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排序方式: 共有170条查询结果,搜索用时 15 毫秒
161.
Felipe Pratalli Martins Erick Candiota Souza Fernanda Coelho Simas Bernardes Marcelo Abidu-Figueiredo Carlos Benhur Kasper Paulo de Souza-Junior 《Anatomia, histologia, embryologia》2021,50(1):212-217
Anatomical variation in wild canids is rarely described. Altered shapes, uni- or bilaterally situated, were observed in ventral laminae of C6 and/or in C7 vertebral body of two fox species: Lycalopex gymnocercus and Cerdocyon thous. The specimens were young adults, collected dead on highways in southern Brazil. Deformities were considered anatomical variations because apparently there was no interference in function. The occurrence of such variations in two related species from the same area can suggest an environmental common cause rather than genetic issues. Future studies may deepen the understanding between cause and effect of these vertebral deformities in wild canids. 相似文献
162.
Oxidative stress is a major factor affecting animal health and production performance. This paper briefly introduced the signaling pathways(i.e. NF-κB signaling pathway, MAPK, AP-1 and PGC-1α) of oxidative stress and the main genes regulating the signals of oxidative stress in skeletal muscle, providing a theoretical basis for reducing oxidative stress damage. 相似文献
163.
164.
硬骨鱼类的骨骼肌可为其游泳运动提供动力。为认识不同游泳习性鱼类的骨骼肌肌纤维组织学特征,本研究选取3种具有不同游泳习性的鱼类:鲐(Scomber japonicus)、大黄鱼(Larimichthys crocea)和褐牙鲆(Paralichthys olivaceus),采用石蜡切片苏木精–伊红染色法和形态计量法,以形状、直径和密度作为评价指标,对其骨骼肌的快、慢肌纤维组织学特性进行表征,比较3种不同游泳习性鱼类的快、慢肌纤维组织学特征差异。组织学观察发现,3种类型鱼类的骨骼肌快、慢肌纤维横切面均呈不规则形状。营持续式游泳的鲐的快肌纤维呈多角状,慢肌纤维呈多边柱形;营延长式游泳的大黄鱼的快、慢肌纤维呈长椭圆形;营爆发式游泳的褐牙鲆的快、慢肌纤维呈扁椭圆形。形态计量结果显示,3种鱼类的快肌纤维直径均极显著大于其慢肌纤维(P<0.01)。大黄鱼的慢肌纤维直径在3种鱼类中最大,约为鲐的1.34倍、褐牙鲆的1.14倍;鲐的快肌纤维直径在3种鱼类中最大,约为大黄鱼的1.41倍、褐牙鲆的1.35倍。3种鱼类的快肌纤维密度均极显著小于其慢肌纤维(P< 0.01),其中,快肌纤维密度大小排序为褐牙鲆[(274.60±9.07)根/mm2]>大黄鱼[(205.43±12.63)根/mm2]>鲐[(118.92±10.74)根/mm2],慢肌纤维密度大小排序为鲐[(1 442.33±28.25)根/mm2]>褐牙鲆[(1 073.92±39.40)根/mm2]>大黄鱼[(945.74±19.53)根/mm2]。进一步分析发现,鱼类的肌纤维形状、直径和密度与鱼类的游泳习性密切相关。上述对不同游泳习性硬骨鱼类骨骼肌的肌纤维形状、直径和密度等组织学特征的描述与差异分析结果,可为进一步开展硬骨鱼骨骼肌的适应性进化和运动生理学研究提供基础性资料。 相似文献
165.
This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site‐specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics. 相似文献
166.
丝氨酸可通过内源性途径合成,在传统营养学上属于非必需氨基酸.在机体正常生理功能下,丝氨酸广泛参与嘌呤合成、一碳代谢、谷胱甘肽合成以及脂质合成等多个重要的机体代谢过程.此外,丝氨酸还对细胞增殖分化、氧化还原平衡、神经系统和免疫功能等具有调节作用.近期研究发现,丝氨酸有益于肠道健康,且可提高猪的生长性能.本文主要综述了丝氨... 相似文献
167.
P.G. FJELLDAL T. HANSEN O. BRECK R. SANDVIK R. WAAGBØ A. BERG & R. ØRNSRUD 《Aquaculture Nutrition》2009,15(4):366-378
An earlier study demonstrated that under‐yearling (0+) Atlantic salmon (Salmo salar L.) smolt had a lower vertebral mineral content and mechanical strength and higher prevalence of vertebral deformities than 1+ smolt during the early seawater (SW) phase. The present study aimed to examine if commercial extruded high‐energy diets need to be supplemented additional minerals for proper bone mineralization and prevention of bone deformities in fast growing 0 + smolts. We studied vertebral morphology with radiology, and bone mineral content and mechanical strength in 60 g 0+ smolt fed diets with a normal (NM) or elevated (HM) bone mineral (P and Ca) contents from SW transfer (week 0) until 10 times weight increase at week 17. Thereafter, both groups were fed a commercial diet until a mean slaughter weight of 4100 g after 57 week. There were no differences in body weight and length between the dietary groups during the study, while the condition factor differed significantly at the final sampling (NM 1.40; HM 1.29). The most common bone deformity observed was compressions in the tail region of the vertebral column. Lower incidences of vertebral deformities (percent individuals with one or more deformed vertebrae) was observed in the HM group in week 17 (HM 20%; NM 47%) and week 57 (HM 37%; NM 73%), also reflected by higher vertebral length/dorso‐ventral diameter ratio in weeks 17 (HM 0.99; MN 0.92) and 57 (HM 0.97; NM 0.88). The HM group had significantly higher vertebral mineral content (HM 550 g kg?1; NM 480 g kg?1) and mechanical strength (HM 9050 g mm?1; NM 4600 g mm?1) than the NM group after 8 week feeding. Plasma levels of Ca, P and D‐vitamin metabolites recorded in week 8 reflected changes in P homeostasis, but could not explain the preventive effect of the HM diet on development of bone deformities. The results suggest that elevated dietary mineral content during the early SW phase may reduce the prevalence of vertebral deformities in fast growing 0 + salmon smolts. 相似文献
168.
Velmurugu Puvanendran Colleen Calder-Crewe & Joseph A Brown 《Aquaculture Research》2009,40(14):1653-1660
The effects of different egg incubation densities on the incidences of vertebral deformities in Atlantic cod larvae were investigated. Cod eggs were incubated at four different densities, 3, 6, 12 and 48 mL eggs L−1 , of water. When all the eggs hatched, larvae were reared in 30 L glass aquaria. Larval samples were taken at 0, 14, 42 and 56 days post hatch (dph) for deformity analysis. Larval samples were stained using bone and cartilage staining methods to determine vertebral deformity. Incubation densities did not have any significant effects on vertebral deformities in Atlantic cod larvae. However, the incidence of larval vertebral deformity was high at hatch and decreased as the larvae grew older until 42 dph, indicating selective mortality of deformed larvae during this period. Larvae at 56 dph, however, showed an increase in the incidence of vertebral deformity, indicating a possible nutritional or prey-type effect. To our knowledge, no studies have documented the occurrence of variable patterns in vertebral deformities in cod at various developmental stages. Overall, our results suggest that broodstock husbandry, genetics and/or nutrition could play a major role in causing vertebral deformities in Atlantic cod at hatch; however, nutrition and prey type may play a major role during metamorphosis. 相似文献
169.
170.
本文旨在探讨VE缺乏对鲤骨骼肌损伤的形态学影响。在半纯合日粮中分别添加0、25、50和100 mg/kg的VE,投喂体重约60 g的鲤鱼20周。结果表明:鲤鱼摄入VE缺乏的饲料后,出现“瘦背症”、脊柱弯曲及以突眼、竖鳞和腹水为特征的渗出性素质样病变。病理剖解见体壁肌肉萎缩,特别是背部两侧肌肉萎缩变薄,其厚度仅为对照组的1/4~1/2,似刀刃状;体侧红肌纤维褪色变白,呈白肌肉外观。组织学变化主要表现为肌营养性不良,骨骼肌变性、坏死,淋巴细胞和单核细胞浸润,大量结缔组织增生,残存的肌纤维萎缩变细。超微结构上表现为骨骼肌细胞核膜间隙增宽,呈锯齿状,并发生局部或广泛性的断裂,核变形,电子密度降低;肌浆内糖原颗粒明显减少,线粒体肿胀,嵴断裂,甚至溶解呈空囊泡状,肌原纤维的横纹模糊不清或完全消失。结论:日粮中0、25和50 mg/kgVE水平会导致鲤出现VE缺乏症,其骨骼肌主要表现为变性、坏死、肌萎缩和炎症细胞浸润的肌营养性不良。 相似文献