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91.
The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats' milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August 2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected. Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4), 3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton–Valentine leukocidin produced by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity.  相似文献   
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93.
The rock pigeon (RP) and the laughing dove (LD) are common and widely distributed species in African countries, including Egypt. The present work was carried out to characterize the comparative features of the glandular stomach (proventriculus) in these two birds, which share diets and habitats. In both species, the proventriculus is an elongated spindle obliquely situated in the cranial two‐thirds of the body cavity. The length and weight of the proventriculus in the RP were about one and half times greater than that of the LD. Histologically, the proventricular wall generally consisted of the mucosa (thickest), submucosa, muscular and serosa layers. The proventricular glands occupied most of the wall of the proventriculus within the lamina propria of the mucosa. The glands are tubuloalveolar in type, consist of variable shaped lobules and are more condensed in LD than in RP. At the proventricular‐gizzard junction (PGJ), the proventricular glands were observed external to the tubular glands of the gizzard in the RP, whereas in LD, these glands end abruptly and are separated from the tubular glands of the gizzard by a short distance. A scanning electron microscopy (SEM) of the proventricular lumen in RP revealed that the openings of the proventricular glands have an irregular outline surrounded by concentrically arranged mucosal folds that resemble a rosette shape. In the LD, these openings have a regular outline surrounded by thinner, widely spaced mucosal folds. To our knowledge, these results identified the structure of the proventriculus in RP and LD for the first time.  相似文献   
94.
The aim of the study is to determine the effect of different growth vigorous rootstocks on phenolic compounds in leaves of apple. For this purpose it was used the leaves of cultivar ‘Red Chief’ grafted on dwarf (M9), semi-dwarf (M26) and semi-vigorous (MM106) rootstocks. During mid-July, the leaf samples were taken from the middle part of annual shoots. Phenolics of the leaves were determined by HPLC analysis. While significant differences among the rootstocks for p-hydroxybenzoic acid, eriodictyol, ferulic acid and p-coumaric acid were detected, these differences were insignificant for gallic acid and quercetin. It was shown that semi-vigorous rootstocks (MM106) had higher phenolic contents in total than the other two dwarf rootstocks. In addition, apigenin-7-glucoside, chlorogenic acid, caffeic acid, rosmarinic acid, epicatechin, syringic acid, catechin, rutin, resveratrol, hesperidin, naringenin, luteolin, apigenin and acacetin could not to be detected. Data showed that there is the relationship between growth vigour and phenolic contents of apple leaves. Especially, p-hydroxy benzoic acid and p-coumaric acid contents were higher in semi-vigorous rootstock than in dwarf rootstock.  相似文献   
95.
This study was conducted in 2007–2008 to determine the effects of different irrigation regimes on yield, quality and water-yield relationships of young dwarf ‘Gala, Galaxy’ apple trees in Isparta-Turkey. Irrigation water was applied based on a ratio of class A pan evaporation (rates of 0.0 (kcp0), 0.25 (kcp1), 0.50 (kcp2), 0.75 c (kcp3), 1.00 (kcp4) and 1.25 (kcp5)) with 5-day intervals. The effects of irrigation regimes on yield and fruit weight were statistically significant. Seasonal evapotranspiration was measured as 246.5–608.2 mm and 289.3–631.9 mm in 2007 and 2008, respectively. Water use efficiency lead to a yield ranging from 0.0023 to 0.0055 t ha?1mm?1 and from 0.0033 to 0.0111 t ha?1mm?1 and irrigation water use efficiency varies from 0.0009 to 0.0073 t ha?1mm?1 and from 0.0045 to 0.0186 t ha?1mm?1 in 2007 and 2008, respectively. The annual average yield response factor, ky, was 1.22. As a result of the research, it was concluded that the irrigation schedule for the 0.75 kcp3 treatment, applying 0.75 of evaporation from class A pan, could be used in the irrigation of young dwarf apple trees without evident reduction in yield and that high water use efficiencies could be obtained.  相似文献   
96.
The present work was designed to investigate the microscopic structure of the oesophagus in the southern white-breasted hedgehog (Erinaceus concolor) using histochemical staining, Scanning electron microscope (SEM), and stereological procedures. Four adult males were included in our study. Serial sections of the entire length of the oesophagus were stained with aldehyde fuchsin, alcian blue (pH 2.5), Periodic acid Schiff (PAS), and Masson's trichrome. Then, the total volume of the oesophagus, and the total volume of its different layers, were estimated using Cavalieri's principle. The oesophageal epithelium was a non-keratinized stratified squamous type. Muscularis mucosa was present as a thick layer between lamina propria and submucosa and its thickness was increased toward the stomach. Tunica submucosa was a loose connective tissue containing an oesophageal gland with PAS-positive and AB-positive reactions throughout the submucosa and become denser toward the stomach. The tunica muscularis consisted of two distinct striated muscle layers, and its thickness was decreased toward the stomach. On SEM images, the cervical and thoracic oesophagus showed shallow folding, while the abdominal part had deeper folds. The present findings indicate that the histological properties of the oesophagus in southern white-breasted hedgehogs have slight similarities with rodents and considering its epithelium, submucosal glands and tunica muscularis more resemble with dog oesophagus. The obtained results may be quite helpful to improve the current knowledge of the histophysiology of the hedgehog gastrointestinal tract as a member of eulipotyplan mammals and as a pet for biologists and veterinarians.  相似文献   
97.
Progesterone has neuroprotective effects including augmentation of myelination in the central and peripheral nervous system. This study was designed to determine if demyelinating lesions in the cerebellum resulting from canine distemper virus (CDV) infection are associated with progesterone levels. Progesterone was measured using radioimmunoassay in samples of the cerebellum, corpus callosum, medulla oblongata, parietal, frontal, temporal, and occipital cortices as well as cerebrospinal fluid (CSF) and plasma collected from ten CDV infected and six non-infected dogs. The cerebellum progesterone level was significantly different between CDV infected (0.66+/-0.09 ng/g) and control dogs (1.14+/-0.09 ng/g) (p<0.001); however, no difference was observed for the other CNS regions, plasma and CSF (p>0.05). The cerebellum progesterone level was also significantly different between acute (0.71+/-0.0 5 ng/g) and chronic cases (0.61+/-0.09 ng/g) (p<0.05). The CDV infected cerebella were also categorized histopathologically according to the severity of demyelinating lesions as mild (n=5), moderate (n=2), or severe (n=3) among which the cerebellum progesterone level was significantly different (p<0.05). Progesterone concentration was 0.71+/-0.05 ng/g in mild, 0.65+/-0.10 ng/g in moderate, and 0.56+/-0.07 ng/g in severe cases. In conclusion, progesterone concentration decreases in the cerebellum in CDV infection and the severity of demyelinating lesions is the greatest in cerebella with the lowest progesterone concentrations. The results suggest that local impairment of progesterone metabolism may be associated with the initiation and progression of cerebellar lesions in CDV infection.  相似文献   
98.
The neuronal elements of the vomeronasal organ (VNO) of camel were investigated immunohistochemically. PGP 9.5 labeled the receptor cells in the vomeronasal sensory epithelium, but not the supporting or basal cells. OMP stained some receptor cells, but no immunoreactive signals for OMP were detected in the non-sensory epithelium. PLCβ2 labeled scattered cells in the sensory epithelium and a larger number of cells in the non-sensory epithelium. Double labeling immunohistochemistry revealed that the PLCβ2-positive cells were surrounded by substance P-positive nerve fibers. Collectively, these data suggest that the camel VNO bears, in addition to the mature vomeronasal receptor cells, trigeminally-innervated solitary chemosensory cells which are expected to play a substantial role in the control of stimulus access to the VNO.  相似文献   
99.
Sea cucumbers belonging to the Holothuroidea class are a group of worm-like and soft-bodied echinoderms that live in nearly all marine environments. Mediterranean Holothuria tubulosa is an economic sea cucumber species found in Turkish seas. This study aimed to present the first report of detailed amino acid profile and investigate the biochemical and nutritional characteristics of H. tubulosa seasonally collected from one of the densest natural beds, located at Çanakkale Strait (Southern Coast of Marmara Sea), Turkey. According to our results, the highest protein, lipid, and ash contents (%) were found to be 10.2, 1.9, and 5.1, respectively. The highest percentages of saturated, monounsaturated, and polyunsaturated fatty acids were 42.9, 28.3, and 37.8, respectively. Total amino acids (mg/g crude protein) ranged between 867.2 and 974.0 among all seasons. All essential amino acids were found in body wall tissues and ranged between 7.1 and 5.9. Mineral composition was found to be desirable at the recommended and threshold levels. In general, the proximate composition of H. tubulosa was directly affected by seasons (p < .05); however, amino acid, fatty acid, and mineral compositions were found to be similar among all seasons, except summer (p > .05).  相似文献   
100.
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