Feeding strategy with alternate fasting and refeeding: effects on farmed pacu production

A 36-day trial was conducted to determine the effects of repetitive periods of food restriction and refeeding on growth and energy metabolism in pacu (Piaractus mesopotamicus). A total 264 juvenile fish (36.9±2.8 g) were fed with the experimental diet for 36 days using three regimes: (i) feeding daily to satiation (FD); (ii) no feed for 3 days, then feeding the same amount offered to the control groups for the next 3 days (NF/R controlled); and (iii) no feed for 3 days, then feeding to apparent satiation for the next 3 days (NF/R at satiation). The treatments were distributed into four tanks each. WG and SGR were higher in FD group. Fish refed showed hyperphagia just up to the second day of refeeding. The worst feed conversion rate and the lowest protein efficiency ratio were found in fish NF/R controlled. The lowest values of visceral fat somatic index were found in both fasted fish groups, particularly in NF/R at satiation. The LL and glycogen concentrations, and the hepatosomatic index were all elevated in both feed restricted fish. Muscle lipid showed a tendency to decrease after the cycle of fasting and refeeding. Plasma free fatty acids and glucose levels were elevated in fish subjected to feeding restrictions while serum triglycerides levels were reduced. Triiodothyronine levels were significantly depressed in fish from the NF/R-controlled group and remained at the same levels as the control fish in fish NF/R at satiation. Results indicated that fish subjected to cyclic periods of 3-day satiation or controlled feeding after 3-days of fasting were unable to achieve the final body weight of fish fed to satiation after 36 days.     

有机肥施用量对饲用高梁青贮品质的影响

摘要：采用田间试验研究有机肥（基肥）施用量对饲用高粱（Sorghum bicolor）青贮饲料品质的影响。结果表明,在施氮量相等的条件下,随着有机肥施用量的增加,青贮饲料的发酵品质先增高后下降,施用量以75和150 t/hm2为最好;同时,青贮饲料的酸性洗涤纤维和中性洗涤纤维含量不断增加,粗蛋白含量和干物质体外消化率不断下降。综合青贮饲料的发酵品质和饲用品质,饲用高粱青贮利用栽培时,施用有机肥基肥75～150 t/hm2较适宜。     

关于和顺县种草养牛战略的思考与建议

作者提出了和顺县种草养牛的关键战略措施——种植青贮玉米,阐述了和顺县种植青贮玉米的现状,分析指出存在的问题,提出了实施种植青贮玉米的建议。     

断奶仔猪饲喂流食与颗粒料对比研究

研究流食与颗粒料不同方式对断奶仔猪增重和采食量,选择杜长大三元杂种28日龄仔猪,随机区组设计,共六个区组,每窝一个区组,每个区组四头猪,分为处理组2头和对照组2头。28日龄体重:试验组7.19±0.027 Kg,对照组7.19±0.031 Kg。处理组和对照组均自由采食,自由饮水,35日龄晨称个体重,结果给予流食比使用颗粒料提高仔猪采食量33g/d(P<0.05)和日增重17.6g/d(P<0.05)。仔猪早期断乳是提高母猪生产力和规模化养猪业中的关键技术之一,现代规模养猪业已把乳猪断奶日龄提至21~28 d。     

荣昌乳仔猪小肠黏膜二糖酶活性发育规律及影响因素的研究

为了系统研究荣昌乳仔猪二糖酶的发育规律,为荣昌乳仔猪饲养工艺研究及产业化示范优化补料技术提供理论依据,试验选择30窝胎次、产仔数一致的荣昌乳仔猪随机分为补饲(A)组和非补饲(B)组,A组从6日龄开始补饲,B组不补饲,分别在第0,2,5,8,11,15,19,23,28,30,35天取仔猪十二指肠、空肠(前、中、后各段)、回肠测定麦芽糖酶、乳糖酶、蔗糖酶的活性。结果表明:补饲对小肠中3种二糖酶活性有一定的影响,补饲组乳糖酶活性在空肠段8,11,15天显著高于其他各天(P<0.05),蔗糖酶活性在空肠前段和中段11,15天显著高于其他各天(P<0.05);非补饲组麦芽糖酶在十二指肠19天、空肠前段19,15,28天显著高于其他各天(P<0.05),乳糖酶活性在十二指肠15天、空肠前段和中段15,11天显著高于其他各天(P<0.05)。说明乳仔猪进行补饲能提前二糖酶发挥高活性的时间;21日龄断奶二糖酶活性对补饲仔猪的影响小于非补饲组;21日龄断奶仔猪比28日龄断奶仔猪酶活性的波动更大;乳仔猪乳糖酶活性在8,11,15日龄达到较高水平。     

施肥对青贮玉米营养品质和饲用价值的影响

为研究施肥种类、施肥量等农业技术措施对青贮玉米营养品质和饲用价值的影响,建立资源节约型的施肥模式,于2008年在河北省石家庄市进行了青贮玉米肥料效应试验.采用再裂区完全随机区组设计,研究底肥(牛粪厩肥和无机复合肥)、种肥(锌肥)和追肥(氮肥)的不同配比与施用量对青贮玉米营养品质和饲用价值的影响.结果表明:1)底肥、种肥...     

CONTRAST ENHANCED SONOGRAPHIC ASSESSMENT OF FEEDING VESSELS AS A DISCRIMINATOR BETWEEN MALIGNANT VS. BENIGN FOCAL SPLENIC LESIONS

Contrast‐enhanced sonography was conducted in 17 confirmed focal splenic lesions (five malignant, 12 benign). Relative echogenicity changes were used for subjective interpretation of lesion perfusion. A rapid influx of contrast agent, resulting in an increased relative echogenicity of the lesion, followed by a rapid clearance of contrast agent was referred to as early washin/early washout. There were 6/12 benign, and 3/5 malignant lesions characterized by early washin/early washout. Therefore, sensitivity, specificity, and accuracy for this parameter in differentiating malignant from benign lesions was 60%, 50%, and 53%, respectively. There were 2/12 benign, and 2/5 malignant lesions with persistent hypoperfusion throughout all phases. Therefore, sensitivity, specificity, and accuracy for malignancy using this criterion were 40%, 83%, and 71%, respectively. However, none of the benign and all malignant lesions were characterized by tortuous and persistently visible feeding vessels. This suggests that interpretation of splenic lesions cannot be performed accurately on the basis of echogenicity or persistent hypoperfusion, but that assessment of vascular tortuosity may be helpful in discriminating between a malignant vs. benign focal splenic lesion.     

双低油菜华协1号青饲效果的研究

双低油菜（Brassica napus)配合玉米秸秆进行的饲养对比试验结果表明：羊只喜食双低油菜，大量食入不会引起腹泻，腹胀等不良反应，与玉米秸秆配合饲喂增重效果极显著高于单饲玉米秸秆（P＜0．01）。供草总量中油菜占50％和20％的羊只，日平均体增重比对照组分别高114．48和85．20g；屠宰率分别提高5．1％和4．3％，净肉率极显著高于对照组（P＜0．01）。油菜占50％比占20％的羊只的净肉率，骨肉比，熟内率和GR值高，而失水率低，由此得出双低油菜作为羊只的主要饲草是可行的。     

对部分瓢虫食性的新发现

七星瓢虫、龟纹瓢虫和异色瓢虫,一直被人们认为是肉食性昆虫。据近年来调查观察,发现这类昆虫一方面可大量捕食蚜虫、介壳虫,另一方面又可严重危害枣花,具有肉食和植食的双重性能。本文还记述了这些瓢虫对枣花的危害情况,并对枣园常见瓢虫进行了检索。     

复合维生素添加量对蛋公雏育肥效果的影响

选用 1日龄健康商品代罗曼蛋公雏 6 0 0只 ,随机分为 3组 ,每组 4个重复 ,进行 70d饲养试验 ,饲喂复合维生素设 3种不同添加水平 ,添加复合维生素 10 0g·t-1(Ⅰ ) ,2 0 0g·t-1(Ⅱ ) ,30 0g·t-1(Ⅲ ) .结果表明 ,提高育肥蛋公雏饲粮中复合维生素的含量能显著提高育肥蛋白雏的健康水平、日增重、饲料转化率及经济效益 .在复合维生素添加量从 2 0 0g进一步增加至30 0g时 ,并不能进一步提高育肥蛋白雏的日增重、饲料转化率和经济效益 ,反而呈下降趋势 .综合日增重、饲料转化率和经济效益 ,育肥蛋白雏饲粮中此复合维生素添加量以 2 0 0g为宜