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牛羊复合营养舔块饲料适宜配方筛选的研究 总被引:10,自引:0,他引:10
通过原料配方试验和牛羊舔食量试验,研究了舔块原料配比、粘合剂种类、调质方法等对压制法生产舔块质量的影响,以及舔块硬度与牛羊舔食量的关系。研究证明,膨润土和生石灰是制备舔块饲料的良好粘合剂和固化剂,糖蜜对于提高舔块的硬度具有明显效果。某些通气性好的饼粕类有助于改善舔块压制过程的排气状况,提高舔块压制的质量。蒸汽直接对物料加热调质不利于提高舔块压制的质量。矿物盐舔块硬度对牛羊舔食量没有明显影响,但高蛋白舔块硬度影响舔食量。硬度越软,舔食量越大。 相似文献
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牛羊复合营养舔块饲料适宜配方筛选的研究 总被引:1,自引:0,他引:1
通过原料配方试验和牛羊舔食量试验,研究了舔块原料配比、粘合荆种类、调质方法等对压制法生产舔块质量的影响,以及舔块硬度与牛羊舔食量的关系。研究证明,膨润土和生石灰是制备舔块饲料的良好粘合剂和固化剂,糖蜜对于提高舔块的硬度具有明显的效果。某些通气性好的饼粕类有助于改善舔块压制过程的排气状况,提高舔块压制的质量。蒸气直接对物料加热调质不利于提高舔块压制的质量。矿物盐舔块硬度对牛羊舔食量没有明显影响,但高蛋白舔块硬度影响舔食量。硬度越软,舔食量越大。 相似文献
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沉水植物压块试验研究 总被引:1,自引:0,他引:1
对草型湖泊富营养化进行适度控制的关键技术是利用机械化方式收割沉水植物,同时结合自然资源的开发利用,走生态经济之路。沉水植物是一种富含蛋白质、矿物质及维生素的良好新型饲料资源,属于免费的高产青绿饲料,具有广阔的开发前景。本文以沉水植物为压缩物料进行了压块试验,研究了不同的含水率、模辊间隙对草块成形效果、密度、生产率的影响,确定了草块成形时物料含水率范围,模辊间隙范围,初步摸清了适于沉水植物压块的最佳物料含水率和模辊间隙,为提高草块成形质量、生产率提供依据。 相似文献
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《北方牧业(奶牛)》2009,(8):37-38
1秸秆的加工 饲草草块的加工技术一直受到世界的关注,它将饲草压缩成块,便于储存和运输。这方面国外发展较快,但是国外机械成本高,不可能靠进口设备解决我国的秸秆和饲草问题。历经数年努力,已有研制成功适合中国国情的秸秆饲草块加工设备,将玉米秸秆或其他牧草秸秆打碎后冷压成草块,体积缩小不到原来的15%,便于运输、长期储存和商品化。这为圈养牛羊发展畜牧业创造了条件。 相似文献
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1早春牧过早放牧会破坏草的营养,从而导致羊生长发育受阻,降低草的生长能力和产草量,加快草原的退化。2自由放牧不能充分发挥草的高效益并且造成浪费;每天到同块草场放牧,增加了寄生虫的感染机会;践踏草 相似文献
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山东省荣成市华兴机械有限责任公司研制开发出一种新型草块割碎机,该机解决牧草压块无机械破碎加工这一难题。牧草块是无续加压而成的粗饲料,在饲喂中只能通同时还对地瓜秧、花生秧等藤蔓进行切割破碎。是食草动物养殖场的好帮手。过人工撕破,费时费力,利用率低。草块割碎机通过输送切割破碎、抛送等工艺一次性完成,可按要求长短进行破碎加工,配套动力3千瓦,36×46草捆每分钟破碎30厘米长,CKGS—500草块割碎机$山东省荣成市华兴机械有限责任公司 相似文献
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青南牧区营养舔砖补饲藏羊效果的研究 总被引:1,自引:0,他引:1
在冬春枯草期 ,补饲营养舔砖对维护藏羊活重有明显作用。试验期 2个月 ,补饲营养舔砖试验组藏羊活重损失为 2 .0kg,而对照组为 5 .2 1kg,试验组比对照组少损失 3.2 1kg ,两者之间差异显著 (P <0 .0 5 )。从 2个月的补饲结果计算出补饲 1kg营养舔砖能够获得 0 .2 7kg增重。 相似文献
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《科技视界》2015,(8)
This article describes three algorithms for distance field generation on triangulated model: brute force algorithm, single-threaded algorithm based on spatial partition and multi-threaded algorithm based on spatial partition. Spatial partition algorithm use equidistant network divide the bounding box into equal-sized cubes, calculates the maximum and minimum distances between the sample point and each of the small cubes,taking the minimum value from the maximum distance as the minimum distance from the sample point to the model named d1, comparing d1 with the distance from sample point to every little cube's minimum distance d2, if d1 d2, the sample point's distance to all triangles inside this cube are greater than d1, skip this cube, otherwise, calculated the distance from the point to all the triangles intersect with the cube, then alternative d1 with the minimum value, circulate all small cubes intersect with the model. Comparing the calculation results, it can be seen that the algorithm about the multi-threaded distance field relative to the other two algorithms in computational speed is greatly improved especially for complex models. 相似文献
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The effects of source and level of dietary NDF on intake, ruminal digestion in situ, ruminal fermentation, and total tract digestion were evaluated in Hereford steers using a replicated 5 x 5 Latin square design. Diets contained 62 to 64% TDN and included 1) 80% control concentrate (contained pelleted ground grains) and 20% timothy hay (traditional diet), 2) 80% control concentrate and 20% alfalfa cubes, 3) 90% control concentrate and 10% cubes, 4) a completely pelleted diet using corn cobs as the primary NDF source, and 5) 80% textured (rolled instead of ground grains) concentrate and 20% hay. Dry matter intake differed (P less than .05) between the traditional and cube diets due to limited acceptance of alfalfa cubes. Increased (P less than .05) ruminal osmolality, total VFA, and NH3 N and lower (P less than .01) ruminal pH in steers fed corn cob and cube diets relative to steers fed the traditional diet were due to preferential consumption of concentrate over supplemental roughage and the resultant rapid fermentation of concentrates. Potentially degradable DM in the traditional diet exceeded (P less than .06) all other diets, resulting in the increased (P less than .10) extent of DM disappearance despite a slower (P less than .05) rate of DM disappearance. Rate of NDF disappearance and all in situ starch disappearance parameters were similar between the traditional, corn cob, and cube diets. All ruminal digestion parameters involving NDF disappearance were similar between hay diets and between cube diets, whereas rate and extent of starch disappearance differed (P less than .05) between hay diets. Although formulation of diets with different sources of dietary NDF did not affect total tract digestion of nutrients, nutrient availability and ruminal fermentation were altered due to dietary differences in sources of dietary NDF and preferential selection of feedstuffs by steers. 相似文献
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Sheep sometimes develop an abnormal behavior termed as wool‐biting when kept in an indoor system; however, little is known about this behavior. As the provided feed type may affect the foraging behavior and repress abnormal behavior in animals, we tested the effect of feed type on repressing wool‐biting behavior in this study. We used hay prepared in three forms, that is hay bales, rolls and cubes. The wool‐biting frequency associated with hay bales was significantly higher than that associated with rolls (P < 0.05) and cubes (P < 0.05); however, there was no significant difference between rolls and cubes. For hay rolls, wool‐biting significantly decreased after feeding (P < 0.05), suggesting that rolls may provide sheep with appropriate oral stimulation; thus, decreasing the post‐feeding oral abnormal behavior. An individual difference of wool‐biting behavior between sheep was also detected, and an unexpected bed‐eating behavior was found in the hay cube treatment. We suggest that sheep performing movements that are similar to their natural foraging behavior while grazing would repress wool‐biting behavior, which happened in hay roll and hay cube treatments. Considering sanitation and animal welfare, providing sheep with hay rolls may provide an easier method to control wool‐biting behavior in housed sheep. 相似文献
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W. F. H. Ansell 《African Zoology》2013,48(1):97-113
Only one large yellowfish species occurs in the Hardap Dam, apparently closely related to Barbus kimberleyensis. Though smaller than this species in the Vaal River, it is nevertheless a valuable and abundant angling fish. After maturity, reached in females at 26 cm and in males at 18 cm fork length, females outnumber males by 9 :1 beyond 30 cm. Main spawnings occur between February and April, some four months later than in the Vaal River, being correlated with peak seasonal rains in both cases. A minor spawning later in the year is usual, with improved fry survival due to warmer weather conditions reducing the winter mortality of the earlier spawned young. Breeding sites are probably in lentic gravelly-bottomed areas within the dam. Egg production increases from 5-6 000 in 30 cm fish to ca 47 000 in 60 cm females, with strong relationship between cube of fish length and fecundity. 相似文献
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The QT interval and heart rate were measured from the electrocardiogram of 1608 Alderley Park beagles, and the mean QT intervals for 28 values of heart rates between 84 and 192 beats per minute were calculated. These were analysed by linear regression and ranked by Pearson's correlation coefficient for each of eight equations, all of which have been proposed to describe the relationship between QT interval and heart rate. The equation QT=b(square root RR), upon which the calculation of QTc using Bazett's formula is based, did not adequately describe the relationship. QT=b(cube root RR) was a more adequate one-parameter equation. The first-ranked equation was 1/QT=a+b(HR), but its use presents practical and interpretational difficulties; consequently, the second-ranked equation, QT=a+b(log(e)HR), is recommended for routine use. 相似文献
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为确定鸡轮状病毒感染的病理变化特点,对自然发病和人工发病轮状病毒感染鸡进行了病理学研究。结果表明,该病特征性的病理剖检变化为肠黏膜脱落出血,呈卡他性炎症表现。特征性组织学变化为小肠绒毛显著缩短,肠腺深度增加;除肠绒毛缩短外,肠上皮还变为扁平或立方形,并伴发坏死、脱落,黏膜充血、水肿与淋巴细胞浸润。电镜观察,肠黏膜上皮细胞的线粒体肿胀,嵴变粗,排列紊乱;粗面内质网及滑面内质网均扩张呈圆形,粗面内质网表面的核糖体部分脱落,胞浆内游离的核糖体减少。 相似文献
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Sensitivity of the breeding values for growth rate and worm egg count to environmental worm burden in Australian Merino sheep 下载免费PDF全文
Baukje L. Hollema Piter Bijma Julius H. J. van der Werf 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(5):357-365
The objective of this study was to explore the sensitivity of breeding values for growth rate and worm egg count (WEC, cube root transformed) to environmental worm burden, measured as the average WEC for each contemporary group (CGWEC). Growth rate and WEC were measured on 7,818 naturally infected Merino lambs in eight flocks across Australia, linked through common use of AI sires. Through bivariate analysis, genetic correlations of 0.55 ± 0.23 and 0.30 ± 0.16 were found for growth rate and WEC between low and high CGWEC, respectively. In a second analysis, breeding values for growth rate and WEC were regressed on CGWEC with a random regression model. The heritability for growth rate varied from 0.23 to 0.16 from low to high CGWEC, and the heritability for WEC varied from 0.25 to 0.36. Results suggest that breeding values for both growth rate and WEC are sensitive to environmental worm burden. Animals expressed less genetic variation for growth rate and more genetic variation for WEC in high CGWEC than in low CGWEC. This form of genotype‐by‐environment interaction should therefore be considered in genetic evaluation of both growth rate and WEC, to increase the efficiency of selection for animals that are more parasite resistant and more resilient to environmental worm challenge. 相似文献
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Blood-sucking dipterous insects, milk yield losses caused by these insects to cows in the pasture and the possibilities of cattle protection against these insects were investigated in the Leningrad region of the USSR in 1982-1984. The invasion by horse-flies causes the greatest trouble to grazing cattle. Twenty-five horse-fly species were identified during the study. The nine prevailing species constituted more than 85% of the horse-flies invading the animals. The horse-flies flew for 50-55 days from the beginning of June to the beginning of August; mass flights were observed for two weeks starting in the second decade of June. A twelve-hour repelling action was recorded in the Oxamate repellent applied as 20% emulsion. A new portable motor-powered aerosol sprayer was tested during the study. The losses in milk yields caused by horse-flies in the Leningrad region were computed; in the period of the horse-fly flights the milk yields are reduced by 13%. The economic benefit of the treatment of the animals with the Oxamate repellent was 9.11 roubles per rouble invested. Manitoba-type traps attracting the horse-flies to an optical bait (a black ball or cube) were used as an additional method of reducing the occurrence of horse-flies in the pasture. 相似文献