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101.
本研究利用ISSR分子标记技术对内蒙古6个群落野生华北驼绒藜种群的遗传多样性和遗传变异进行了分析,结果表明,内蒙古不同种群野生华北驼绒藜种水平遗传多样性较高,多态位点百分率(PPB)达到98.05%,Nei’s基因多样性指数(h)和Shannon多样性指数(I)分别为0.298 4和0.455 7;依据PPB、h和I估计的各种群内平均遗传多样性的变化趋势一致,依次为PA>PB>PD>PC>PE>PF。华北驼绒藜遗传变异主要存在于种群内。种群间的基因流(Nm)为4.333 2,大于1。根据聚类分析,大致可以将6个群落华北驼绒藜种群分为荒漠化草原种群和典型草原种群。生境片断化目前尚不足以导致华北驼绒藜特定基因丢失,发生遗传漂变的可能性很小。 相似文献
102.
将狂犬病病毒糖蛋白cDNA BglⅡ(1.67kb)片段正向插入pMT010/A^+BamHⅠ切点,构建重组质粒pMT010/A^+-Rgp,用EcoRⅠ+SalⅠ对pMT010/A^+-Rgp进行双酶切后,回收含有狂犬病病毒糖蛋白cDNA和绵羊MT启动子的2.76kb片段,通过显微注射技术将该片段注入小鼠单细胞受精卵雄前核内,在进行胚胎移植后,获得44只小鼠,经PCR、Southern杂交及原位 相似文献
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Chaleow Salakij Jarernsak Salakij Kreangsak Prihirunkit Nual‐Anong Narkkong Decha Pitakkingthong 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(2):193-198
Background: The Leopard Cat (Prionailurus bengalensis) is the most frequently encountered wild cat in most of Southeast Asia. Limited hematologic investigation exists for this species. Objectives: The objectives of this study were to assess routine hematologic measurements and parameters and characterize the morphology, cytochemical staining, and ultrastructural features of blood cells in Leopard Cats. Methods: Blood samples were collected from 12 adult healthy captive Leopard Cats (7 males and 5 females). Complete blood counts were performed using an automated hematology analyzer and manual differential counts. Cytochemical staining (Sudan black B [SBB], peroxidase [PO], periodic acid‐Schiff [PAS], α‐naphthyl acetate esterase [ANAE], and β‐glucuronidase [BG]) and scanning and transmission electron microscopy were performed using standard methods. Results: Median (range) hematologic results were as follows: PCV 0.46 L/L (0.30–0.55 L/L), hemoglobin 136.5 g/L (100–183 g/L), WBC 9.0 × 109/L (6.9–15.2 × 109/L), band neutrophils 0.07 × 109/L (0–0.30 × 109/L), segmented neutrophils 2.9 × 109/L (1.2–6.34 × 109/L), lymphocytes 5.3 × 109/L (2.7–8.1 × 109/L), eosinophils 0.14 × 109/L (0–0.73 × 109/L), basophils 0/L (0–0.22 × 109/L), and monocytes 0.08 × 109/L (0–0.30 × 109/L). Neutrophils stained strongly positive for SBB, PO, and PAS; lymphocytes had fine granular positivity for ANAE and BG; monocytes were weakly positive for ANAE and BG; and basophils were strongly positive for BG. Ultrastructurally, eosinophils contained many large rod‐shaped granules with prominent crystalloid core structures, ribosomes, and mitochondria. Basophils contained many round to oval specific granules with homogeneous contents. Low number of basophils contained a few small vacuoles that usually were not detected by light microscopy. Conclusion: These findings will facilitate interpretation of hematologic results for future investigative and diagnostic studies of this species. 相似文献
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B Grimard B Marquant‐Leguienne D Remy C Richard F Nuttinck P Humblot AA Ponter 《Reproduction in domestic animals》2013,48(2):183-194
The aim of this study was to determine whether postpartum variations of plasma IGF‐1 and IGFBP concentrations, oocyte production and quality were related to parity and subsequent conception rate in Holstein dairy cows. Holstein dairy cows [10 primiparous (PP) and 22 multiparous (MP)] were allotted in six batches and sampled once weekly between calving and oestrous synchronization treatment started at 71.2 ± 2.0 days postpartum. During the 3 weeks before treatment, ovum pick‐up (OPU) was performed twice weekly. Oocytes were scored on a 4‐point scale, and oocytes from OPU1, 3 and 5 were fertilized in vitro. Seventeen cows became pregnant after first and second AI and were considered as fertile (F), while the others were considered to be subfertile (SF). Logistic regression was carried out to investigate the relationships between repeated measurements and fertility including parity and batch effects in the models. Likelihood of fertility significantly increased when plasma urea and IGFBP‐3 concentrations decreased and was higher in PP compared with MP cows. There was a trend for fertility to increase when plasma IGF‐1 concentrations increased (p = 0.07). In vitro cleavage and development rates were similar between SF and F cows (46.4% and 28.3% in SF vs 55.0% and 22.1% in F). Parity had an effect on plasma IGF‐1 concentrations (PP: 61.65 ± 2.67 vs MP: 41.63 ± 5.81 ng/ml, p < 0.001), mean number of follicles aspirated per session (PP: 5.7 ± 1.3 vs MP: 9.5 ± 0.8, p < 0.05) and fertility (PP: 8/10 = 80% vs MP: 9/22 = 41%, p < 0.05) but not on the number of oocytes recovered per session nor their quality. In conclusion, postpartum plasma urea and IGFBP‐3 concentrations, but not oocyte production and quality before breeding, were related to subsequent conception rate in our experimental design. Parity had a significant effect on energy status, follicular growth and fertility and needs to be considered when investigating relationships between nutrition and reproduction. 相似文献
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Lysophosphatidic Acid Synthesis and its Receptors’ Expression in the Bovine Oviduct During the Oestrous Cycle 下载免费PDF全文
E Sinderewicz K Grycmacher D Boruszewska I Kowalczyk‐Zięba Y Yamamoto Y Yoshimoto I Woclawek‐Potocka 《Reproduction in domestic animals》2016,51(4):541-549
Lysophosphatidic acid (LPA) is a naturally occurring simple phospholipid which in the bovine reproductive system can be produced in the endometrium, corpus luteum, ovarian follicle and embryo. In this study, we examined the possibility that LPA receptors are expressed, and LPA synthesized, in the bovine oviduct. We found that the concentration of LPA was highest in infundibulum in the follicular phase of the oestrous cycle and was relatively high during the early‐luteal phase in all examined parts of the oviduct. We also documented that LPA synthesis engages both available pathways for LPA production. The autotaxin (ATX) protein expression was significantly higher in the infundibulum compared to the isthmus during the follicular phase of the oestrous cycle. During the early‐luteal phase of the oestrous cycle, ATX and phospholipase A2 (PLA2) protein expression was highest in ampulla, although the expression of LPARs was not as dynamic as LPA concentration in the oviduct tissue, and we presume that in the bovine oviduct, the most abundantly expressed receptor is LPAR2. In conclusion, our results indicate that the bovine oviduct is a site of LPA synthesis and a target for LPA action in the bovine reproductive tract. We documented that LPAR2 is the most abundantly expressed in the bovine oviduct. We hypothesize that in the bovine oviduct, LPA may be involved in the transport of gametes, fertilization and cellular signalling between the oviduct and cumulus–oocyte complex. 相似文献
110.
An experiment was conducted to scientifically identify the appropriate feed for Gansu Alpine Fine Wool ewes in order to change the animals' breeding mode, which currently can only be mated at the age of 2.5 years due to insufficient nutritional supply. The experiment selected 48 12-month-old ewes and randomly divided them into group a (Diet 1), group b (Diet 2), group c (Diet 3), and a control group with no supplementary feeding. The feed test was run for 90 days. The rumen pH of groups a and b were very significantly higher (P<0.01) or group c significantly lower (P<0.05) than control group. The rumen ammonia nitrogen, protein nitrogen and total nitrogen of groups a, b and c were all higher than control group (P<0.01). The total volatile fatty acids of group a and b were all higher than the control group (P<0.01), group b significantly higher than group c (P<0.05). The molar ratio of acetic acid and propionic acid in group a was very significantly higher than control group (P<0.01), group b and c were significantly higher than control group (P<0.05). The molar ratio of butyric acid in group a was very significantly higher than group c (P<0.01). The ratio of acetic acid and propionic acid in group b was significantly lower than control group (P<0.05). The number of several rumen fiber-degrading bacteria and protozoa in groups a, b and c were very significantly (P<0.01) or significantly (P<0.05) higher than the control. In conclusion, this study shows that supplementary feeding can positively affect the rumen metabolic parameters and the number of several rumen microorganisms in Gansu Alpine Fine Wool ewes. In general, the effects of Diet 1 were the strongest, while Diet 2 also produced notable improvements. © 2018, Editorial Office of Acta Prataculturae Sinica. All rights reserved. 相似文献