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1.
A study was conducted in the USA to determine whether transmissible gastroenteritis (TGE) virus could be transmitted from carcases of slaughtered pigs. Transmissible gastroenteritis virus was transmitted to 6-day-old piglets by dosing with homogenates of muscle and lymph node collected from 500 clinically normal pigs at the time of slaughter. All piglets in 2 separately housed litters showed clinical signs of TGE with 5 piglets dying within 10 d of oral dosing with homogenates. Transmissible gastroenteritis virus was isolated from 2 of these piglets and all piglets developed TGE antibody. Transmissible gastroenteritis virus was not isolated in tissue culture from muscle and lymph node homogenates, but was isolated from 4 (0.8%) of 500 tonsil samples collected from the same pigs. A survey of 250 serum samples provided an estimate of the prevalence of slaughtered pigs with TGE antibody of 34.8% in the sample population. The results indicate that carcases of some pigs from TGE endemic areas contain viable TGE virus, and that there would be a substantial risk of introducing TGE virus into Australia by the importation of uncooked pig meat from these areas. 相似文献
2.
David A. Barlow Ph.D. Judith M. Lloyd B.S. HT Paul Hellhake B.S. Jeffrey A. Seder J.D. M.B.A. 《Journal of Equine Veterinary Science》1984,4(2):60-66
Equine skeletal muscle was histologically and histochemically analyzed in orderto measure fiber composition. Well-sampled open muscle biopsies were obtained from the semitendinosus muscle in select yearling Thoroughbreds. Each biopsy was sectioned and stained for the Harris Hematoxylin and Eosin and the modified Gomori Trichrome in order to demonstrate the basic muscle fiber morphology delineating intra and extracellular elements. A thirdstain, CA++ activated myosin Adenosine Triphosphatase at pH 9.4 was used to differentiate between specific types on the basis of enzyme activities. Subsequent differentiation of Type I slow twitch and Type II fast twitch muscle fibers was assessed on the basisof staining intensity. The high predominance of Type II fast twitch fibers ranged from 85.1 to 100 % with a mean of 90.5 %. Racing records, as two- and three-year-olds, were monitored in order to qualitatively compare histochemical results with performance achievements. While caution must be exercised, results of this investigation suggested that it may be possible, at an early age to partially predict the potential of each horse to adapt to training and to compete successfully in races of varying distances. 相似文献
3.
A low molecular weight poly(ethyleneoxide)-poly(butadiene) (PEO-PB) diblock copolymer containing 50 weight percent PEO forms gigantic wormlike micelles at low concentrations (<5 percent by weight) in water. Subsequent generation of free radicals with a conventional water-based redox reaction leads to chemical cross-linking of the PB cores without disruption of the cylindrical morphology, as evidenced by cryotransmission electron microscopy and small-angle neutron scattering experiments. These wormlike rubber micelles exhibit unusual viscoelastic properties in water. 相似文献
4.
HY Jang YH Kim BW Kim IC Park HT Cheong JT Kim CK Park HS Kong HK Lee BK Yang 《Reproduction in domestic animals》2010,45(6):943-950
Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H2O2) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ). The sperm were treated with melatonin in the presence or absence of H2O2 for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H2O2 groups were lower than H2O2 only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos in pigs. 相似文献
5.
HY Jang SJ Ji YH Kim HY Lee JS Shin HT Cheong JT Kim IC Park HS Kong CK Park BK Yang 《Reproduction in domestic animals》2010,45(6):967-974
The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co‐culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide‐induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl‐2, Caspase‐3 and Bax) by RT‐PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co‐cultured with BOEC pre‐treated with astaxanthin (500 μm ) in the presence or absence of sodium nitroprusside (SNP, 1000 μm ) for 24 h. Cell viability in BOEC treated with SNP (50–2000 μm ) lowered, while astaxanthin addition (50–500 μm ) increased it in a dose‐dependent manner. Cell viability in astaxanthin plus SNP (1000 μm ) gradually recovered according to the increase in astaxanthin additions (100–500 mm ). The LPO in astaxanthin group (50–500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p < 0.05). Expression of apoptosis or antioxidant genes was detected by RT‐PCR. Bcl‐2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase‐3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6–7 days under co‐culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μm astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes. 相似文献
6.
This perspective considers genetic disorders of domestic animal populations, in particular their epidemiology and control. Inherited disorders of animals share the same basic molecular biology as those of human beings, but they differ in their epidemiology due largely to the breed structure of the various species, human control of breeding and a greater influence of the founder effect, particularly due to extensive use of a limited number of sires, and inbreeding. Control of genetic disorders in animals is also more practical through extensive screening for disease, or heterozygous animals within defined breed populations, followed by exclusion of affected or carrier animals from breeding. This is assisted by the fact that, within a breed, many inherited monogenic disorders are associated with a single mutation. However some of the more important disorders may be inherited in a non-Mendelian manner, being influenced by multiple genes as well as environmental factors. These aspects are discussed and contrasted with similar aspects in human medical genetics. 相似文献
7.
HT Duong DJ Skarzynski KK Piotrowska‐Tomala MM Bah K Jankowska P Warmowski K Łukasik K Okuda TJ Acosta 《Reproduction in domestic animals》2012,47(6):939-945
Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inactive cortisone to biologically active cortisol (Cr) and that Cr inhibits cytokine‐stimulated prostaglandin F2α (PGF) production. This study was carried out to test the hypothesis that bovine reproductive tract has the capacity to convert cortisone to Cr in vivo and to evaluate the effects of intravaginal application of exogenous cortisone on uterine PGF secretion during the late luteal stage. The temporal relationships between PGF and Cr levels in uterine plasma were also determined. Catheters were inserted into jugular vein (JV), uterine vein (UV), vena cava caudalis (VCC) and aorta abdominalis (AA) of six cows on Day 15 of the oestrous cycle (ovulation = Day 0) for frequent blood collection. On Day 16, the cows were divided randomly into two groups and infused intravaginally with vaseline gel (10 ml; control; n = 3) or cortisone dissolved in vaseline gel (100 mg; n = 3). Blood samples were collected at ?2, ?1, ?0.5, 0, 0.5, 1, 1.5, 2, 3, 4, 5 and 6 h after treatments (0 h). Intravaginal application of cortisone increased plasma concentrations of Cr between 0.5 and 1.5 h in UV, at 0.5 h in VCC, at 1 h in JV and at 1.5 h in AA. The plasma concentrations of PGF in UV and of PGF metabolite in JV were greater at 0.5 and 1 h in the cortisone‐treated animals than in control animals. The levels of PGF in UV blood plasma decreased after Cr reached its highest levels. The overall findings suggest that the female reproductive tract has the capacity to convert cortisone to Cr in vivo. Based on the temporal changes of PGF and Cr levels in the uterine plasma, a biphasic response in PGF secretion was found to be associated to the Cr increase induced by the cortisone treatment at the late luteal stage in non‐pregnant cows. 相似文献
8.
CASE HISTORY: A skeletal disease characterised by dwarfism, limb deformity and sometimes sudden death occurred over a period of 5 years in lambs born on a commercial sheep farm in Southland. The disease showed variable expression and occurred in crossbred sheep. A genetic aetiology was supported by the birth of affected lambs over two seasons in a flock of putative carrier and affected sheep transported to Massey University. CLINICAL FINDINGS: Affected lambs appeared normal at birth but showed evidence of dwarfism, wide-based stance and exercise intolerance as early as 1 week of age. Most died within the first 3 months of life, often after developing bilateral varus deformity of the forelimbs. Some severely-affected lambs died suddenly of respiratory embarrassment, probably due to tracheal collapse. Mildly-affected individuals had a short, blocky stature and some survived to breeding age. PATHOLOGICAL FINDINGS: Gross and microscopic lesions of variable severity were present in the tracheal, articular, epiphyseal and physeal cartilages. In severe cases, articular cartilage in major joints was eroded from weight-bearing surfaces. The trachea was flaccid, abnormally kinked, and had thickened cartilaginous rings and a narrow lumen. Affected sheep that survived to breeding age eventually developed severe degenerative joint disease. Histologically, chondrocytes were disorganised, surrounded by concentric rings of abnormal fibrillar material, and the matrix often contained focal to coalescing areas of chondrolysis. DIAGNOSIS: Inherited chondrodysplasia of Texel sheep. CLINICAL RELEVANCE AND CONCLUSIONS: This chondrodysplasia differs from those previously described in sheep and is considered to be a newly-recognised, recessively-inherited genetic disease of the Texel breed. A defect in the synthesis of glycosaminoglycans in cartilage matrix is suspected. This disease of sheep may provide a suitable model for studying various forms of therapy for human chondrodysplasias. 相似文献
9.
Inherited rickets of Corriedale sheep is of simple autosomal recessive inheritance. The gross and histological lesions include segmental thickening of physes, persistence of hypertrophic chondrocytes at sites of endochondral ossification, excessive osteoclastic resorption, microfractures and wide unmineralised osteoid seams lining trabeculae and filling secondary osteons. Initial testing revealed concentrations of 25-hydroxyvitamin D3 were normal, but those of 1,25-dihydroxyvitamin D3 were increased in serum of affected sheep, suggesting a defect in the vitamin D receptor. However, in vitro studies on cultured skin fibroblasts revealed normal binding and function of the vitamin D receptor. A genome-wide association study was conducted using the Illumina OvineSNP50 BeadChip. A homozygous region of 199 consecutive single-nucleotide polymorphism loci was identified in affected sheep, covering a region of 10 megabase pairs on ovine chromosome 6. Of the 91 candidate genes in this region, dentin matrix protein 1 gene (dmp1) was considered the most likely as it is known to play critical roles in osteocyte maturation and mineral metabolism. Sequencing of DNA from carriers showed a nonsense mutation 253T/C in dmp1. This T/C transition introduced a stop codon (R145X) that could truncate C-terminal amino acids. Using PCR restriction fragment length polymorphism for this mutation, genotyping showed that all affected sheep were “TT” genotypes, and phenotypically normal sheep were either “CT” or “CC”. These findings suggest that a mutation in dmp1 is responsible for inherited rickets of Corriedale sheep. A simple diagnostic test is currently being designed to identify carriers with the defective “T” alleles. 相似文献
10.
Abstract HISTORY: A similar episodic neurological disorder occurred in new born lambs on two unrelated properties involving disparate breeds of sheep. Because of the number of lambs born, cross-breeding and the fact it occurred in some mating groups and not others, a dominant mode of inheritance was, initially and separately, suspected in each case. The sires of affected lambs were apparently normal. Whereas one was New Zealand Romney, the other was a composite breed with East Friesian genetics, but both rams originated from the same source property. To investigate the pathogenesis of the disorder these two rams were acquired and mated with unrelated sheep, under experimental conditions in a more controlled environment. CLINICAL FINDINGS: A proportion of lambs born to both sires exhibited a similar neurological disorder. Some lambs were noted to be abnormal at birth, both on home properties and in the experimental flock. They tended to adopt a head and neck extended posture and were slow to get to their feet and suckle when they then became more or less normal. When forced to move, they and other more robust lambs elicited an asymmetric gait, base-wide extensor hypertonia (hypometria) of thoracic limbs and flexor hypertonia (hypermetria) of pelvic limbs. In some there was nystagmus. After several metres of asymmetric ataxic gait they would fall to one side, sometimes adopting a sitting position. Recovery usually occurred in one to several minutes. As lambs aged, it became more difficult to elicit the episodes of dysfunction and by 6 months of age they appeared normal. DIAGNOSIS: The disorder was diagnosed as a dominant familial episodic cerebellovestibular ataxia inherited as a dominant trait, with incomplete penetration of observed clinical signs and variable expressivity. CLINICAL RELEVANCE: A proportion of affected lambs are likely to die in the neonatal period so the specific nature of the disorder may go unrecognised. Because of incomplete penetrance and varying expressivity, many of the lambs carrying this mutation will survive without showing clinical signs and may enter breeding flocks, where the disorder may be perpetuated and contribute to neonatal deaths. 相似文献