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1.
本试验旨在研究高饲养密度条件下饲粮中添加硫辛酸(LA)对肉鸡血清指标、行为及骨骼发育的影响。试验选取健康状况良好、体重相近的1530只21日龄爱拔益加(AA)肉鸡,随机分成3组,即常规饲养密度组(ND组,15只/m^2,饲喂基础饲粮)、高饲养密度组(HD组,18只/m^2,饲喂基础饲粮)和高饲养密度+LA组(HD+LA组,18只/m^2,在基础饲粮在添加300 mg/kg LA),每组6个重复。试验期为3周。结果表明:1)与ND组相比,HD组肉鸡血清钙含量和碱性磷酸酶(ALP)活性显著下降(P<0.05),血清皮质酮(CORT)含量以及还原型辅酶Ⅱ氧化酶(NOX)和髓过氧化物酶(MPO)活性显著上升(P<0.05)。2)与ND组相比,HD组肉鸡行走、梳翅、采食频次与时间占比显著降低(P<0.05),而饮水频次以及饮水和趴卧时间占比显著升高(P<0.05)。3)与ND组相比,高饲养密度显著降低肉鸡胫骨与股骨直径、重量、密度、强度以及钙、磷、灰分和矿物盐含量(P<0.05)。4)与HD组相比,HD+LA组肉鸡血清钙含量和ALP活性显著升高(P<0.05),血清CORT含量以及NOX和MPO活性显著下降(P<0.05);采食频次和时间占比显著增加(P<0.05),饮水频次和趴卧时间占比显著降低(P<0.05);胫骨质量以及钙、磷含量与股骨密度、强度和钙含量显著上升(P<0.05)。综上所述,高饲养密度致使肉鸡发生氧化应激,改变了肉鸡行为,并使肉鸡骨骼质量下降,而饲粮中添加LA能在一定程度上缓解高饲养密度对肉鸡造成的损伤。  相似文献   
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Seriolella violacea, a new species to be potentially farmed in Chile and Peru, has shown cranial malformations during farming that could adversely affect its commercial development. This study seeks to generate early knowledge of the osteological development and type of cranial abnormalities that this species presents under culture conditions. Larvae from wild caught broodstock were reared from 1 to 60 days post hatching (DPH) (4.8 ± 0.1 mm TL and 11.8 ± 1.0 mm TL respectively). Larvae samples were collected throughout the experimental trial for recording cranial osteological development and abnormalities in cartilage and bone. At 5.7 ± 0.1 mm TL, coraco‐scapular, sclerotic, ethmoid plate and quadrate cartilages were present. At 8.0 ± 0.6 mm TL, early ossification was observed in the jaw, premaxilla and maxilla. At 11.8 ± 1.0 mm TL, the branchiostegal rays, jaw, maxilla and opercular complex were ossified. The first cartilaginous structures observed were the Meckel's cartilage, the branchial arches and the suspensory ligament. The first cranial malformations were detected at 5.7 ± 0.1 mm TL, coinciding with mouth opening. The most frequent malformations were a curvature of the lower jaw (23.1%), abnormal separation between branchial arches and the Meckel's cartilage (19.4%) and bulging jaws (15.7%).  相似文献   
4.
A 70‐day growth trail was conducted to investigate the effects of inclusion of high levels of meat and bone meal (MBM) and protein concentrate (PC) on growth, digestibility and economic performances of climbing perch, Anabas testudineus. Four isonitrogenous diets were formulated by lowering the level of dietary fishmeal protein at 0 (D1, control), 70 (D2), 85 (D3) and 100% (D4) with a mixture of MBM and PC protein (1:1). Triplicate groups of 300 fish (mean weight of 0.80 g) stocked in each 40 m2 pond and fed the respective test diets. A digestibility trial was conducted after the growth trial in indoor glass aquarium. The result showed that growth parameters were significantly decreased (P < 0.05) with fishmeal replacement levels. However, significant differences were not found in feed conversion ratio and survival of fish. No difference was also found in protein efficiency ratio among D1, D2 and D3. Similar to growth parameters, total fish production was highest in D1, intermediate in D2 and D3; and lowest in D4. Apparent digestibility coefficients of dry matter, protein and lipid were highest (P < 0.05) in D1 and lowest in D4. The economic analysis revealed that the benefit cost ratio was ranked by D3 (1.81), D2 (1.71), D1 (1.66) and D4 (1.46) respectively. Upon considering the overall performances and unavailability of finite protein sources, it can be concluded that 70–85% fishmeal could be replaced with a mixture of MBM and PC (1:1) in practical diets for climbing perch.  相似文献   
5.
A 3-year-old Standardbred gelding (Case 1) and a 2-year-old Thoroughbred gelding (Case 2) were referred for surgical evaluation of a left radial carpal bone (RCB) fracture, sustained during training. Clinical findings at the time of initial examination included a palpable effusion within the left middle carpal joint in both horses and marked signs of pain and reduced range of motion on flexion of the affected carpus. In both horses, the RCB fracture was evident on the following radiographic views of the carpus: dorsolateral–palmaromedial oblique (30° off lateromedial) and flexed lateromedial. An additional loose wedge-shaped osteochondral fragment at the proximal articular surface of the RCB could be seen in Case 2. Both horses underwent surgical reduction and repair of the fracture between 1 and 2 days following the initial injury, which consisted of arthroscopic removal of any intra-articular osteochondral fragments, and arthroscopic assisted-interfragmentary compression via a standard dorsomedial and dorsolateral approach to the antebrachiocarpal joint (ACJ) and middle carpal joints (MCJ). The two horses returned to function as racehorses, 6 months (Case 1) and 16 months (Case 2) after surgery. The RCB is a relatively uncommon site for large carpal fractures in horses. The clinical presentation and findings from this report were similar to that of third carpal bone (C3) slab fractures, confirming that surgical repair is indicated in selected cases of RCB fractures.  相似文献   
6.
This experiment was conducted to investigate the effect of dietary calcium (Ca) or phosphorus (P) deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study, which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age. A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design, and fed the normal control and Ca- or P-deficient diets from 1 to 21 days of age. At 22 days of age, the broilers were further fed the normal control diet (0.90% Ca+0.35% non-phytate P (NPP)), the P-deficient diet (0.90% Ca+0.18% NPP), the Ca-deficient diet (0.30% Ca+0.35% NPP) or the Ca and P-deficient diet (0.30% Ca+0.18% NPP), respectively. The results showed that dietary Ca or P deficiency decreased (P<0.05) tibia bone mineral density (BMD), bone breaking strength (BBS), ash content, tibia ash Ca content and serum P content on days 28 and 42, but increased (P<0.05) tibia alkaline phosphatase (ALP) activity of broilers on day 42 compared with the control group. Furthermore, the broilers fed the P-deficient diet had the lowest (P<0.05) tibia BMD, BBS, ash content, serum P content and the highest (P<0.05) serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets. The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency, followed by dietary Ca deficiency or Ca and P-deficiency; dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.  相似文献   
7.
姜迪  姚剑  钱渊  杜林 《核农学报》2020,34(Z1):43-49
为探讨不同地域来源的明胶骨原料中碳、氮稳定同位素的分布特征及其相关性,本试验采用元素分析-稳定同位素比率质谱仪测定了广西、内蒙古和山东3个主产区的牛骨样品及当地牧草饲料样品中的13C和15N同位素组成,并结合线性回归讨论了牛骨样品中δ13C和δ15N值的相关性与牛食谱组成的关系。结果表明,广西地区骨样品中δ13C和δ15N值的相关性较好(R2=0.401 8),而内蒙古和山东地区骨样品中δ13C和δ15N值的相关性较差(R2<0.1),反映了3地牛食物的来源稳定性及主要成分存在明显差异,对各地牛食谱结构推测的结果与实际牧草饲料样品中δ13C和δ15N值的地区分布规律也较为一致。本研究初步揭示了明胶骨原料中碳、氮稳定同位素产生地域性差异的原因,不仅为动物生态学研究提供了有益信息,更为动物制品产地溯源研究提供了新思路。  相似文献   
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Campylorrhinus lateralis, also known as “wry nose,” is a congenital malformation that mainly affects Thoroughbreds. These horses have a unilateral deviation of the maxillae that may be to one side or the other side, and it causes airway obstruction and dental malocclusion. The choice of treatment is not necessarily operation; however, the treatment of choice, which aims to repair the maxillae deviation, is surgical to improve the horse’s respiratory condition and correct the dental occlusion. There are currently no reports describing the first surgical technique for such deformity described by Valdez et al. The present study describes the case of a 2-month-old foal of the Mangalarga Marchador breed that was diagnosed with wry nose. The foal presented with accentuated maxillae deviation to the right side, malocclusion of the incisor teeth, and respiratory noises. After diagnosis and physical examination, the foal was treated by surgical correction of the deviation. To correct the deviation, the bone distraction technique with unilateral osteotomy of the right maxillae and fixation of the external bone distractor was chosen. After 90 days, the bone distractor was removed; consequently, malocclusion of the incisors was greatly improved, and respiratory noises were eliminated.  相似文献   
10.
Congenital frontal osteoma has not been previously described in horses. This report records—for the first time—a congenital osteoma of the frontal bone in a 4-month-old Arabian filly. The filly had a frontal hard mass that was present at birth and then showed a slow and continuous growth. This mass appeared as a solitary, painless, oval dense tumor of compact bone, about 2 cm in diameter and 3 cm in length. The tumor was asymptomatic, and the skin over the mass was normal. Radiography revealed a well-defined oval, radio-dense mass projecting from the surface of the right frontal bone with no local invasion. The tumor had a broad-based attachment to frontal bone with normal frontal sinus. The mass caused disfigurement; therefore, it was removed at the owner’s request. The mass was diagnosed histopathologically as osteoma. The surgical excision of the osteoma was successful without any complications, and the filly adapted remarkably well after surgery. No recurrence was reported 20 months after the surgery. In conclusion, osteoma should be listed during the differential diagnosis of the congenital craniofacial masses in horses. Early diagnosis of the frontal osteoma guarantees a successful surgical treatment and consequently prevents the future complications.  相似文献   
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