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1.
The present study was designed to examine the effects of cell-cycle synchronization protocols, such as confluent, roscovitine treatment and serum starvation, in bovine foetal fibroblasts on synchronization accuracy at G0/G1, viability, apoptosis, necrosis and ploidy for use as a nuclei donor. The cells in 5-10 passages were randomly allocated into three treated groups. Cells were cultured either in Dulbecco's modified Eagle's medium (DMEM) + 10% foetal bovine serum (FBS) until 90% confluent (group 1, confluent), in DMEM + 10% FBS + 30 microM roscovitine for 12 h (group 2, roscovitine), or in DMEM + 0.5% FBS for 5 days (group 3, serum starvation). Most of the cells (>80%) in all groups were arrested at the G0/G1 stage. Although the rates did not differ, cells in group 1 showed an increased cell population arrested at the G0/G1 phase. Significantly (p < 0.05) higher rates of apoptosis occurred in group 3 than in group 1 and 2 (10% vs 6% and 6%, respectively). No differences in chromosomal abnormality were observed among groups. However, by increasing the number of cell culture passages up to 15, significantly (p < 0.05) higher chromosomal abnormality was observed than in 5 and 10 passages (39% vs 28% and 23%, respectively) in group 1. The results clearly indicated that bovine foetal fibroblasts could be effectively synchronized at G0/G1 stages by all the three different treatments, confluent, roscovitine and serum starvation. However, cells in confluent showed reduced apoptosis and necrosis when they underwent 5-10 passages, exhibiting increased percentage of cells with stable chromosome diversity. Hence, cells in confluent merit further studies before they could be used as nuclear donors.  相似文献   
2.
Rabbit does from R line selected for growth rate present a low reproductive performance and this study aimed to evaluate both the recovery efficacy and viability of recovered embryos after vitrification and the reproductive performance of donor does subjected to in vivo recovery. Does were divided into three groups: 28 does without in vivo recovery (control), 25 does in which in vivo recovery was started in the nulliparous state (group 1) and 30 does with at least one litter before in vivo recovery (group 2). Does were superovulated with a single subcutaneous injection of 50 IU of equine chorionic gonadotropin (eCG) per female, and were then artificially inseminated 60 h later and immediately administered an intravenous dose of 75 IU of human chorionic gonadotropin (hCG) per female. Does from group 1 and 2 were recovered in vivo 76-80 h post-insemination by repeated laparoscopies at one to four times and permitted one or two parturitions between recoveries [in vivo (IV) recovery]. At the end of the experiment, about 16 does of all groups were recovered post-mortem (PM recovery). All normal embryos were vitrified, devitrified and then cultivated in vitro to evaluate the viability after thawing. A significant increase in the ovulation rate was found in does recovered PM than in those recovered IV in the nulliparous state. However, no significant differences were observed in the recovery rate, the donor rate, the number of normal embryos recovered with at least one normal embryo per doe and the viability after thawing between the PM and IV groups. A significant decrease in the fertility rate, total born, live born and weaned kids was found for does from group 1 in comparison with does from group 2. Results support the use of repeated laparoscopy to increase the number of recovered embryos per donor doe especially in such R line does, if they are permitted to produce at least one litter before the beginning of in vivo recovery.  相似文献   
3.
Egg yolk is a common additive to sperm cryopreservation diluents. Because of its animal origin, however, it also represents a potential risk of microbiological contamination in the diluent. This potential contamination can be avoided by using powdered egg yolk, instead of fresh egg yolk, as it is pasteurized. This study was conducted to determine ram sperm cryosurvival was affected by the type of egg yolk used (powdered egg yolk or fresh egg yolk) and by yolk concentration (10, 15 or 20%) in the diluent. Microbiological analyses were also performed to quantify the microbiological contamination in the diluents containing the two types of egg yolk. Sperm cryosurvival was determined by motility and morphology analyses after thawing. Motility parameters were assessed using a computer-assisted sperm analysis (CASA) system, and the percentage of sperm with a normal apical ridge was evaluated using a differential interference contrast microscope. No significant differences were observed between diluents in the percentage of sperm with normal apical ridge. However, higher percentages of total motile cells were observed for samples containing powdered egg yolk (69%) compared to samples containing fresh egg yolk (60%). However, sperm in diluents containing fresh egg yolk, exhibited higher values for average-path velocity, straight-line velocity and beat cross frequency and lower values for amplitude of lateral head displacement (p <0.05), compared to cells in diluents containing powdered egg yolk. Microbiological contamination was similar (<200 CFU/ml) in both diluents, and no bacterial growth was observed in either, when antibiotics were added. Therefore, powdered egg yolk can be effective used in diluents for the freezing of ram semen. However, the in vivo fertility of sperm frozen in diluents containing powdered egg yolk should be tested, as some motility parameters were different for sperm treated with powdered egg yolk compared to fresh egg yolk.  相似文献   
4.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
5.
ABSTRACT

Case history and clinical findings: A flock of 20 sheep was kept within three paddocks on a single property. None of the animals in the flock had been vaccinated against any disease for at least three years. Abdominal bloating and haemorrhagic diarrhoea were observed in Lamb 1 at 24 hours-of-age. The lamb subsequently died within an hour of the onset of clinical signs. Lamb 2 was 3-days-old when observed to be recumbent with opisthotonus. The lamb was treated with dextrose, vitamins B1 and B12, and penicillin G, but died 4 hours later.

Pathological findings: Examination of Lamb 1 revealed markedly increased gas within the peritoneum and within dilated loops of intestine. The intestines were dark red and contained large quantities of haemorrhagic fluid. Histology of the intestines revealed peracute mucosal necrosis with minimal accompanying inflammation. The intestinal lumen contained cell debris, haemorrhage, and myriad large Gram-positive bacilli. The intestines of Lamb 2 did not appear bloated or reddened. However, multiple fibrin clots were visible within the pericardial sac. Histopathological examination revealed small foci of necrosis within the mucosa of the distal intestine. The necrotic foci were often associated with large numbers of large Gram-positive bacilli.

Immunohistochemsitry and molecular biology: Intestinal samples from Lamb 1 were processed for Clostridium perfringens immunohistochemistry, which revealed large numbers of intralesional, positively immunostained rods. Fragments corresponding to the expected sizes for genes encoding alpha, beta, and epsilon C. perfringens typing toxins were amplified by PCR from DNA extracted from formalin-fixed sections of intestine.

Diagnosis: Lamb dysentery due to C. perfringens type B.

Clinical relevance: C. perfringens bacteria have a worldwide distribution, but disease due to C. perfringens type B has only been diagnosed in a small number of countries and has never been reported in New Zealand or Australia. C. perfringens type B produce both beta toxin and epsilon toxins, therefore both haemorrhagic enteritis and systemic vascular damage can develop. As many animals are exposed to C. perfringens without developing disease, there must be additional unknown factors that resulted in disease in these particular sheep. Vaccines that specifically protect against C. perfringens type B are available and may be recommended for use in smaller non-commercial flocks, as in the present case.  相似文献   
6.
BackgroundThe microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen.ObjectivesThe present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees.MethodsA procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration.ResultsUR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 104 spores/bee, and the stable detection level was ≥ 2.40 × 105 spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 104 copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min.ConclusionsUR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.  相似文献   
7.
Hepatitis E outbreaks are a serious public health concern in developing countries. The disease causes acute infections, primarily in young adults. The mortality rate is approximately 2%; however, it can exceed 20% in pregnant women in some regions in India. The causative agent, hepatitis E virus (HEV), has been isolated from several animal species, including pigs. HEV genotypes 3 and 4 have been isolated from both humans and animals, and are recognized as zoonotic pathogens. Seroprevalence studies in animals and humans indirectly suggest that HEV infections occur worldwide. The virus is primarily transmitted to humans via undercooked animal meats in developed countries. Moreover, transfusion- and transplantation-mediated HEV infections have recently been reported. This review summarizes the general characteristics of hepatitis E, HEV infection status in animals and humans, the zoonotic transmission modes of HEV, and HEV vaccine development status.  相似文献   
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10.
The effects of electroacupuncture (EA) on intraocular pressure (IOP) and hemodynamic parameters were evaluated in isoflurane anesthetized 10 (5 males, 5 females) normal mongrel dogs (8.1-9.8 kg, 6-8 years old). After determination of baseline IOP and hemodynamic parameters (cardiac index, systolic arterial pressure, diastolic arterial pressure, heart rate and systemic vascular resistance index), EA was applied at 3 acupoints (LI-4, LIV-3 and GB-37) for 20 min. After the EA treatment, IOP was significantly decreased in the both eyes (p<0.05). However, there were not significant differences in hemodynamic parameters between those of before and after EA treatment. From these results, the EA treatment at LI-4, LIV-3 and GB-37 would be considered one of the valuable methods for the IOP treatment in dogs.  相似文献   
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