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51.
Theileria annulata is endemic in northern Sudan, hindering all efforts at upgrading cattle for milk production. T. lestoquardi clinical cases occur throughout the year and causes annual outbreaks that result in substantial losses in sheep. In the northern Sudan both cattle and small ruminants are frequently raised together and/or share common grazing grounds at river banks. In an attempt to evaluate field cross infectivity of Theileria lestoquardi and T. annulata in cattle and sheep respectively, a PCR analysis was carried out on samples collected from closely reared sheep and cattle using both T. annulata and T. lestoquardi specific primers. A total of 19 sheep out of 51 (37.3%) were positive for T. lestoquardi while four sheep (7.8%) showed T. annulata specific amplicons. A total of 38 out of 52 (73.1%) surveyed cattle were PCR positive for T. annulata and only two (3.8%) showed T. lestoquardi specific bands. These findings indicate complex epidemiology of both infections in areas where both parasites are transmitted by the same vector and call for further investigations of this phenomenon.  相似文献   
52.
For investigating the effects of physiologically relevant heat shock, buffalo oocytes/embryos were cultured at 38.5°C (control) or were exposed to 39.5°C (Group II) or 40.5°C (Group III) for 2 h once every day throughout in vitro maturation (IVM), fertilization (IVF) and culture (IVC). Percentage of oocytes that developed to 8‐cell, 16‐cell or blastocyst stage was lower (p < 0.05) and the number of apoptotic nuclei was higher (p < 0.05) for Group III > Group II > controls. At both 8–16‐cell and blastocyst stages, relative mRNA abundance of stress‐related genes HSP 70.1 and HSP 70.2 and pro‐apoptotic genes CASPASE‐3, BID and BAX was higher (p < 0.05) in Groups III and II than that in controls with the exception of stress‐related gene HSF1. Expression level of anti‐apoptotic genes BCL‐XL and MCL‐1 was also higher (p < 0.05) in Groups III and II than that in controls at both 8–16‐cell and blastocyst stages. Among the genes related to embryonic development, at 8–16‐cell stage, the expression level of GDF9 was higher (p < 0.05) in Group III than that in controls, whereas that of GLUT1, ZAR1 and BMP15 was not significantly different among the three groups. At the blastocyst stage, relative mRNA abundance of GLUT1 and GDF9 was higher (p < 0.05) in Group II than that in controls, whereas that of ZAR‐1 and BMP15 was not affected. The results of this study demonstrate that exposure of buffalo oocytes and embryos to elevated temperatures for duration of time that is physiologically relevant severely compromises their developmental competence, increases apoptosis and affects stress‐, apoptosis‐ and development‐related genes.  相似文献   
53.
When buffalo embryonic stem (ES) cell–like cells that expressed surface markers SSEA‐4, TRA‐1‐60, TRA‐1‐81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX‐1 and NUCLEOSTEMIN as confirmed by RT‐PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three‐dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF‐68 and NESTIN (ectodermal lineage), BMP‐4 and α‐skeletal actin (mesodermal lineage), and α‐fetoprotein, GATA‐4 and HNF‐4 (endodermal lineage). When these EBs were cultured on gelatin‐coated dishes, they spontaneously differentiated to several cell types such as epithelial‐ and neuron‐like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10?8 m or 10?7 m retinoic acid for 25 days, ES cells could be directed to form muscle cell–like cells, the identity of which was confirmed by expression of α‐actinin by immunofluorescence and of MYF‐5, MYOD and MYOGENIN genes by RT‐PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell–like cells to undergo directed differentiation to cells of skeletal myogenic lineage.  相似文献   
54.
OBJECTIVE: To determine magnetic resonance imaging (MRI) abnormalities in dogs with intervertebral disk disease (IVDD) and develop a classification scheme for IVDD in dogs based on MRI findings. DESIGN: Retrospective case series. ANIMALS: 69 dogs. PROCEDURE: Medical records of dogs admitted because of thoracolumbar IVDD in which MRI of T9 through L7 had been performed were reviewed. RESULTS: A total of 759 intervertebral disk spaces were examined. Of these, 342 (45.1%) were classified as having a normal MRI appearance; the remaining 417 (54.9%) had various types of IVDD. Disk degeneration was identified in 276 disk spaces in 56 dogs, bulging of the intervertebral disk was identified in 37 disk spaces in 24 dogs, disk protrusion was identified in 54 disk spaces in 32 dogs, and disk extrusion was identified in 50 disk spaces in 48 dogs. Cartilage endplate changes were identified in 35 vertebrae in 17 dogs, and increased signal intensity of the spinal cord was identified in 21 dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Four types of IVDD (disk degeneration, bulging of the intervertebral disk, disk protrusion, and disk extrusion) were identified on the basis of MRI findings in dogs with thoracolumbar IVDD. We recommend that a standardized nomenclature be adopted for the various types of thoracolumbar IVDD in dogs.  相似文献   
55.
The aim of this study was to develop a radiographic standard for the assessment of pulmonary fluid clearance and lung aeration in newborn calves. Caesarean‐delivered mature calves (= 9) underwent lung assessment by thoracic radiography as well as arterial and venous blood gas analysis within the first 30 min, 1, 2, 3, 6, 12 and 24 hr after birth. The results indicated that newborn calves delivered by elective Caesarean section suffered from a physiological combined respiratory and metabolic acidosis with the dominance of respiratory acidosis, and an improvement in these conditions was recorded within 24 hr after birth. Concerning the radiographic results, clear lung fields, improvement in lung expansion, air content of the lung and absence of lung opacification occurred within 24 hr of birth. Furthermore, the ventral lung quadrant showed an improvement in radiographic opacification and lung expansion earlier than the dorsal lung regions. The findings of this study support the potential role of thoracic radiography in the assessment of pulmonary fluid clearance and lung aeration in newborn calves.  相似文献   
56.
57.
As thiamine status of ruminants is adversely affected by rumen acidity, this study investigated whether or not thiamine deficiency occurs in feedlot cattle fed a high concentrate diet. Fifty 1- to 2-year-old feedlot cattle fed a high concentrate diet (75% barley) for at least 3 mo (high concentrate diet group) and 15 healthy feedlot cattle of similar ages (control group) that were fed a low concentrate diet (30% barley) were used. Rumen fluid samples were obtained by rumenocentesis and their pH was determined with a portable pH meter. Blood samples taken from all animals from a jugular vein were used to determine erythrocyte transketolase enzyme activity, and hence thiamine pyrophosphate (TPP) effect. Odor and mean pH values of ruminal fluid samples from the high concentrate diet and control group were acidic (pH 5.3) and aromatic (pH 6.1), respectively. The mean TPP effect % in the high concentrate diet group (47.2 ± 3.2) was significantly higher than in the control group (19.53 ± 2.5) (P < 0.001). The study provides evidence of a TPP effect in feedlot cattle fed a high concentrate diet.  相似文献   
58.
59.
In this study, electromagnetic shielding characteristics of woven fabrics made of hybrid yarns are investigated. For this purpose, initially the hybrid yarns containing stainless steel wire are produced with hollow spindle covering technique, and then eight different fabric samples are produced using these hybrid yarns. Electromagnetic shielding values of fabric samples are determined by a test set up based on enclosure measurement technique. Measurements are made in the frequency range of 30 MHz-9.93 GHz. Test results show that woven fabric samples investigated in this study have 25–65 dB electromagnetic shielding effectiveness for incident frequency. It was also shown that the direction, density and settlement type of conductive hybrid yarn in fabric structure are important parameters affecting electromagnetic shielding characteristics of woven fabrics.  相似文献   
60.
Six calves were immunized with whole egg antigen of Schistosoma bovis emulsified in Freund's adjuvant. The immune response was monitored by agar-gel immunodiffusion (AGID) and enzyme-linked immunosorbent assay (ELISA). Using AGID and ELISA, antibodies to whole egg antigen were detected in sera from all immunized calves, but not in sera from control calves. The immunized calves and six control calves were challenged 6 months after the beginning of the immunization with 20 000 cercariae of Schistosoma bovis administered percutaneously to the shaved tail. There was no significant difference between the immunized and the control calves as judged by fecal and tissue egg counts, worm recovery and hematological parameters. There was a lack of association between antibody production and protection.  相似文献   
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