| Four experiments were conducted to investigate the forage value and the prospect of utilizing Alhagi sparsifolia Shap as forage. Experiment 1 evaluated the effects of different stages of maturity on A.sparsifolia silage quality and estimated the appropriate cutting stage for silages. Experiment 2 evaluated the effects of full blooming A. sparsifolia Shap and alfalfa mix-ensiling on silage quality and estimated the optimum proportion of their mix-ensiling. Experiment 3 evaluated the associative effects of mix- silages and estimated the utilization capacity of animal by analyzing in vitro degradation characteristics of full blooming A.sparsifolia Shap and alfalfa mix-silage. Experiment 4 evaluated the palatability, rumen fermentation parameters, routine blood, and blood biochemical indicators,digestibility and average daily gain in a feeding experiment, and provided an objective theoretical basis for the rational utilization of A. sparsifolia Shap.Experiment 1, Budding stage (LF), initial flowering (LC), full blooming (LS), and podding stage (LJ) A. sparsifolia were used in this experiment. After 150 d of ensiling, silages were sensorially evaluated and sampled. Chemical components were evaluated in both fresh grass and silages. All silages were analyzed for fermentation products. The chemical components were significantly different among the different stages of maturity (P < 0.05). Water soluble carbohydrates (12.73%) and crude protein (16.88%) were highest in LS (P < 0.05). The pH (3.65) and NH3-N/TN (1.03%) in LS were lowest among the 4maturity stages. Lactic acid concentration between LS (6.06%) and LJ(6.23%) was not significantly different (P > 0.05) and was higher (P < 0.05) compared to LF (2.59%)and LC (3.19%). Acetic acid concentration was significantly different (P <0.01) among the different stages of maturity of A .sparsifolia silages, and it was significantly higher (P < 0.01) in LC (2.04%)and lower (P < 0.01) in LJ (0.71%). Butyric, isobutyric, valeric, and isovaleric acids concentration were either not detected or detected only in traces in all silages. A comprehensive evaluation showed full blooming (LS) was the appropriate cutting stage for ensiling.Experiment 2,100% alfalfa (M), 100% A.sparsifolia Shap (LS) ,30% A.sparsifolia Shap+70%alfalfa (LS3), 50% A.sparsifolia Shap +50% alfalfa (LS5), and 70% A.sparsifolia Shap +30% alfalfa(LS7) were used in this experiment. Five experimental treatments were designed with 3 replicates per treatment. After 90 d of ensiling, silages were sampled and sensory quality and fermentation products were evaluated. The dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined in both fresh forages and silages. The results showed that DM,water soluble carbohydrates (WSC) were higher in mixed fresh forages than in alfalfa. Lactic acid concentration in treatment LS3, LS5, LS7 was 3.86, 5.64 and 6.75%, respectively, with lower concentration (3.54%) in treatment M. Acetic acid (AA) concentration in treatment LS3, LS5 and LS7 was 1.90, 1.68 and 1.60%, respectively which were higher (P<0.05) than in 100% A. sparsifolia Shap silage (1.32%). The NH3-N/TN in treatment LS3, LS5, LS7 was 9.26, 2.19 and 1.35%, respectively and lower (P<0.05) than in 100% alfalfa silage (11.38%). Similarly, the pH values were 3.84, 3.80 and 3.72 for treatment LS3, LS5 and LS7, respectively, but lower than in 100% alfalfa silage (4.35).Propionic acid (PA), butyric acid (BA), Valeric, methanol (P < 0.01), acetic acid (AA) and ethanol content (P < 0.05) were lower in mixed silages (LS3, LS5 and LS7) compared to 100% alfalfa silage.The total number of lactic acid bacteria living cells in treatment LS3, LS5 and LS7were 7.56, 8.62 and 9.65 log cfu/g, while Bacillus subtilis were 3.02, 4.09, 4.45 log cfu/g and Rhodotorula mucilaginosa were 0.8, 1.15, 1.45 log cfu/g, respectively. On the other hand, the total number of lactic acid bacteria( 5.76 log cfu/g ), B. subtilis ( 2.30 log cfu/g ) and R. mucilaginosa ( 0.03 log cfu /g ) in 100% alfalfa (treatment ?) silage were lower (P < 0.05). A comprehensive evaluation showed that the optimal proportion of mix-ensiling was 70% A. sparsifolia Shap +30% alfalfa.Experiment 3, The objectives of this experiment were to evaluate the degree to which full blooming A.sparsifolia Shap and initial flowering alfalfa mix-silages can be utilized. Alfalfa hay(treatment ? ) ,100% A. sparsifolia Shap (treatment ?) , 30% A. sparsifolia Shap+70% alfalfa(treatment ?) , 50% A. sparsifolia Shap+50% alfalfa, (treatment ?) ,10% A. sparsifolia Shap+30% alfalfa (treatment ? ) were used in this experiment. Gas production was recorded after 2, 4, 8,12, 24, 36, 48, 72 and 96 h incubation. Gas production parameters, in vitro organic matter digestibility(IVOMD) and associative effects were estimated after 24 h of incubation. The results showed that the gas productions in mix-silages for treatment ?, ?, ? was 10.00, 20.00 and 23.00ml, respectively,and was lower (P<0.05) than in treatment ? (28.00ml) and treatment ?(24.00ml) after 24 h incubation. The pH value of in vitro fermentation liquor for treatment ?, ?, ? was 6.47, 6.53,6.57, within the normal range (6-7) and higher than 6.2. Ammonia-N of treatment ?,?,V was 20.41, 19.47 and 18.65 mg/dL, respectively. The optimal concentration range of rumen ammonia-N(85?300mg/L) within the normal range, indicating that there were no adverse effects on the protein utilization by mixed silages. The IVOMD of treatment ?, ?,?was 31.53, 32.56 and 33.75%,respectively, which were lower (P < 0.05) compared to treatment ? (35.23%) and ? (34.79%).Total volatile fatty acids (TVFA) concentration of treatment ?, ?,? were 61.30, 60.50 and 57.10 mmol/L, which were higher (P < 0.05) compared to treatment ? (52.00 mmol/L) and ? (50.00 mmol/L). A comprehensive evaluation showed that in vitro degradation in treatment ? was better than ?, while ? was better than ?.Experiment4 This study was conducted to determine the effects of mix-silages on palatability,apparent digestlbility, average daily gain, rumen fermentation parameters, routine blood indices,blood biochemical indicators and provide an objective theoretical basis for the rational utilization of A.sparsifolia Shap in feeding Daolang sheep. Alfalfa hay ( treatment ? ), 100% A. sparsifolia Shap(treatment ?), 30% A. sparsifolia Shap +70% alfalfa (treatment ?), 50% A. sparsifolia Shap +50%alfalfa (treatment ?) , 70% A. sparsifolia Shap +30% alfalfa (treatment ?) were used in this experiment. The Daolang sheep mix-ensilage intake in treatment ?, ?, ? was 15.82, 19.24 and 11.66 g/min, respectively, and was higher (P < 0.05) than in treatment ?(9.86 g/min). This implied that mix-ensiling could improve the palatability of A. sparsifolia Shap. The apparent digestibility of DM?OM?CP?NDF?ADF between treatment ?,?, ? and V was not significantly different (P>0.05) . This implied that mix-ensiling could not effect apparent digestibility of A. sparsifolia Shap.The pH and ammonia-N in rumen fluids among the 5 treatments were within the normal range. Acetic acid concentration was significantly altered (P<0.01) with treatment IV having the highest (75.70 mmol/L) concentration among the 5 treatments. Propionic acid concentration in treatment ?, ?,?were 49.30, 38.10, and 35.70 mmol/L, respectively and was significantly higher than in alfalfa hay(33.00mmol/L) and A.sparsifolia Shap silage (31.90 mmol/L). Butyric acid concentration was 18.30,21.40 and 18.80 mmol/L in treatment ?, ?, V respectively, and was significantly higher (P <0.05) than in alfalfa hay (17.10mmol/L). The TVFA was higher (P < 0.05) in treatment ?(135.40mmol/L) compared to the other 4 treatments. Although the concentration of blood glucose(Glu), urea, uric acid, creatinine (CR), alanine aminotransferase (ALT), aspertate aminotransferase(AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), albumin (Alb), globulin(GLB), A/B, total bilirubin and indirect bilirubin were not significantly different among groups (P>0.05) , they were within the normal range. The routine blood indices were similar among the groups(P > 0.05) and within the normal range, except for lymphocytes numbers which were higher (P < 0.05)in A. sparsifolia Shop silage compared to alfalfa hay group. Creatinine (CR) concentration was significantly higher in treatment ? (94.60 umol/L) than in treatment ?(77.00umol/L). The ALT was higher (P < 0.05) in treatment ? (28.40U/L) compared to treatment ? (20.60U/L) and the ratio of ALT/AST was significantly lower (P < 0.05) in treatment I (3.78) than in treatment ? (6.64).Total protein (TP) concentration was significantly higher (P < 0.05) in treatment V (81.90g/L)compared to treatment ? (64.28g/L). Direct bilirubin (DB) concentration was significantly higher(P < 0.05) in treatment ? (2.56 umol/L) than in treatment V (1.50 umol/L). Mix-silages did not have a negative effect on liver, kidney and heart functions, energy metabolism and protein metabolism.Comprehensive evaluation revealed that feeding 50% A. sparsifolia Shap +50% alfalfa silage had the optimal results among the 3 mix-silages. |
PDF Full Text Request