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1.
Foot-and-mouth disease virus typing by complement fixation and enzyme-linked immunosorbent assay using monovalent and polyvalent antisera. 总被引:1,自引:0,他引:1
A Alonso M A Martins M da P Gomes R Allende M S S?ndahl 《Journal of veterinary diagnostic investigation》1992,4(3):249-253
An indirect "sandwich" enzyme-linked immunosorbent assay (ELISA) using polyvalent and monovalent antisera was compared with the 50% complement fixation (CF50) test for the detection of foot-and-mouth disease (FMD) O, A, and C virus types. ELISA was more sensitive than CF50 tests when polyvalent antisera were used for detecting the 3 types of virus in epithelial samples, whereas ELISA using monovalent antisera was the least sensitive technique. The ELISA performed with polyvalent antisera was 9 times more sensitive for detecting FMD virus than that with monovalent antisera. However, viral isolation in cell culture was the most sensitive detection system. The combined use of ELISA with polyvalent antisera and cell culture inoculations was the most effective procedure for identifying FMD virus in epithelial samples from the field. 相似文献
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Nwaodu Chibuzo Hope Okoro Victor Mela Obinna Uchegbu Martins Chigozie Mbajiorgu Christian Anayochukwu 《Tropical animal health and production》2018,50(4):851-856
Tropical Animal Health and Production - A study was conducted to determine the effects of varied brooding regimes on the performance of small bronze turkey poults and their grow-outs. One hundred... 相似文献
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Melatonin reduces apoptotic cells,SOD2 and HSPB1 and improves the in vitro production and quality of bovine blastocysts
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TC Marques EC da Silva Santos TO Diesel LO Leme CF Martins MAN Dode BG Alves FPH Costa EB de Oliveira ML Gambarini 《Reproduction in domestic animals》2018,53(1):226-236
Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM + 10?7, IVM + 10?9, IVM + 10?11) and culture media (Experiment 2; Control, IVC + 10?7, IVC + 10?9, IVC + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM + 10?9, IVC + 10?9, IVM /IVC + 10?9). In Experiment 1, maturated oocytes from Control and IVM + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC + 10?7 (43.5%; 56.7%) and IVC + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM + 10?9. Reactive oxygen species production was greater in the IVM /IVC + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality. 相似文献
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Isabel Oliveira Cosentino Mario Felipe Alvarez Balaro Felipe Seabra Cardoso Leal Lucas de Figueiredo Cardoso Barbosa Fernanda Martins Gonçalves Gabriel Feliciano Felizardo Marina Monteiro Netto Felipe Zandonadi Brandão 《Reproduction in domestic animals》2020,55(11):1655-1659
This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (GNPSP: Group of non-pregnant does with second sponge: n = 8; GNPNSP: Group of non-pregnant does without second sponge: n = 6; GPSP: Group of pregnant does with second sponge: n = 5; GPNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (GNPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. GNPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or GPSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. GPNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle. 相似文献
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Lauren G Chukrallah Aditi Badrinath Kelly Seltzer Elizabeth M Snyder 《Journal of animal science》2021,99(3)
Ruminants are major producers of meat and milk, thus managing their reproductive potential is a key element in cost-effective, safe, and efficient food production. Of particular concern, defects in male germ cells and female germ cells may lead to significantly reduced live births relative to fertilization. However, the underlying molecular drivers of these defects are unclear. Small noncoding RNAs, such as piRNAs and miRNAs, are known to be important regulators of germ-cell physiology in mouse (the best-studied mammalian model organism) and emerging evidence suggests that this is also the case in a range of ruminant species, in particular bovine. Similarities exist between mouse and bovids, especially in the case of meiotic and postmeiotic male germ cells. However, fundamental differences in small RNA abundance and metabolism between these species have been observed in the female germ cell, differences that likely have profound impacts on their physiology. Further, parentally derived small noncoding RNAs are known to influence early embryos and significant species-specific differences in germ-cell born small noncoding RNAs have been observed. These findings demonstrate the mouse to be an imperfect model for understanding germ-cell small noncoding RNA biology in ruminants and highlight the need to increase research efforts in this underappreciated aspect of animal reproduction. 相似文献
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M. Manou J. Milgram P. Kelly S. Hoey K. Kenny S. Warde B. Kirby 《The Journal of small animal practice》2021,62(10):924-928
A 7-year-old male neutered domestic shorthair outdoor cat was referred for chronic left forelimb lameness, which had been treated with intra-articular injections of triamcinolone acetonide. A soft tissue swelling around the elbow joint, extending from the distal humerus to the proximal ulna, was surgically explored and biopsy samples obtained. Mycobacterium bovis was cultured from samples from the soft tissue and bone. The mycobacteria from the media were killed and the DNA extracted and tested on a multiplex real-time PCR for the absence of specific genes and the presence of mycobacterial genus markers. The PCR revealed bacillus Calmette-Guérin Danish Strain 1331; this was also isolated from the prescapular lymph node, muscle and bone, obtained at post mortem examination. Badgers had been vaccinated with the bacillus Calmette-Guérin vaccine SSI (Statens Serum Institute) in the area where the cat lived, in the spring and autumn of the previous year. To the authors' knowledge, this is the first report of infection with M. bovis bacillus Calmette-Guérin Danish Strain 1331 in a domestic cat, potentially associated with annual vaccination of badgers in the proximity of the cat's home. 相似文献