在第５～１６周低于或明显低于对照组．以后两组接近；淋巴细胞（％）在感染后的第２～５周低于或明显低于对照组．以后接近．至第１４周又低于或明显低于对照组直至２１周；单核细胞和嗜碱性粒细胞（％）在整个实验期无显著差异；Ｔ－淋巴细胞（％）从第１周起显著下降，Ｂ－淋巴细胞（％）显著升高．１１周后均与对照组无明显差异；ＲＢＣ－ＣＲ１花环率在２～１６周显著低于对照组．以后逐渐恢复接近对照组，而ＲＢＣ－ＩＣ花环率在２～１８周高于或明显高于对照组。提示水牛在急性感染肝片吸虫后，血细胞的特异性和非特异性免疫反应变化剧烈，共同参与抗肝片吸虫感染机制。     

Short-term effects on productivity and egg quality in nutrient-restricted versus non-restricted organic layers with access to different forage crops

Abstract

Two experiments were conducted to study the effects of different forage crops on productivity and some egg quality parameters of small flocks of organic laying hens fed whole wheat or concentrates. Each experiment was carried out in a split plot design with two different forage crops and two types of supplementary feed (typical concentrate for organic layers versus whole wheat) with three replications. In the first experiment the tested forage crops were of a well-established grass/clover and a mixture of forbs (Fagopyrum esculentum, Phacelia tanacetifolia and Linum usitatissimum). In the second experiment the tested forage crops were a well-established grass/clover and chicory (Cichorium intybus cv. Grassland Puna). The results on productivity and egg quality suggest that laying hens consume large amounts of foraging material when accessible. In nutrient restricted hens (wheat-fed) the forage may yield a substantial contribution to the requirements of amino acids and metabolizable energy although productivity parameters and measurements on dry matter in albumen showed that wheat-fed hens, on a short-term basis, were not able to fully compensate for the lack of protein and amino acids by increased foraging. Of the forage crops investigated especially chicory seems to contribute to the nutrition of the hens. Measurements on eggshell parameters showed that oyster shells together with foraging material were sufficient to meet the hens’ calcium requirements. Yolk colour clearly revealed that laying hens consume large quantities of green fodder irrespective of the type of supplementary feed. Yolk colour from hens with access to chicory tended to be darker, of a redder and less yellow hue compared with grass/clover fed hens, which is considered a positive quality.     

Effects of breed and dietary nutrient density on the growth performance,blood metabolite,and genes expression of target of rapamycin (TOR) signalling pathway of female broiler chickens

This study was conducted to compare the effects of exchanged diets with identical energy level on characteristics of slow‐growing (WENs Yellow‐Feathered Chicken, WYFC) and fast‐growing (White Recessive Rock Chicken, WRRC) female chickens. A total of 1450 WYFC and 1150 WRRC 1‐day‐old female hatchlings were used. A high‐nutrient‐density (HND) diet and a low‐nutrient‐density (LND) diet were formulated for three phases. A completely randomized experimental design with a 2 × 2 factorial arrangement (diet and breed), each with five replicates of 145 and 115 birds, was applied. The results showed that WRRC had a higher body weight (BW), average daily feed intake and average daily gain than WYFC throughout the experiment (p < 0.05). WYFC that were provided with HND groups had a higher BW only in the starter and grower phases, whereas WRRC had a higher BW in the HND group than in LND groups throughout the experiment. The feed:gain ratio and protein efficiency ratio (PER) were better for WRRC in the starter and grower phases; however, these ratios were better for WYFC in the finisher period. The LND groups had a higher PER throughout the experiment for both breeds (p < 0.05). The breast and leg muscle weights were higher for WRRC compared with WYFC during the grower and finisher phases (p < 0.05). WRRC had a lower liver index but higher serum UA and alkaline phosphatase (ALP) concentrations than WYFC (p < 0.05). No diet effect was observed on organ indices, muscle yields or blood responses. The gene expressions of Rheb, TOR, S6K1 and 4E‐BP1 in gastrocnemius muscle were the highest in the WYFC‐LND groups at 63 and 105 days (p < 0.05). These findings suggested that different genotypes respond differently to changes in dietary nutrient density and that lower‐nutrient‐density diets are optimal for the long‐term housing of broiler chickens.     

Protein and mRNA expression of follicle‐stimulating hormone receptor and luteinizing hormone receptor during the oestrus in the yak (Bos grunniens)

Follicle‐stimulating hormone (FSH) and luteinizing hormone (LH) have a central role in follicle growth, maturation and oestrus, but no clear pathway in the seasonal oestrus of yak (Bos grunniens) has been found. To better understand the role of FSH and LH in seasonal oestrus in the yak, six yaks were slaughtered while in oestrus, and the pineal gland, hypothalamus, pituitary gland, and gonads were collected. Using real‐time PCR and immunohistochemical assays, we determined the mRNA and protein expression of the FSH and LH receptors (FSHR and LHR) in these organs. The analysis showed that the FSHR mRNA expression level was higher in the pituitary gland tissue compared with LHR (p < .01) during oestrus. By contrast, there was low expression of FSHR and LHR mRNA in the pineal gland and hypothalamus. FSHR mRNA expression was higher than that of LHR (p < .05) in the ovary, whereas LHR mRNA expression was higher than that of FSHR (p < .01) in the uterus. FSHR and LHR proteins were located in the pinealocyte, synaptic ribbon and synaptic spherules of the pineal gland and that FSH and LH interact via nerve fibres. In the hypothalamus, FSHR and LHR proteins were located in the magnocellular neurons and parvocellular neurons. FSHR and LHR proteins were localized in acidophilic cells and basophilic cells in the pituitary gland, and in surface epithelium, stromal cell and gland epithelium in the uterus. In the ovary, FSHR and LHR protein were present in the ovarian follicle. Thus, we concluded that FSHR and LHR are located in the pineal gland, hypothalamus, pituitary and gonad during oestrus in the yak. However, FSHR was mainly expressed in the pituitary gland and ovaries, whereas LHR was mainly expressed in the pituitary gland and uterus.     

Continuous monitoring of body temperature in pigs using non-invasive ear canal sensors

Monitoring of the body temperature in animals kept under intensive production conditions is desirable for a number of reasons: oestrus detection, disease monitoring and stress indication in addition to more specific needs, such as the selection of breeding pigs resistant to malignant hyperthermia and for various research purposes.     

Purification of the toxin protein PC from Arthrinium phaeospermum and its effect on the defence enzymes of Bambusa pervariabilis × Dendrocalamopsis grandis varieties

Bamboo blight in hybrid Bambusa pervariabilis × Dendrocalamopsis grandis is caused by the fungus Arthrinium phaeospermum. One component designated as P_C with pathogenic activity and a molecular weight of about 27 kDa was obtained from this fungus by ammonium sulphate precipitation, polyethylene glycol concentration, Sephadex G‐100 gel chromatography and Q‐Sepharose Fast Flow anion exchange resin. The toxin P_C was shown to cause the same typical symptoms caused by the pathogen itself, although the reaction of the toxin was quicker than the pathogen in all four hybrid bamboo varieties. A threshold toxic dose of 10–20 μg/ml was observed for two resistant varieties, while only 5–10 μg/ml was observed for two susceptible varieties. Moreover, effects of the purified toxic protein on the activities of superoxide dismutase, peroxidase, phenylalanine amonnialyase, polyphenol oxidase, chitinase and β‐1,3 glucanase in the different bamboo varieties were analysed using the impregnation and leaf disc methods. The results showed a positive correlation between the resistance of bamboo and the activities of all six enzymes. The activities of all enzymes except β‐1,3 glucanase decreased over the time course of investigation. These results proved the important role played by toxic proteins in the pathogenicity of A. phaeospermum and their potential for selecting resistant varieties or identify the resistance of this bamboo.