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81.
Vitrification of in vitro matured oocytes of Mangalica and Large White pigs   总被引:1,自引:0,他引:1  
The breeding of Mangalica, a native pig breed in Hungary, had been started in 1833, but this pig breed almost became extinct in Hungary in the past decades. In 1991, the number of sows was only 200. Although in these days the existing Mangalica population consists of more than 6000 animals representing different colour variations, the preservation of this traditional pig breed is still very important. Vitrification is a potential tool for the preservation of gametes and embryos of these animals. The aim of this study was to investigate the effects of vitrification on the developmental competence of Mangalica (M) and Large White (LW) oocytes following fertilisation. The oocytes were vitrified by the Open Pulled Straw (OPS) method using different concentrations of ethylene glycol and dimethyl sulphoxide as cryoprotectants. After rehydration the oocytes underwent in vitro fertilisation; the resultant zygotes were then cultured in vitro for four days to assess embryonic development. In the first experiment, in vitro maturation of M and LW oocytes was compared. No significant difference was observed in the nuclear maturation rate of LW and M oocytes. In the second experiment, the sensitivity of oocytes to vitrification was examined by evaluating oocyte morphology after thawing. A higher percentage of LW oocytes showed normal morphology compared to M oocytes, indicating that Mangalica oocytes are more sensitive to cryoprotectants than Large White oocytes. After warming and in vitro fertilisation, more than 50% of the oocytes started embryonic development and by the end of the incubation period morula stage embryos had developed in both groups. The results show that the OPS vitrification technique is well suited to preserve Mangalica oocytes and from these oocytes morula embryos can be produced.  相似文献   
82.
Background: Growing interest in veterinary oncohematology has facilitated the recent development and advancement of new techniques, such as flow cytometry, for immunophenotyping hematopoietic neoplasia in animals. Objective: The aim of this retrospective study was to characterize hematologic abnormalities and flow cytometric immunophenotyping (FCI) results in cases of hematopoietic neoplasia in dogs. Methods: Signalment, CBC data, and FCI results were obtained for 210 dogs with blood samples submitted to our laboratory. Immunophenotyping was carried out using an Epics XL‐MCL flow cytometer and a panel of 10 antibodies (CD45, CD3, CD4, CD8, CD79, CD21, CD14, CD34, CD41/61, CD61). The prevalence and severity of hematologic abnormalities was determined for the different types of hematopoietic neoplasms. Results: Based on cell morphology and phenotype, cases were classified as: acute lymphoblastic leukemia (ALL, n=51), acute myeloid leukemia (AML, n=33), chronic lymphocytic leukemia (CLL, n=61), and leukemic high‐grade lymphoma (L‐HGL, n=65). Most cases of ALL (47/51) and L‐HGL (41/65) had a B‐cell phenotype, while most cases of CLL (54/61) had a T‐cell phenotype, with a high prevalence of the large granular lymphocyte subtype (49/61). Anemia was found in 85% of all cases and was significantly more severe in ALL and AML compared with CLL and L‐HGL. Neutropenia was seen in 64–78% of acute leukemias (AML and ALL) in contrast to no cases of CLL and 11% of L‐HGL. Thrombocytopenia was seen in 88–90% of acute leukemias in contrast to 15% of CLL and 40% of L‐HGL. Thrombocytopenia was more prevalent (71% vs 22%) and significantly more severe in T‐cell vs B‐cell L‐HGL. Conclusion: A standard CBC is useful in suggesting the type of hemoproliferative disorder and may also help to predict the phenotype, especially in cases of L‐HGL.  相似文献   
83.

Background

It was recently shown that niacin supplementation counteracts the obesity-induced muscle fiber transition from oxidative type I to glycolytic type II and increases the number of type I fibers in skeletal muscle of obese Zucker rats. These effects were likely mediated by the induction of key regulators of fiber transition, PPARδ (encoded by PPARD), PGC-1α (encoded by PPARGC1A) and PGC-1β (encoded by PPARGC1B), leading to type II to type I fiber transition and upregulation of genes involved in oxidative metabolism. The aim of the present study was to investigate whether niacin administration also influences fiber distribution and the metabolic phenotype of different muscles [M. longissimus dorsi (LD), M. semimembranosus (SM), M. semitendinosus (ST)] in sheep as a model for ruminants. For this purpose, 16 male, 11 wk old Rhoen sheep were randomly allocated to two groups of 8 sheep each administered either no (control group) or 1 g niacin per day (niacin group) for 4 wk.

Results

After 4 wk, the percentage number of type I fibers in LD, SM and ST muscles was greater in the niacin group, whereas the percentage number of type II fibers was less in niacin group than in the control group (P < 0.05). The mRNA levels of PPARGC1A, PPARGC1B, and PPARD and the relative mRNA levels of genes involved in mitochondrial fatty acid uptake (CPT1B, SLC25A20), tricarboxylic acid cycle (SDHA), mitochondrial respiratory chain (COX5A, COX6A1), and angiogenesis (VEGFA) in LD, SM and ST muscles were greater (P < 0.05) or tended to be greater (P < 0.15) in the niacin group than in the control group.

Conclusions

The study shows that niacin supplementation induces muscle fiber transition from type II to type I, and thereby an oxidative metabolic phenotype of skeletal muscle in sheep as a model for ruminants. The enhanced capacity of skeletal muscle to utilize fatty acids in ruminants might be particularly useful during metabolic states in which fatty acids are excessively mobilized from adipose tissue, such as during the early lactating period in high producing cows.  相似文献   
84.
It is well known that heart rate or arterial blood pressure may increase in response to surgical stimulation despite the absence of a purposeful movement. However, there is limited information regarding anesthetic requirement for blunting adrenergic response in dogs. This study was designed to compare the minimum alveolar concentrations of sevoflurane required to prevent autonomic response (MAC-BAR) and purposeful movement (MAC) in dogs. Sevoflurane MAC-BAR and MAC were determined in 5 beagle dogs by judging dogs' response to a noxious electrical stimulus applied to the gingiva. The sevoflurane MAC-BAR was significantly higher than MAC (3.33 ± 0.48 vs 2.10 ± 0.28%, P=0.005). These results suggested that autonomic responses occurred at sevoflurane anesthetic concentrations at which purposeful movements were absent.  相似文献   
85.
Neonatal Japanese Black (JB) calves show a high incidence of diarrhea. The objective of this study was to analyze the immune cell populations of neonatal JB calves in detail and examine its correlation with the incidence of diarrhea immediately after birth. Understanding the immune cell populations is helpful in clinics in order to determine the condition of the immune system for prevention of diseases. Blood samples were obtained from JB calves on the day of birth. The peripheral leukocyte populations were analyzed separately for calves that had diarrhea within 2 weeks after birth (diarrhea group; n = 26) and for calves without diarrhea (control group; n = 74). The numbers of the peripheral blood CD3(+)TcR1-N12(+) and CD8(+) T cells were significantly lower in the diarrhea group compared with the control group. These findings suggest that the congenital lower peripheral γδ and CD8(+) T cells results in a high risk of diarrhea in neonatal JB calves.  相似文献   
86.
A 1‐year‐old, female intact Pug dog was presented to the Small Animal Teaching Hospital of the University of Liverpool with a 4‐week history of progressive multifocal intracranial signs. Magnetic resonance imaging (MRI) detected multiple hemorrhagic lesions in the brain. The Baermann and zinc sulfate flotation tests with centrifugation, performed on fecal samples, were positive for lungworm larvae and an antigenic test confirmed Angiostrongylus vasorum infection. Anthelmintic treatment was started with a consequent marked clinical improvement. Seventy days later, the dog was clinically normal, and no larvae were detected on the Baermann test. Repeat MRI of the brain revealed marked improvement of the hemorrhagic lesions. Cerebrospinal fluid analysis (CSF) showed marked eosinophilic pleocytosis, and anthelmintic treatment was restarted. A follow‐up CSF analysis 4 months after the first presentation revealed resolution of the eosinophilic pleocytosis. This is the first case report of marked eosinophilic pleocytosis associated with neural A vasorum infection in a dog. The CSF eosinophilic pleocytosis persisted for several weeks after treatment, even in the absence of concurrent clinical signs and with a negative A vasorum Baermann test.  相似文献   
87.
Gene flow among populations in different selective environments should favor the evolution of phenotypic plasticity over local adaptation. Plasticity in development is a common response to long‐term hypoxia in some widespread African fishes, including Pseudocrenilabrus multicolor, a cichlid that exploits both normoxic (high oxygen) rivers/lakes and hypoxic (low oxygen) swamps. Previous studies have shown that fish from normoxic and hypoxic sites differ in many traits, including gill size, brain size and body shape, and that much of this variation reflects developmental plasticity. However, these earlier studies focused on areas in Uganda where gene flow between swamp and river or lake populations is high. In this study we tested the hypothesis that P. multicolor from a relatively isolated lake population (Lake Saka, Uganda) exhibit low levels of plasticity in traits related to oxygen uptake. Multiple broods of P. multicolor from Lake Saka were reared under low and high dissolved oxygen, and traits related to gill size, brain mass and body shape were quantified. Surprisingly, both gill size and brain mass showed high levels of developmental plasticity. We suggest that high levels of plasticity, particularly in the gill size of P. multicolor, reflects low costs of maintaining the plastic response, even in relatively isolated populations.  相似文献   
88.
OBJECTIVE: To determine the amount of time required for surface temperatures of thoracic and pelvic limbs in horses to return to pre-exercise temperatures after high-speed treadmill exercise, as detected via infrared thermographic imaging. DESIGN: Prospective study. ANIMALS: 6 Thoroughbreds. PROCEDURES: All horses had been trained on and conditioned to use of a high-speed treadmill. Baseline thermographic images were obtained 3 days prior to exercise (baseline). Horses were exercised on a treadmill at a walk for 5 minutes, a slow trot (3 m/s) for 5 minutes, a trot (5 to 6 m/s) for 5 minutes, and a slow gallop (6 to 8 m/s) for 5 minutes, then back to a trot for 3 minutes, a slow trot for 3 minutes, and a walk for 3 minutes prior to stopping. Thermal images were obtained immediately after stopping exercise (0 minutes) and 5, 15, 45, and 60 minutes and 6 hours after stopping exercise. Ambient temperature surrounding each horse was recorded. RESULTS: In all regions, significant differences in surface temperatures were detected between thermograms obtained before exercise and those obtained immediately after, 5 minutes after, and 15 minutes after exercise was stopped. There were no significant differences in surface temperatures between thermograms obtained before exercise and those obtained > or = 45 minutes after exercise was stopped. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, images generated via infrared thermography are not influenced by exercise-generated heat > or = 45 minutes after exercise is stopped.  相似文献   
89.
The aim of this work was to identify the predominant yeast species present at different anatomical sites in healthy dogs and to determine their in vitro antimicrobial susceptibility using a broth microdilution assay. Samples were collected from the preputial, vaginal, oral and perianal mucosae and the isolates cultured were identified according to their morphological characteristics and biochemical profile. Malassezia pachydermatis was the most commonly isolated yeast, followed by Candida parapsilosis, Candida tropicalis, Candida albicans, Saccharomyces cerevisiae and Rhodotorula spp.Minimum inhibitory concentrations of the azole derivatives ketoconazole, itraconazole and fluconazole against Candida spp. were 0.03–16 μg/mL, 0.06 to >16 μg/mL and 0.5–64 μg/mL, respectively and Candida isolates were sensitive to caspofungin and amphotericin B. Although all isolates of M. pachydermatis were sensitive to itraconazole, fluconazole, ketoconazole and amphotericin B, they were found to be resistant to caspofungin. The study has highlighted that Candida spp., M. pachydermatis, S. cerevisiae and Rhodotorula spp. are part of the normal canine surface microbiota and some of these organisms exhibit in vitro resistance to commonly used antimicrobials.  相似文献   
90.
A general index of the second 25 volumes of 'Kulturpflanze' 1978–1990/'GRACE' (Genetic Resources and Crop Evolution) 1992–2003 is provided. Its predecessor covered the first 25 volumes of the periodical 'Die Kulturpflanze' and appeared in 1977. The index can be considered as a unique source for research in plant genetic resources.  相似文献   
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