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试验研究了不同泌乳阶段荷斯坦牛干物质采食量和钙、磷表观消化率的变化趋势。结果表明:泌乳9月、5月奶牛干物质采食量显著高于泌乳1月奶牛(P<0.05);泌乳1月、2月奶牛产奶量显著高于泌乳5月、9月奶牛;泌乳期内不同泌乳阶段对奶牛Ca、P表观消化率影响显著(P<0.05),泌乳1月和2月奶牛Ca、P表观消化率显著高于泌乳5月和9月(P<0.05)。 相似文献
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[目的]为了研究不同产犊季节对荷斯坦奶牛第一胎泌乳性能的影响,以便为长江中下游地区荷斯坦奶牛合理安排配种时间提供科学依据。[方法]利用海丰奶牛场有限公司2009年引进2480头澳系进口荷斯坦牛产犊季节及其第一胎泌乳性能的数据,分析不同产犊季节对第一胎泌乳天数、全泌乳期实际产奶量、305d校正奶量、305d脂肪产量和305d蛋白产量的影响。[结果]表明:不同产犊季节对第一胎泌乳天数和全泌乳期产奶量影响极显著(P0.01),显著影响305天脂肪产量(0.01P0.05),春季产犊的奶牛泌乳天数最长(358±10d),而冬季产犊的奶牛泌乳天数最短(299±18d),春季与夏季产犊奶牛的全泌乳期产奶量显著高于秋季、冬季产犊奶牛(P0.05),夏季产犊奶牛305d脂肪产量最高。[结论]综合各产犊季节样本量及相应泌乳性能,认为该场澳系进口荷斯坦牛最适宜产犊季节为夏末秋初,此时泌乳性能最好。该结果对同类地区引进澳系进口荷斯坦牛繁殖与生产管理有借鉴作用。 相似文献
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<正>1泌乳盛期奶牛的饲养管理泌乳盛期是指奶牛产后16～100d,在该阶段奶牛产奶量逐渐上升,中低产牛约在产后30～40d、高产牛在产后40～50d达到产奶高峰,维持一段时间后产奶量下降。此期产奶量约占全期总奶量的50%。泌 相似文献
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本研究收集宁夏地区1997—2018年63个奶牛场16.9万头荷斯坦牛的生产性能测定数据，从个体和群体水平拟合泌乳曲线，旨在探析我国高产奶牛群的泌乳性能特征及其影响因素。使用WOOD不完全伽马模型对奶牛的个体泌乳曲线进行拟合，并获得模型参数a、b、c以及二级参数泌乳持续力、高峰奶量、高峰日和305 d产奶量，进而采用线性模型分析胎次、产犊季节、初产月龄、出生年份和牧场规模等因素对泌乳曲线参数的影响。结果表明，高峰奶量为42.18±8.66 kg（平均值±标准差，下同），高峰日为86.15±42.88 d,305 d产奶量为10 023.98±2 139.89 kg。胎次、产犊季节、初产月龄、出生年份和牧场规模对宁夏奶牛泌乳曲线参数均有极显著影响。头胎牛产奶量极显著低于经产牛，夏季产犊奶牛的产奶量显著低于其他季节，初产月龄为22～24月龄时产奶量最高，牧场规模低于500头与高于500头奶牛产奶量存在极显著差异，高峰奶量与305 d产奶量随出生年份的增加而增加。这些研究结果为规模化牧场精细化管理和群体遗传改良提供了有用信息。 相似文献
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产犊季节和胎次对测定奶牛日泌乳性能的影响 总被引：1，自引：0，他引：1
[目的]通过研究产犊季节、胎次对奶牛测定日泌乳性能的影响,以期为指导日粮配方调整、增加牛奶产量和提升原料奶质量提供科学依据。[方法]采集江苏某奶牛场2012年度408头奶牛共3012条生产性能测定记录,用线性模型分析产犊季节和胎次对测定日产奶量、乳脂率、乳蛋白率、脂蛋比、305d产奶量及体细胞评分的影响进行分析。[结果]表明：不同产犊季节对测定日产奶量和305d产奶量的影响极显著（P〈0．01）,对乳脂率、乳蛋白率、脂蛋比无显著影响;不同胎次除对乳脂率影响显著外（P〈0．05）,对其它奶牛泌乳性能及体细胞评分均影响极显著（P〈0．01）。[结论]夏、秋两季产犊奶牛的305d产奶量高;2～3胎产犊奶牛的泌乳性能较佳,随着胎次的增加,特别是5胎及以后,泌乳性能的各项指标都有不同程度的降低。 相似文献
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通过对蜀宣花牛6 767个胎次的产奶量测定和1 055头母牛乳样的乳成分分析,揭示了蜀宣花牛的泌乳性能。牛群实际胎产奶量一世代平均3109.4kg,平均泌乳期281.4d,平均乳脂含量4.6%;二世代的平均产奶量、泌乳期和乳脂含量分别为3 311.3 kg、281.2 d和4.5%;三世代分别为3889.4 kg、283.5 d和4.5%;四世代分别为4 495.4 kg、297.0 d和4.2%。从不同胎次看,蜀宣花牛母牛的产奶量和泌乳天数均随胎次的递增而增加,第3~4胎达到高峰,从第5胎开始,随着母牛产犊胎次的递增,产奶量有所下降。蜀宣花牛乳脂含量明显高于黑白花奶牛、纯种西门塔尔牛和我国育成的草原红牛及新疆褐牛。表明蜀宣花牛具有较好的泌乳性能。 相似文献
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植物甾醇对泌乳前期奶牛产奶量及乳成分的影响 总被引：1，自引：0，他引：1
根据年龄、胎次、泌乳时间和产奶量选择24头泌乳奶牛,随机分为对照组、试验Ⅰ组和试验Ⅱ组。对照组饲喂奶牛场配制的全混合饲料,试验Ⅰ和Ⅱ组每头奶牛日粮中分别添加40 g/d和80 g/d植物甾醇,研究植物甾醇对奶牛生产性能的影响。结果表明,与对照组相比,试验Ⅰ和Ⅱ组奶牛的产奶量分别提高了2.07 kg/d(5.64%,P0.05)和1.74 kg/d(4.75%,P0.05);试验Ⅰ和Ⅱ组奶牛乳脂率分别提高了8.22%(P0.01)和2.97%(P0.05);乳蛋白率分别提高了2.45%(P0.05)和1.05%(P0.05);非脂固形物分别提高了1.29%(P0.05)和0.23%(P0.05),体细胞数分别下降了37.31%和19.34%,但差异均不显著(P0.05);牛奶中乳尿素氮含量分别降低了5.29%(P0.05)和7.58%(P0.01)。结果表明泌乳前期奶牛补饲一定量的植物甾醇能够提高产奶量和改善乳成分。 相似文献
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产奶量差是奶牛个体同一胎次前后2个泌乳月产奶量的差值,可准确反映产奶量变化情况。为探究影响荷斯坦牛产奶量差的因素,本研究收集整理了江苏省某大型奶牛场2015-2018年55 193头次荷斯坦牛生产性能测定记录,并利用最小二乘法分析胎次、测定年度、产犊季节、泌乳月4个因素对荷斯坦牛产奶量差的影响。结果显示:胎次、测定年度、产犊季节、泌乳月及其交互作用对产奶量和产奶量差均有极显著影响(P<0.01)。其中,不同胎次、测定年度和产犊季节的荷斯坦牛总产奶量在第2个泌乳月增加最快,产奶量差为8.79kg;头胎第6泌乳月、二胎第7泌乳月和三胎及以上第6泌乳月产奶量下降最大,产奶量差分别为-2.86kg、-4.59kg和-6.13kg;2015-2018年4个测定年度中,第10、第6、第7、第6泌乳月产奶量降低最大,产奶量差分别为-2.26kg、-4.98kg、-4.44kg和-3.56kg;春季产犊的荷斯坦牛第4泌乳月、夏季产犊的荷斯坦牛第12泌乳月、秋季产犊的荷斯坦牛第9泌乳月、冬季产犊的荷斯坦牛第6或第7泌乳月产奶量下降最大,产奶量差分别是-4.34kg、-4.71kg、-5.36kg和-5.40kg。此外,产奶量差与泌乳持续力呈极显著正相关(P<0.01),与产犊间隔呈显著正相关(P<0.05),与泌乳天数、高峰奶、乳脂率、蛋白率、305d产奶量呈极显著负相关(P<0.01)。因此,产奶量差作为衡量奶牛产奶量变化的指标之一,可为牧场进行科学饲养管理提供参考。 相似文献
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The effects of supplemental carbohydrate (CHO) sources on milk yield and composition,nitrogen (N) balance,and ruminal fermentation were evaluated in lactating dairy cows fed energy-deficient total mixed rations (TMR).Fifty-six lactating Holstein cows (36.8 ±3.4 kg/d of milk yield; 152 ±26days in milk [ DIM ] ) were randomly assigned to one of four diets:( 1 ) basal TMR ( control ) ; ( 2 ) basal TMR + 1.25 kg/d sucrose (SUC) ; ( 3 ) basal TMR + 2.12 kg/d steam-flaked corn ( SFC ) ; ( 4 ) basal TMR + 2.23 kg/d wheat (WHE).The trial lasted 70 days,including the first 10 days of adaptation.Simultaneously,a 4 × 4 Latin square trial was conducted with four ruminally cannulated cows of similar DMI (Dry Matter Intake) fed on the above four diets.Each testing period lasted 18 days:15 days for adaptation and 3 days for sampling.Cows fed SUC-,SFC-,and WHE-supplemented diets produced 1.6,2.9,and 0.8 kg/d,respectively,more milk than those on the basal TMR control diet,but the difference was not significant (P =0.160).However,the production of energy-corrected milk of cows fed CHO-supplemented diets improved significantly (P =0.020),and the yield of 4％ fat-corrected milk tended to be higher (P =0.063 ) than in control animals.Percentages of milk protein,lactose and solidsnot-fat (SNF) increased significantly in cows fed CHO-supplemented diets ( P ＜ 0.05 ),and yields of milk protein and SNF were significantly higher (P＜0.05); yields of milk fat and lactose were somewhat higher ( P ＜ 0.10 ).Cows receiving supplementary CHO diets consumed more DM (Dry Matter) ( P =0.023 ) ; however,there was no significant difference in N retention,digestibility,or utilization efficiency among the treatments (P ＞ 0.10 ).The average ruminal pH was lowest in cows supplemented with SUC,while that in cows supplemented with SFC and WHE was only slightly reduced (P =0.025 ).Ruminal NH3-N concentration was highest with no supplementary CHO ( P =0.017 ),and changes in postfeeding time were similar across the diets.Total volatile fatty acid concentration was significantly lower in control animals than in those on SUC- and WHE-supplemented diets ( P =0.001 ) ; significant dietary responses were observed in the concentrations of acetate,butyrate,and branched-chain fatty acids and in the acetate-to-propionate ratio ( P ＜ 0.001 ).These results indicate that supplementation with different CHO sources in energy-deficient diets substantially improved the balance of energy and N in the rumen,altered ruminal fermentation,and improved lactation performance in dairy cows. 相似文献
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AIMS: To compare the effect of two partial mixed ration diets containing either sulfate or chloride-based anionic salts, fed to grazing prepartum dairy cows, on concentrations of Ca, Mg, P and beta-hydroxybutyrate (BHB) in plasma, disease incidence and milk yield during the early postpartum period.
METHODS: The study was conducted on a seasonal-calving grazing dairy farm located in Benton (MO, USA). In August 2016, two groups of 200 cows were randomly assigned at 30 days before expected parturition to receive either a sulfate or chloride-based anionic diet, to achieve a dietary cation–anion difference (DCAD) of ?25?mEq/kg DM. Cows were fed partial mixed rations to provide 50% of their DM intake, with 50% provided by grazing fescue pasture. Urine samples were collected from 20 cows from each group once a week for 5 weeks until calving for pH assessment. At parturition, 42 cows per group were selected at random and blood samples collected on Days 1, 2, 3 and 7 postpartum. The study continued until 100 cows per group calved. Health events and cumulative milk yield until 30 days postpartum were recorded. Concentrations of Ca, P, and Mg in plasma at Days 1, 2, 3, and 7, and BHB in plasma at Day 7 postpartum were assessed.
RESULTS: Mean urine pH was lower in cows in the chloride than sulfate group (p≤0.06) on four of five sampling occasions. Mean concentrations of Ca in plasma on Day 1 were 2.00 (95% CI=1.94–2.05) and 1.91 (95% CI=1.88–1.97) mmol/L for the chloride and sulfate groups, respectively (p=0.15), and on Day 3 were 2.03 (95% CI=1.97–2.08) and 1.90 (95% CI=1.84–1.96) mmol/L, respectively (p=0.038). Concentrations of Mg, P and BHB in plasma and incidence of diseases postpartum were similar in both groups (p>0.05). There were no cases of clinical hypocalcaemia in either group.
CONCLUSIONS AND CLINICAL RELEVANCE: Prepartum cows fed a partial mixed ration with a negative DCAD containing chloride-based anionic salts and free access to a fescue pasture had lower prepartum urine pH, and higher concentrations of total Ca in plasma during the first week postpartum, than cows receiving a partial mixed ration containing sulfate-based anionic salts. 相似文献
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试验旨在比较高产和中产奶牛牛舍的空气状况。试验选取高产奶牛和中产奶牛牛舍各一栋,密闭采集测定甲烷（CH_4）、氨气、硫化氢和二氧化碳4种气体的浓度。结果表明：高产奶牛牛舍中甲烷、氨气、硫化氢和二氧化碳4种气体的浓度比中产奶牛牛舍中的各气体浓度分别提高2.69%、32.51%、3.58%和66.95%。每头高产奶牛每天排放CH_4 296.15g,每产1kg标准乳排放CH_4 11.61g。每头中产奶牛每天排放CH_4 210.54g,每产1kg标准乳排放CH_4 12.08g。随着采食量增加,牛舍中甲烷、氨气、硫化氢和二氧化碳的浓度也会增加。高产奶牛每产1kg标准乳的CH_4排放量比中产奶牛低3.89%。 相似文献
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《中国畜牧杂志》2019,(11)
为研究不同中性洗涤纤维/非纤维性碳水化合物(NDF/NFC)饲粮对泌乳后期奶牛甲烷排放量、营养物质消化率和生产性能的影响,试验选用体重(777.46±27.31)kg、胎次(1.5±0.15)胎、泌乳天数(242.92±15.28)d、产奶量(18.75±0.62)kg/d的奶牛12头,随机分配到3组,每组4头。各组饲粮NDF/NFC分别为2.10(精粗比为42:58)、1.96(精粗比为37:63)、1.52(精粗比为30:70),采用六氟化硫(SF_6)示踪技术测定自然状态下泌乳奶牛甲烷排放量。预试期14 d,正试期9 d。结果表明:饲喂不同NDF/NFC饲粮的泌乳后期奶牛甲烷排放量、甲烷能、单位干物质采食量的甲烷排放量以及单位总能摄入量的甲烷能均有显著差异;随着NDF/NFC降低,奶牛生产性能、饲料转化率和营养物质消化率无显著差异。综上,在不影响奶牛健康和生产性能的前提下,NDF/NFC为1.52的低NDF组饲料能显著降低泌乳后期奶牛瘤胃甲烷排放量。 相似文献
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日粮中添加不同水平氧化镁对奶牛泌乳性能血清镁含量及尿液pH值的影响 《畜牧与饲料科学》2022,43(5):74-78
[目的] 探究日粮中添加不同水平氧化镁对奶牛泌乳性能、血清镁含量及尿液pH值的影响。[方法] 选择胎次、泌乳量、泌乳天数相近的经产荷斯坦奶牛50头,随机分为5组,每组10头。Ⅰ组（对照组）饲喂基础日粮,Ⅱ组、Ⅲ组、Ⅳ组和Ⅴ组基础日粮中分别添加0.125%、0.250%、0.375%和0.500%的氧化镁（含量为70%）。预饲期7 d,正饲期70 d。记录采食情况和产奶量,计算干物质采食量;于试验第35天和第70天分别采集乳样、血样、尿样,测定乳蛋白含量、乳脂率、血清镁含量、尿液pH值。[结果] 在试验第35天和第70天,Ⅲ组的干物质采食量和产奶量显著（P<0.05）高于对照组;4个氧化镁添加组的乳蛋白含量均显著（P<0.05）高于对照组,Ⅲ组和Ⅳ组的乳脂率显著（P<0.05）高于对照组;4个氧化镁添加组的血清镁含量与对照组相比均无显著（P>0.05）差异;4个氧化镁添加组的尿液pH值均显著（P<0.05）高于对照组。[结论] 在奶牛日粮中添加氧化镁（含量为70%）能增加产奶量,提高乳脂率和乳蛋白含量;在该试验条件下,合理添加量为0.250%。 相似文献
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丙二醇对围产期奶牛能量平衡及代谢产物的影响 总被引：1，自引：0，他引：1
为了研究丙二醇对围产期奶牛能量平衡、血液指标和肝脏甘油三酯与糖原含量的影响。选用24头体质量(683.1±14.9)kg、胎次(2.5±0.2)、上一泌乳期305d产奶量(7 339±18)kg和预产期(24.5±0.2)d的经产奶牛,随机分为4组,从分娩前19d开始分别在基础日粮中添加丙二醇0、150、300和450mL.d-1。结果表明:与对照组相比,添加丙二醇300和450mL.d-1,显著提高了奶牛分娩后7、21和35d体况评分,缓减了奶牛体质量下降程度,改善了奶牛分娩前14d和分娩后7、21和35d奶牛能量平衡(P<0.05)。300和450mL.d-1组奶牛分娩前14d和分娩后7、21和35d血糖和胰岛素浓度显著高于对照组(P<0.05)。300和450mL.d-1组奶牛分娩后7、21和35d血浆游离脂肪酸、β-羟丁酸和甘油三酯浓度显著低于对照组(P<0.05)。300和450mL.d-1组奶牛分娩后7、21和35d肝脏甘油三酯含量显著低于对照组(P<0.05),但分娩后7、21和35d肝脏糖原含量显著高于对照组(P<0.05)。结果提示在日粮中添加丙二醇能够减少肝脏脂肪沉积,加强葡萄糖异生作用,改善奶牛能量平衡,适宜添加量为300mL.d-1。 相似文献
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Tiago Orlandi Claudio A. Pozo Jordana Schiavo Lisandre Oliveira Gilberto V. Kozloski 《Animal Science Journal》2020,91(1)
This study was carried out to evaluate the impact of including Acacia mearnsii tannin extract (TA) as a feed additive on nutrition and productive performance of dairy cows grazing a high‐quality temperate pasture and receiving supplementation with a concentrate feedstuff. Fourteen multiparous Holstein cows were assigned to either of the following treatments: concentrate without or with 20 g TA/kg dry matter (DM). Concentrate intake accounted for 32% of the total DM intake. Tannin addition increased the herbage DM intake by 22% (p < .05). There was no effect of TA inclusion on milk yield, milk composition, milk nitrogen (N) excretion, milk and plasma urea‐N concentration, urinary excretion of total N, urea‐N, and purine derivatives. However, TA inclusion increased the N intake and retention, total N excretion in manure, fecal N to urine N ratio, and decreased the dietary N efficiency for milk production and the percentage of ingested N excreted in urine (p < .05). In conclusion, supplementing dairy cows grazing a high‐quality temperate pasture with a concentrate containing 20 g TA/kg DM showed the potential of decreasing the proportion of ingested N excreted in urine without affecting the productive performance. 相似文献
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Effects of feeding and animal performance on nitrogen, phosphorus and potassium excretion by Holstein cows 总被引：1，自引：0，他引：1
Hideki KOJIMA Shin-ichi KUME Kazuhisa NONAKA Tomoko OSHITA Takaharu KOZAKAI Hiroyuki HIROOKA 《Animal Science Journal》2005,76(2):139-145
Thirty‐four Holstein dry cows and 16 lactating cows were used in balance trials to identify the effects of feeding and animal performance on nitrogen (N), phosphorus (P) and potassium (K) excretion by dairy cows, and to develop prediction models for these excreta. Orchard grass silage, corn silage, alfalfa silage or timothy hay were offered to dry cows. Orchard grass silage or alfalfa silage, and concentrates were offered to lactating cows. In the statistical analysis, the independent variables were bodyweight (kg), dry matter (DM) intake (kg/day), milk yield (for lactating cows only, kg/day), water intake (free water plus water in feed, kg/day), intake (g/day) of N, P and K and dietary contents (% of DM) of crude protein, P and K. The dependent variables were N, P and K excretion (g/day) in feces and urine. In both dry and lactating cows, intake of N, P and K had large effects on corresponding excretion. The results indicated that a decrease in the intake of N, P and K could decrease the corresponding excretion. Further research by path analysis showed that K intake positively affected urinary N excretion in dry cows indirectly, through water intake and urine volume. 相似文献
20.
饲喂高淀粉饲粮时不同瘤胃降解淀粉水平对奶牛泌乳性能、营养物质表观消化率和氮平衡的影响 总被引：1，自引：0，他引：1
本试验旨在研究饲喂高淀粉饲粮时不同瘤胃降解淀粉水平对奶牛泌乳性能、营养物质表观消化率和氮平衡的影响。选用10头荷斯坦经产奶牛[平均泌乳天数为(214±38)d,平均乳产量为(26.2±2.4)kg/d,平均体重为(727±65)kg]作为试验动物,随机分成2组,每组5头。试验设计2种不同瘤胃降解淀粉水平的试验饲粮,分别为瘤胃降解淀粉水平为62.3%(占总淀粉的百分比)的低瘤胃降解淀粉水平饲粮(L-RDS)和瘤胃降解淀粉水平为72.1%(占总淀粉的百分比)的高瘤胃降解淀粉水平饲粮(H-RDS)。采用交叉试验设计,试验分为2期,过渡期7 d,每期试验21 d,其中适应期14 d,采样期7 d。结果显示:1)相比L-RDS组,H-RDS组有机物和淀粉的表观消化率显著升高(P0.05),中性洗涤纤维和酸性洗涤纤维的表观消化率显著降低(P0.05),干物质表观消化率有升高趋势(P=0.07),蛋白质表观消化率无显著差异(P0.05)。2)相比L-RDS组,H-RDS组尿素氮及它们占摄入氮比例有降低趋势(P=0.09),摄入氮、乳氮、粪氮、尿氮和沉积氮及它们占摄入氮比例无显著变化(P0.05),尿中总嘌呤衍生物排出量和微生物蛋白产量亦无显著变化(P0.05)。3)饲粮瘤胃降解淀粉水平对奶牛干物质采食量、乳产量和乳成分均无显著影响(P0.05)。综合以上结果可知,饲喂高淀粉饲粮时不同瘤胃降解淀粉水平影响饲粮营养物质的表观消化率,对泌乳性能和氮平衡无显著影响。 相似文献