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11.
选用平均体重29.6kg的三元杂(杜×大×长)生长猪144头,按随机区组设计分为6个处理。饲粮中分别添加0、100、200mg/kg硫酸铜、200mg/kg碱式氯化铜、100mg/kg小肽铜、100mg/kg复合氨基酸螯合铜(以铜含量计)。结果表明:100mg/kg小肽铜和100mg/kg复合氨基酸螯合铜均能有效提高生长猪日增重和日采食量,其促生长效果与200mg/kg硫酸铜无显著(P〉0.05)差异,而粪中铜含量分别下降了36.8%和48.4%(P〈0.05)。 相似文献
12.
An experiment was made to determine the absorption of purine metabolites in dietary nucleic acids through the digestive tract, and also to determine the utilization of nucleic acids absorbed in the body, using growing lambs. Two pairs of 120‐ and 180‐day‐old twin female lambs with a bodyweight of 18.2–19.0 kg were kept in metabolism crates and fed on purine‐free milk replacement (MR) with supplements of exogenous purine (purine base or purine nucleoside) at a level of 0.2 mmol/BW0.75/d for 5 consecutive days, and thereafter they were maintained in the crates for 4 days. The daily amount of exogenous purine supply was calculated based on the urinary excreted purine derivatives (PD) in lambs fed on milk replacement alone. A urine sample was collected daily for 9 consecutive days, and the urinary excretion of PD was determined daily. Urinary PD excretion opened to increase within 24 h after the dose of purine bases, and the level was recovered on 3 days after ceasing the exogenous purine supply. The recovery of PD in the urine was about 70% of the purine supplement. When purine nucleosides were added to the feed, urinary PD excretion was initiated within 24 h after dosing, and the values were recovered after ending the purine nucleoside supply. The recovery rate of PD in the urine was only 30% of the supplemented purine. The plasma allantoin levels were almost similar after feeding purine bases and purine nucleosides, and the values were mostly in the range (40–60 µmol/L). These findings indicate that an exogenous purine can be directly incorporated into the body, and the purine as nucleoside is more effectively utilized for the synthesis of nucleic acids than as a purine base in the body of growing lambs. 相似文献
13.
低蛋白质氨基酸平衡饲粮对生长猪生长性能和氮素减排的影响研究 总被引:1,自引:0,他引:1
试验旨在研究饲喂低蛋白质氨基酸平衡饲粮对生长猪生长性能和氮排泄量的影响,采用单因子完全随机设计,将144头平均体重30 kg左右的杜长大三元杂种生长母猪分成3组,每组设6个重复,每个重复8头猪,对照组饲喂实测粗蛋白质含量为18.10%的普通饲粮,试验1组、试验2组分别饲喂实测粗蛋白质含量为16.08%和14.12%的氨基酸平衡饲粮。试验期37 d,前7 d为预试期,正试期30 d。结果显示,3组日采食量、日增重、料重比指标均没有显著差异(P0.05),而日氮素总排泄量试验1组、试验2组分别比对照组减少18.69%、38.68%,3组之间差异均显著(P0.05),且试验1组、试验2组猪每增重1 kg所需要的饲料成本分别较对照组节省0.11和0.23元。综合考虑,生长猪饲喂低蛋白质氨基酸平衡饲粮,可以作为实现养殖效益与环保双赢的主要技术措施予以推广。 相似文献
14.
15.
Konrad R. Dabrowski 《Fish physiology and biochemistry》1986,1(3):125-144
Oxygen consumption, ammonia excretion and fish swimming speed were measured in fish induced to swim by optomotor reaction in a circular metabolism chamber. The relationship between the swimming speed and fish metabolism described by exponential equations allowed the extrapolation to the standard metabolism, i.e. at zero swimming speed. The partitioning of the catabolised protein in the energy supply was estimated based on AQ (volume of ammonia/ volume of oxygen) values. Weight specific standard metabolism, as expressed by the ammonia excretion rate, decreased by one order of magnitude in coregonids as the fish grew from 20 to 780 mg body weight. The slope of the relationship between oxygen uptake and swimming speed decreased in coregonid ontogenesis. In salmon, after 12 days of fasting 28% of energy used was derived from protein, whilst coregonid juveniles utilized mostly lipid. Active swimming in fasted juveniles of coregonid, as well as in salmon, led to the accelerated utilization of protein as a source of energy, based on AQ coefficients. In juveniles acclimated to a range of water temperatures from 14 to 26°C, the changes in standard or active metabolic rate (expressed as oxygen uptake or ammonia excretion) were described by Q10 coefficients. They were generally higher for the ammonia excretion rate than for the oxygen uptake rate and for active metabolism than for standard metabolism. Utilization of protein as energy for swimming differed significantly between the species, being in general one order of magnitude higher in coregonids than in salmon. The use of protein for swimming activity tended to decrease during coregonid ontogenesis. 相似文献
16.
The impact of feeding, fish size (body weight from 18.5 to 56.5 g) and water temperature (20 and 23 °C) on oxygen consumption (OC, mg O2 kg–1 h–1) and ammonia excretion (AE, mg TAN kg–1 h–1) was studied in Eurasian perch held in recirculation systems. OC for both fed and feed-deprived (3 days) fish was higher at 23 °C (278.5 and 150.1 mg O2 kg–1 h–1) than at 20 °C (249.3 and 135.0 mg O2 kg–1 h–1; P < 0.01). AEs for both fed and feed-deprived fish were also significantly higher at 23 °C than at 20 °C (P < 0.001). Water temperature and fish size had a significant impact on the oxygen:feed ratio (OFR, kg O2 kg–1 feed fed day–1) and ammonia:feed ratio (AFR, kg TAN kg–1 feed fed day–1; P < 0.001). Their average values at temperatures of 20 and 23 °C were 0.17 and 0.19 kg O2 kg–1 feed fed day–1 and 0.009 and 0.011 kg TAN kg–1 feed fed day–1, respectively. 相似文献
17.
[目的]估算了山东省牛粪便的总量及其养分的负荷量和占当年排泄污染物的比例。[方法]根据2010年山东省和各地市牛存栏的行业和统计局两套数据和2012年行业数据,通过计算参数和估算的方法算出了牛粪产生总量。[结果]全省牛粪总共约在7000~9700万 t 之间,占当年所有畜禽粪便产生量的34.07%~37.37%之间,即三分之一以上。德州、济南两市单是牛粪便的土地承载量分别达到了29.7 t/hm2和27.4 t/hm2,接近了欧洲标准30 t/hm2的限量值。[结论]应该引起我们对全省牛业发展方式和发展战略的高度重视。 相似文献
18.
Petra Persson Kristina Sundell Björn Th Björnsson 《Fish physiology and biochemistry》1994,13(5):379-386
Juvenile rainbow trout, Oncorhynchus mykiss, were injected with estradiol-17β (E2) in order to study the source of extra calcium needed during vitellogenesis. E2-treatment increased the calcium uptake from the external medium as well as calcium mobilization from muscle and scale. Judged
by the increase in plasma protein-bound calcium levels, the E2-induced increase in calcium uptake is an apparent over-mobilization of calcium, i.e., the calcium uptake of the fish is in excess of what is found bound to plasma proteins. As the calcium excretion and calcium
space (calculated from free plasma calcium levels) were unaffected, the excess calcium is suggested to be incorporated into
internal calcium stores. This implies that the systems regulating vitellogenesis and calcium balance are integrated on the
mechanistic or endocrine level, and that E2 causes calcium mobilization of a magnitude geared to the needs of the sexually maturing female. 相似文献
19.
20.
Jun M. Zhang 《Animal Science Journal》2014,85(4):435-439
The aim of this study was to determine the effects of dietary supplementation of palygorskite instead of zinc oxide (ZnO) on growth performance, apparent nutrient digestibility and zinc contents in serum and feces in weaned piglets. One hundred and sixty‐five piglets (28 days of age, 7.10 ± 0.86 kg) were allotted to five treatments on the basis of weight and sex. Each treatment included three replicates of 11 piglets. The piglets were fed the same basal diet supplemented with 0 mg/kg (control group), 1800 mg/kg, 2400 mg/kg, or 3000 mg/kg palygorskite or 2500 mg/kg ZnO for 28 days. There was no significant difference for incidence of diarrhea among the four treatments during the 0–14‐day feeding period. Compared with the control group, piglets offered diets supplemented with 1800 mg/kg palygorskite had higher (P < 0.05) average daily gain (ADG) and crude protein digestibility. Fecal digestibility of energy in 1800 mg/kg palygorskite and ZnO groups were higher (P < 0.05) than that in the control group. Both the zinc concentrations in serum and fecal zinc excretion in palygorskite groups and control group were all lower (P < 0.05) than that in the ZnO group. In conclusion, dietary supplementation with 1800 mg/kg palygorskite can improve growth performance and nutrient digestibility and can also decrease zinc excretion in feces in weaned piglets. 相似文献