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The reason why cows carrying the mutation of complex vertebral malformation (CVM) show poor reproductive capability although they carry only one mutant allele is still not fully understood. Monitoring the progesterone profiles during oestrous cycle and early pregnancy in carrier cows might help explain their lowered reproductive capability. Progesterone concentration was measured in 19 CVM carrier cows and 21 control cows during oestrous cycle and early pregnancy. Milk samples were collected from all cows starting on the day of artificial insemination until day 45 post‐AI. Progesterone was measured in skim milk using enzyme‐linked immunosorbent assay (ELISA). Progesterone concentration was significantly reduced on day 7 (p < 0.05) and day 9 (p < 0.01) post‐insemination in conceived CVM carrier cows when compared with that in control conceived cows. The mean progesterone concentration during early pregnancy was significantly lower (p < 0.05) in conceived cows with CVM than that of control cows in the same period. However, the mean progesterone concentration did not differ significantly (p = 0.072) in CVM cows that showed fertilization failure or embryonic death than that of control cows. Additionally, of 13 conceived control cows, eight cows (61.5%) showed normal luteal function. In contrast, of nine conceived CVM cows, only four cows (44.4%) showed normal luteal function. The conception rate was 47.4% in CVM carrier cows and 61.9% in control cows, but this difference did not reach significance. In conclusion, progesterone concentration might be lowered during early pregnancy in conceived CVM cows compared with that in control cows.  相似文献   
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The objective was to estimate—according to the French feeding system—the nutritive value of three tropical grasses (Eragrostis olivacea, Setaria sphacelata and Tripsacum laxum) used in traditional small farms of Burundi. Dry matter (DM) yield was monitored on anti-erosive hedges or on small fields in 60 small farms for eight consecutive years. DM intake and digestibility values were measured on seven steers or seven male sheep. Degradability values were determined on three sheep. S. sphacelata exhibited higher DM yield (t ha−1), energy (UF, kg−1 DM) and protein (PDI, g kg−1 DM) values (17.3, 0.73 and 68, respectively) than T. laxum (9.11, 0.64 and 47) and E. olivacea (not determined, 0.46 and 42). The UF and PDI intakes of these grass species were able to meet only 51% to 92% of the energy and 59% to 133% of the protein requirements for maintenance of the experimental animals.  相似文献   
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 【目的】青花菜的抗癌功能主要与4-甲基亚磺酰丁基硫苷的降解产物萝卜硫素有关,通过测定不同青花菜材料花球、茎和叶片中两者的含量并分析两者含量间的相关性,为青花菜高营养品质育种提供理论依据。【方法】采用反相高效液相色谱法,对24个不同青花菜材料花球、茎和叶片中4-甲基亚磺酰丁基硫苷含量,及其中的10份材料花球、茎和叶片中萝卜硫素含量进行测定和分析。【结果】青花菜不同基因型间以及不同器官间4-甲基亚磺酰丁基硫苷和萝卜硫素含量差异均极显著,4-甲基亚磺酰丁基硫苷和萝卜硫素含量均为花球含量最高,其次为茎,叶片含量最低;不同材料花球中4-甲基亚磺酰丁基硫苷平均含量分别为茎和叶片的4.4和13.97倍,萝卜硫素平均含量分别为茎和叶片的4和8.7倍,而有的基因型材料茎和叶片中4-甲基亚磺酰丁基硫苷的含量较高,约为花球中的50%;参试的10个不同基因型材料的花球、茎和叶片中的萝卜硫素含量与其前体4-甲基亚磺酰丁基硫苷含量间相关系数分别为0.9886**,0.9994**,0.9935**。【结论】不同青花菜材料间不同器官中4-甲基亚磺酰丁基硫苷含量存在显著差异;在青花菜萝卜硫素开发应用中,可选择其前体4-甲基亚磺酰丁基硫苷作为筛选指标,并可筛选茎和叶中4-甲基亚磺酰丁基硫苷含量较高的材料作为提取萝卜硫素的原料。  相似文献   
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ABSTRACT: Cyprinid herpesvirus 3 (CyHV-3), also known as Koi herpesvirus, is the etiological agent of a mortal disease in common and koi carp. Recently, we investigated the entry of CyHV-3 in carp using bioluminescence imaging and a CyHV-3 recombinant strain expressing luciferase (LUC). We demonstrated that the skin is the major portal of entry after inoculation of carp by immersion in water containing CyHV-3. While this model of infection mimics some natural conditions in which infection takes place, other epidemiological conditions could favour entry of virus through the digestive tract. Here, we investigated whether ingestion of infectious materials mediates CyHV-3 entry through the digestive tract. Carp were fed with materials contaminated with the CyHV-3 LUC recombinant (oral contamination) or immersed in water containing the virus (contamination by immersion). Bioluminescence imaging analyses performed at different times post-infection led to the following observations: (i) the pharyngeal periodontal mucosa is the major portal of entry after oral contamination, while the skin is the major portal of entry after contamination by immersion. (ii) Both modes of inoculation led to the spreading of the infection to the various organs tested. However, the timing and the sequence in which some of the organs turned positive were different between the two modes of inoculation. Finally, we compared the disease induced by the two inoculation modes. They led to comparable clinical signs and mortality rate. The results of the present study suggest that, based on epidemiological conditions, CyHV-3 can enter carp either by skin or periodontal pharyngeal mucosal infection.  相似文献   
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Objective-To investigate the hemostatic response to surgery and compare the response for ovariohysterectomy with that for ovariectomy and to evaluate the usefulness of thromboelastography on plasma samples. Animals-42 female dogs. Procedures-Dogs were assigned to undergo ovariohysterectomy or ovariectomy. Blood samples were collected immediately before and 1, 6, and 24 hours after surgery and stored at -80°C for subsequent analysis. Plasma samples were subjected to thromboelastography after thawing. In addition, coagulation variables were measured, including concentrations of von Willebrand factor antigen, fibrinogen, antithrombin, and protein C; activity of factor VIII; activated partial thromboplastin time; prothrombin time; and thrombin time. The fibrinolytic response was assessed via concentrations of D-dimer, plasminogen, and α-2-antiplasmin (plasmin inhibitor). Results-Substantial hemostatic and fibrinolytic activation was evident after surgery in both groups, as characterized by significantly increased global clot strength and an overall hypercoagulable state at 4 hours after surgery in addition to decreases in von Willebrand factor antigen and factor VIII concentrations and shortened prothrombin and thrombin times. The dogs also typically had activation of the fibrinolytic system, as evidenced by increased postoperative concentrations of D-dimer, plasminogen, and plasmin inhibitor. Differences between the 2 groups could not be detected for any variables. Conclusions and Clinical Relevance-Elective surgery with limited tissue trauma induced hemostatic activation in dogs, which led to hypercoagulability after surgery. A difference between the ovariohysterectomy and ovariectomy groups was not detected. Thromboelastography can be used on plasma samples and may be useful for evaluating patterns over time.  相似文献   
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