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1.
Mouse pronuclear stage embryos with intact slit zona pellucida (manipulated) were cultured in vitro until the hatched blastocyst stage in simplex optimized medium with higher K+ concentration (KSOM) prepared with three different water types: tap, deionized reverse osmosis (D‐O) water and Milli‐Q system (M‐Q) water. The culture media were supplemented with or without protein and ethylenediaminetetraacetic acid (EDTA, disodium salt). The rates of hatched blastocysts were significantly affected (p < 0.01) by micromanipulation, protein supplement and water source. The water source has no influence (p > 0.05) on development in EDTA‐supplemented protein‐free culture media, whereas in EDTA‐ and protein‐free culture media, the water quality significantly (p < 0.001) affected the rates of development, with higher rates in media prepared with M‐Q water. The micromanipulated embryos showed higher sensitivity to the water quality (p < 0.01). It worth mentioning that the rates of hatched blastocysts in protein‐free culture media were very low (0–7.5%). Furthermore, the three different water types were analysed by measuring the electrical conductivity, inorganic ions, total organic carbon and endotoxins to evaluate the purity. M‐Q water showed the lowest levels of inorganic ion, total organic carbon and endotoxin concentrations. We concluded that manipulated mouse embryos are good system to evaluate the quality of water used in biological system. 相似文献
2.
Chicken anemia agent in the United States: isolation of the virus and detection of antibody in broiler breeder flocks 总被引:4,自引:0,他引:4
Chicken anemia agent (CAA) was isolated from broiler chickens in Texas with a blue wing or anemia dermatitis-like syndrome. Specific-pathogen-free chicks inoculated with field material developed anemia, and CAA was isolated in MDCC-MSB1 cells from bone marrow and lymphoid tissue from inoculated chicks. One isolate, designated EF88/78/276, was further characterized. Infectivity of EF88/78/276 was resistant to treatment with chloroform and with heat at 70 C for 5 minutes. EF88/78/276 was indistinguishable from the Cux-1 and Gifu-1 isolates of CAA by cross-neutralization tests. Almost all 1-day-old susceptible chicks inoculated intramuscularly with EF88/78/276 developed anemia, but contact-infected chicks did not. Antibody to CAA was detected in broiler breeder flocks from Texas, the Delmarva peninsula, and Alabama. 相似文献
3.
ACE inhibition in goats under fixed‐time artificial insemination protocol increases the pregnancy rate and twin births
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VP Fernandes Neto MNN Silva AS Costa D Kunkel AS Júnior LCS Feitosa MCS Muratori APR Costa 《Reproduction in domestic animals》2018,53(4):1006-1008
To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology. 相似文献
4.
Núñez A McNeilly F Perea A Sánchez-Cordón PJ Huerta B Allan G Carrasco L 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(5):255-258
Routine histopathological diagnosis of one representative 3-month-old pig from a group suffering from diarrhoea revealed a massive degree of parasitation by Cryptosporidium parvum, with a concomitant infection by porcine circovirus type 2 (PCV2), that was confirmed by immunohistochemical procedures. The areas of intestine where parasites were more numerous presented abundant PCV2 infected cells in mucosa and submucosa. The concurrence of C. parvum, a rare primary intestinal pathogen in post-weaning and growing pigs, and PCV2 infections suggest an increased susceptibility as a result of an immunosuppression state. 相似文献
5.
6.
Development of an enzyme-linked immunosorbent assay to detect serum antibody to chicken anemia agent 总被引:3,自引:0,他引:3
D Todd D P Mackie K A Mawhinney T J Connor F McNeilly M S McNulty 《Avian diseases》1990,34(2):359-363
An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to chicken anemia agent (CAA) has been developed. This test utilizes a CAA-specific mouse monoclonal antibody to selectively capture virus antigen. Chicken antibodies to CAA bind to the captured antigen and are detected with horseradish peroxidase-labeled anti-chicken immunoglobulin using a conventional indirect ELISA protocol. When 388 chicken sera from specific-pathogen-free and commercial flocks from the United Kingdom, West Germany, the United States and Australia were examined, 98.5% agreement was obtained between the results of the ELISA and the indirect immunofluorescence assay. This ELISA should have worldwide application in testing SPF and commercial chicken flocks for CAA antibodies. 相似文献
7.
OHO Eckhardt SMMK Martins ME Pinese FC Horta AC Rosseto MA Torres AFC De Andrade BBD Muro CT Marino PHM Rodrigues AS Moretti 《Reproduction in domestic animals》2014,49(6):964-969
The aim of this study was to evaluate the reproductive performance of three parities of gilts treated or not treated with gonadotropin to induce puberty. Sixty gilts received 600 IU of equine chorionic gonadotropin (eCG) followed by 2.5 mg of porcine luteinizing hormone (LH) 72 h later. Fifty‐nine other gilts were exposed only to a mature boar for 15 min twice daily. Artificial insemination (AI) was performed at 0, 12 and 24 h after the detection of oestrus, and gestation was confirmed by ultrasound after 35 days. Sows were inseminated at the first post‐weaning oestrus. The total numbers of piglets born, piglets born alive, stillborn, mummified foetuses, as well as pregnancy and farrowing rates were evaluated for each of the three parities. Culling rates, farrowing intervals and weaning‐to‐oestrous intervals (WEI) were also analysed. Mean age at puberty and oestrous manifestation were not significantly different between treatments (p = 0.0639; 179.20 ± 17.52 compared with 173.96 ± 16.94, 91.66% compared with 94.92%) across the experimental period. However, females that underwent puberty induction showed modest increases both in the number of total pigs born and in the number of piglets born alive. In conclusion, puberty induction through exogenous gonadotropin administration in field conditions did not induce a more concentrated first oestrous manifestation, but trended to a modest increase in the number of pigs born alive in the first parity and a reduced culling rate during the first gestation. 相似文献
8.
Summary Co-adaptation between neighbouring genotypes of Lolium perenne was examined in a pot experiment over an 18 month period. Competitive interactions in pure and mixed stands were examined using 9 genotype pairs (established as neighbours from electrophoresis data), 7 from a 10 year-old, and 2 from a 40+ year-old pasture. Combinations of each pair of neighbours grown together, and each grown with 5 randomly chosen alien (non-neighbour) genotypes sampled from the same pastures were also assessed. Seven harvests of green matter produced above 20 mm were made, and 50–135 kg N ha-1 was administered after each harvest. Data for dry weight at each harvest for pure and mixed stands, and Relative Yield Totals (RYT) were obtained for neighbours and aliens in each treatment.In 6 of the 9 pairs of neighbours grown as pure stands, the yields of neighbours did not differ significantly at the final harvest. In 8 of the 9 pairs grown as mixtures of pairs of neighbours, the yield of one of the neighbours was significantly reduced and one neighbour had been eliminated. Over the last 5 harvests, yields from (alien + neighbour) mixtures had the greatest dry matter yields. No suppression of one component by the other was recorded for this (alien + neighbour) combination.Based upon RYT estimates, neighbours did not yield more when grown together than when grown separately with aliens. There was no relationship between original genotype size in their fields of origin and dry matter yield in this experiment.This experiment provides no evidence for he evolution of co-adaptation between surviving neighbours in the two pastures from which these individuals were sampled. The genotypic architecture of pasture would seem to be the product of random and/or competitive exclusion of individual genotypes, rather than the evolution of co-adapted groups of individuals through time. The consequences of extreme depletion of genetic variation in the first two years after establishment, the very low rates of seedling establishment in established pastures, and the impact of the grazing animal would suggest that there is little likelihood of or potential for, co-adaptation evolving between neighbours. 相似文献
9.
Summary Thirty five individuals from each of nine perennial ryegrass populations were sampled from set-stocked and zero-grazed swards and from an old permanent pasture. The swards were 6, 18, 30 months and 11 years old when sampled. The permanent pasture was at least 40 years old.Dry matter digestibility (DMD) and organic matter digestibility (OMD) were determined for green leaf material harvested 4 days after ear emergence. Significant differences were found between the populations, but genotypic differences were found only for OMD. The largest proportion of the total variation was due to differences between blocks. In the zero-grazed populations, DMD and OMD declined significantly with increasing sward age. This was not found for the set-stocked swards. Two sets of pair crosses, from which mid-parent, progeny regressions could be determined, were carried out.The regressions of offspring on mid-parent for set-stocked and zero-grazed swards were used to assess the presence of additive genetic variation and to estimate narrow sense heritability of DMD. The coefficients of correlation, 0.122 and 0.226 respectively, were non-significant, indicating an absence of additive genetic variation. 相似文献
10.
Porcine circovirus 2 infection in swine foetuses inoculated at different stages of gestation 总被引:11,自引:0,他引:11
The ability of porcine circovirus 2 (PCV2) to replicate and cause pathologic abnormalities in foetuses at selected time points of gestation was examined in this study. Two foetuses were inoculated in utero in each of two sows at 57, 75 and 92 days of gestation, respectively, with PCV2 (1121). The remaining foetuses were left uninoculated to assess whether intra-uterine spread occurred. Twenty-one days after inoculation, the foetuses were collected and examined for gross lesions and for virus and infected cells in different organs. Serum samples from all foetuses were tested for PCV2 antibodies. Virus replication was detected in all inoculated foetuses. Spread to non-inoculated foetuses did not occur. Virus replication was significantly higher in foetuses inoculated at 57 days compared to that inoculated at 75 and 92 days. The heart contained the highest virus titre and highest number of viral antigen positive cells. Gross lesions were observed only in foetuses inoculated at 57 days of age. PCV2 antibodies were detected only in foetuses inoculated at 75 and 92 days. This study shows the ability of PCV2 to replicate in foetuses at different stages of gestation and to cause pathologic abnormalities in foetuses inoculated at 57 gestational days. 相似文献