Long-Term Animal Feeding Trial of the Refined Konjac Meal Ⅰ. Effects of the Refined Konjac Meal on the Calcium and Phosphorus Metabolism and the Bone in Rat

Effects of refined konjac meal (RKM) on the calcium and phosphorus metabolism and bone parameters were observed in rats of both sexes fed with food containing 1% of RKM for 18 months. A comparable group of rats fed on basic diet only was used as a control.Results obtained indicate that all the measured parameters (serum calcium and phosphorus level, femur weight and its calcium and phesphorus content, and the osteometry of the tibia) showed no significant difference between the experimental and the control groups.Thus there is no adverse effect either on the calcium and phosphorus metabolism or on the bone after a long-term intake at a moderate dosage.

Twice-split phosphorus application alleviates low-temperature impacts on wheat by improved spikelet development and setting

Extreme low-temperature incidents have become more frequent and severe as climate change intensifies.In HuangHuai-Hai wheat growing area of China,the late spring coldness occurring at the jointing-booting stage(the anther interval stage)has resulted in significant yield losses of winter wheat.This study attempts to develop an economical,feasible,and efficient cultivation technique for improving the low-temperature(LT)resistance of wheat by exploring the effects of twice-split phosphorus application(TSPA)on wheat antioxidant characteristics and carbon and nitrogen metabolism physiology under LT treatment at the anther interval stage using Yannong 19 as the experimental material.The treatments consisted of traditional phosphorus application and TSPA,followed by a-4℃ LT treatment and natural temperature(NT)control at the anther interval stage.Our analyses showed that,compared with the traditional application,the TSPA increased the net photosynthetic rate(P_(n)),stomatal conductance(Gs),and transpiration rate(T_(r))of leaves and reduced the intercellular carbon dioxide concentration(C_(i)).The activity of carbon and nitrogen metabolism enzymes in the young wheat spikes was also increased by the TSPA,which promoted the accumulation of soluble sugar(SS),sucrose(SUC),soluble protein(SP),and proline(Pro)in young wheat spike and reduced the toxicity of malondialdehyde(MDA).Due to the improved organic nutrition for reproductive development,the young wheat spikes exhibited enhanced LT resistance,which reduced the sterile spikelet number(SSN)per spike by 11.8%and increased the spikelet setting rate(SSR)and final yield by 6.0 and 8.4%,respectively,compared to the traditional application.The positive effects of split phosphorus application became more pronounced when the LT treatment was prolonged.

Effect of dietary calcium or phosphorus deficiency on bone development and related calcium or phosphorus metabolic utilization parameters of broilers from 22 to 42 days of age

This experiment was conducted to investigate the effect of dietary calcium(Ca)or phosphorus(P)deficiency on bone development and related Ca or P metabolic utilization parameters of broilers from 22 to 42 days of age based on our previous study,which indicated that dietary Ca or P deficiency impaired the bone development by regulating related Ca or P metabolic utilization parameters of broilers from 1 to 21 days of age.A total of 504 one-day-old Arbor Acres male broilers were randomly assigned to 1 of 4 treatments with 7 replicates in a completely randomized design,and fed the normal control and Ca-or P-deficient diets from 1 to 21 days of age.At 22 days of age,the broilers were further fed the normal control diet(0.90%Ca+0.35%non-phytate P(NPP)),the P-deficient diet(0.90%Ca+0.18%NPP),the Ca-deficient diet(0.30%Ca+0.35%NPP)or the Ca and P-deficient diet(0.30%Ca+0.18%NPP),respectively.The results showed that dietary Ca or P deficiency decreased(P<0.05)tibia bone mineral density(BMD),bone breaking strength(BBS),ash content,tibia ash Ca content and serum P content on days 28 and 42,but increased(P<0.05)tibia alkaline phosphatase(ALP)activity of broilers on day 42 compared with the control group.Furthermore,the broilers fed the P-deficient diet had the lowest(P<0.05)tibia BMD,BBS,ash content,serum P content and the highest(P<0.05)serum Ca content on day 28 compared with those fed the Ca-deficient or Ca and P-deficient diets.The results from the present study indicated that the bone development and related Ca or P metabolic utilization parameters of broilers were the most sensitive to dietary P deficiency,followed by dietary Ca deficiency or Ca and P-deficiency;dietary Ca or P deficiency impaired the bone development possibly by regulating serum Ca and P contents as well as tibia Ca content and ALP activity of broilers from 22 to 42 days of age.

Macronutrients Uptake in Soybean as Affected by <i>Bradyrhizobium japonicum</i>Inoculation and Phosphorus (P) Supplements

Field and glasshouse experiments were conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on macronutrient uptake by soybean. The treatments consisted of B. japonicum inoculation (with & without), phosphorus supplementation at the levels of 0, 20, 40 and 80 kg P·ha-1. Both treatments were replicated four times in a split plot design. The macronutrients considered were N, P, K, Ca and Mg. Results showed that inoculation with B. japonicum significantly contribute to the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole soybean plant. Likewise, phosphorus supplementation significantly enhanced the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole plant. The use of effective strains of rhizobia and P supplementation was an effective way of enhancing the growth of soybean, eventually the uptake of macronutrients in plant organs.

Correlations between delayed fluorescence of chlorophyll, metabolism and yield of plants. I. Influence of fertilizers on correlations

The increase of the potash fertilizer dose in-duced a raise in efficiency influence of the ni-trogen fertilizer, optimisation of phosphorous fertilizer effect, enhancement of leaf protein production, expansion of assimilating surface and yield growth. In the period of yield forma-tion, the parameters of delayed fluorescence of chlorophyll (DF) of leaf wholly corresponded with key factors that had a dramatic influence on the effectiveness of yield formation. The maximum level of DF amplitude mostly de-pended on the activity of nitrogen metabolism and presumably on active PSII concentration changes per square unit. Half-decay time of this amplitude was predominantly identified by the level of carbohydrate metabolism in the overall plant system, including the quantity of its products and, therefore, mostly by correspon-dence with yield. This is a biological base trig-gering the use of DF parameters for system analyses of plant production process.

Cottonseed yield and its quality as affected by mineral fertilizers and plant growth retardants

The increase in the population in Egypt makes it imperative to explore promising approaches to increase food supply, including protein and oil, to meet the needs of the Egyptian people. Cotton is the principal crop of Egyptian agriculture, it is grown mainly for its fiber, but cottonseed products are also of economic importance. Cottonseed is presently the main source of edible oil and meal for livestock in Egypt. Economic conditions in modern agriculture demand high crop yields in order to be profitable and consequently meet the high demand for food that comes with population growth. Oil crop production can be improved by development of new high yielding varieties, and the application of appropriate agronomic practices. There is limited information about the most suitable management practice for application of N, P, K, Zn, Ca and PGRs in order to optimize the quantity and quality of oil and protein of cottonseed. In maximizing the quantity and quality of a crop’s nutritional value in terms of fatty acids and protein, field experiments were conducted to investigate the effect of nitrogen, phosphorus, potassium, foliar application of zinc and calcium, the use of plant growth retardants (Pix, Cycocel or Alar), on cottonseed, protein, oil yields, and oil properties of Egyptian cotton. From the findings of this study, it seems rational to recommend that application of N, P, K, foliar application of Zn and Ca, the use of PGRs (Pix, Cycocel or Alar), could bring about better impact on cottonseed yield, seed protein content, oil and protein yields, oil refractive index, unsaponifiable matter, and unsaturated fatty acids in comparison with the ordinary cultural practices adopted by Egyptian cotton producers.

日粮添加木聚糖酶对肉牛生长性能、氮钙磷代谢的影响

文章旨在研究日粮中添加木聚糖酶对肉牛营养物质氮、钙和磷代谢的影响,试验将80头身体健康且饲养背景相同的肉牛随机分为4组,每组4个重复,每个重复5头,分别饲喂添加0mg/kg(对照组)、100mg/kg(T1组)、200mg/kg(T2组)、300mg/kg(T3组)木聚糖酶的基础日粮,试验结果表明,(1)与对照组相比,随着木聚糖酶添加量的增加,肉牛末重持续升高,各处理间差异显著(P<0.05);T3组日平均增重显著高于T1组和对照组(P<0.05);(2)与对照组相比,各处理食入氮、粪氮、尿氮、食入钙、粪钙、食入磷、粪磷、氮保留量、钙保留量、磷保留量呈持续上升趋势(P<0.05);T1组尿钙含量显著高于其他处理(P<0.05);T3组尿磷含量显著低于其他处理(P<0.05)。综上所述,日粮中添加木聚糖酶能增加食入氮钙磷、粪中氮钙磷、尿中氮含量,表明木聚糖酶可通过促进肉牛氮钙磷代谢而提高生长性能,以300mg/kg添加量效果最佳。

Direct and residual effects of plant nutrition’s and plant growth retardants, on cottonseed

Seed quality is one of the most important factors for stand establishment in cotton (Gossypium Sp.), and the use of good-quality seeds is therefore essential to obtain an optimum plant population. Conditions prevailing during seed formation can affect the quality of seed produced, and hence crop establishment in the next growing season. These conditions can affect the germination of the seeds and the ability of the seedlings to emerge from soil. Field experiments were conducted to investigate the effect of nitrogen (N), phosphorus (P), potassium (K), foliar application of zinc (Zn) and calcium (Ca), and the use of plant growth retardants (PGR) [e.g., 1, 1-dimethyl piperidinium chloride (MC);2-chloroethyl trimethyl ammonium chloride (CC);or succinic acid 2, 2-dimethyl hydrazide (SADH)], during square initiation and boll setting stage, on growth, seed yield, seed viability, and seedling vigor of Egyptian cotton (G. barbadense). Dry matter yield, total chlorophyll concentration, K, Zn and P-uptake plant-1, were increased with the addition of K, foliar application of Zn, and different concentrations of P (576-1728 g·ha-1 of P). Seed yield plant-1 and plot-1, seed weight, seed viability, seedling vigor, and cool germination test performance increased as a result of the addition of the high N-rate (142.8 kg·ha-1 N), the high P-rate (74 kg·ha-1 P2O5), K (47 kg·ha-1 K), and from application of Zn, and Ca and the PGR. From the findings of the present study, band application of such treatments showed improved cotton-seed yield and affected the quality of seed produced, and hence crop establishment in the next growing season.

Metabolic bone disease in the preterm infant: Current state and future directions

Neonatal osteopenia is an important area of interest for neonatologists due to continuing increased survival of preterm infants. It can occur in high-risk infants such as preterm infants, infants on long-term diuretics or corticosteroids, and those with neuromuscular disorders. Complications such as rickets, pathological fractures, impaired respiratory function and poor growth in childhood can develop and may be the first clinical evidence of the condition. It is important for neonatologists managing such high-risk patients to regularly monitor biochemical markers for evidence of abnormal bone turnover and inadequate mineral intake in order to detect the early phases of impaired bone mineralization. Dual-energy X-ray absorptiometry has become an increasingly used research tool for assessing bone mineral density in children and neonates, but more studies are still needed before it can be used as a useful clinical tool. Prevention and early detection of osteopenia are key to the successful management of this condition and oral phosphate supplements should be started as soon as is feasible.

钙离子对盐胁迫小麦幼苗氮代谢的影响

为探讨增强小麦抗盐能力的调控途径,以普通小麦豫麦34为材料,研究了Ca2+对盐胁迫下小麦幼苗氮代谢及生长的影响。采用全营养液培养小麦幼苗至第一片叶完全展开,更换无钙营养液,并开始不同处理。处理分别为低盐胁迫(150mmo.lL-1NaCl)、低盐胁迫+4 mmol.L-1Ca2+、高盐胁迫(300 mmol.L-1NaCl)、高盐胁迫+4mmo.lL-1Ca2+,以无NaCl胁迫的小麦为对照。5 d后取样,测定了氮同化酶活性、代谢物含量、积累量及幼苗生长状况。结果表明,Ca2+明显缓解了低盐胁迫对小麦幼苗的生长抑制,表现在鲜重、叶绿素及可溶性蛋白含量的增加,而对高盐胁迫下小麦幼苗的生长无明显改善效果;Ca2+改善了低盐胁迫下小麦幼苗的氮营养状况,表现在氮积累量的增加,这一效应主要是通过硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及异柠檬酸脱氢酶(NADP-ICDH)活性的增强而实现的。Ca2+未能改善高盐胁迫下小麦幼苗氮营养状况的主要限制因子在于NADP-ICDH活性未明显增加。

饲粮不同磷水平和钙磷比对育成期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响

本试验旨在研究饲粮不同磷水平和钙磷比对育成期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响。选取70日龄体重相近的雌性水貂90只,随机分为9组,每组10个重复,每个重复1只。采用3×3双因子试验设计,设3个磷水平分别为1.0%、1.4%、1.8%,3个钙磷比分别为1.0、1.5、2.0,配制9种试验饲粮,9种试验饲粮的钙、磷水平实测值如下：1.02%钙、0.96%磷（Ⅰ组）,1.49%钙、1.00%磷（Ⅱ组）,1.98%钙、1.01%磷（Ⅲ组）,1.47%钙、1.35%磷（Ⅳ组）,2.11%钙、1.40%磷（Ⅴ组）,2.81%钙、1.40%磷（Ⅵ组）,1.83%钙、1.73%磷（Ⅶ组）,2.70%钙、1.80%磷（Ⅷ组）,3.59%钙、1.80%磷（Ⅸ组）。预试期7 d,正试期60 d。结果表明：1）饲粮磷水平对育成期水貂的末重、平均日增重有极显著影响（P〈0.01）,对平均日采食量、料重比有显著影响（P〈0.05）。饲粮钙磷比只对育成期水貂的平均日增重有极显著影响（P〈0.01）,对末重、平均日采食量和料重比的影响不显著（P〉0.05）。饲粮磷水平与钙磷比对育成期水貂的平均日增重有极显著交互作用（P〈0.01）。Ⅴ组的末重、平均日增重最大,料重比最小。2）育成期水貂蛋白质消化率差组间差异显著（P〈0.05）,具体表现为Ⅴ、Ⅵ、Ⅷ组显著高于Ⅰ组（P〈0.05）,同时Ⅴ、Ⅵ组还显著高于Ⅲ组（P〈0.05）。饲粮磷水平极显著影响育成期水貂的蛋白质消化率（P〈0.01）。饲粮钙磷比对育成期水貂各营养物质消化率的影响不显著（P〉0.05）,但脂肪消化率有随饲粮钙磷比的升高呈先增加后降低的二次变化趋势。3）氮沉积表现为Ⅵ组显著高于Ⅰ和Ⅷ组（P〈0.05）,净蛋白质利用率表现为Ⅵ、Ⅶ、Ⅸ组极显著高于Ⅱ和Ⅷ组（P〈0.01）,蛋白质生物学价值以Ⅸ组最高,但与Ⅵ和Ⅶ组差异不显著（P〉0.05）。粪氮含量有随饲粮磷水平的升高而下降的趋势,净蛋白质利用率、蛋白质生物学价值有随饲粮磷水平的升高而增加的趋势。饲粮钙磷比对净蛋白质利用率、蛋白质生物学价值有极显著影响（P〈0.01）。4）粪钙、粪磷含量及钙、磷消化率组间存在极显著差异（P〈0.01）,以Ⅸ组粪钙、粪磷含量最高,Ⅵ组钙消化率最高,Ⅶ组磷消化率最高。饲粮磷水平、钙磷比对育成期水貂粪钙、粪磷含量及钙、磷消化率有极显著影响（P〈0.01）。饲粮磷水平与钙磷比对育成期水貂的粪钙含量、钙消化率有极显著交互作用（P〈0.01）,对粪磷含量有显著交互作用（P〈0.05）。综合各项指标,饲粮中磷水平在1.4%~1.8%、钙磷比在1.5~2.0时,育成期水貂可以获得较好的生长性能及较高的营养物质消化率。

外源钙离子对小麦幼苗氮素代谢的影响

以普通小麦豫麦34为材料,研究了不同浓度的外源Ca2+对小麦幼苗氮素代谢的影响。在小麦第一片叶完全展开后,开始外源Ca2+处理,设0(对照)、2、4 mmo.lL-1和8 mmo.lL-14个Ca2+浓度梯度。处理5d后,测定氮同化酶活性、氮同化量及其它相关代谢物含量。结果表明,小麦幼苗叶片中硝酸还原酶(NR)和谷氨酰胺合成酶(GS)在2 mmo.lL-1Ca2+处理下活性比对照有显著增加,4 mmo.lL-1Ca2+处理的NR活性增加明显,但GS活性增加不显著;8 mmo.lL-1Ca2+处理下NR和GS活性比对照均明显降低。谷氨酸脱氢酶(NADH-GDH)活性在2 mmo.lL-1Ca2+处理下活性增加不明显,而在4、8 mmo.lL-1Ca2+处理下活性显著增加。小麦幼苗氮同化量以4 mmo.lL-1处理最大,2 mmo.lL-1处理与4 mmo.lL-1之间差异不显著;Ca2+浓度为8mmo.lL-1时,氮素同化量明显降低。结果揭示了小麦幼苗不同氮同化途径对Ca2+的响应不同,GS途径比GDH途径对小麦氮素同化量的增加作用更大;4 mmo.lL-1对小麦幼苗的氮素利用可能是最有效的Ca2+浓度。

钙水平对大葱生长及氮代谢的影响

【目的】通过探讨钙对大葱生长及氮代谢的影响,明确钙在提高大葱产量和品质中的作用,为优化大葱施肥技术提供理论依据。【方法】以‘昭和’和‘章丘’大葱为试材,进行了砂培试验和田间试验。用砂培试验营养液钙水平设0、4、6、8 mmol/L 4个处理。于大葱越夏期(7月17日)、叶丛速生期(9月11日)及假茎充实期(10月20日)取大葱叶片测定不同形态氮含量以及硝酸还原酶(NR)、谷氨酰胺合成酶(GS)、谷氨酸合酶(GOGAT)和谷氨酸脱氢酶(GDH)活性,于收获期(11月13日)测定大葱生长量、产量及品质。田间试验设置0、225、450、675 kg/hm^2 4个水平(以Ca O计),于收获期(11月13日)测定产量。【结果】砂培大葱株高、茎粗、根及茎叶鲜重均随营养液钙水平提高而显著增加,至钙水平达6 mmol/L时表现较好,单株生长量达211.13 g,钙水平继续增加至8 mmol/L时,单株生长量仅185.83 g,与4 mmol/L的183.29 g无显著差异;除根系鲜重外,‘章丘’大葱株高、茎粗及茎叶鲜重均显著高于‘昭和’大葱。适量增加钙水平亦可显著提高大葱叶片GOGAT、GDH、NR、GS活性,以叶丛速生期影响最大。大葱叶片铵态氮(NH_4^+-N)、硝态氮(NO_3~–-N)、可溶性蛋白、游离氨基酸含量均随营养液钙水平提高而呈先增加后降低,均以叶丛速生期最高。两品种大葱品质相关指标均以钙水平6 mmol/L时最高,8 mmol/L时有所降低。钙水平为6 mmol/L时,盆栽大葱产量显著高于其它处理,‘章丘’和‘昭和’分别较对照增产79.94%和74.42%。大田试验,‘章丘’和‘昭和’大葱均以施用Ca O 450 kg/hm^2产量最高,分别较对照提高12.30%、19.00%。【结论】适量施钙可显著促进大葱生长,提高叶片氮代谢酶活性及不同形态氮含量,提高产量及品质。综合分析表明,以营养液钙水平6 mmol/L、土壤施钙450 kg/hm^2时最有利于大葱的生长及产量品质的提高。

钙螯合剂对小麦幼苗氮代谢和干物重的影响

营养液中添加钙螯合剂EGTA[Glycol bis (α aminoethyl)etherN ,N ,N′ ,N′ tetraaceticacid ,乙二醇双 (α 氨基乙基 )醚四乙酸 ]导致小麦幼苗干物质累积下降 ,降低地上部和地下部全钙含量 ,抑制小麦幼苗对外源硝态氮的吸收及其向地上部的运输 ,改变其在不同器官中的分配比例和影响其向氨基氮或可溶性蛋白质的转化。叶片和根中硝酸还原酶活性与相应器官中的NO- 3 N含量相关 ,叶片中谷氨酰胺合成酶 (GS)活性在EGTA处理后明显下降 ,根中GS活性变化不显著。

饲粮不同磷水平和钙磷比对冬毛期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响

本试验旨在研究饲粮不同磷水平和钙磷比对冬毛期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响。选取（130±10）日龄体重相近的健康雌性水貂90只,随机分为9组,每组10个重复,每个重复1只。采用3×3双因子试验设计,设3个磷水平分别为1.0%、1.4%、1.8%,3个钙磷比分别为1.0、1.5、2.0,配制9种试验饲粮,9种试验饲粮的钙、磷水平实测值如下：1.03%钙、0.97%磷（Ⅰ组）,1.47%钙、0.98%磷（Ⅱ组）,1.98%钙、0.99%磷（Ⅲ组）,1.45%钙、1.37%磷（Ⅳ组）,2.08%钙、1.38%磷（Ⅴ组）,2.79%钙、1.38%磷（Ⅵ组）,1.81%钙、1.75%磷（Ⅶ组）,2.70%钙、1.79%磷（Ⅷ组）,3.59%钙、1.80%磷（Ⅸ组）。预试期10 d,正试期67 d。结果表明：1）饲粮磷水平和钙磷比以及二者的交互作用极显著影响冬毛期水貂的末重、平均日增重（P〈0.01）。Ⅴ组的末重、平均日增重极显著高于其他组（P〈0.01）。2）干物质、蛋白质、脂肪消化率有随着饲粮钙磷比和磷水平的升高先增加后降低的趋势,且均在Ⅲ组达到最大值。3）饲粮磷水平和钙磷比以及二者的交互作用对冬毛期水貂食入氮、尿氮、粪氮、氮沉积、净蛋白质利用率、蛋白质生物学价值的影响不显著（P〉0.05）。4）随着饲粮磷水平的升高,粪钙含量随之增加,组间差异极显著（P〈0.01）;Ⅷ、Ⅸ组粪钙含量显著或极显著高于除Ⅶ组外的其他各组（P〈0.05或P〈0.01）。随着饲粮磷水平的升高,粪磷含量随之增加,组间差异显著或极显著（P〈0.05或P〈0.01）;饲粮钙磷比为2.0时粪磷含量最低,极显著低于饲粮钙磷比为1.0和1.5时（P〈0.01）;Ⅷ、Ⅸ组粪磷含量显著或极显著高于除Ⅶ组外的其他各组（P〈0.05或P〈0.01）。饲粮磷水平和钙磷比极显著影响钙消化率（P〈0.01）。随着饲粮钙磷比的升高,钙消化率极显著升高（P〈0.01）。Ⅲ组钙消化率最高,极显著高于除Ⅵ和Ⅸ组外的其他各组（P〈0.01）。饲粮磷水平和钙磷比对磷消化率的影响不显著（P〉0.05）,但二者的交互作用对磷消化率有显著影响（P〈0.05）。磷消化率以Ⅰ组最低,Ⅲ组最高。综合各项指标,从降低饲粮成本、保护环境和维持冬毛期水貂生长性能的角度出发,饲粮磷水平在1.4%、钙磷比在1.5-2.0时较为适宜。

钙胁迫对枇杷小苗叶片若干氮代谢指标的影响

枇杷小苗钙营养液沙培试验结果表明:钙胁迫不利枇杷小苗叶片氮代谢的进行,缺钙胁迫在小苗培养60 d时就已经产生影响,而高钙胁迫表现比较滞后,且缺钙胁迫的影响要比高钙处理的大.小苗培养60 d时,0.01 mmol/L、3.2 mmol/L钙胁迫处理会使叶片硝酸还原酶活性增大、O2-净产生速率降低、可溶性蛋白含量增加、脯氨酸含量下降.继续培养至90 d时,3个处理的硝酸还原酶活性都增大、O2-净产生速率上升,胁迫处理对两者的影响与60 d相同;而可溶性蛋白和脯氨酸含量虽急剧下降,但胁迫处理的脯氨酸含量高于对照.小苗培养90 d时,叶片游离氨基酸含量测定结果表明,缺钙处理的游离氨基酸总量和单个氨基酸高于对照,高钙处理低于对照,各处理中单个氨基酸含量最高的是谷氨酸,胱氨酸含量最低.

硝酸钙胁迫对水培嫁接茄子氮碳同化的影响

为了研究Ca(NO3)2胁迫下茄子嫁接苗氮碳同化的生理响应以探讨嫁接茄子的耐盐生理机制,以日本引进的设施栽培专用耐盐砧木品种Torvum Vigor为砧木,栽培品种苏崎茄为接穗,用营养液栽培,对80 mmol/LCa(NO3)2胁迫下茄子嫁接苗和未嫁接苗叶片氮同化和碳同化进行了比较。结果显示:Ca(NO3)2胁迫下,茄子嫁接苗株高和生物量积累均显著高于未嫁接苗;茄子嫁接苗和未嫁接苗叶片NO3-和NH4+含量呈先增加后下降趋势,而嫁接苗在胁迫后期均显著高于未嫁接苗;嫁接苗叶片硝酸还原酶(NR)活性在胁迫9 d后显著高于未嫁接苗;可溶性蛋白含量在胁迫期间均显著高于未嫁接苗;嫁接苗和未嫁接苗叶片谷氨酰胺合成酶(GS)活性呈先上升后下降趋势,而嫁接苗GS活性在胁迫后期显著高于未嫁接苗;嫁接苗叶片可溶性糖含量呈先增加后下降趋势,而未嫁接苗叶片可溶性糖含量呈显著下降趋势,且嫁接苗在胁迫期间均显著高于未嫁接苗;嫁接苗淀粉含量显著高于未嫁接苗,而α、β淀粉酶活性均显著低于未嫁接苗。Ca(NO3)2胁迫下,茄子嫁接苗氮同化和碳同化效率较高,胁迫下仍能保持较好的能量储存和生理代谢机制,进而表现出对Ca(NO3)2胁迫有较强适应性。

饲粮维生素D和钙水平对育成期水貂生长性能、营养物质消化率及氮代谢的影响

本试验旨在研究在钙磷比固定的条件下,饲粮维生素D和钙水平对育成期水貂生长性能、营养物质消化率及氮代谢的影响。选取(60±5)日龄健康短毛黑公水貂117只,随机分成9组,每组13个重复,每个重复1只。试验采用3×3双因素随机试验设计,饲粮钙磷比固定为2,设3个维生素D水平,分别为2 100、4 100、6 100 IU/kg,3个钙水平,分别为2.3%、2.7%、3.1%,共配制9种试验饲粮,9种饲粮的钙与维生素D水平分别为2.3%与2 100 IU/kg(Ⅰ组)、2.3%与4 100 IU/kg(Ⅱ组)、2.3%与6 100 IU/kg(Ⅲ组)、2.7%与2 100 IU/kg(Ⅳ组)、2.7%与4 100 IU/kg(Ⅴ组)、2.7%与6 100 IU/kg(Ⅵ组)、3.1%与2 100 IU/kg(Ⅶ组)、3.1%与4 100 IU/kg(Ⅷ组)、3.1%与6 100 IU/kg(Ⅸ组)。预试期13 d,正试期60 d。结果表明:1)饲粮维生素D和钙水平对育成期水貂的末重、平均日增重、料重比均有极显著的影响(P<0.01),末重、平均日增重均以Ⅷ组最高,Ⅰ组最低,料重比以Ⅷ组最低,Ⅰ组最高。2)育成期水貂脂肪消化率组间差异极显著(P<0.01),Ⅱ、Ⅳ、Ⅴ组极显著高于Ⅶ、Ⅷ组(P<0.01)。饲粮钙水平对育成期水貂干物质排出量有显著影响(P<0.05),以钙水平为3.1%时最高;饲粮钙水平对育成期水貂脂肪消化率有极显著影响(P<0.01),钙水平为3.1%时极显著低于钙水平为2.3%和2.7%时(P<0.01)。饲粮维生素D水平极显著影响育成期水貂的干物质排出量(P<0.01),以维生素D水平为4 100 IU/kg时最低;饲粮维生素D水平显著影响育成期水貂的干物质消化率、脂肪消化率(P<0.05),二者均以维生素D水平为4 100 IU/kg时最高。3)饲粮钙水平对育成期水貂的氮沉积有显著影响(P<0.05),且氮沉积呈现随饲粮钙水平的升高而增加的趋势,以钙水平为3.1%时最高。饲粮维生素D水平对育成期水貂的净蛋白质利用率、蛋白质生物学价值有显著影响(P<0.05),且均以维生素D水平为4 100 IU/kg时最高。饲粮维生素D和钙水平对育成期水貂的净蛋白质利用率、蛋白质生物学价值均有显著的交互作用(P<0.05),二者以Ⅷ组最高。综合各项指标,在本试验条件下,饲粮中钙磷比为2、维生素D水平为4 100 IU/kg、钙水平为3.1%时,育成期水貂可以获得较好的生长性能、较高的营养物质消化率及氮利用率。

日粮维生素D和钙水平对冬毛期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响

本试验旨在研究当日粮钙磷比一定时,维生素D和钙水平对冬毛期水貂生长性能、营养物质消化率及氮、钙、磷代谢的影响。随机选取(135±5)日龄、健康雄性水貂117只,分成9组,每组13个重复,每个重复1只。采用3×3双因素随机试验设计,设3个维生素D水平,分别为2 300、4 300、6 300IU/kg;设3个钙水平,分别为2.0%、2.4%、2.8%,钙磷比固定为1.7∶1,配制9组试验日粮,分别为:Ⅰ组(2 300IU/kg维生素D+2.0%钙)、Ⅱ组(4 300IU/kg维生素D+2.0%钙)、Ⅲ组(6 300IU/kg维生素D+2.0%钙)、Ⅳ组(2 300IU/kg维生素D+2.4%钙)、Ⅴ组(4 300IU/kg维生素D+2.4%钙)、Ⅵ组(6 300IU/kg维生素D+2.4%钙)、Ⅶ组(2 300IU/kg维生素D+2.8%钙)、Ⅷ组(4 300IU/kg维生素D+2.8%钙)、Ⅸ组(6 300IU/kg维生素D+2.8%钙)。预试期13d,正试期60d。结果表明:(1)各组水貂料重比差异极显著(P<0.01),Ⅱ组最低。钙水平对料重比有显著影响(P<0.05),维生素D水平对料重比有极显著影响(P<0.01)。(2)钙水平可极显著影响粗脂肪消化率(P<0.01),其中2.8%水平极显著低于2.0%和2.4%水平(P<0.01)。(3)日粮维生素D和钙水平对水貂氮代谢指标均无显著影响(P>0.05)。(4)各组水貂粪钙、粪磷、钙消化率、磷消化率均差异极显著(P<0.01),其中Ⅱ组钙消化率、磷消化率最高,Ⅲ组次之。钙水平可极显著影响粪钙、粪磷、钙消化率、磷消化率(P<0.01),2.0%水平可极显著降低粪钙、粪磷含量(P<0.01),极显著提高钙消化率及磷消化率(P<0.01)。维生素D水平对钙消化率影响显著(P<0.05),对粪磷、磷消化率影响极显著(P<0.01),2 300～4 300IU/kg维生素D水平有利于提高钙消化率、磷消化率,降低粪磷含量。综合考虑各项指标,在本试验条件下,日粮中钙磷比为1.7∶1,维生素D水平为2 300～4 300IU/kg、钙水平为2.0%时,冬毛期水貂料重比及钙、磷排放量较低,而粗脂肪、钙、磷消化率较高。

日粮添加酮戊二酸对生长肥猪生长性能、氮平衡、钙磷代谢及骨成分的影响

试验旨在研究日粮添加酮戊二酸对生长肥猪生长性能、氮平衡、钙磷代谢及骨成分的影响。选择84 d健康、体重接近[(40.08±0.56)kg]的杜×长×大商品猪80头,随机分成2组,每组5个重复,每个重复8头。采用玉米-豆粕型基础日粮,对照组饲喂基础日粮,试验组饲喂在基础日粮中添加10 kgα-酮戊二酸,试验共进行4周。结果显示:日粮添加酮戊二酸对平均日增重有提高趋势(P=0.08);与对照组相比,酮戊二酸组对猪只平均日采食量和料重比的影响无显著差异(P>0.05)。日粮添加酮戊二酸对生长肥猪氮摄入量无显著影响(P>0.05),但粪氮排泄量有降低趋势(P=0.09),氮沉积量有升高的趋势(P=0.07)。试验组尿氮排泄量、总氮排泄量及氮排泄量显著低于对照组(P<0.05),氮表观消化率及蛋白质利用率显著高于对照组(P<0.05)。对照组与试验组对钙磷摄入量及尿磷排泄量的影响无显著差异(P>0.05);与对照组相比,试验组显著降低了粪磷和粪钙排泄量(P<0.05),钙沉积量有升高趋势(P=0.06);试验组较对照组显著提高了磷沉积量和钙磷表观消化率(P<0.05),显著降低了粪钙和尿钙排泄量(P<0.05)。日粮添加酮戊二酸较对照组显著提高了股骨灰分、磷、钙含量及骨密度(P<0.05),但对照组与试验组对胫骨成分的影响无显著差异(P>0.05)。结果表明,在本试验条件下,日粮添加酮戊二酸可以降低尿氮和总氮排泄量,提高钙磷利用率,同时提高股骨钙磷含量及骨密度。酮戊二酸可以改善生长肥猪氮、钙和磷的代谢和利用率。