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241.
Leptin and adiponectin play important roles in carbohydrate and lipid metabolism in different species. Information is limited on the effects of diet, weight gain, and fat mass on their concentrations in cats. This study compared fasting and postprandial blood leptin and total adiponectin concentrations before and after 8 wk of ad libitum feeding to promote weight gain in adult cats (n = 32) fed either a low-carbohydrate, high-protein (23% and 47% ME) or a high-carbohydrate, low-protein (51% and 21% ME) diet. There were significant effects of total, abdominal, and nonabdominal fat mass, but not diet or body weight, on mean 24-h and peak leptin (P < 0.01); observed increases in mean and peak leptin were greatest for abdominal fat mass (50% and 56% increase for every extra 100 g, respectively). After weight gain, postprandial leptin concentration increased markedly relative to when cats were lean, and the duration of the increase was longer after a mean weight gain of 37% with the low-carbohydrate, high-protein diet group compared with 17% with the high-carbohydrate, low-protein group (P ≤ 0.01). Adiponectin was lower than fasting at some time points during the postprandial period in both groups (P ≤ 0.05). For both fasting and mean 24-h adiponectin, there was no significant diet effect (P ≥ 0.19) or changes in weight gain relative to when cats were lean (P ≥ 0.29). In conclusion, fat mass, and not diet, has a large effect on postprandial leptin but not adiponectin concentrations in cats.  相似文献   
242.
Adiponectin's beneficial effects are mediated by the AdipoR1 and AdipoR2 receptors (AdipoRs). The pig is a good model to study complex disorders such as obesity. We analyzed the expression of adiponectin, AdipoRs and some key molecules of energy metabolism (AMP-activated protein kinase α [AMPKα], p38 mitogen-activated protein kinase [p38 MAPK], and PPARα) in 2 pig breeds that displayed an opposite genetic behavior for energy metabolism: Casertana (CE), a fat-type animal, and Large White (LW), a lean-type animal. Muscle, liver, visceral and subcutaneous adipose tissues, and brain tissues were examined. The AdipoRs cDNA sequences were identical in the 2 breeds. AdipoRs mRNA expression, measured in all tissues, was significantly lower only in the 2 adipose tissues of CE pigs (P < 0.05). The muscle expression of AdipoRs, AMPKα, p38 MAPK, and PPARα was lower in CE than in LW animals (P < 0.01, P < 0.05, P < 0.01, P < 0.01, respectively). In liver, no molecule differed between breeds. The expression of both AdipoRs in visceral and subcutaneous adipose tissues was lower in CE pigs (P < 0.01). In brain, AdipoR1 and AMPKα expression was lower in CE pigs (P < 0.01), whereas AdipoR2 tended to be lower in CE than LW pigs (P = 0.05). In conclusion, our results suggest that tissue-specific downregulation of Adiponectin, AdipoRs, and of the key molecules of energy metabolism may be associated with the tendency of CE pigs to accumulate fat.  相似文献   
243.
Abstract

This study was conducted to evaluate the effect of fermented fish waste (FW) on the digestion of fiber and the flow of unsaturated fatty acids (UFA) to the duodenum and plasma in cattle. Four Holstein cows were used in a 4×4 Latin square design and cows were provided with one of four treatments consisting 0, 5.5, 11, and 16.5% of FW. The digestion of dry matter decreased as the FW increased; however, the lipid concentration increased linearly (P<0.05) as the FW increased. According to the duodenal composition, the lipid concentration and UFA such as conjugated linoleic acid (CLA), arachidonic acid, and docosahexaenoic acid (DHA) increased linearly (P<0.05) as the amount of FW increased in the diet. Additionally, the concentration of CLA, eicosapentaenoic acid and DHA increased linearly (P<0.05) in the plasma as the FW increased. Thus, these findings indicate that FW can be useful as UFA supplementation of feedstuff.  相似文献   
244.
近红外反射光谱新方法测定乳清蛋白浓缩物品质的研究   总被引:1,自引:0,他引:1  
本文比较了近红外反射光谱(NIRS)和传统的化学方法测定乳清蛋白浓缩物的蛋白质、脂肪、水分的效果。结果发现,用近红外反射光谱法有很好的效果,完全可以代替传统的化学方法,且快速、简便、准确且无药品污染。  相似文献   
245.
抽取消毒纯牛奶、酸奶、橙味酸奶露、桃味优爽和优酸乳的生产样品,从色泽、滋气味和组织状态3个方面对样品进行了感官评定;采用牛奶成分分析仪和阿贝折光仪测定了样品的脂肪、蛋白质、非脂乳固体及可溶性固形物的含量;用碱式滴定法测定了酸度。结果表明,消毒纯牛奶的脂肪和蛋白质含量最高,几种酸牛奶的非脂乳固体含量、酸度相对较高;优酸乳的可溶性固形物含量相对较高;酸奶露和桃味优爽的各理化指标相对较低。  相似文献   
246.
榛子果仁干物质与脂肪增长速率及积累规律的研究   总被引:1,自引:0,他引:1  
魏丽红  翟秋喜 《安徽农业科学》2011,(19):11574-11575
以杂种榛优良品系为试材,采用动态监测的方法,研究果仁发育过程中干物质和脂肪的含量变化及增长速率。结果表明,3种榛子品系果仁干物质及脂肪的累积主要在果仁发育的前期和中期,果仁干物质及脂肪的积累基本是同步进行的。  相似文献   
247.
对江苏沿海地区肉丰养殖业的发展现状进行阐述,从肥羔肉市场、肥羔业发展趋势、现代肥羔生产技术要求等方面对沿海地区肥羔产业发展前景进行论述,表明肥羔生产是江苏沿海地区养羊业转变生产模式、焕发生机的重要途径。  相似文献   
248.
脂肪含量是大豆品质的重要指标之一,运用多种数理统计方法,对黄淮海区试南组5年夏大豆区域试验测定的大豆品种脂肪含量与平行观测的气象资料进行分析。结果表明:影响脂肪含量的综合气候关键期为9月上、中旬(鼓粒中后期),主导气象因子是日照时数,气温日较差对其也有重要影响。  相似文献   
249.

Background

A study was undertaken to examine the effects of poultry fat (PF) compared with those of soybean oil (SBO) on intestinal development, fatty acid transporter protein (FATP) mRNA expression, and fatty acid composition in broiler chickens. A total of 144 day-old male commercial broilers were randomly allocated to 2 treatment groups (6 replicates of 12 chicks for each treatment) and fed isocaloric diets containing 3.0% PF or 2.7% SBO at 0 to 3 wk and 3.8% PF or 3.5% SBO at 4 to 6 wk, respectively.

Results

PF had no influence on intestinal morphology, weight, or DNA, RNA, or protein concentrations at 2, 4, and 6 wk of age. However, compared with SBO, PF significantly decreased FATP mRNA abundance at 4 wk (P = 0.009) and 6 wk of age (P < 0.001); decreased liver fatty acid-binding protein (L-FABP) mRNA abundance at 6 wk of age (P = 0.039); and decreased C18:2 (P = 0.015), C18:3 (P < 0.001), C20:2 (P = 0.018), Σ-polyunsaturated fatty acids (Σ-PUFA) (P = 0.020), and the proportion of PUFA (P < 0.001) in the intestinal mucosa and decreased C18:2 (P = 0.010), C18:3 (P < 0.001), C20:2 (P < 0.001), Σ-PUFA (P = 0.005), and the proportion of PUFA (P < 0.001) in breast muscle at 6 wk of age.

Conclusions

PF decreases FATP and L-FABP mRNA expression and decreased the proportion of PUFA in the intestinal mucosa and breast muscle.  相似文献   
250.
猪脂肪沉积的品系差异及其cAMP的调控作用   总被引:12,自引:3,他引:9  
体重、健康状况相近的8月龄混系和丹系长白肥育猪16头,空腹采血测定cAMP、胰岛素、激素敏感脂酶(HSL)、游离脂肪酸(FFA)和甘油三酯;屠宰后测定胴体指标,并采背部脂肪和肝脏组织,分析了cAMP和腺苷酸环化酶(AC)活性以及脂肪组织中脂肪酸组成.结果表明,与混系相比,丹系瘦肉率、眼肌面积和后腿比分别高9.44%(P<0.01)、9.67%和4.00%,背膘厚、脂肪率和板油比分别低7.97%、18.10%(P<0.05)和14.25%。血浆cAMP、HSL和FFA分别比混系高32.85%(P<0.05)、7.41%和123.41%;甘油三酯和胰岛素则分别低12.23%和18.06%.丹系脂肪组织中总脂,14碳和16碳脂肪酸分别高10.85%、39.66%(P<0.01)和7.31%,而18碳脂肪酸则低4.31%;丹系肝和脂肪组织中cAMP和AC显著高于混系。结果证明,猪脂肪沉积的品系差异与肝、脂肪组织及血中cAMP的水平有关,脂肪沉积的cAMP调控具有明显的品系差异。  相似文献   
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