磷肥施用对水稻生长和磷素吸收的影响

采用田间微区试验研究不同磷肥的施用位置和类型对姜堰、广德两地水稻生长、磷素吸收以及施肥后地表水磷浓度的影响,为水稻根区施磷提供科学依据。磷肥种类为磷酸二氢钙(MCP)和磷酸氢二铵(DAP),施用方式有:1表面撒施;2偏3 cm,深5 cm穴施;3偏12 cm,深5 cm穴施。结果显示施磷对两地水稻均无显著增产,姜堰地区水稻产量显著高于广德。不同施磷位置对水稻吸磷量有显著影响,姜堰、广德两地MCP偏3 cm处理的水稻总吸磷量较MCP偏12 cm处理分别高13%和12%,且DAP偏12 cm处理的水稻总吸磷量显著高于MCP偏12 cm处理,两地增幅分别达到12%和16%,磷肥撒施虽然在水稻分蘖期有较高的吸磷量,但在水稻成熟期不如磷肥偏3 cm穴施。施肥第10天的地表水总磷浓度以磷肥表面撒施处理较高,比磷肥穴施处理分别高245%(姜堰)和94%(广德)。以上结果表明:1适当位置的磷肥穴施不但能够促进水稻对磷的吸收,还能有效缓解径流排水造成的磷流失;2磷酸氢二铵的磷肥适宜施用距离范围较磷酸二氢钙远。     

Effect of partial replacement of dietary monocalcium phosphate with neutral phytase on growth performance and phosphorus digestibility in gibel carp,Carassius auratus gibelio (Bloch)

A feeding trial was conducted to study the effect of partial replacement of dietary monocalcium phosphate (MCP) with neutral phytase on growth performance and phosphorus digestibility in gibel carp, Carassius auratus gibelio (Bloch). Control diet was prepared with 2% MCP but without phytase (P0). Other three experimental diets were prepared by replacement of MCP by 25%, 50% and 75% respectively in comparison with control with supplementation of neutral phytase at 500 U kg^?1 diet in each and designated as P25, P50 and P75 respectively. Gibel carp (initial body weight of 30.22 ± 1.98 g) were reared in twelve 300‐L cylindrical fibreglass tanks provided with filtered flow‐through tap water at 26–28°C. After 8‐week experiment, gibel carp fed with P50 had no obvious differences from the control group on weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency rate (PER) and survival rate. Phytase supplementation did not affect body compositions or muscle compositions. Crude protein and phosphorus (P) contents in the faeces of fish fed with the phytase‐supplemented diets were significantly lower than those of the control group. The apparent digestibility coefficients (ADCs) of crude protein and P in gibel carp were increased when fish fed with the diets in which MCP was replaced by neutral phytase. This study suggested that partial replacement of dietary MCP at 50% with neutral phytase was considered as a recommended dietary supplemental level and increased dietary P and protein availability.     

不同磷源对育肥猪生长性能、血清指标、骨骼钙和磷代谢以及肠道微生物的影响

本试验旨在研究不同磷源对育肥猪生长性能、血清指标、骨骼钙和磷代谢以及肠道微生物的影响.试验选用640头健康的、遗传背景一致、初始体重为(63.10±2.32)kg的"杜×长×大"三元杂交猪,随机分为5个组,每组8个重复,每个重复16头(公母各占1/2).对照组饲喂基础饲粮,磷源为磷酸氢钙(DCP);试验1组磷源为磷酸一...     

湿法磷酸净化制备饲料级磷酸二氢钙新工艺

磷酸二氢钙（MCP）是一种优良的高效性磷酸盐饲料添加剂.本文论述了利用价廉的湿法磷酸,经过两次脱氟、脱硫净化后作为原料,制备低成本饲料级磷酸二氢钙新工艺.     

Effect of monocalcium phosphate supplementation in a low fish meal diet for rainbow trout based on growth,feed utilization,and total phosphorus loading

ABSTRACT:   In order to verify methods for minimizing waste output of phosphorus (P) into the water and preserve an adequate growth rate in rainbow trout, a succession of two feeding trials were performed employing three test diets that were formulated with a low proportion of fish meal (FM), low-P ingredients (defatted soybean meal, corn gluten meal, feather meal, and blood meal), and varying levels of monocalcium phosphate (MCP) as a P supplement (0, 0.5 and 1% of diet which represent 0, 1 and 2 mg/g of available P, respectively). Total P concentrations achieved were 6.2, 8.7 and 9.6 mg/g, respectively. A control diet was formulated with FM as the main protein source and without MCP (total P content was 17.0 mg/g). Diets were fed until apparent satiation to duplicate groups of 50 (1.5 g) and 15 fish (147.8 g) during 24 and 14 weeks, respectively. In both cases, the lowest growth was observed in fish fed the basal diet without MCP. The test diet supplemented with 0.5% MCP provided growth and feed performance comparable to that obtained in fish fed the control diet. These results suggest that diets formulated with low-P ingredients should be supplemented with an adequate amount of P in order to meet the fish requirements and reduced diet-related P loading.     

饲料中不同磷水平对黄鳝生长、体成分及部分生理生化指标的影响

为探讨饲料中不同磷水平对黄鳝幼鱼生长、体成分、骨骼矿化及血液生化指标的影响,以商业配方为基础,磷酸二氢钙为磷源[Ca(H2PO4)2],配制磷含量分别为0.67%、0.91%、1.05%、1.29%和1.53%的5种等氮等能饲料。每种饲料投喂3个网箱(1.5 m×2.0 m×1.5 m),每个网箱放养实验鱼[初始体质量(34.4±0.3)g]100尾,进行70 d的养殖实验。结果显示:(1)随着饲料中磷含量从0.67%增加到1.05%,黄鳝幼鱼各组增重率(WGR)、蛋白质效率(PER)和饲料效率(FE)显著升高(P0.05),当磷含量高于1.05%后各指标进入平台期。折线模型分析[Y=104.67-46.07(1.10-X),R2=0.944]显示,当饲料中磷含量为1.10%时可满足黄鳝生长需要;(2)随着饲料中磷含量的增加,实验鱼体的粗蛋白含量和肥满度显著升高(P0.05),而粗脂肪含量和肝体比显著下降(P0.05);(3)饲料磷含量增加,可显著提高实验组全鱼灰分和全鱼磷含量(P0.05)。折线模型分析[Y=0.988-0.635 4(1.05-X),R2=0.928]显示,当饲料中磷含量为1.05%时可满足黄鳝全鱼磷累积需要;饲料磷含量增加也显著提高了脊椎骨钙和磷含量(P0.05),但脊椎骨钙磷比无显著差异。折线模型分析[Y=7.696-0.985 5(1.10-X),R2=0.956]显示,当饲料中磷含量为1.10%时可满足黄鳝脊椎磷累积需要;(4)饲料磷水平对血清中的磷和钙含量以及碱性磷酸酶活性有显著影响(P0.05)。研究表明,在本实验条件下,饲料中磷含量为1.10%,可以满足黄鳝对磷最大的组织储存需要以及最佳的生长效果。     

Optimum level of dietary monocalcium phosphate determined based on optimal growth and vertebrae phosphate content of juvenile Ussuri catfish,Pseudobagrus ussuriensis

Two experiments were conducted to determine the optimum level of dietary available phosphorus from monocalcium phosphate for juvenile Ussuri catfish Pseudobagrus ussuriensis. Experiment 1 was conducted to estimate phosphorus digestibility from monocalcium phosphate for juvenile Ussuri catfish. The apparent digestibility coefficient of phosphorus from monocalcium phosphate was 86.3%. In the experiment 2, triplicate groups of juvenile Ussuri catfish were fed diets containing graded levels of monocalcium phosphate (MCP: 0 g/kg, 8.2 g/kg, 16.4 g/kg, 24.6 g/kg, 32.8 g/kg and 41.0 g/kg) for 8 weeks. Fish fed the diet containing 16.4 g/kg MCP with available phosphorus of 4.8 g/kg showed the best weight gain (171.5%), feed conversion ratio (1.08) and protein efficiency ratio (2.06). No significant difference was observed in fish survival among the treatments. The best result in terms of phosphorus retention efficiency (46.10%) was observed in fish fed the diet containing 8.2 g/kg MCP with available phosphorus of 3.0 g/kg, which was not different (p > .05) from those fed the diet containing up to 24.6 g/kg MCP, and the highest vertebrae phosphorus content (58.2 g/kg) was observed in fish fed the diet containing 24.6 g/kg MCP with available P of 6.6 g/kg. The whole‐body lipid and protein, as well as phosphorus contents, were significantly affected by dietary available phosphorus (p < .05). Viscerosomatic index (VSI) and condition factor (CF) were inversely correlated with dietary phosphorus levels (p < .05). Quadratic regression analysis based on specific growth rate (SGR) against dietary available phosphorus levels indicated that the optimum available phosphorus requirement for the maximal growth of juvenile Ussuri catfish was 5.9 g/kg, and broken‐line analysis based on vertebrae phosphorus content against dietary available phosphorus levels indicated that a dietary level of 6.0 g/kg available phosphorus will provide optimum vertebrae phosphorus content.     

低磷饲料中补充柠檬酸对大口黑鲈生长和营养物质利用率的影响

为了探究饲料中添加柠檬酸对大口黑鲈（Micropterus salmoides）生长、营养物质利用和氮（N）、磷（P）排放的影响,分别配制磷酸二氢钙（MCP）添加量为5、10（低磷饲料）、15 g/kg （对照饲料）的3组饲料（P5,P10,P15）,在低磷饲料P5和P10中分别添加10 g/kg的柠檬酸,共5组实验饲料。投喂初始体质量为（16.0±0.16） g的大口黑鲈60 d。结果显示,随着MCP添加量的增加,大口黑鲈增重率、全鱼磷含量、粗蛋白沉积率、磷消化率、椎骨磷和血浆磷含量均显著增加（P<0.05）,N排放量和全鱼粗脂肪含量显著下降（P<0.05）,且均在P15组达到最佳水平。在P5饲料中添加柠檬酸,显著提高了鱼体增重率（+5.6%）和血浆磷含量,降低了饲料系数（-0.05）和N排放量（P<0.05）,达到了和P10组基本一致的水平（P>0.05）;在P10饲料中添加柠檬酸,在数值上改善了生长性能（P>0.05）,达到了和P15组基本一致的水平（P>0.05）。此外,在P5和P10饲料中补充柠檬酸,均显著提高了磷消化率,降低了P排放量（P<0.05）。综上所述,在低磷饲料中添加10 g/kg的柠檬酸可改善大口黑鲈生长、提高饲料和磷的利用率。     

Interaction of NPK fertilizers during their transformation in soils: Ⅲ. Transformations of monocalcium phosphate

Interactions of N, P and K fertilizers in soil-plant systems are widely recognized. This study focused on the transformations of monocalcium phosphate (Ca(H2PO4)2) (MCP) with co-application of ammonium and potassium fertilizers in three different soils. The results showed that after 1 d incubation a large portion of the MCP applied in the paddy,calcareous and red soils became the water-insoluble form and the recoveries of P applied as Olsen P varied greatly in these three soils. Application of ammonium sulfate ((NH4)2SO4) (AS) or potassium chloride (KC1) reduced WSP significantly in the soils with AS more effective than KC1 in the calcareous soil, while the reverse occurred in the red soil. Meanwhile, in the paddy soil, co-application of the two fertilizers reduced WSP more than when the fertilizers were applied individually. The co-application of AS with MCP in the paddy and calcareous soils significantly reduced Olsen P, but the opposite occurred in the red soil. The experiment on the effect of different accompanying anions showed that the ammonium fertilizers (PNC1 and PNS) reduced WSP more effectively than the corresponding potassium fertilizers (PKC1 and PKS) in the calcareous soil due to the difference of the cations, whereas in the red soil, the chlorides reduced WSP more effectively than the sulfates. Overall, co-application of ammonium or potassium fertilizers with MCP significantly decreased availability of P from MCP during its transformation in soils, especially when MCP was applied in combination with ammonium in the calcareous soil.