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291.
The effect of dietary supplementation with N,N‐dimethylglycine sodium salt (Na‐DMG) was evaluated in a feeding trial with 1500 1‐day‐old broiler chicks (Cobb 500). DMG was supplemented at 0, 0.1, 0.2, 0.5 or 1 g Na‐DMG/kg feed to a ration with either animal fat (chicken fat) or vegetal fat (soy oil) as main fat source. In the vegetal fat diets, production value was significantly linearly improved by supplementation with DMG up to 11%. Irrespective of dietary fat source, abdominal fat percentage was significantly linearly reduced up to 24% and meat yield tended to increase linearly with DMG level up to 4%. In the vegetal fat groups, DMG significantly lowered abdominal fat pad by up to 38% and tended to increase meat yield up to 6% at the highest dose. Fasted non‐esterified fatty acid level significantly decreased with increasing DMG level up to 36% and thiobarbituric acid reactive species (TBARS) decreased with a statistical trend up to 46% at the highest dose. In vegetal fat diets, addition of DMG resulted in significant lower TBARS level by 56% at the highest dose. Finally, a significant quadratic effect on ascites heart index was present in the vegetal fat diets, with a minimal value at 0.5 g Na‐DMG/kg. In conclusion, dietary supplementation with DMG may improve technical and slaughter performance, and may reduce oxidative stress and pulmonary hypertension, but the degree of effects is modulated by fatty acid profile of the diet. Herewith, effects are more pronounced in a diet rich in polyunsaturated fatty acids compared with a diet rich in saturated and monounsaturated fatty acids.  相似文献   
292.
Thirty-five samples of cow feces (cowpat and cow manure) and pig slurries subjected to different treatment processes and different storage times before land spreading were extracted and analyzed by gas chromatography-mass spectrometry to determine their fecal stanol profiles. The fresh pig slurry data presented here increase considerably the classical range of values obtained for steroid ratios, resulting in an overlap with the range for cow feces. These results lead to the inability to distinguish species source of feces on the basis of steroid ratios alone. The cause of these differences is not known, although it appears likely to be related to differences in the metabolism of animals in relation to their age and/or variations in diet, rather than to secondary mechanisms of steroid degradation during storage or/and treatment of the feces. Nevertheless, the specificity of steroids to serve as a tool to differentiate cow feces from pig slurries is restored by considering the fecal stanol profile, notably, the six most diagnostic stanol compounds, which are 5β-cholestan-3β-ol (coprostanol), 5β-cholestan-3α-ol (epicoprostanol), 24-methyl-5α-cholestan-3β-ol (campestanol), 24-ethyl-5α-cholestan-3β-ol (sitostanol), 24-ethyl-5β-cholestan-3β-ol (24-ethylcoprostanol), and 24-ethyl-5β-cholestan-3α-ol (24-ethylepicoprostanol). In this study, chemometric analysis of the fingerprint of these six stanols using principal components analysis (PCA) distinguished pig slurries from cow feces. The application of PCA to the stanol profiles, as developed in this study, could be a promising tool for identifying the animal source in fecal contamination of waters.  相似文献   
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The domestication of indigenous fruits through agroforestry is seen as one of the important issues in the transformation in the way in which land is used within rural areas. A study of the variation in fruit traits is also important as it is a prerequisite for cultivar development in the domestication process. Following an aridity gradient, phenotypic variation was assessed in fruits of Sclerocarya birrea subsp. birrea, native to West African semi-arid areas. Fruits were collected from 42 trees of various diameters in agroforestry parklands from the dry and semi-humid Sudanian zones. They were partitioned into peel, flesh and pit. Each fruit was labelled and its components were measured and weighted. The overall mean fruit mass was 18.58 ± 0.24 g (mean ± SE) but fruits from the population in the drier zone were significantly larger (19.90 ± 0.37 g vs 17.02 ± 0.24 g; P < 0.001). The results showed a strong correlation between fruits and their components (P < 0.05). Tree diameter was very weakly correlated with fruit traits. There was a high level of variation in fruit characteristics and components within and between populations. The within-population variation accounted for the greatest part (67–100%) of the total variation. Many trees, mainly from the drier zones, showed superior phenotypic traits. Five groups of trees which represented different fruit morphotypes were identified for various prospective exploitations. The results strongly support the implementation of preliminary practical conservation action and domestication of S. birrea in West Africa.  相似文献   
295.

Background

Mycobacterioses in animals cause economical losses and certain Mycobacterium avium subspecies are regarded as potential zoonotic agents. The evaluation of the zoonotic risk caused by M. avium subspecies requires information about the quantities of Mycobacterium strains in infected animals. Because M. avium subspecies in pig tissues are difficult or even impossible to quantify by culturing, we tested the suitability of a culture-independent real-time quantitative PCR (qPCR) assay for this purpose.

Methods

Mycobacterial DNA was extracted from porcine tissues by a novel method and quantified by Mycobacterium genus specific qPCR assay targeting the 16S rRNA gene.

Results

The response of the qPCR assay to the amount of M. avium subspecies avium mixed with porcine liver was linear in the range of approximately log105 to log107Mycobacterium cells per 1 g of liver. The assay was validated with three other M. avium subspecies strains. When the assay was applied to porcine lymph nodes with or without visible lesions related to Mycobacterium avium subspecies infections, around 104–107 mycobacterial genomes per gram of lymph nodes were detected.

Conclusions

The qPCR assay was found to be suitable for the quantification of Mycobacterium avium subspecies in porcine lymph nodes and liver.  相似文献   
296.
Phenolic content and antioxidant capacity of muscadine grapes   总被引:10,自引:0,他引:10  
Fruits of 10 cultivars of muscadine grapes (five bronze skin and five purple skin) grown in southern Georgia were separated into skin, seed, and pulp. Each fruit part and the leaves from the corresponding varieties were extracted for HPLC analysis of major phenolics. Total phenolics were determined colorimetrically using Folin-Ciocalteu reagent. Total anthocyanins were determined according to a pH-differential method, using a UV-visible spectrophotometer. Antioxidant capacity was determined by the Trolox equivalent antioxidant capacity (TEAC) assay. Gallic acid, (+)-catechin, and epicatechin were the major phenolics in seeds, with average values of 6.9, 558.4, and 1299.4 mg/100 g of fresh weight (FW), respectively. In the skins, ellagic acid, myricetin, quercetin, kaempferol, and trans-resveratrol were the major phenolics, with respective average values of 16.5, 8.4, 1.8, 0.6, and 0.1 mg/100 g of FW. Contrary to previous results, ellagic acid and not resveratrol was the major phenolic in muscadine grapes. The HPLC solvent system used coupled with fluorescence detection allowed separation of ellagic acid from resveratrol and detection of resveratrol. Reported here for the first time are the phenolic content and antioxidant capacity of muscadine leaves. Major phenolics in muscadine leaves were myricetin, ellagic acid, kaempferol, quercetin, and gallic acid, with average concentrations of 157.6, 66.7, 8.9, 9.8, and 8.6, respectively. Average total phenolics were 2178.8, 374.6, 23.8, and 351.6 mg/g gallic acid equivalent in seed, skin, pulp, and leaves, respectively. Total anthocyanin contents were 2.1 and 132.1 mg/100 g of FW in the skins of bronze and purple grapes, respectively, and 4.3 and 4.6 mg/100 g of FW in seeds and pulps, in that order. Antioxidant capacity values were, on average, 2.4, 12.8, 281.3, and 236.1 microM TEAC/g of FW for pulps, skins, seeds, and leaves, respectively.  相似文献   
297.
This report documents the case presentation, evaluation, treatment and outcome of 5 horses with an osseous cystlike lesion (OCLL) of the intertubercular groove of the proximal aspect of the humerus. In 3 of the 5 cases, delayed phase gamma scintigraphic findings demonstrated increased radiopharmaceutical uptake in the region of the intermediate tubercle of the proximal humerus of the affected limb, demonstrating increased bone remodelling in this region. In 4 of the 5 horses, an OCLL was identified in the intermediate tubercle of the proximal humerus, and in one horse the OCLL was identified in the greater tubercle. Medial‐lateral and craniomedial‐caudolateral oblique radiographic views were helpful to see the lesions in all cases. Ultrasonography confirmed the location of the subchondral and fibrocartilage defect associated with the OCLL and confirmed communication of the cyst with the lateral intertubercular groove of the humerus in 3 of the 5 cases. Ultrasonography also confirmed a variable degree of bicipital tendonitis in 3 of the horses. OCLL of the lateral intertubercular groove of the proximal humerus should be considered in the evaluation of any mature horse with lameness isolated to the bicipital bursa. Development of these OCLL may be a result of trauma or altered limb biomechanics as a result of shoulder osteoarthritis or concurrent chronic lameness, which leads to disruption or thinning of the fibrocartilage, remodelling of the subchondral bone and subsequent cyst development.  相似文献   
298.
A 30-year-old palomino Standardbred horse was seen with a persistent penile squamous cell carcinoma. After failure using multiple treatments, surgical removal was successfully carried out under local anesthesia using Mohs micrographically controlled surgery. Subsequent examination of the malignant tissue identified bovine papillomavirus exclusively within the nuclei and cytoplasm of tumor cells. The use of Mohs surgery would appear to be useful as an effective, precisely controlled treatment for managing genital squamous cell carcinoma in equine subjects. The presence of papillomavirus within tumor cells would suggest the possibility of causation by an oncogenic papilloma virus and would indicate that careful monitoring of the surgical site should be performed.  相似文献   
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