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采用2种方法制备大鳞副泥鳅整体和分离的骨骼标本,记录观测结果并详细叙述骨骼系统的结构。结果表明:大鳞副泥鳅具发达的鼻区骨骼,眼区骨骼退化,具腹肋。腰带仅有一对无名骨组成。  相似文献   
124.
仔猪骨骼肌注射pGRF基因质粒的促生长及代谢调控效应研究   总被引:11,自引:2,他引:9  
给体重约 5 0kg的长白×太湖仔猪以 0 2 5、0 5、1 0、2 0mg剂量半腱肌部位注射 pGRF基因的表达质粒 ,5~ 10kg阶段终体重分别比 0mg组增加 4%、17%、2 0 %和 16 % ,日增重增加 8%、37%、43%和 36 % ,采食量提高 17%、2 7%、2 3 %和 11% ;耗料增重比 ,0 5mg组、1 0mg组及 2 0mg组分别比 0mg组降低 8%、14%和 18%。1 0mgpGRF基因质粒使血液中生长激素释放因子 (GRF)比对照组升高 1 6倍 (P <0 0 5 )、生长激素 (GH)升高2 5倍 (P <0 0 1)、类胰岛素生长因子 (IGF Ⅰ )升高 2 3倍 (P <0 0 1) ,血液中尿素浓度降低 2 0 % (P <0 0 5 ) ,血液中甘油三酯浓度 (TG)明显下降 (P <0 0 5 )。试验研究还证明生长抑素 (SS)分泌的增加是限制 pGRF基因质粒高用量时正效应发挥的重要因素 ,1mg为 5~ 10kg阶段仔猪注射 pGRF基因质粒的适宜剂量。  相似文献   
125.
An 8-month-old miniature horse filly was presented for evaluation of severe rotational and angular limb deformities of the thoracic and pelvic limbs. On radiographic examination, complete ulnas and fibulas were identified. These findings are consistent with a condition previously described as a form of atavism. The term atavism is used to describe the reappearance of a trait or character that was seen in all earlier evolutionary specimens of a particular species, but has not been seen in recent ancestors. The atavistic traits of complete ulnas and fibulas have previously been described in Welsh and Shetland Ponies, all of which had severe rotational and angular limb deformities. In this horse, bilateral osteochondritis dissecans of the medial trochlear ridge of the talii were also identified. To the authors' knowledge, this is the first report of the atavistic traits of complete ulnas and fibulas seen in the miniature horse.  相似文献   
126.
Limb deformities were detected in 135 out of 885 ostrich chicks, giving a prevalence of 15.3%. Tibiotarsal rotation affected 73% of the chicks with limb deformities, whereas rolled toes accounted for 36%. The right leg was more often affected than the left leg. The incidence of limb deformities was highest in 2- to 3-week-old ostrich chicks. The incidence of limb deformities was highest at the beginning of the breeding season and lowest towards the end, when it was relatively warmer. The mean serum manganese and zinc levels in deformed ostrich chicks were higher than the levels reported for normal chicks.  相似文献   
127.
A 1-month-old alpaca cria presented with a 13 degree valgus deformity of the left metacarpophalangeal joint. The angular limb deformity was centered on the distal metacarpal physes. Transphyseal bridging of the physes was recommended. Two 2.7 mm cortical bone screws were placed either side of the distal metacarpal physes and a figure of eight wire was placed medially around the screw heads. The screws extended through the medial metacarpus into the axial cortex of the lateral metacarpus. Seven weeks after surgery the limb was straight and the screws and wire were removed. Transphyseal bridging of the distal metacarpal physes can be effectively used for the treatment of metacarpophalangeal valgus in crias with open physes.  相似文献   
128.
We have used a porcine model of spontaneous differential fetal growth to investigate the effects of fetal size on muscle development. We hypothesized that altered muscle development may occur in small fetuses as a consequence of modified expression of selected genes of the insulin-like growth factor system. We examined the development of the Longissimus muscle (m. Longissimus) in small fetuses and their average sized littermates. We collected small for gestational age fetuses and their average sized sibling on days 45, 65 and 100 of gestation (term is 113-116 days). Small fetuses had significantly lower body weight at all three stages of gestation (p<0.05) and significantly reduced secondary to primary muscle fibre ratio in m. Longissimus on day 100 (p<0.05) compared to their littermates. On day 65, the expression of insulin-like growth factor receptor 1 and insulin-like growth factor binding protein 3 were significantly higher (p<0.05) in m. Longissimus of the small fetuses compared with their average sized littermates. On day 100, the expression of insulin-like growth factor receptor 1 remained significantly higher (p=0.001), in addition to significantly higher levels of insulin-like growth factor receptor 2 and insulin-like growth factor binding protein 5 in the small fetuses (p<0.05). No difference in levels of myogenin was observed between the small and average sized littermates. In conclusion, we demonstrate that reduced fetal muscle development is associated with an increased expression of several genes of the insulin-like growth factor system in small fetuses in mid to late gestation.  相似文献   
129.
赵海涛  陈永祥  胡思玉  肖玲远  朱彬 《安徽农业科学》2011,39(22):13848-13853,13873
分别利用常规方法和透明骨法制备四川裂腹鱼和昆明裂腹鱼的骨骼标本,对这两种裂腹鱼的骨骼系统进行比较分析。结果表明,四川裂腹鱼与昆明裂腹鱼骨骼系统间的差异较小,可能是种间亲缘关系较近的缘故。这两种裂腹鱼在某些骨骼如齿骨、前颌骨、前鳃盖骨上表现出一些明显的差异,这些特征可以作为种间的鉴别特征。  相似文献   
130.
This study examined the influence of swimbladder inflation (SBI) failure on mortality (Experiment 1), lordotic deformity (Experiment 2) and growth (Experiment 1, 2) in Pacific bluefin tuna, Thunnus orientalis, postflexion larvae and juveniles by producing larvae lacking inflated swimbladders. Experiment 1 was conducted for postflexion larvae to juveniles (from 18 to 30 days‐post‐hatch; dph). Mortality was not significantly different between the fish with (WIS) and without (WOIS) inflated swimbladders. Standard length (SL) and body weight (BW) were significantly smaller in WOIS than WIS. Moreover, the SBI was found in WOIS after postflexion stage. In Experiment 2, two examination trials were conducted on SBI, vertebral deformity and growth for juvenile stage. Lordotic deformities were found neither in the WOIS nor in the WIS. Although SL and BW were significantly smaller in WOIS than WIS at 22 dph, after 37 dph no significant differences were found between them. The results of Experiment 1 and 2 indicate that SBI failure causes growth retardation until juveniles of 30 dph; however, it does not cause growth retardation in juveniles after 37 dph and mortality of postflexion larvae and juveniles. Moreover, SBI failure did not cause lordotic deformity in PBT differently from many other fish.  相似文献   
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