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1.
热应激对牛奶中生化指标的影响 总被引：1，自引：0，他引：1
对比研究热应激与非热应激期泌乳奶牛全乳中各种矿物元素含量的变化和乳清中的酶活性以及各种抗氧化指标的变化,发现夏季热应激使奶牛全乳中常量元素和微量元素代谢紊乱,酶活性发生变化。试验结果表明热应激使泌乳奶牛乳腺组织氧化代谢异常、自由基产生过多而导致乳腺细胞氧化损伤。 相似文献
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冷、热应激对奶牛血液生理生化指标影响 总被引：1，自引：0，他引：1
以16头荷斯坦牛为实验对象,研究不同环境温度下冷应激（-30℃、-20℃、-5℃）与热应激（31℃）对奶牛的血液生理常值、生化指标的影响。研究结果表明在冷应激期：（1）白细胞、红细胞、血小板和单核细胞的变化在温差15qC尤为突出（P〈0．05）;（2）血清中Ca2＋的含量随着温度的降低而降低（P〈0．05）;（3）血清P含量无明显变化（P〉0．05）,降至-30℃时血清P含量显著降低（P〈0．05）。在热应激期：白细胞、红细胞及单核细胞的变化尤为突出。（1）白细胞、红细胞数目均减少（P〈0．05）;（2）嗜碱性粒细胞、单核细胞有显著的变化（P〈0．05）。通过本次试验,在严寒和炎热环境下,采取各种有效措施缓解奶牛血液中各项指标的变化,以达到预防冷、热应激的目的,同时研究我区奶牛在冷、热刺激下的生理变化,为进一步制定缓解奶牛冷、热应激的技术措施提供理论依据。 相似文献
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为了探讨动物在不同环境温度时 ,乳样中某些生化指标变化的规律性 ,以健康荷斯坦奶牛为试验对象 ,研究不同环境温度下 (5℃、10℃、15℃、2 0℃、2 5℃ )对奶牛乳清的某些生化指标的影响。研究结果表明 ,环境温度为 2 0℃时 ,乳清天门冬氨酸氨基转移酶 (AST)活性最高 ,显著高于其它各组 ;乳清肌酸激酶 (CK)活性在 5℃和 2 5℃时极显著高于各中间温度组 ;丙氨酸氨基转移酶 (ALT)从 5℃至 2 0℃逐渐升高 ,且 2 0℃组显著高于 2 5℃组 ;乳清总蛋白 (TP)含量 5℃组为最低 ,而 10℃、15℃和 2 5℃组为高 ;乳清中尿素氮 (BUN)则随环境温度的升高呈逐渐降低的趋势 ,且 2 5℃组显著低于其它各温度组。上述实验结果可能说明外界环境温度的变化 ,可对泌乳奶牛乳清中的某些酶活性及代谢成分具有显著影响。 相似文献
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为了进一步验证S441分子标记对奶牛抗热应激的影响,挑选有、无S441标记的中国荷斯坦奶牛各9头分别作为试验A组和试验B组,对2组奶牛在不同热应激状态下的生理生化指标变化进行了测定和分析。结果表明：（1）在生理指标测定中,产奶量随热应激增强而降低,直肠温度随热应激增强而升高,白细胞总数（WBC）、淋巴细胞数（LYM）和单核细胞数（MXD）随热应激增强而下降,但A组变化辐度较B组低,并在一定的热应激期间达到显著性差异（P〈0.05）。（2）在生化指标测定中,随着热应激的增强,2组奶牛的Se、谷胱甘肽过氧化物酶（GSH-Px）、三碘甲腺原氨酸（T3）、四碘甲腺原氨酸（T4）和皮质醇（Cort）的总体均值呈逐渐下降趋势,促肾上腺皮质激素（ACTH）的总体均值呈逐渐升高趋势,但试验A组奶牛较试验B组变化幅度低;其中Se和GSH-Px总体均值在严重热应激期间达到显著性差异（P〈0.05）;试验A、B组奶牛的红细胞钾含量均不随热应激条件的变化,且试验A组的含量极显著低于试验B组。S441分子标记与抗热应激能力相关的各项生理生化指标均具有较强的相关性,可以作为一种奶牛抗热应激分子标记应用于品种选育和生产中。 相似文献
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热应激对泌乳奶牛血液生化指标的影响 总被引：14，自引：1，他引：14
对比研究热应激与非热应激期奶牛血液生化指标的变化，结果发现夏季慢性热应激使奶牛血清中甲状腺激素(T3与T4)、催乳素(PRL)和皮质醇(cort)水平均显著下降(P<0.05)。同时，热应激显著降低奶牛血清中钙(Ca)、钠(Na)、钾(K)水平(P<0.05)，但对血清镁(Mg)无显著影响(P>0.05)；血清中乳酸脱氢酶(LDH)活性显著降低(P<0.05)，而肌酸激酶(CK)活性极显著升高(P<0.01)。试验结果表明热应激使泌乳奶牛内分泌紊乱。 相似文献
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《养殖与饲料．饲料世界》2021,(7)
热应激会使奶牛产生一系列生理变化,如免疫力下降、生化指标发生变化等,从而使奶牛生产性能受到严重影响,因此,夏季高温热应激便成为困扰各奶牛养殖场发展的首要问题。为此,本文介绍了热应激对奶牛采食消化量、产奶性能、繁殖性能、内环境等的影响;提出了避免奶牛热应激的具体措施:严格控制奶牛生长环境,科学合理搭配日粮结构,加强奶牛日常饲养管理。 相似文献
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对比热应激期和非热应激期奶牛乳清中阴阳离子含量变化和电荷总量,发现热应激期牛奶胶体体系中阳离子不足而阴离子过剩,以致全乳PH值显著降低。同时,全乳中体细胞数显著升高表明热应激对奶牛乳腺组织有一定程度的损伤。 相似文献
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Hisaeda K Hagiwara K Eguchi J Yamanaka H Kirisawa R Iwai H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):1009-1011
Concentrations of interferon-gamma (lFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) were determined in serum and whey samples from cattle with naturally occurring coliform mastitis for two weeks after onset using bovine INF-gamma and TNF-alpha-specific ELISA. In serum and whey samples from healthy cows. IFN-gamma was almost undetectable and TNF-alpha was detected at low levels. At the onset of illness, INF-gamma in sera and whey and TNF-alpha in whey from the mastitic cows were significantly higher than their respective values in healthy cows. Concentrations of IFN-gamma and TNF-alpha in whey from mastitic cattle decreased significantly as the cows recovered. 相似文献
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E D Watson 《Research in veterinary science》1989,47(2):253-256
Milk samples were collected from 21 non-pregnant cows to study the ability of milk whey to support in vitro bactericidal activity of neutrophils against Actinomyces pyogenes. Significant differences (P less than 0.01) existed in opsonising ability of milk whey samples from individual cows. Antibody titres to A pyogenes in milk whey were determined using an enzyme linked immunosorbent assay. Bactericidal activity of neutrophils incubated with milk whey was positively correlated (P less than 0.05) with titres of IgG2 and IgM antibodies but not with IgG1 or IgA antibodies. 相似文献
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热应激对荷斯坦奶牛体温和呼吸的影响 总被引：1，自引：0，他引：1
本试验旨在研究热应激对不同泌乳阶段奶牛直肠温度、皮肤温度和呼吸频率的影响。选用不同泌乳阶段、胎次相近的荷斯坦奶牛18头,按泌乳天数分为泌乳前期、泌乳中期和泌乳后期3组,每组6个重复,根据牛舍温湿指数(THI)变化情况,进行热应激与非热应激的自身对照试验。结果表明:热应激极显著增加各泌乳阶段奶牛的直肠温度、皮肤温度和呼吸频率(P<0.01);THI与各泌乳阶段奶牛的直肠温度、皮肤温度、呼吸频率呈显著正相关(P<0.05);在同一环境下,不同泌乳阶段奶牛的直肠温度、皮肤温度及呼吸频率无显著差异(P>0.05)。热应激严重影响奶牛的直肠温度、皮肤温度和呼吸频率,与泌乳中、后期奶牛相比,热应激对泌乳前期奶牛的影响趋于较大。 相似文献
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Effects of feeding supplemental fat to beef cows on cold tolerance in newborn calves 总被引：2，自引：0，他引：2
Our objectives were to examine the effects of added fat in late-gestation cow diets on neonatal response to cold. In Exp. 1, pregnant fall-calving heifers received control (n = 5), safflower seed (n = 5), or whole cottonseed (n = 5) diets. The hay-based, isonitrogenous, and isocaloric diets, fed for 47 d prepartum, contained 1.5, 4.0, and 5.0% fat for control, safflower, and whole cottonseed diets, respectively. At calving, calf BW and vigor score, as well as fat, lactose, and IgG in colostrum were not affected (P > 0.30) by diet. Heifers fed the safflower diet tended to have greater colostral solids (P < 0.10) than heifers fed the control or whole cottonseed diets. At 6.5 h of age, calves were placed in a 5 degrees C cold room for 90 min. Calf vigor, shivering, body temperature, and blood samples were taken every 15 min. During cold stress, calf body temperature decreased 0.7 degrees C (P < 0.03). Across all diets, shivering and serum glucose concentrations increased (P < 0.05), whereas calf vigor and cortisol concentrations decreased (P < 0.02) during cold exposure. In Exp. 2, pregnant spring-calving cows (n = 98) received a control (n = 47) or whole cottonseed (n = 51) supplement. Hay-based diets fed for 68 d prepartum contained 2.0 and 5.0% fat for control and whole cottonseed diets, respectively. Calf BW, vigor, shivering, dystocia score, time to stand, time to nurse, serum glucose concentrations, and serum IgG were not affected (P > 0.50) by diet. Between 30 and 180 min, body temperature of calves from dams fed the whole cottonseed supplement decreased (P < 0.05) more than calves from dams fed the control supplement. Serum glucose concentrations in calves were not affected by diet (P > 0.30). Serum cortisol concentrations tended (P < 0.09) to be greater for calves from dams fed whole cottonseed than control calves. When ambient temperature was < 6 degrees C, calves born to dams fed whole cottonseed had greater (P < 0.05) BW, tended (P < 0.1) to stand earlier, and had greater serum IgG concentrations. We conclude that calves from dams fed high-fat diets containing safflower or whole cottonseed respond similarly to cold stress, but these responses may not be consistent with greater cold resistance. In addition, high-fat dietary supplementation of late-gestation cows may only be beneficial during calving seasons with prolonged cold weather. 相似文献
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试验为研究日粮中添加菌糠对荷斯坦奶牛产奶量、乳品质、血液生化指标及抗氧化功能的影响,根据单因素随机设计,将健康、体重接近的90头荷斯坦奶牛随机分为3个处理组,每组30头。对照组奶牛饲喂基础日粮;试验1组饲喂5%的菌糠;试验2组饲喂10%的菌糠。预试期7 d,正式试验期30 d。结果表明:与对照组相比,菌糠组的乳品质指标总固形物和奶中体细胞数显著降低(P<0.05)。菌糠组奶牛血液中胆固醇含量显著升高(P<0.05),尿素氮含量显著降低(P<0.05)。日粮中添加10%的菌糠可以显著提高超氧化物歧化酶活性(P<0.05),显著降低丙二醛含量(P<0.05)。研究表明,在奶牛日粮中添加不超过10%的菌糠不会对产奶量、干物质采食及血液生化指标产生不利影响,并且能改善乳品质,提高奶牛机体抗氧化能力。 相似文献
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K L Anderson A R Smith R D Shanks H L Whitmore L E Davis B K Gustafsson 《American journal of veterinary research》1986,47(11):2405-2410
Milk whey immunoglobulins (Ig) and phagocytosis of staphylococci by milk polymorphonuclear neutrophilic leukocytes (PMN) were measured in 12 cows (allotted to 6 pairs) during acute bovine mastitis induced by intramammary inoculation of endotoxin. Six of these cows (or 1 in each pair) were treated with flunixin meglumine and were compared with the others (given only saline solution). The endotoxin inoculation comprised 10 micrograms of Escherichia coli O26:B6 lipopolysaccharide injected into one of the rear quarters (mammae). Flunixin meglumine was administered parenterally at a dosage of 1.1 mg/kg every 8 hours (total of 7 doses) beginning at 2 hours after endotoxin was injected. Milk samples were obtained, and whey samples were prepared from each quarter of each cow 3 times before inoculation and at 2, 4, 8, 12, 24, 48, 72, 96, 120, 144, 168, and 336 hours after endotoxin was inoculated. Significant increases (P less than 0.05) in milk whey IgG1, IgG2, IgM, and IgA concentrations were observed in whey samples from endotoxin-inoculated quarters. Greatest relative increase was seen for IgG2. Increased whey Ig concentrations were not observed in quarters which were not inoculated with endotoxin. Concentrations of whey IgG1 and IgM in endotoxin-inoculated quarters were significantly (P less than 0.05) decreased in flunixin meglumine-treated cows, compared with those in saline solution-treated cows. Significant increases in phagocytosis of staphylococci by milk PMN were observed in whey samples from endotoxin-inoculated quarters. Significant differences in PMN phagocytosis were not found in whey samples from cows given flunixin meglumine when compared with whey samples from cows given saline solution. 相似文献
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Hagiwara K Yamanaka H Hisaeda K Taharaguchi S Kirisawa R Iwai H 《Veterinary research communications》2001,25(2):99-108
Inflammatory cytokines, such as interleukin (IL)-6, have been shown to reflect clinical signs in certain conditions in diseased animals. In this study, we quantified the IL-6 concentrations in the serum and milk whey from 94 dairy cows with acute clinical mastitis and 55 healthy lactating cows. The IL-6 concentrations in serum from mastitic cows were significantly higher on the first day of illness compared to those of normal cows. Higher concentrations of IL-6 were also detected in the whey from mastitic cows, whereas low concentrations of IL-6 were detected in both serum and whey samples from normal cows. IL-6 concentrations in the serum taken at the onset of illness from cows that later required euthanasia were significantly higher than those in samples from cows that later recovered. These results suggest that serum IL-6 concentrations may be of prognostic value in identifying cows with severe mastitis. 相似文献
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[目的]为探讨中草药发酵制剂缓解奶牛热应激的调控作用和缓解奶牛热应激的营养调控措施。[方法]选用胎次相近、健康无病,体况均匀的40 头,随机分成4 组,分别设置为对照组、试验Ⅰ组、试验Ⅱ组、试验Ⅲ组,每组5 个重复,每个重复2 头。对照组奶牛饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组分别在饲喂基础日粮的基础上添加1%、2%和3%的中草药发酵制剂。[结果]通过检测生理指标、泌乳性能和血清生化指标结果表明,添加中草药发酵制剂后热应激奶牛的直肠温度和呼吸频次显著降低,平均日增重、平均日采食量显著提高,料重比显著降低（P<0.05）;奶牛的产奶量、乳脂率和乳蛋白率显著升高,体细胞数显著降低（P<0.05）;奶牛的白蛋白、总蛋白、尿素氮、血糖、谷丙转氨酶和谷草转氨酶含量均显著升高（P<0.05）。[结论]中草药发酵制剂可以有效缓解奶牛热应激,恢复正常的生理指标和血清生化指标水平,提高奶牛泌乳性能。在本试验条件下,日粮中中草药发酵制剂的适宜添加量为3%。 相似文献