天农肥育牛用添加剂饲喂肉牛试验

选择年龄２～３岁，体重３００～４００千克的夏洛来杂公牛，西门塔尔杂交牛及黑白花公牛等品种牛共２０头，用天津农学院研制的“天农肥育牛用添加剂”进行了肥育试验，结果表明：试验组牛平均日增重１．２８２千克，对照组牛为１．０１２千克，试验组比对照组牛平均头日增重多０．２７千克，经ｔ经验两组牛日增重差异显著（Ｐ〈０．０５），经济收益比对照组头日净协１．９３元。     

Influence of several non‐nutrient additives on nonspecific immunity and growth of juvenile turbot,Scophthalmus maximus L.

The effects of three non‐nutrient additives on nonspecific immunity and growth of juvenile turbot (Scophthalmus maximus L.) were studied in this feeding experiment. The five treatments are basal diet alone, basal diets containing three different additives [0.4 g kg^?1 of xylo‐oligosaccharides (XOS), 1.3 g kg ^?1 of yeast cell wall and 0.8 g kg ^?1 of bile acids] individually or in combination. Two hundred and twenty‐five turbots (average initial weight 151.3 ± 11.3 g) were randomly allotted in five treatments with three replicates within each treatment in a 72‐day period. Comparing with basal diet group, activities of C3, C4, phagocyte, lysozyme, specific growth rate and feed conversion rate in yeast cell wall, XOS and the combined groups was enhanced significantly (P < 0.05); however, these parameters in bile acid groups were increased slightly (P > 0.05) except for phagocyte (P < 0.05); superoxide dismutase activity in additive groups was not significantly increased (P > 0.05) except for the combined group (P < 0.05). In conclusion, supplementation of yeast cell wall and XOS enhanced the nonspecific immunity of juvenile turbot. Synergistic or additive effect of the three additives was not observed.     

规则约束下水禽养殖户饲料添加剂使用意愿与行为研究——基于TPB-NAM整合模型

饲料添加剂具有提高动物免疫功能、促进动物健康生长等诸多优势。然而,滥用饲料添加剂已经对动物、人类健康和环境构成了严重的威胁,规范使用饲料添加剂是养殖户亲环境生产行为的重要表现。基于计划行为理论(TPB)和规范激活理论(NAM)的整合框架,利用江西省、湖北省和云南省水禽养殖户微观调查数据,采用结构方程模型,从个体理性和社会理性两个维度,分析在规则约束下水禽养殖户饲料添加剂的使用意愿与行为。结果表明,受访者表现出较高的规范使用饲料添加剂意愿,均值为3.764,但实际行为偏低,均值为3.216。态度、主观规范和感知行为控制均对水禽养殖户规范使用饲料添加剂意愿产生显著正向影响,但影响效应依次减弱;结果意识正向影响责任归属,而责任归属和感知收益共同激活个人规范。意愿与个人规范对水禽养殖户规范使用饲料添加剂行为均具有显著正向影响,且意愿的影响更大,但意愿与行为之间存在悖离现象。据此,提出应采取措施提升水禽养殖户规范使用饲料添加剂的积极态度,强化水禽养殖户在生产过程中所承担的环境责任,营造规范使用饲料添加剂氛围,加大政策支持和补贴力度,加强监管与督察力度等政策建议。     

鲤鱼饲料添加剂的研究

根据鲤鱼的基本营养需求，确定基础饲料（蛋白质，脂肪，碳水化合物）配方后，对１２种无机盐和１２种维生素用数理统计正交试验，设计三个水平Ｌ２７（３＾１３），求出它们的电佳添加量，从而得出符合鲤鱼生理需求的无机盐，维生素综合配方－ＧＳ８９１添加剂。该添加剂经生产规模试验（池塘养鲤，水库网箱养鲤）证实，具有明显的促生长和节约饲料的功效。同期对比，增重率提高３０％以上，饲料系数降低７．９％以上。     

Evaluation of β-(1 → 3, 1 → 6)-glucans and High-M alginate used as immunostimulatory dietary supplement during first feeding and weaning of Atlantic cod (Gadus morhua L.)

Stimulation of the non-specific defence enhances the disease resistance and growth, and has good potentials as a measure for increased microbial control in juvenile production of marine fish and shellfish. So far, the most commonly used immunostimulants are β-(1 → 3, 1 → 6)-glucans, and in this study the stimulatory potential of a β-(1 → 3, 1 → 6)-glucan of marine origin, the storage polysaccharide from the marine diatom Chaetoceros mülleri, was examined. The glucan (chrysolaminaran) was extracted from cultures of C. mülleri, and used as a dietary supplement in two first feeding experiments with larvae of Atlantic cod Gadus morhua L. In one experiment the microalgal glucan was compared to the commercial yeast-glucan product MacroGard®, and in the other to an alginate with a high content of mannuronic acid (High-M alginate) isolated from Durvillaea antarctica. The stimulants were given via rotifers, and weaning to formulated feed was initiated at day 17 or 18 after hatching. The survival ± SEM at day 27 after hatching was 24.5 ± 2.0%, 14.8 ± 4.5% and 13.1 ± 1.4% for the groups fed C. mülleri-glucan, yeast glucan and for the control, respectively, in the first experiment. The group fed C. mülleri-glucan group had higher survival compared to the control (P < 0.05) group, whereas the yeast glucan had no positive effect on the survival (p > 0.05). The dry weights of the groups at day 27 were low, with 203.2 ± 52.2, 165.2 ± 43.4 and 198.5 ± 58.1 μg per larva for the C. mülleri-glucan, yeast glucan and control groups, respectively. In the second experiment the survival in the period of feeding formulated feed (days 18-30) were 44.6 ± 4.3%, 44.7 ± 1.3%, and 33.8 ± 4.1% survival for the C. mülleri-glucan, High-M alginate and control group, respectively. The cod larvae fed C. mülleri-glucan reached an average weight of 531.6 ± 17.2 μg at day 30, which was significantly higher (p < 0.05) than the control group that had an average of 473.6 ± 3.5 μg. The larvae fed High-M alginate had an average weight of 470.3 ± 31.6 μg per larva at day 30, and not significantly different from the control (p > 0.05). The early weaning to formulated diet had detrimental effect on the growth of the larvae. In both experiments the C. mülleri-glucan group was the only group showing a positive growth rate in the period of weaning to dry feed. The microbial conditions in larval gut and water were monitored with respect to total colony forming units on Marine agar, and Vibrio- and Pseudomonas-like species on selective agars (TCBS and marine Pseudomonas Agar with CFC-supplement). The larvae were rapidly colonised after hatching, but no or weak effects of the stimulants were observed on the colonisation rates or the composition. The total CFU varied from 10¹ to 10² CFU per μg larva after initiation of the first feeding. The percentages of Pseudomonas-like bacteria increased throughout the period, whereas the levels of Vibrio-like bacteria were low and stable. The chrysolaminaran from the diatom C. mülleri was shown to be a promising candidate for use as an immunostimulatory feed additive, and which should be further explored.     

Behavioral response to selected feed attractants and stimulants in Pacific white shrimp, Litopenaeus vannamei

Nine commercial feeding attractants and stimulants for Litopenaeus vannamei were evaluated by observation of behavioral responses in animals allotted in one Y-maze aquarium apparatus. In the validation phase, fishmeal–Brazilian origin (FMBO); fishmeal–Peruvian origin (FMPO); blood meal (BM), meat and bone meal (MBM), squid meal (SM), fish oil (FO) and fish solubles (FS) were evaluated. There was also a control without stimulatory raw material. The tested materials were included at 3% in neutral gelatin pellets (wet basis). In each behavioral observation, two different ingredients were offered at the same time in equal quantities, being allotted in the end of each chamber's arm. In Phase II after system validation, the following commercial attractants were tested: 80% crude protein (CP) vegetable dried biomass (VDB₈₀), 68% CP vegetable dried biomass + glutamate + betaine (VDB₆₈), complex of amino acids (alanine, valine, glycine, proline, serine, histidine, glutamic acid, tyrosine and betaine) with enzymatically digested bivalve mollusk (CAA), condensed fish soluble protein (CFSP), squid liver meal (SLM), betaine (Bet), dried fish solubles–low biogenic amines (DFS_LB), dried fish solubles–high biogenic amines (DFS_HB) and whole squid protein hydrolysate (WSPH). Attractants were used at a 3% level wet basis with neutral gelatin, without any additional ingredient source available. The best four commercial attractants from this phase (CAA, CFSP, SLM and WSPH) were compared under 0.5% and 1.0% levels. In Phase I of the study, a higher percentage of choices were observed for FMPO and FMBO. BM and FO were the least chosen ingredients. In Phase II, the worst results were observed for Bet, DFS_HB and, mainly, for VDB₈₀ and VDB₆₈. When two-by-two comparisons were performed, results suggested that CFSP and CAA were the best commercial attractants tested. In the last phase, both CFSP and CAA at 1.0% level were significantly more chosen by shrimp than CFSP (0.5%), SLM (0.5 or 1.0%) or WSPH (0.5 or 1.0%). At both 0.5% and 1.0% levels, shrimp spent a similar amount of time feeding on CFSP and CAA. However, only CAA was statistically better than SLM and WSPH together. Further work is required to better elucidate the chemical drivers of chemostimulation for L. vannamei for each one of the attractants tested.     

微生态制剂在动物园野生动物饲养中的应用

微生态制剂作为一种新型的绿色环保型饲料添加剂,具有调节动物肠道微生态平衡、促进动物生长、提高饲料转化率、提高动物免疫能力等多方面的作用,其应用前景广阔。综述了微生态制剂的类型及作用机理,对其在动物园中增强动物免疫力、提高饲料转化率、减少应激、净化兽舍空气、改善水域水质等方面的应用进行了探讨,同时指出了其在动物园野生动物饲养应用中存在的问题和解决途径。     

观察饲料添加剂二次蓄积对幼犬性激素水平的影响

本试验旨在研究分析市场上正在广泛使用的饲料添加剂,探讨二次饲喂雄性幼犬后饲料添加剂蓄积对其生长、生殖发育的影响研究。选用12只1月龄犬,随机分为试验组和对照组,对照组犬饲喂正常日粮和大鼠鼠肉,试验组犬饲喂正常日粮和高剂量组大鼠鼠肉,喂养幼犬直至成熟,检测食用饲料添加剂高剂量组大鼠鼠肉是否对雄性犬的生长、生殖发育产生影响。采用酶联免疫试剂盒的方法来检测犬血清激素指标水平。结果显示：试验组雌二醇、促卵泡激素含量明显升高（P＜0.01）,而睾酮含量明显降低,有显著性差异（P＜0.01）,饲料添加剂高剂量组对犬血清中的促黄体生成未见显著变化。雄性幼犬食用试验大鼠后可导致雄性幼犬青春期体内内分泌激素含量异常,即青春期11月龄测定的雌二醇以及促卵泡激素水平增高,睾酮的水平降低。提示试验组雄性幼犬食用大鼠鼠肉后,可能通过干扰了睾丸轴的功能,对雄性幼犬的生殖发育能力产生影响。     

中华乌塘鳢人工诱食剂筛选试验

对人工繁育的75日龄中华乌塘鳢（长约4cm，重约0.986g/i）进行一个月饲养试验，从虾粉、海带粉、谷氨酸，甜菜碱，大蒜素等组合成的8种诱食剂中筛选诱食效果最佳者，试验结果表明，在以白鱼粉为主的基础日糖中加入不同配方的诱食剂,对试验鱼的诱食效果不同，其中以2号诱食剂（第三组）的诱食效果最好，增重和成活率拉近鲜虾对照组（第一组）的水平。