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31.
32.
A study of parturient calf mortality in a herd of 250 Shorthorn cattle on the Southern Tablelands of New South Wales is reported. Death rates as high as 44% from heifer groups are described. There were 30 parturient deaths of which 27 were confirmed as due to maternal dystocia. Pathological changes in many of the dystocia-caused deaths were minimal, but a congested, swollen tongue was a definitive lesion. The death rate was not significantly higher in heifers mated at 14 to 16 months of age than in those mated at 20 to 22 months, but significantly more male than female calves died from maternal dystocia. As two dead calves were affected with goitre, a comparative trial using parenteral iodine was designed. Ratios of thyroid weight to calf body weight were examined for 24 of the calves where the mean was 0.52 gm/kg. Goitre was found not to be a contributing factor to the calving mortality problem. The use of a Jersey bull for heifer matings eliminated the dystocia problem. The Jersey cross allowed safe, early mating at 14 months of age. 相似文献
33.
MJ Thompson J Toomre ER Anderson HM Antia G Berthomieu D Burtonclay SM Chitre J Christensen-Dalsgaard T Corbard M DeRosa CR Genovese DO Gough DA Haber JW Harvey F Hill R Howe SG Korzennik AG Kosovichev JW Leibacher FP Pijpers J Provost EJ Rhodes J Schou T Sekii PB Stark PR Wilson 《Science (New York, N.Y.)》1996,272(5266):1300-1305
Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes. 相似文献
34.
ER JOHNSON 《Australian veterinary journal》1996,73(6):225-232
A progeny testing system to measure beef carcase merit, the Abtech Test, has been developed. Nine carcase characteristics are measured objectively at a slaughter age of 300 days on the carcases of 12 steer progeny per sire. Five carcase characteristics were used to quantify the carcase, namely, carcase composition as submitted, carcase composition (adjusted to 20% total carcase fat), estimated lean meat yield (adjusted to 20% total carcase fat), muscle-bone ratio (adjusted to a common muscle plus bone weight), and eye muscle volume index (adjusted for total carcase muscle weight). Four carcase measurements used to describe quality were evaluated: eye muscle area at the 10th rib (adjusted for total carcase muscle weight), marbling of the eye muscle at the 10th rib (chemically determined and adjusted to 20% total carcase fat), muscle texture at the 10th rib (mean muscle bundle diameter) and fat colour (determined on intermuscular fat at the 10th rib under standard conditions).
It is proposed that this testing system could be used for the genetic improvement of beef carcases. 相似文献
It is proposed that this testing system could be used for the genetic improvement of beef carcases. 相似文献
35.
为了探索适宜的玉米黄素双棕榈酸酯(ZDP)乳液制备工艺,通过高压均质方法,采用2种天然乳化剂:大豆卵磷脂(SL)和乳清分离蛋白(WPI)和4种合成乳化剂:十聚甘油单油酸酯(PGE18)、十聚甘油单月桂酸酯(PGE12)、蔗糖酯(SE15)和吐温80(T80),以及2种不同油相:大豆油(SO)和中链甘油三酯(MCT),分别制备了ZDP乳液,研究了不同乳化剂种类和质量分数以及油相种类对ZDP乳液性质和稳定性的影响。同时,在最佳乳化剂条件下,研究了ZDP添加量对乳液性质的影响。研究结果表明:天然乳化剂乳化制备所得ZDP乳液平均粒径大,且稳定性一般。小分子合成乳化剂制得的ZDP乳液平均粒径小,但稳定性差异大。其中,PGE18为乳化剂时制备的乳液各项指标较好,且在质量分数为0.8%时乳化效果最好。MCT为油相较SO为油相制备所得乳液稳定性好。因此,选择质量分数为0.8%的PGE18为乳化剂,MCT为油相,高压均质可以制得粒径小于200 nm的ZDP乳液,且在4℃下贮藏28 d仍可保留约90%的ZDP。ZDP添加量变化在4~32 nmol/g时对ZDP乳液的粒径和电位无显著影响。 相似文献
36.
ER da Cunha CF Martins CG Silva HC Bessler SN Báo 《Reproduction in domestic animals》2014,49(5):806-812
The objective of this work was to study cellular types that did not participated in the gastrulation process, amniotic fluid cells (AFCs) and umbilical cord cells (UCCs), in conditions of long‐term culture and cryopreserved with different solutions. The AFCs and UCCs were used in a comparative study with ear fibroblast cells (EFCs) that were cultured in vitro until 20 cellular passages and cryopreserved in 10% dimethylsulphoxide (DMSO), 5% dimethyl formamide (DMF) and 7% glycerol (Gly) solutions. The cellular viability, ultrastructure, DNA fragmentation and chromosome stability were evaluated to determine the cellular type most resistant. In all cell types, it was possible to evaluate the AFCs until 15 passages and UCCs until 20 passages with different periods of cellular growth to reach the confluence phase. Solutions containing 10% DMSO ensured viability of 90.33 ± 5.58%, 90.56 ± 4.40% and 81.90 ± 3.31%, respectively for EFCs, AFCs and UCCs, being significantly more efficient and with less variation than other cryoprotectant solutions. The AFCs were more sensitive to cryopreservation and presented low viability rate at the passage 20 (17.2 ± 8.87%). There was no change in karyotype and nuclear fragmentation was low in all cellular passages studied. With the scanning electron analysis was possible the characterization of AFCs and UCCs in suspension. The three cellular types of cells presented different shapes and characteristics on the surface. The results demonstrate that bovine AFCs and UCCs can be isolated, cultured in vitro and cryopreserved in 10% DMSO, not causing damage to DNA and chromosomes. The UCCs were more resistant than AFCs in all aspects. 相似文献
37.
近年来,以往不被木材加工行业和广大消费者群体接受和认可的数以百计的木制品之中的小产品——木皮,越来越受到生产和加工木材制品的企业欢迎与青睐,而且逐渐在市场上经受住了考验与洗礼。从我国东南沿海及许多大中型城市的木材制品的销售情况来看,凡是使用了木皮作为贴面的产品,都要受到市场的热捧,尤其是天然木皮产品更是待遇有加。正因为拥有了广大消费者也就是消费市场的“准入证”和“通行证”, 相似文献
38.
William J Meadus Tyler D Turner Michael ER Dugan Jennifer L Aalhus Pascale Duff David Rolland Bethany Uttaro Lorna L Gibson 《畜牧与生物技术杂志(英文版)》2013,4(1):46
Pork is traditionally low in docosahexanoic acid (DHA, C22:6n-3) and deficient in omega-3 fats for a balanced human diet. DHA as triglycerides was commercially prepared from the microalgae Schizochytrium and injected into fresh pork loins. Treatments of a mixed brine control (CON), 3.1% sunflower oil in mixed brine (SF) and a 3.1% DHA oil in mixed brine (DHA) were injected into pork loins at 10 mL/100 g and grilled at 205°C. After cooking, the CON and SF pork loins contained 0.03 to 0.05 mg DHA/g of pork and the DHA injected loins contained approximately 1.46 mg DHA/g. This also changed the fatty acid profile of omega-6: omega-3 from, 5 to 1 in the CON pork, to a ratio of 1.7 to 1 in DHA pork. The appearance, odor, oxidation rates and sensory taste, as judged by a trained panel, determined the DHA injected meat to be, ''slightly desirable’ and gave lower ''off flavour’ scores, relative to the CON and SF injected pork. Pork can be fortified with DHA oil to 146 mg/100 g serving, which would meet half the recommended daily omega 3 fatty acid requirements for adult humans and would be desirable in taste. 相似文献
39.
F Hill PB Stark RT Stebbins ER Anderson HM Antia TM Brown TL Duvall DA Haber JW Harvey DH Hathaway R Howe RP Hubbard HP Jones JR Kennedy SG Korzennik AG Kosovichev JW Leibacher KG Libbrecht JA Pintar EJ Rhodes J Schou MJ Thompson S Tomczyk CG Toner R Toussaint WE Williams 《Science (New York, N.Y.)》1996,272(5266):1292-1296
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure. 相似文献
40.
据统计,以我国每年新增的大约10亿m2的商品房建筑面积,加之旧房改造装修大约5亿m2的面积,其中室内门占10%,而各类木质门又为其中的70%的数量计算,几乎潜在有超过1亿m2木门需求的巨大市场. 相似文献