蒸汽压片玉米对奶牛生产性能和氮磷排放的影响
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摘要
本试验研究了蒸汽压片玉米对泌乳早期荷斯坦奶牛生产性能、消化代谢、血液生化指标及对氮、磷排放的影响,并提出了本地区典型日粮条件下泌乳早期中国荷斯坦奶牛日粮中蒸汽压片玉米的适宜添加量。
选择8头泌乳早期的经产中国荷斯坦奶牛,随机分为4组,每组2头,试验前各组奶牛日均产奶量、胎次、泌乳天数、体重差异不显著(P<0.05)且健康无疾病。采用4×4重复拉丁方设计。各组实验日粮精粗比一致,其中,A组为对照组(仅饲喂基础日粮),B组、C组和D组为试验组,其精饲料中蒸汽压片玉米含量分别为10%、20%和30%。试验分四期,每期28d。
结果表明:(1)日粮中添加蒸汽压片玉米对奶牛干物质采食量没有显著影响(P>0.05),但显著提高了饲料转化率(奶料比)(P<0.05);(2)日粮中蒸汽压片玉米的添加在不同程度上提高了日粮中养分的表观消化率,但均未达到显著水平(P>0.05);(3)试验组奶牛产奶量和4%FCM产量均显著提高,其中10%组、20%组和30%组奶牛的产奶量分别比对照组提高1.76 kg/d (P>0.05),2.38 kg/d (P<0.05)和2.54 kg/d (P<0.05),但各试验组之间差异不显著(P>0.05);20%组与30%组的4%FCM产量分别比对照组提高2.78 kg/d (P<0.01)和2.87 kg/d (P<0.01),达到了极显著水平;(4)蒸汽压片玉米的添加对乳指标率无显著影响(P>0.05),乳蛋白、乳糖、乳非脂固形物产量显著增加,其中30%组乳脂量和乳蛋白量分别比对照组(1.07 kg/d,0.86 kg/d)提高0.11 kg/d和0.1 kg/d,达到极显著水平(P<0.01);(5)试验组奶牛乳体细胞数分别比对照组降低了8.73%、11.92%和17.88%,但各组差异均不显著(P<0.05);(6)日粮中添加蒸汽压片玉米组奶牛的血糖含量较对照组都有提高,试验各组较对照组分别提高3.92 mg/dL (P>0.05)、6.25 mg/ dL (P<0.05)和6.96 mg/ dL(P<0.01);日粮中添加蒸汽压片玉米可降低奶牛血清游离脂肪酸的含量,试验各组较对照组分别降低23.92 mg/dL (P<0.01)、29.84 mg/dL (P<0.01)和38.93 mg/dL (P<0.01),其中30%组和10%组之间也存在显著性差异(P<0.05);日粮添加蒸汽压片玉米可降低奶牛血清尿素氮(BUN)的含量,其中20%、30%两组比对照组BUN含量分别降低了4.19 mg/dL (P<0.01)、4.81 mg/dL (P<0.01),10%组BUN值与对照组无显著差异(P>0.05);日粮添加不同水平的蒸汽压片玉米影响奶牛乳尿素氮(MUN)的含量,其中添加蒸汽压片玉米组MUN含量分别比对照组降低1.70 mg/dL (P<0.05)、2.48 mg/dL (P<0.01)、2.92 mg/dL (P<0.01)。血清钙、磷的含量呈增加趋势,其中30%组血清钙水平显著高于对照组(P<0.05)。(7)蒸汽压片玉米替代普通碾碎玉米,显著的降低了奶牛氮的排放,有降低奶牛磷排放的趋势。试验组奶牛氮排放量分别比对照组降低了4.23% (P>0.05)、9.37% (P<0.05)和10.29% (P<0.05),磷排放量分别比对照组降低了1.93% (P>0.05)、2.59% (P>0.05)和5.19% (P>0.05)。(8)试验组奶牛的经济效益分别提高4.93元/头·日、6.31元/头·日和6.42元/头·日。
综合评定认为,本试验条件下,奶牛日粮中添加蒸汽压片玉米大幅度提高了奶牛生产性能和经济效益,有效的降低了氮、磷的排放,确定蒸汽压片玉米最佳添加范围为混合精料的10%~20%。
The experiment was conducted to study the effects of steam-flaked corn (SFC) on the performance, metabolic parameters, excretion of nitrogen and phosphorus and the optimal dose of Holstein cows during early lactatation period.
Eight primiparous healthly Holstein cows in early lactatation with similar milk yield and parturition date were selected in a replicated 4×4 Latin square design, and were assigned randomly into 4 groups each with 2 replicates. Steam-flaked corn contents in the experimental ration were dividedly 0%, 10%, 20% or 30% of the concentrate. There were four 28-d periods. The results indicated that dry matter intake (DMI) was unaffected by diet (P>0.05), but steam-flaked rather than dry- ground corn (DGC) in diets could significantly increase the feed efficiency (4%FCM/DMI) (P<0.05). The apparent digestibility of nutrients were unaffected by diet (P>0.05). The milk yields (SFC supplement at 10%, 20% or 30%, separately) were respectively higher 1.76 kg/d (P >0.05), 2.38 kg/d (P <0.05), 2.54 kg/d (P<0.05) than that of the control group, but no significant difference appeared among the treatment groups (P>0.05); FCM yield for cows fed concentrate diets containing 20% or 30% SFC was separately significantly increased 2.78 kg/d (P<0.01) or 2.87 kg/d (P<0.01) than the control diet. The percentages of milk fat, protein, lactose and non-fat solid (SNF) were unaffected by diet (P>0.05), but tended to increase except milk fat; The yield of milk fat, protein, lactose and non-fat solid were increased (P<0.05) for cows fed SFC diets. Milk fat and protein yield of the 30% group was significantly higher 0.11 kg/d (P<0.01) and 0.1 kg/d (P<0.01) than those of the control group (1.07 kg/d vs 0.86 kg/d). Steam-flaking corn tended to decrease SCC by 8.73% (P>0.05),11.92% (P>0.05),17.88% (P>0.05), respectively; SFC in diets could significantly increased serum glucose concentration (P<0.05) and decreased serum non-etherified fatty acid (NEFA) concentration (P<0.01). Compared to the control group, the serum glucose concentration were separately increased 3.92mg/dL (P>0.05), 6.25 mg/dL (P<0.05)and 6.96mg/dL (P<0.01),the NEFA concentration were separately decreased 23.92 mg/dL (P<0.01), 29.84 mg/dL (P<0.01), 38.93 mg/dL (P<0.01);SFC in diets could significantly decreased Blood urea nitrogen (BUN) and Milk urea nitrogen (MUN) concentration (P<0.01). Compared to the control group, the BUN concentration were separately decreased 1.11mg/dL (P>0.05), 4.19 mg/dL (P<0.01)and 4.81 mg/dL (P<0.01),the MUN concentration were separately decreased 1.70mg/dL (P<0.05), 2.48 mg/dL (P<0.01), 2.92 mg/dL (P<0.01);the serum calcium (Ca) and phosphorus (P) were tended to increased (P>0.05).Comparing with the control group (0%SFC), SFC diet had decreased the excretion of nitrogen and phosphorus, the excretion of nitrogen of the cows fed with the SFC diets were decreased by 4.23%(P>0.05),9.37%(P<0.05)and 10.29%(P<0.05),and the excretion of phosphorus were decreased by 1.93% (P>0.05),2.59% (P>0.05)and 5.19% (P>0.05).The income of feeding a cow with the diet Including SFC were separately increased 4.93 RMB/d, 6.31 RMB/d and 6.42 RMB/d ,comparing with the control group.
In summary, The SFC in diet could improve the performance and economic profit of feeding, decrease the excretion of nitrogen and phosphorus. As all of qualification were concerned, the optimal dost of SFC was 10% to 20 % in the concentrate of dairy cows in early lactation.
选择8头泌乳早期的经产中国荷斯坦奶牛,随机分为4组,每组2头,试验前各组奶牛日均产奶量、胎次、泌乳天数、体重差异不显著(P<0.05)且健康无疾病。采用4×4重复拉丁方设计。各组实验日粮精粗比一致,其中,A组为对照组(仅饲喂基础日粮),B组、C组和D组为试验组,其精饲料中蒸汽压片玉米含量分别为10%、20%和30%。试验分四期,每期28d。
结果表明:(1)日粮中添加蒸汽压片玉米对奶牛干物质采食量没有显著影响(P>0.05),但显著提高了饲料转化率(奶料比)(P<0.05);(2)日粮中蒸汽压片玉米的添加在不同程度上提高了日粮中养分的表观消化率,但均未达到显著水平(P>0.05);(3)试验组奶牛产奶量和4%FCM产量均显著提高,其中10%组、20%组和30%组奶牛的产奶量分别比对照组提高1.76 kg/d (P>0.05),2.38 kg/d (P<0.05)和2.54 kg/d (P<0.05),但各试验组之间差异不显著(P>0.05);20%组与30%组的4%FCM产量分别比对照组提高2.78 kg/d (P<0.01)和2.87 kg/d (P<0.01),达到了极显著水平;(4)蒸汽压片玉米的添加对乳指标率无显著影响(P>0.05),乳蛋白、乳糖、乳非脂固形物产量显著增加,其中30%组乳脂量和乳蛋白量分别比对照组(1.07 kg/d,0.86 kg/d)提高0.11 kg/d和0.1 kg/d,达到极显著水平(P<0.01);(5)试验组奶牛乳体细胞数分别比对照组降低了8.73%、11.92%和17.88%,但各组差异均不显著(P<0.05);(6)日粮中添加蒸汽压片玉米组奶牛的血糖含量较对照组都有提高,试验各组较对照组分别提高3.92 mg/dL (P>0.05)、6.25 mg/ dL (P<0.05)和6.96 mg/ dL(P<0.01);日粮中添加蒸汽压片玉米可降低奶牛血清游离脂肪酸的含量,试验各组较对照组分别降低23.92 mg/dL (P<0.01)、29.84 mg/dL (P<0.01)和38.93 mg/dL (P<0.01),其中30%组和10%组之间也存在显著性差异(P<0.05);日粮添加蒸汽压片玉米可降低奶牛血清尿素氮(BUN)的含量,其中20%、30%两组比对照组BUN含量分别降低了4.19 mg/dL (P<0.01)、4.81 mg/dL (P<0.01),10%组BUN值与对照组无显著差异(P>0.05);日粮添加不同水平的蒸汽压片玉米影响奶牛乳尿素氮(MUN)的含量,其中添加蒸汽压片玉米组MUN含量分别比对照组降低1.70 mg/dL (P<0.05)、2.48 mg/dL (P<0.01)、2.92 mg/dL (P<0.01)。血清钙、磷的含量呈增加趋势,其中30%组血清钙水平显著高于对照组(P<0.05)。(7)蒸汽压片玉米替代普通碾碎玉米,显著的降低了奶牛氮的排放,有降低奶牛磷排放的趋势。试验组奶牛氮排放量分别比对照组降低了4.23% (P>0.05)、9.37% (P<0.05)和10.29% (P<0.05),磷排放量分别比对照组降低了1.93% (P>0.05)、2.59% (P>0.05)和5.19% (P>0.05)。(8)试验组奶牛的经济效益分别提高4.93元/头·日、6.31元/头·日和6.42元/头·日。
综合评定认为,本试验条件下,奶牛日粮中添加蒸汽压片玉米大幅度提高了奶牛生产性能和经济效益,有效的降低了氮、磷的排放,确定蒸汽压片玉米最佳添加范围为混合精料的10%~20%。
The experiment was conducted to study the effects of steam-flaked corn (SFC) on the performance, metabolic parameters, excretion of nitrogen and phosphorus and the optimal dose of Holstein cows during early lactatation period.
Eight primiparous healthly Holstein cows in early lactatation with similar milk yield and parturition date were selected in a replicated 4×4 Latin square design, and were assigned randomly into 4 groups each with 2 replicates. Steam-flaked corn contents in the experimental ration were dividedly 0%, 10%, 20% or 30% of the concentrate. There were four 28-d periods. The results indicated that dry matter intake (DMI) was unaffected by diet (P>0.05), but steam-flaked rather than dry- ground corn (DGC) in diets could significantly increase the feed efficiency (4%FCM/DMI) (P<0.05). The apparent digestibility of nutrients were unaffected by diet (P>0.05). The milk yields (SFC supplement at 10%, 20% or 30%, separately) were respectively higher 1.76 kg/d (P >0.05), 2.38 kg/d (P <0.05), 2.54 kg/d (P<0.05) than that of the control group, but no significant difference appeared among the treatment groups (P>0.05); FCM yield for cows fed concentrate diets containing 20% or 30% SFC was separately significantly increased 2.78 kg/d (P<0.01) or 2.87 kg/d (P<0.01) than the control diet. The percentages of milk fat, protein, lactose and non-fat solid (SNF) were unaffected by diet (P>0.05), but tended to increase except milk fat; The yield of milk fat, protein, lactose and non-fat solid were increased (P<0.05) for cows fed SFC diets. Milk fat and protein yield of the 30% group was significantly higher 0.11 kg/d (P<0.01) and 0.1 kg/d (P<0.01) than those of the control group (1.07 kg/d vs 0.86 kg/d). Steam-flaking corn tended to decrease SCC by 8.73% (P>0.05),11.92% (P>0.05),17.88% (P>0.05), respectively; SFC in diets could significantly increased serum glucose concentration (P<0.05) and decreased serum non-etherified fatty acid (NEFA) concentration (P<0.01). Compared to the control group, the serum glucose concentration were separately increased 3.92mg/dL (P>0.05), 6.25 mg/dL (P<0.05)and 6.96mg/dL (P<0.01),the NEFA concentration were separately decreased 23.92 mg/dL (P<0.01), 29.84 mg/dL (P<0.01), 38.93 mg/dL (P<0.01);SFC in diets could significantly decreased Blood urea nitrogen (BUN) and Milk urea nitrogen (MUN) concentration (P<0.01). Compared to the control group, the BUN concentration were separately decreased 1.11mg/dL (P>0.05), 4.19 mg/dL (P<0.01)and 4.81 mg/dL (P<0.01),the MUN concentration were separately decreased 1.70mg/dL (P<0.05), 2.48 mg/dL (P<0.01), 2.92 mg/dL (P<0.01);the serum calcium (Ca) and phosphorus (P) were tended to increased (P>0.05).Comparing with the control group (0%SFC), SFC diet had decreased the excretion of nitrogen and phosphorus, the excretion of nitrogen of the cows fed with the SFC diets were decreased by 4.23%(P>0.05),9.37%(P<0.05)and 10.29%(P<0.05),and the excretion of phosphorus were decreased by 1.93% (P>0.05),2.59% (P>0.05)and 5.19% (P>0.05).The income of feeding a cow with the diet Including SFC were separately increased 4.93 RMB/d, 6.31 RMB/d and 6.42 RMB/d ,comparing with the control group.
In summary, The SFC in diet could improve the performance and economic profit of feeding, decrease the excretion of nitrogen and phosphorus. As all of qualification were concerned, the optimal dost of SFC was 10% to 20 % in the concentrate of dairy cows in early lactation.
引文
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