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941.
The aim of the present study was to investigate the influences of Aspergillus niger fermented rapeseed meal (FRSM) on growth performance and nutrient digestibility of growing pigs. A total of 72 growing pigs (body weight = 40.8 ± 2.1 kg) were used in feeding trials, lasting for up to 42 days, and were randomly allotted to one of three diets, including a corn‐soybean meal control diet as well as two experimental diets containing 10% unfermented rapeseed meal (RSM) or 10% FRSM. The results showed that average daily gain and feed conversion ratio of pigs fed FRSM were superior (P < 0.05) to that of pigs fed unfermented RSM and did not differ from the control. Pigs fed control diet had higher (P < 0.05) total tract apparent digestibility for dry matter, protein, calcium and phosphorus than pigs fed unfermented RSM diet and did not differ from the FRSM diet. Pigs fed FRSM had lower levels (P < 0.05) of serum aspartate transaminase compared to unfermented RSM. In conclusion, solid state fermentation using Aspergillus niger may improve the growth performance and nutrient digestibility of RSM for pigs and FRSM is a promising alternative protein for pig production.  相似文献   
942.
The objective of the present experiment was to determine the effect of different types of N-carbamoylglutamate on growth performance,serum biochemical indexes and fat distribution of Tan sheep. Sixty male Tan lambs with average weight of (20.14±0.31)kg and similar age were randomly assigned three groups with five replications per group and 4 lambs per replication. The lambs in control group were fed basal diet, while lambs in test groups were fed diets containing 0.1% NCG and 0.1% RP-NCG,respectively. The results showed that:① Comparing with control group,the ADG was significantly improved (P<0.05) and F/G was significantly decreased (P<0.05) when 0.1% NCG or 0.1% RP-NCG were supplemented,while there was no significant difference between two experimental groups (P>0.05).② Dietary supplemented with 0.1% NCG or 0.1% RP-NCG significantly decreased the serum urea nitrogen (P<0.05),but there were no significant differences in serum total protein,creatinine content and creatine kinase activity (P>0.05).③ The ration of meat weight to carcass weight of two experimental groups was significantly improved (P<0.05).As 0.1% NCG or 0.1% RP-NCG were supplemented in the diets, the content of subcutaneous fat and GR value were significantly decreased (P<0.05),and the content of intramuscular fat (IMF) was significantly increased (P<0.05).In conclusion,dietary supplemented with 0.1% NCG or 0.1% RP-NCG could improve the growth performance and slaughter performance while there was no significant difference between NCG and RP-NCG.  相似文献   
943.
The objective of the present study was to evaluate the potential effect of dietary calcium butyrate on growth performance, carcass traits and gut health in Japanese quails. In total, 320 one‐day‐old Japanese quails were randomly assigned to 4 equal treatments, with 8 replicates of 10 Japanese quails, for 4 weeks. The Japanese quails in control treatment were fed control diet whereas in the other treatments the Japanese quails were fed diet supplemented with calcium butyrate at 0.3, 0.5 and 0.7 g/kg diet. Data concerning performance measurements were recorded weekly. In addition, eight Japanese quails (one/replicate) from each treatment were selected randomly for serum collection to measure pro‐ and anti‐inflammatory cytokines. Pooled faecal samples from each replicate of each treatment were also collected at three time points (0, 2 and 4 weeks) for count E. coli and C. perfringens. The results showed that after 7 days of the experimental period, Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg showed a greater (p < .05) body weight and a favourable (p < .05) feed conversion ratio than the other treatments. Moreover, serum superoxide dismutase and catalase activities were increased (p < .05) in Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg. Calcium butyrate supplementation at 0.7 g/kg was associated with reduction (p < .05) in TNF‐α, IL‐6 and IL1‐β, while IL‐10 was increased (p < .05). In addition, after 2 weeks of calcium butyrate supplementation, a reduction (p < .05) in E. coli and C. perfringens counts was observed in excreta of Japanese quails fed 0.5 and 0.7 g calcium butyrate/kg diets. It is concluded that calcium butyrate supplementation improves body weight gain, reduces E. coli and C. perfringens counts and has anti‐inflammatory/anti‐oxidant effect in Japanese quails.  相似文献   
944.
为研究日粮中添加藜麦秸秆对奶牛生产性能和血清生化指标的影响,试验根据胎次相同,产犊时间、体重、产奶量相近的原则,选择16头中国荷斯坦奶牛作为试验牛。采用单因子随机试验设计,随机分为4组,每组4头牛,分别饲喂4种不同比例藜麦秸秆的全混合日粮(TMR)。藜麦秸秆的干物质(DM)添加比例分别为0%(Ⅰ组),5%(Ⅱ组),10%(Ⅲ组),15%(Ⅳ组)。预试期10d,正式期60d。结果表明:试验Ⅱ、Ⅲ组的产奶量、4%标准乳产量显著高于试验Ⅰ组(P<0.05),试验Ⅱ、Ⅲ组的产奶量分别比试验Ⅰ组高6.58%和6.87%,试验Ⅱ、Ⅲ组的4%标准乳分别比试验Ⅰ组高5.37%和10.61%;试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组的乳脂率、乳糖率、乳蛋白率和乳总固形物差异均不显著(P>0.05);试验Ⅰ、Ⅱ、Ⅲ组和Ⅳ组的粗蛋白质(CP)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)的表观消化率差异不显著(P>0.05);试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组葡萄糖、甘油三酯、高密度脂蛋白、低密度脂蛋白、尿素氮、总蛋白、白蛋白、球蛋白、谷丙转氨酶、谷草转氨酶和碱性磷酸酶差异均不显著(P>0.05)。综上所述,奶牛日粮中添加藜麦秸秆能提高其产奶量,对血清生化指标无不利影响。  相似文献   
945.
本试验以不同脂肪源配制成等氮等脂的7种饲料,对大菱鲆[(27.31±0.10)g]进行40 d的饲养试验,旨在探讨不同饲料脂肪源对大菱鲆生长、体组成、血清生化指标的影响。7种饲料分别添加6%的鱼油(FO)、大豆油(SO)、菜籽油(RO)、花生油(PO)、猪油(L)、鱼油-豆油(1∶1)(FSO)和鱼油-豆油-猪油(3∶4∶3)的混合油(MIX)。每组饲料设3个重复,每个重复12尾鱼。研究结果表明:(1)鱼油-豆油组特定生长率显著高于其他各组,较鱼油组(基础饲料组)提高了10.42%(P < 0.05),猪油组特定生长率最低,较鱼油组降低了19.79%(P < 0.05)。猪油、混合油、花生油组饲料系数分别较鱼油组提高了36.36%、33.33%、25.25%(P < 0.05),其余各组间无显著差异(P > 0.05);(2)饲料脂肪源对大菱鲆鱼体水分、粗脂肪和粗灰分含量影响不显著(P > 0.05),猪油组粗蛋白质含量显著低于鱼油组、菜籽油组和花生油组,其中较鱼油组降低了4.47%(P < 0.05)。摄食不同脂肪源饲料的大菱鲆空壳、内脏和背肌的脂肪含量差异不显著(P > 0.05),猪油组空壳的水分显著高于菜籽油组和混合油组(P < 0.05);(3)各试验组总胆固醇、甘油三酯、高密度脂蛋白胆固醇和碱性磷酸酶含量无显著差异(P > 0.05)。猪油组和混合油组的谷丙转氨酶含量显著高于其他各组,较鱼油组分别升高了124.89%和119.94%(P < 0.05),混合油组的谷草转氨酶含量显著高于其他各组,较鱼油组提高了352.51%(P < 0.05),表明猪油组和混合油组鱼体肝脏受到一定程度的损伤。综合以上7种饲料脂肪源对鱼体生长性能、体组成及血清生化指标的影响,鱼油-豆油(1∶1)、豆油和菜籽油可作为大菱鲆饲料合适的脂肪源,而猪油、混合油不适宜作为大菱鲆的饲料脂肪源。  相似文献   
946.
东方田鼠具有天然抗日本血吸虫病特征,为了探索东方田鼠抗日本血吸虫机制,本研究分析了东方田鼠和小鼠感染日本血吸虫尾蚴前后血液细胞以及生化指标的动态变化。东方田鼠和BALB/c鼠定量感染日本血吸虫尾蚴,于感染后第0、1、3、5、8、12、16、21、28、35、42 d分别采集抗凝血和血清,进行血常规和血清生化分析。血常规检测结果表明,东方田鼠感染后第3~16 d,WBC数量显著升高(Neu数量显著升高),而小鼠血常规检测结果正常;血清生化结果显示,东方田鼠感染日本血吸虫后ALB、HDL-C显著升高,小鼠各指标变化不明显。本研究结果显示东方田鼠天然免疫细胞Neu和血清ALB可能与其抗日本血吸虫特性相关,对补体杀伤日本血吸虫机制研究具有重要的指导意义。  相似文献   
947.
为了研究蓝耳病不同毒株疫苗在ADE效应下的表现,将疫苗血清复合物(用105.0TCID50的HP-PRRSV田间分离株ZJ-2014,与不同弱毒疫苗CH-1R、R98、TJM-F92的免疫血清在不同的稀释梯度下混合作用24 h,获得血清复合物)接种于PAM细胞,进行蓝耳病病毒增殖试验,检测病毒RNA拷贝数。以兔抗猪FcγRIIb血清进行封闭构建对照组,而后接种PAM细胞。通过比较封闭前后PRRS病毒增殖数量的差异,确定不同疫苗血清兔抗猪FcγRIIb多抗对ADE的阻断作用。试验结果表明:TJM-F92株疫苗的血清抗原复合物对ADE效应的阻断效果最为明显,提示在未来蓝耳病疫苗研制及临床应用中,TJMF92株可以成为优选毒株。  相似文献   
948.
The objective of this study was to evaluate the effects of spray‐dried porcine plasma (SDPP) on performance, measurement of thyroid hormones triiodothyronine (T3) and thyroxine (T4), body temperature and relative organ weights of weaned piglets exposed to a heat stress or a thermoneutral environment. One hundred and forty‐four piglets with initial BW of 5.82 ± 0.33 kg (28 d old) were used. The experimental design was a 4 x 2 factorial arrangement, four plasma levels (0.0, 2.5, 5.0 and 7.5%) and two environments (34º [heat stress (HS)] and 24°C [thermoneutral (TN)]). SDPP was fed from weaning (28 d of age) to the end of the trial (piglets were weighed at the beginning, 7, 21 and 35 days of trial). Rectal, neck, shoulder and leg temperatures were measured every seven days. At 21 days of trial, one piglet per pen was slaughtered to determine the weight of the carcass and organs. Blood samples were collected at 18 and 35 days of trial to determine levels T3 and T4. The rectal, neck, shoulder and leg temperatures were increased (p < 0.05) 0.4, 1.5, 1.0 and 1.3ºC, respectively, and relative weight of the lungs (p < 0.05) and total T3 (p < 0.05) were decreased 0.001 kg/kg and 0.19 ng/dl, respectively, for pigs in the HS environment. The estimated inclusion of 5.1% of SDPP had the greatest (p < 0.05) weight gain during the first week, and throughout the nursery phase, the 5% of inclusion had a tendency of improvement (p = 0.075), regardless of ambient temperature. For the entire period, pigs reared in the HS environment had the greatest (p < 0.05) estimated feed intake by the quadratic regression with the inclusion of 4.3% of SDPP.  相似文献   
949.
950.
Consumption of canned cat food is considered a risk factor for the development of feline hyperthyroidism. Because selenium and water are substantially higher in canned diets compared to dry diets, objectives of this study were to determine whether increased dietary selenium or water alters the function of the hypothalamic–pituitary–thyroid axis and leads to an increase in activity level. Employing a 28‐day latin square design with a 14‐day washout, six lean, neutered male domestic shorthair cats were fed (i) commercially available adult dry feline diet containing 0.8 ppm selenium (control), (ii) control diet with added sodium selenite to achieve a dietary selenium concentration of 1.125 ppm (selenium treatment) and (iii) the control diet with additional water to achieve a moisture content of 75% wt/wt (water treatment). Water consumption was determined using deuterium oxide washout. Actical activity monitors were placed on each cat's collar to allow quantification of the activity of each cat. Circulating serum T3 and T4 was measured on days 0, 14, and 28. On day 28, a thyrotropin‐releasing hormone (TRH) stimulation test was conducted to determine treatment effects on serum concentrations of thyroid hormones. There was a significant increase in daily water consumption with dietary water treatment (192 ml ± 7.85 SEM) compared to the control (120 ml ± 20.4) and selenium (116 ml ± 14.6) treatments. Both water and selenium treatments were associated with greater (p < .05) activity over that of the control treatment by 20.5% and 11% respectively. Serum TT3 AUC concentrations (0–4 hr) of TRH stimulation tests were greater (p < .05) by 16% with water compared to control treatments. The results of this study indicate that dietary water content may alter the function of the thyroid axis and that this effect is associated with an increase in physical activity.  相似文献   
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