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41.
The present study explores the welfare aspects of involuntary milking in dairy herds with an automatic milking system (AMS) as it focuses on whether fetching of cows for milking may be related to fear/discomfort of the automatic milking unit (AMU) or the milking itself and further, may strain the human–animal relationship. Behavioural data on cow reluctance when entering the AMU, stepping and kicking behaviour during milking and avoidance of humans was collected at 6 two-day visits to 8 Danish commercial AMS herds during a year. The data set for the analysis included one observation per cow of reluctance when entering the AMU and behaviour during milking of a total of 869 cows; 255 cows fetched for milking and 614 non-fetched cows. For 82 of the cows fetched for milking and for 370 of the non-fetched cows the data further included one observation per cow of avoidance towards an approaching unfamiliar human in a test situation. Multivariate analyses by conditional hierarchical log-linear models showed that fetchings were more frequent the first 14 days of lactation (P < 0.001). The multivariate analysis showed no associations between fetching and reluctance at entering the AMU, nor an association to stepping and kicking during milking. However, compared to non-fetched cows, fetched cows were more frequently avoiding the test person in the human approach test (P < 0.001). It is concluded that fetching may strain the human–animal relationship.  相似文献   
42.
An on-farm experiment was performed to investigate the effects of two milking systems on teat condition. An auto-tandem milking parlor made by GEA® with a conventional milking cluster (CON) and a single tube milking system called MultiLactor® (MULTI) from Siliconform GmbH were tested. For both milking system, in total 73 animals were milked over a period of seven months. To assess the effect of milking on teat condition, each teat was scored according to teat-condition evaluation systems. To evaluate teat condition, the teat color, ring formation at the teat base and formation of teat hyperkeratosis were assessed. The evaluation was conducted once a month after milking. The collected data were then statistically analyzed with generalized linear mixed models. The only differences found between the two milking systems occurred with respect to their effect on teat color. MULTI showed significantly better scores compared to CON. There were no significant differences between the milking systems with regard to teat-end hyperkeratosis and ring formation at the teat base.  相似文献   
43.
韩勇  邓媛  沈枫  姜秀英  刘军  刘博 《安徽农业科学》2008,36(5):1852-1855,1925
对辽宁省4个冠层形态具有一定差异但又具有较高产量水平的杂交粳稻组合与常规水稻品种辽粳294在籽粒灌浆期的光合生理生态特性进行了比较研究。结果表明:杂交粳稻各组合单株产量明显高于常规对照品种,每穴穗数比对照有所降低,每穗颖花数比对照高出很多,结实率和千粒重差别不大;各杂交组合的上功能叶叶面积和群体LAI都高于对照品种,各组合的叶绿素含量和光合速率平均值在灌浆初期与对照品种差别不明显,在水稻灌浆末期,各杂交组合的茎鞘干物质输出率差别较大。  相似文献   
44.
Goats are important in the low-input systems of West Africa and their main importance lies in their role for income and saving. In addition, it is known that milk offtake for home consumption is also important. In order to obtain information about the real importance of milk offtake, a recording scheme was operated in 27 villages in the Central River Division of The Gambia from July 1998 until January 2000. Detailed information was obtained from about 1500 kiddings. In the recording scheme, any sheep being milked as well as the goats of the International Trypanotolerance Centre nucleus flock were also recorded. In the villages, 36% of all lactations were used for milk offtake, but the fraction milked was lower for the first two lactations. The average length of lactation was 127 days and the average daily milk offtake was 0.18 L. Goats are milked once a day and the residual milk is left for the kids. Milking starts about one week after parturition and stops when the goat becomes pregnant or the kid(s) die or the goat is drying off. The repeatability of the 90-day milk offtake was 0.24 ± 0.09. Sixty-five percent of goat owner were women and a large fraction of goat owners also owned cattle. Goat milk was used exclusively for home consumption. It is concluded that in breeding and extension work more attention should be given to aspects of milk production.  相似文献   
45.
主要研究放牧制度对谢尔塔拉地区天然草地土壤物理性状以及对三河牛泌乳性能的影响。试验结果表明,不同放牧制度对土壤含水量、容重和孔隙度具有显著影响(p<0.05),其中轮牧区土壤含水量和容重均高于连牧区。放牧制度对泌乳量影响显著,轮牧区的产奶量提高了近25%(p<0.05),但放牧制度对乳脂率和乳蛋白含量影响不大(p>0.05)。  相似文献   
46.
The effect of three wheat grain treatments on the zootechnical performance (feed intake, milk production and milk fat and protein production) of dairy cattle was studied with 18 Holstein cows in each of two feeding trials (both a 3 × 3 Latin square design). Rolled wheat, NaOH treated wheat and immature wheat ensiled with Graintona-Plus (Vee-lik, Zuienkerke, Belgium) were compared in a ration with fixed DM proportions of wheat, maize silage and prewilted grass silage. The nutritive value of the three wheat treatments was derived from in situ rumen degradability studies and from in vivo digestibility experiments.

In situ rumen incubations showed that NaOH treatment strongly decreased protein and starch degradability of the wheat. Due to that importantly decreased starch degradability NaOH treated wheat may be a source of starch with a reduced risk of rumen acidosis as compared to rolled wheat. On the other hand, due to the ensiling, immature wheat had a very high washable starch fraction, despite the Graintona-Plus treatment. The protein value differed importantly, with the DPI (true protein digested in the small intestine; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value being 103, 125 and 76 g/kg DM for rolled, NaOH treated and ensiled wheat, respectively. The RDPB (degraded protein balance; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value of the NaOH treated wheat was − 51 vs. − 37 and− 33 g/kg DM for rolled and ensiled wheat. In vivo digestibility trials with Holstein cows indicated that the net energy value of the wheat treatments was not significantly different.

In Trial 1, all diets were formulated to supply 105% of the requirements of DPI and net energy lactation (NEL; [Van Es, A.J.H., 1978. Feed evaluation for ruminants: I. The system in use from May 1977 onwards in the Netherlands. Livest. Prod. Sci. 5, 331–345]) and a safe RDPB level (± 200 g/day). On average 4.6 kg wheat DM was fed daily. Following trial 1, trial 2 was carried out, with the maize silage, grass silage and wheat fed in the same proportions as in trial 1, but fed ad libitum, to compare the intake level of the three diets. In both trials, the NaOH treated wheat resulted in the best performance with importantly increased milk yield and the highest yield of fat and protein corrected milk. Ensiled immature wheat resulted in a significant lower milk production and milk protein yield and in a higher milk fat content. In trial 1, DM-intake of the three groups was comparable due to the experimental design. In trial 2 intake of the cows fed NaOH treated wheat was significantly higher (23.5 vs. 21.1 kg/day for the other two groups).  相似文献   

47.
在用挤奶设备质量安全监测为奶牛生产性能测定结果分析、提高挤奶设备使用水平、指导牧场养殖生产和保障奶源质量安全提供了强有力的技术支撑。本文通过总结在用挤奶设备质量安全监测项目实施情况,汇总了分析监测数据,总结了监测经验,提出了监测结果运用及复制推广监测经验的建议。  相似文献   
48.
Automatic milking systems (AMS) allow recording of alternative milkability measures. Our objectives were to estimate genetic parameters for teat cup attachment failures (AtF), incomplete milkings (IM), and handling time (HT), and their genetic correlations with box time (BT), udder traits and temperament. Teat coordinates were to measure udder conformation and teat placement. Genetic correlations were estimated between these traits and linear classification traits. Data on Swedish Holstein and Swedish Red cows in 19 AMS herds and 74 herds with conventional milking parlors were analyzed. HT and IM had low heritabilities, but that of AtF was 0.21–0.31. Genetic correlations between AtF and temperament were 0.44–0.71 (calm cows having low AtF). Short BT was weakly genetically associated with shallow udders with short and thin teats. High genetic correlations (0.91–0.98) were found between teat coordinate traits and linear classification traits. Thus, AMS records can be effectively used to select for improved milkability and temperament.  相似文献   
49.
对192头成年荷斯坦牛乳中体细胞数及乳房性状与泌乳性能的相关性进行研究,结果表明:乳中体细胞数较高,9月份达到最高水平;乳房性状评分偏低。体细胞数与月产奶量、月乳脂产量及月乳蛋白产量等性状有极显著负相关(p<0.01),与乳脂率和乳蛋白含量无显著相关关系(p>0.05);后乳房宽度与月产奶量、月乳脂产量及乳蛋白产量有极显著正相关(p<0.01)。  相似文献   
50.
果洛家牦牛产乳性能测定   总被引:1,自引:0,他引:1  
对果洛州玛沁县雪山乡 10头经产、初产家牦母牛一个夏季的挤乳量进行了测定。测定结果 :经产母牛平均日挤乳量 1.0 6± 0 .16kg ,初产母牛为 0 .67± 0 .0 9kg ,经产母牛显著高于初产母牛 (P <0 .0 5 )。乳脂率含量经产母牛为6.5 7%± 0 .2 3 %,初产母牛为 6.69%± 0 .15 %,差异不显著 (P >0 .0 5 )  相似文献   
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