不同繁育饲养设施对Beagle犬生产性能的影响

目的探索不同繁育饲养设施对Beagle犬主要生产性能的影响。方法使用两种不同Beagle犬繁育饲养设施（设施Ⅰ、设施Ⅱ）对母犬产仔状况、仔犬初生重、60 d离乳犬只存活率、60 d离乳犬只体重、1～6月龄犬只体重月增长等生产性能进行了比较研究。结果两种设施比较母犬产仔状况,仔犬初生重无差异（P〉0.05）;设施Ⅱ比设施Ⅰ的60 d离乳犬只存活率高18.4%,差异极显著（P〈0.01）,60日龄离乳犬只体重平均多（0.62±0.13）kg,差异极显著（P〈0.01）;1～6月龄犬只体重月增长平均多0.29±0.14 kg,差异近显著（P=0.08〉0.05）。结论设施Ⅱ优于设施Ⅰ。     

Beagle犬免疫血清犬瘟热抗体检测

采用琼脂扩散法测定血清抗体效价,同时采用微量细胞中和实验测定中和效价,检测60份Beagle犬免疫血清犬瘟热(CD)抗体.结果表明25日龄仔犬血清母源抗体维持在较高的水平,以后逐渐下降,至35日龄(首免日)血清母源抗体水平下降1～2个滴度,首免后1个月、3个月、6个月免疫抗体水平逐渐上升.根据抗体水平应选择35日龄首免.本试验为 Beagle犬瘟热病预防选择疫苗和制定合适的免疫程序提供参考,实验设定的两种免疫程序在临床上都可以使用.     

6～8月龄Beagle犬的生理、生化参数检测

目的测定6～8月龄Beagle犬正常生理、生化等数据,为药理、毒理试验提供对照参考.方法血液学、血液生化学、血清激素水平、血压、呼吸、心电图、骨髓象、脏器系数等指标均按现临床检测方法进行.结果 48头6～8月龄Beagle犬(雌雄各半)的正常生理、生化参数,血清激素水平,骨髓象及主要脏器的系数均取得平均值及标准差范围.结论 6～8月龄正常Beaele犬生理、生化等参数的个体差异较小,本研究结果可作为新药Beagle犬长毒试验中各项测试的正常值参考.     

日粮蛋白质水平对断奶仔猪肠道发育的影响

实验研究了饲粮不同粗蛋白水平对断奶仔猪肠黏膜形态和肠道健康状况的影响.实验采用完全随机设计,将72头28日龄断奶的仔猪分为4组,每组3个重复,每个重复6头.4个组分别接受24%、22%、20%、18%蛋白水平的日粮.结果表明,采食粗蛋白水平为24%的日粮使小肠不同肠段绒毛的生长受到了抑制,使隐窝加深、绒毛/隐窝比降低;随着日粮粗蛋白水平的下降,回肠和盲肠消化物pH、氨氮浓度显著降低(P<0.05),盲肠消化物中腐胺浓度显著降低(P<0.01).采食粗蛋白水平为24%的仔猪有轻度腹泻现象.上述结果提示,适当降低断奶仔猪日粮粗蛋白水平并平衡主要必需氨基酸,有利于降低肠道有害菌群的增殖,改善肠道健康状况.     

不同精氨酸添加水平对哺乳仔猪生长性能的影响

为了研究日粮中不同精氨酸(Arg)水平对哺乳仔猪生长性能的影响,试验选用70头7日龄健康哺乳仔猪(长×大),按照所饲日粮精氨酸添加水平的不同(分别为0、0.2%、0.4%、0.6%和0.8%),随机分为5组,每组14头,单栏饲养,试验期为14 天,并分别于7、14和21日龄空腹称重,记录每周采食量;并在采食后1 h颈静脉采血,检测血浆中氨基酸、血浆尿素氮、胰岛素和生长激素浓度.结果表明:7～21日龄段,试验组血浆精氨酸浓度随日粮精氨酸添加水平增大而升高,与对照组相比,0.6%和0.8%精氨酸添加组血浆尿素氮水平分别降低(P<0.05)30%～40%,生长激素和胰岛素的浓度提高(P<0.05)24%～27%,平均日增重分别提高了(P<0.05)42.2%和41.4%;各组采食量在整个试验期内无显著差异.本试验结果表明7～21日龄,仔猪日粮中精氨酸适宜添加水平为0.6%.     

长爪沙鼠生长繁殖性能的研究

目的　动物的生长繁殖性能是其生理学数据的重要组成部分 ,对实验动物的开发和应用具有指导意义。方法　选择离乳的长爪沙鼠 80只 (雌雄各半 ) ,一雌一雄长期同居。结果　每胎产仔 3～ 7只的居多 ,占总胎数的 77% ;平均每胎产仔 (5 .0 2± 2 .1 1 )只 ;每年产仔胎数 5～ 9胎的较多 ,占总胎数的 91 .7% ,平均 (7.4 9± 2 .0 1 )胎 /年 ;最早的初产周龄为 1 3周龄 ,最长的 5 2周龄 ,在 1 3～ 2 0和 2 5～ 2 8周龄的居多 ,占总对数的 80 %。长爪沙鼠的平均出生重为 3.5g ,成年鼠平均体重雌性 5 5 .6g ,雄性 6 7.2g。结论　普通级长爪沙鼠封闭群配种日龄最早在 6 5日龄 ,初产日龄超过 2 0 0日龄的长爪沙鼠应淘汰 ;性别对长爪沙鼠体重无显著影响     

成年Beagle犬生物学指标及心电图检测值统计分析

目的 测定正常Beagle犬生理指标,比较不同性别间各参数的差异,以建立健康成年Beagle犬相关生理学参数的基础正常值.方法 根据国家(成都)中药安全性评价中心制定的标准操作规程(SOP)并参照国内外相关资料,对200只4～8月龄Beagle犬的心电图、血压、呼吸、血液学及血液生化等指标进行检测.结果 200只犬均为窦性心律,雌性犬心率较雄性快(P<0.01);血液学指标中RBC、Hb及HCT值雌性均低于雄性,差异有统计学意义(P<0.01);血生化指标中雌性犬高于雄性的是BUN(P<0.05);雌性犬低于雄性的是TP、ALB、GLU、TC及K+的含量(P<0.05或P<0.01).结论 在本实验室条件下,雌雄Beagle犬之间部分指标有统计学差异,本结果可为Beagle犬的实验提供正常值参考.     

粗纤维对定安鹅MSTN基因表达量及肌纤维发育的影响

为研究日粮粗纤维水平对生长中期定安鹅腿肌MSTN基因表达量及肌纤维发育的影响,选遗传背景相近、体重一致的30日龄定安鹅120只,采用单因子随机试验设计,共分3个处理组,每处理组设4个重复,每重复10只鹅.分别饲喂粗纤维水平为4.29％,5.29％和6.29％的三种日粮.试验期为35 d.结果表明:(1)日粮粗纤维水平为5.29％时,可以提高生长中期定安鹅试验末重和平均日增重,并且与6.29％组比较达到了显著水平(P＜0.05);(2)日粮粗纤维水平可以显著影响生长中期定安鹅腿肌中MSTN的基因表达量(P＜0.05),且腿肌中MSTN的基因表达量与生长中期定安鹅的试验末体重和平均日增重呈负相关关系;(3)日粮粗纤维水平为5.29％时,与6.29％组相比可显著提高生长中期定安鹅血清中IgA和IgG的含量(P＜0.05);(4)日粮粗纤维水平显著影响生长中期定安鹅腿肌纤维数量和腿肌纤维密度的影响(P＜0.05).综上所述,日粮粗纤维水平为5.29％可以显著影响生长中期定安鹅的试验末体重、平均日增重和腿肌中MSTN基因的表达水平,对腿肌纤维的发育也有一定的促进作用.     

复合活菌制剂对断奶仔猪生长性能及血清溶菌酶含量的影响

目的观察复合活菌制剂对断奶仔猪生长性能及血清溶菌酶含量的影响。方法选择长白二元杂交断奶仔猪90头进行实验,断奶日龄为35 d。共分为5个组,每组设3个重复,每个重复随机选取健康仔猪6头。实验组一:饲喂基础日粮+0.1%复合制剂(纳豆杆菌,双歧杆菌,罗伊乳杆菌),实验组二:饲喂基础日粮+0.1%复合制剂(纳豆杆菌,双歧杆菌,干酪乳杆菌),实验组三:饲喂基础日粮+0.1%复合制剂(纳豆杆菌,双歧杆菌,嗜酸乳杆菌),实验组四:饲喂基础日粮+0.1%复合制剂(纳豆杆菌,双歧杆菌,罗伊乳杆菌,干酪乳杆菌,嗜酸乳杆菌),对照组:饲喂基础日粮。其中复合制剂中益生菌活菌数为109CFU/g。饲养30 d后观察复合活菌制剂对断奶仔猪生长性能及血清溶菌酶含量的影响。结果在日增重、饲料效率及血清溶菌酶方面,实验组一和二显著高于对照组(P0.05);在腹泻率方面,实验组均显著低于对照组(P0.05)。结论在仔猪日粮中添加复合活菌制剂可提高每头断奶仔猪平均日增重及饲料效率,降低腹泻的发病率,且增高仔猪血清溶菌酶含量,提高仔猪的免疫机能,从而提高经济效益。     

日本大耳白黑眼兔在不同生长阶段蛋白质营养与肝脏相关基因表达的关系

目的研究日粮粗蛋白水平和生长阶段对日本大耳白黑眼兔（WHBE兔）肝脏相关基因表达的影响。方法采用两因素实验设计,分别选取断奶和2月龄WHBE兔各20只进行为期1个月的幼兔期和育成兔期饲养实验,每个阶段实验均将兔随机分为5组,各组日粮粗蛋白水平分别为12%、14%、16%、18%和20%,实验结束,用实时荧光定量PCR技术测定肝脏胰岛素样生长因子-1（IGF-1）和磷酸烯醇式丙酮酸羧激酶-C（PEPCK-C）的mRNA的表达丰度。结果生长阶段和粗蛋白水平均对WHBE兔肝脏IGF-1mRNA的表达丰度有显著影响,育成兔期IGF-1 mRNA的表达丰度明显高于幼兔期;日粮粗蛋白水平为16%和18%时IGF-1mRNA表达丰度较高,显著高于其他3组。PEPCK-C mRNA的表达也以16%粗蛋白组最高,幼兔期和育成兔期之间差异无显著性。结论日粮粗蛋白水平对IGF-1和PEPCK-C基因表达有显著影响,生长阶段与IGF-1mRNA表达密切相关。     

饲料中添加胆汁酸对牛蛙生长性能、体组成和营养物质表观消化率的影响

试验研究了饲料中添加胆汁酸对牛蛙Rana (Lithobates) catesbeiana生长性能、体成分和营养物质表观消化率的影响。基础饲料以鱼粉、豆粕为主要蛋白源, 棕榈油为主要脂肪源, 在基础饲料中分别添加0、100、200和300 mg/kg的胆汁酸(含量99.1%)制作4种等氮等能的试验饲料。试验将144只牛蛙初始体重(75.014.23) g随机分为4组, 每组3个重复, 每个重复12只牛蛙, 进行为期8周的生长试验。结果显示: 各试验组牛蛙成活率和摄食率差异不显著(P0.05)。200 mg/kg胆汁酸添加组牛蛙的增重率、特定生长率、饲料效率、蛋白质效率和氮保留率显著高于对照组(P0.05)。在饲料中添加胆汁酸显著降低了牛蛙脏体指数和全体的脂肪含量(P0.05), 但不影响肌肉粗脂肪以及全体和肌肉水分、粗蛋白、粗灰分含量(P0.05)。各处理组间血清总胆固醇、甘油三酯、高密度脂蛋白胆固醇和低密度脂蛋白胆固醇浓度均无显著变化(P0.05), 血清尿素氮含量随着饲料中胆汁酸添加量的增加而降低, 添加300 mg/kg胆汁酸组牛蛙血清尿素氮含量显著低于对照组(P0.05)。血糖水平则随着胆汁酸添加量的增加而先降低后升高, 其中100 mg/kg胆汁酸添加组牛蛙血糖水平最低(P0.05)。100 mg/kg胆汁酸添加组牛蛙肠道脂肪酶活力显著高于对照组和300 mg/kg胆汁酸添加组(P0.05), 与200 mg/kg胆汁酸添加组之间差异不显著(P0.05), 蛋白酶活力与脂肪酶活力有相似的变化趋势, 而淀粉酶活力未受胆汁酸添加水平影响。各处理组饲料营养物质的表观消化率随饲料中胆汁酸添加量的增加而先升高后降低, 其中饲料添加200 mg/kg胆汁酸显著增加了牛蛙对饲料营养物质的表观消化率(P0.05)。结果表明: 在饲料中添加适量的胆汁酸能提高牛蛙对饲料的消化率, 提高饲料效率, 从而促进牛蛙的生长, 同时可促进蛙体脂肪代谢, 降低机体脂肪沉积, 提高牛蛙可食部分比例。根据本试验结果, 建议牛蛙饲料中胆汁酸添加水平为200 mg/kg。       

饲料蛋氨酸水平对异育银鲫幼鱼生长性能影响的研究

研究通过8周的生长实验, 研究饲料中不同蛋氨酸水平对异育银鲫(Carassius auratus gibelio)幼鱼生长性能、体成分、氨基酸沉积率的影响。实验以鱼粉、豌豆浓缩蛋白、喷雾干燥血球粉为蛋白源, 设计低蛋氨酸(0.57%)实用基础饲料, 并在此基础上分别添加0、0.08%、0.16%、0.24%、0.32%、0.40%的DL-蛋氨酸配成蛋氨酸含量分别为0.57%、0.64%、0.74%、0.81%、0.88%、0.95%(干物质基础, 实测值)的6种等氮等能(粗蛋白质: 37.22%, 总能: 17.61 MJ/kg)的配合饲料。选取初始体重为2.60 g的异育银鲫幼鱼为实验对象, 每个处理3个重复, 每个重复50尾鱼, 养殖系统为室内循环水养殖系统, 每天表观饱食投喂4次。结果显示在饲料中补充DL-蛋氨酸会显著提高异育银鲫幼鱼的特定生长率和蛋白质沉积率(P0.05), 表明异育银鲫可有效利用外源DL-蛋氨酸。各处理组实验鱼肥满度、肝体比、脏体比差异不显著(P0.05), 不同蛋氨酸水平对全鱼水分、粗脂肪、能量没有产生显著影响(P0.05), 补充DL-蛋氨酸显著提高鱼体的粗蛋白质含量, 灰分含量显著降低(P0.05)。随着饲料中蛋氨酸水平的提高, 全鱼蛋氨酸沉积率显著降低, 之后再升高(P 0.05)。补充DL-蛋氨酸可以有效促进其他必需氨基酸在鱼体内的沉积。在饲料中胱氨酸水平为0.42%时, 通过折线模型回归分析, 以蛋氨酸沉积率得到的异育银鲫幼鱼蛋氨酸需求量为占饲料干物质的0.89%, 即占饲料蛋白的2.17%。       

Supplementation with branched-chain amino acids to a low-protein diet regulates intestinal expression of amino acid and peptide transporters in weanling pigs

This study determined the effects of dietary branched-chain amino acids (AA) (BCAA) on growth performance, expression of jejunal AA and peptide transporters, and the colonic microflora of weanling piglets fed a low-protein (LP) diet. One hundred and eight Large White × Landrace × Duroc piglets (weaned at 28 days of age) were fed a normal protein diet (NP, 20.9 % crude protein), an LP diet (LP, 17.1 % crude protein), or an LP diet supplemented with BCAA (LP + BCAA, 17.9 % crude protein) for 14 days. Dietary protein restriction reduced piglet growth performance and small-intestinal villous height, which were restored by BCAA supplementation to the LP diet to values for the NP diet. Serum concentrations of BCAA were reduced in piglets fed the LP diet while those in piglets fed the LP + BCAA diet were similar to values for the NP group. mRNA levels for Na⁺-neutral AA exchanger-2, cationic AA transporter-1, b^0,+ AA transporter, and 4F2 heavy chain were more abundant in piglets fed the LP + BCAA diet than the LP diet. However, mRNA and protein levels for peptide transporter-1 were lower in piglets fed the LP + BCAA diet as compared to the LP diet. The colonic microflora did not differ among the three groups of pigs. In conclusion, growth performance, intestinal development, and intestinal expression of AA transporters in weanling piglets are enhanced by BCAA supplementation to LP diets. Our findings provide a new molecular basis for further understanding of BCAA as functional AA in animal nutrition.     

Effect of feeding different protein to energy (P/E) ratios on the growth performance and body composition of Oreochromis niloticus fingerlings

This study evaluated the growth performance and body composition of Oreochromis niloticus fingerlings (average initial weight 16.53 ± 0.44 g) fed 9 experimental diets (A, B, C, D, E, F, G, H and I) containing three different levels of protein (26, 31 and 36 g 100 g^?1) at three different gross energy (GE) levels (16, 19 and 22 MJ kg^?1) for a period of 64 days. Significant differences were observed in the feed consumption, body weight gain, specific growth rate (SGR), condition factor (k), feed conversion ratio (FCR), protein efficiency ratio (PER), net protein retention (NPR) and apparent net energy retention (ANER) values of fish when the energy level of diet was increased at different protein levels. The maximum weight gain, SGR and k were observed on diet F containing 36% protein and an energy level of 19 MJ kg^?1 of dry feed with a protein to energy (P/E) ratio of 18.96 (g protein MJ^?1 GE). A further increase in the energy content of the diet (22 MJ kg^?1) at the same protein level (Diet I) did not produce any improvement in the growth performance. Lowering the energy level at the same protein level significantly affected the growth performance. Fish fed diet B containing 31% protein and a lower energy level of 16 MJ kg^?1 with the same P/E ratio of 18.61 as diet F showed significantly lower weight gain and growth performance than diet F. Diets E and H containing 31% crude protein at all three energy levels produced similar results as diet B. The poorest FCR was observed when the diet contained both lower levels of protein and energy. Fish fed diet G, containing 26% protein at high energy level (22 MJ kg^?1), showed the best PER and NPR values. The PER and NPR were the poorest on diet C containing 36% protein at low energy level (16 MJ kg^?1). The body moisture content at all protein levels decreased (P < 0.05) with the increasing level of dietary energy whereas the body fat content increased (P < 0.05). Similar trends were observed in the body ash and energy content. Increasing the dietary energy content at lower protein levels did not show any difference (P > 0.05) in body protein content. Our results indicated the optimum P/E ratio for O. niloticus as 18.96 g protein per mega joule of gross energy at 36% dietary protein level and a dietary gross energy value of 19 MJ kg^?1.     

Effect of water temperature,feeding frequency,and protein percent in the diet on water quality,growth and behavior of Nile tilapia Oreochromis niloticus (Linnaeus, 1758)

This study evaluated how water temperature (26, 28, and 30°C), number of meals per day (one or two meals), and protein percent in diet (20, 25 and 30%) impact growth performance, biometric indices, and feeding behavior of Nile tilapia, Oreochromis niloticus. Fish were randomly allocated into 18 equal replicate groups. Higher final body weight was observed in fish reared at 30°C and fed one meal per day containing 30% crude protein. Better weight gain, weight gain %, feed conversion ratio, specific growth rate, and condition factor were recorded in fish reared at 26°C and fed one meal per day containing 30% protein. The best length weight relationship was obtained in fish reared at 26°C and fed one meal per day containing 30% crude protein. Shorter feeding duration and duration of appetite inhibition latency were recorded in fish reared at 30°C, fed one meal per day, and given a diet containing 30% protein. The highest proactivity was recorded in fish reared at 30°C, received one meal per day, and with 25% crude protein in their diet. Conclusively, rearing Nile tilapia at 26–30°C with a lower feeding frequency (one meal/day) and a 30% crude protein diet achieved better performance and feeding behavior.     

The apparent reversal of a wasting syndrome by nutritional intervention in Saguinus mystax

One hundred eighty sexually mature Saguinus mystax were imported from Peru in six lots over a period of 1 year. Within 1 year after arrival, the mortality was 60% and the majority of the tamarins showed signs similar to "wasting marmoset syndrome" (WMS). In an effort to improve the survival rate, an open formula diet replaced the commercial closed formula diet that had been fed since arrival of the tamarins. The open formula diet contained 26.2% crude protein, 12.3% ether extract, 43.3% nitrogen free extract and 5.9% crude fiber on a dry matter basis. The diet was evaluated on the basis of palatability, weight gain, mortality, digestibility, nitrogen balance, serum biochemical parameters and blood counts. The mean daily consumption on an as-is basis was 44.8g or 335 Kcal gross energy/Kg of body wt./day. During the 3 month open formula diet evaluation period average weight increased by 56g (p less than .05), mortality decreased demonstratively, and alopecia and chronic diarrhea were nearly eliminated. Mean daily gross energy intake for S. mystax (335 Kcal/Kg of body wt/day) was substantially greater than previously reported values for callitrichids. WMS signs observed in the S. mystax colony were controlled by providing what appears to be an adequate diet.     

高比例棉粕饲料中补充蛋氨酸对中华绒螯蟹幼蟹摄食、生长及抗氧化酶活性的影响

以40%棉粕为主的混合蛋白源制成基础饲料, 分别在其中添加0.00%、0.14%、0.28%、0.42%、0.56%蛋氨酸(分别记为0.00%Met、0.14%Met、0.28%Met、0.42%Met和0.56%Met), 配制了5种等氮等能的试验饲料, 以全鱼粉组(64.4%鱼粉)作为对照, 探讨了在高比例棉粕饲料中补充蛋氨酸对中华绒螯蟹幼蟹(0.390.02) g的摄食率、生长率和机体抗氧化酶活性的影响。结果表明: 与全鱼粉对照组相比, 0.42%Met组的增重率、特定生长率和饲料系数均无显著差异(P0.05), 但其显著高于0.00%Met、0.14%Met和0.28%Met组(P0.05); 增重率和特定生长率则显著高于0.56%Met组(P0.05); 从幼蟹的摄食量和蛋白质沉积率来看, 0.42%Met和0.28%Met组的摄食量与对照组相似, 当蛋氨酸的补充量低于0.28%或高于0.42%时, 幼蟹的摄食量均有所下降; 统计表明, 对照组的蛋白质沉积率最高(23.20%), 在各试验组中, 0.28%Met和0.42%Met组之间的蛋白质沉积率无显著差异(P0.05), 但显著高于0.00%Met、0.14%Met和0.56%Met组(P0.05); 分析幼蟹的肠道胰蛋白酶活性, 发现0.42%Met组与对照组之间无显著性差异(P0.05), 但均显著高于其他各试验组(P0.05); 0.28%Met、0.42%Met和0.56%Met处理组的血清丙二醛含量、超氧化物歧化酶活性和谷胱甘肽过氧化物酶活性与对照组无显著差异(P0.05)。结果提示, 在高比例植物蛋白(40%棉粕)的基础饲料中, 补充0.42%Met能够显著提高中华绒螯蟹幼蟹的生长率、消化率和抗氧化酶的活性。       

Effect of normal and waxy maize starch on growth, food utilization and hepatic glucose metabolism in European sea bass (Dicentrarchus labrax) juveniles

We determined the effect of dietary starch on growth performance and feed utilization in European sea bass juveniles. Data on the dietary regulation of key hepatic enzymes of the glycolytic, gluconeogenic, lipogenic and amino acid metabolic pathways (hexokinase, HK; glucokinase, GK; pyruvate kinase, PK; fructose-1,6-bisphosphatase, FBPase; glucose-6-phosphatase, G6Pase; glucose-6-phosphate dehydrogenase, G6PD; alanine aminotransferase, ALAT; aspartate aminotransferase, ASAT and glutamate dehydrogenase, GDH) were also measured. Five isonitrogenous (48% crude protein) and isolipidic (14% crude lipids) diets were formulated to contain 10% normal starch (diet NS10), 10% waxy starch (diet WS10), 20% normal starch (diet NS20), 20% waxy starch (diet WS20) or no starch (control diet). Another diet was formulated with no carbohydrate, and contained 68% crude protein and 14% crude lipids (diet HP). Each experimental diet was fed to triplicate groups of 30 fish (initial weight: 23.3 g) on an equivalent feeding scheme for 12 weeks. The best growth performance and feed efficiency were achieved with fish fed the HP diet. Neither the level nor the nature of starch had measurable effects on growth performance of sea bass juveniles. Digestibility of starch was higher with waxy starch and decreased with increasing levels of starch in the diet. Whole-body composition and plasma metabolites, mainly glycemia, were not affected by the level and nature of the dietary starch. Data on enzyme activities suggest that dietary carbohydrates significantly improve protein utilization associated with increased glycolytic enzyme activities (GK and PK), as well as decreased gluconeogenic (FBPase) and amino acid catabolic (GDH) enzyme activities. The nature of dietary carbohydrates tested had little influence on performance criteria.     

Growth rate of tank-reared Mediterranean amberjack, Seriola dumerili (Risso 1810) fed on three different diets

Mediterranean amberjack Seriola dumerili (Risso 1810) has aquaculture potential. The growth rate and food conversion ratio of S. dumerili on three different types of food (A: 100% frozen sardines; B: 50% frozen sardines and 50% pellet; C: 100% pellet) were measured, and analysed with respect to temperature, condition index and chemical composition of the fish fillet. Wild S. dumerili, average body weight 248 g and average total length 26.9 cm were caught in August and September 1994 in the South Adriatic Sea near Dubrovnik, Croatia and kept in three tanks (n=15 in each tank; duration of experiment, 226 days). The fish that were fed on diet A [initial weight, 252 ± 71 g; total length (TL), 24.3 ± 2.6 cm] started feeding immediately; however, fish assigned to diet C began to feed entirely on the pelleted diet 1 month after the start of the experiment. The mortality of fish fed on diet A was negligible, the registered growth rate was 313 ± 74 g (124.2%), specific growth rate was 0.32% day^?1 and the food conversion rate was 6.7. The fish fed on diet B (initial weight, 246 ± 74 g; TL, 28.2 ± 2.5 cm) started to feed on day 3 and achieved a total growth rate of about 98% (final weight gain, 241 ± 69 g) and specific growth rate of 0.24% day^?1 (feed conversion rate of 9.00 and mortality 13%). The fish fed on diet C (initial weight, 246 ± 74 g; TL, 28.2 ± 2.5 cm) started to feed on the pellets after 1 month and had a growth rate of 87% (weight gain 214 ± 85 g), a specific growth rate of 0.24% day^?1 and a food conversion rate of 10.6 with considerable mortality (27%). In all three diet groups the fish grew with considerable variation in food consumption and growth rate, depending on seasonal temperature variations of the ambient sea water supplied to the rearing tanks. Chemical analysis showed that the protein level (amount) in the fish meat exceeded 20% in all three fish fillet samples.     

异育银鲫幼鱼对饲料中缬氨酸需求量的研究

通过65d的生长实验, 探讨饲料中不同缬氨酸水平对异育银鲫(Carassius auratus gibelio)幼鱼平均体重(3.17±0.01)g/尾生长性能、饲料利用和蛋白利用的影响, 确定异育银鲫对饲料中缬氨酸的需要量。实验设计由酪蛋白、明胶和晶体氨基酸为蛋白源的8种等氮(蛋白含量:38%)等能(总能:17.0 kJ/g)的半精制饲料, 其缬氨酸水平等梯度逐步升高(0.54、0.79、1.04、1.29、1.54、1.79、2.04、2.29%饲料干物质)。各实验饲料中缬氨酸的实测值分别为:0.66、0.85、1.07、1.22、1.46、1.70、1.86和2.12%饲料干物质。饲料中其他必需氨基酸含量参照异育银鲫肌肉氨基酸模式。每种饲料饲喂3个重复,每个重复30尾鱼,养殖于塑料方箱中(70 cm×55 cm×50 cm;水体容积:150 L), 养殖系统为室内流水系统(500 mL/min流速), 每天两次饱食连续投喂(9:00和16:00)。实验结果表明,饲料中适量的缬氨酸显著提高了异育银鲫的特定生长率、饲料转化效率和蛋白沉积率(P0.05), 但显著影响了血清谷氨酰胺的浓度(P0.05), 但不同的缬氨酸水平显著影响了鱼体灰分含量(P<0.05)。对各处理组异育银鲫特定生长率的结果进行二次回归分析, 结果表明满足异育银鲫最大生长的缬氨酸需求量为饲料干物质的1.72%, 即占饲料蛋白的4.53%。