不同生长期金荞麦营养成分含量及消化率测定研究

为系统地测定分析不同生长期金荞麦的常规营养成分、氨基酸、微量元素含量及其回肠末端消化率,本研究用3头安装"T"型瘘管,并做回-直肠吻合切除盲肠的巴克夏-驯养野猪-高坡黑猪(巴-野-高)三元杂交生长猪作为试验动物,采用3×3拉丁方试验设计开展消化试验。结果表明,分枝期、孕蕾期和初花期金荞麦OM、CP、EE、Ca、P、CF含量分别为88.59%、22.72%、2.34%、1.05%、0.39%、13.51%,89.10%、20.57%、1.69%、1.25%、0.42%、15.50%和89.63%、17.54%、1.37%、1.29%、0.46%、19.75%;EAA、NEAA和TAA含量分别为9285、7982、6244mg/100g,14334、10810、9320mg/100g和23619、18792、15564mg/100g。随着生长期的后延,营养成分含量显著降低,在体和离体消化率也随着生长期的后延而显著降低。分枝期与孕蕾期间营养成分含量差异显著(P0.05),分枝期与初花期间营养成分含量差异极显著(P0.01),孕蕾期与初花期间营养成分含量差异显著(P0.05)。从分枝期到孕蕾期,金荞麦CP、EE、EAA及TAA下降较慢,CF含量升高较慢,营养成分消化率下降也较慢;从孕蕾期到初花期,金荞麦CP、EE、EAA及TAA下降较快,CF含量升高也较快,营养成分消化率下降也较快。以分枝期、孕蕾期和初花期体外法测定常规营养成分及微量元素消化率值为自变量,以对应的动物饲养试验回肠末端表观消化率值为因变量建立的回归方程拟合度好,可用于推算对应的回肠末端表观消化率。本实验证明,金荞麦营养丰富、消化率高,必需氨基酸比例高、适合动物消化吸收。孕蕾期为金荞麦适宜收割期,在适宜收割期内,收割时间点应选择孕蕾后期。

Nutrient content and digestibility of Fagopyrum dibotrys at various growth stages

This study investigated the nutritive value,when fed to pigs,of Fagopyrum dibotrys at various growth stages.Crude protein (CP),amino acid (AA),trace element levels,among other parameters,and their digestibility characteristics within the terminal ileum were studied.Three growing Ba×Wild×Gao pigs, and having had an ileo-rectal anastomosis operation with a T fistula installed,underwent a 3 ×3 Latin square trial.The levels of organic matter (OM),CP,ether extract (EE),Ca,P,and crude fiber (CF)in F .dibotrys were 88.59%,22.72%,2.34%,1.05%,0.39%,and 13.51%,respectively,in the branching stage;were 89.10%,20.57%,1.69%,1.25%,0.42%,and 15.50%,respectively,in the bud stage,and were 89.63%, 17.54%,1.37%,1.29%,0.46%,and 19.75%,respectively,in the early flowering stage.Essential amino acid (EAA),non-essential amino acid (NEAA),and total amino acid (TAA)contents in F .dibotrys were 9285,7982,and 6244 mg/100 g,respectively,in the branching stage,were 14334,10810,9320 mg/100 g,re-spectively,in the bud stage,and were 23619,18792,15564 mg/100 g,respectively,in the initial bloom stage. Generally,nutritive value and digestibility characteristics of F .dibotrys decreased with increasing maturity (P <0.05),except for CF which increased.Specifically,the nutrient content and digestibility characteristics were significantly lower at the bud stage than at the branching stage (P <0.05 ),while the decline by early flowering was extremely significant (P <0.01).A gradual decline with increasing crop maturity was observed for CP,EE,EAA,TAA content and digestibility characteristics between the branching and the bud stages,a-gain associated with an increase in CF;a comparatively faster rate of decrease was observed for nutrient content and digestibility characteristics between the bud and early flowering crop maturity stages.Three regression e-quations were developed to describe the relationship between in vitro digestibility values and the corresponding in vivo digestibility values for the three tested maturity states of F .dibotrys .In summary,F .dibotrys has high feeding value in terms of nutrient content,digestibility characteristics,and AA composition.Harvesting is recommended during the bud stage for F .dibotrys for maximum yield of total digestible nutrients.Regres-sion equations developed in the present study can predict in vivo digestibility characteristics of F .dibotrys from in vitro data.