玉米浸泡和粉碎对绵羊日粮消化的影响

【目的】比较浸泡和粉碎2种不同加工方式的玉米粒对绵羊的自由采食和消化的影响。为提高绵羊对玉米颗粒的消化和饲养提供参考依据。【方法】选取6只3岁、体重为(55.0±3.8)kg的健康小尾寒羊公羊,随机分为3组,每组2只。按照3×3拉丁方设计,在3个试验期给各组绵羊分别饲喂组成相同(70%混合精料+30%粉碎玉米秸秆,其中玉米含量55%)、但玉米处理不同的日粮(1、2和3),即整粒玉米为对照组(日粮1)、粉碎玉米(日粮2)、浸泡60~72 h的整粒玉米(日粮3)。【结果】3种日粮的干物质自由采食量分别为(1 566.9±121.6)、(1 579.6±98.5)和(1 466.1±101.2)g/羊/d,日粮3比日粮1和2分别显著降低6.4%(P<0.05)和7.2%(P<0.05)。干物质表观消化率分别为(57.92±0.63)、(62.63±0.53)和(66.39±0.75)%,日粮3比日粮1和2分别显著增加14.6%(P<0.05)和6.0%(P<0.05)。干物质消化量分别为(907.5±59.4)、(989.3±92.5)和(953.4±78.5)g/羊/d,日粮3比日粮1和2分别显著增加5.0%(P<0.05)和减少3.6%(P<0.05)。但日粮3和日粮2比日粮1粗纤维消化率和消化量均无显著差异(P > 0.05)。【结论】日粮中使用浸泡玉米饲喂绵羊会降低绵羊的自由采食量,但同时会提高绵羊的表观消化率,表明浸泡玉米饲喂更有利于促进绵羊的消化。     

安格斯牛与西藏犏牛杂交生产肉牛试验初报

[目的]犏牛可以生活在海拔2 800~4 200 m,对高寒缺氧的生态环境具有很强的适应能力,是“世界屋脊”的著名牛种,为了提高西藏犏牛资源的综合利用,其后代变废为宝。[方法]在试验区选择200头经产母犏牛通过引进安格斯牛的细管冻精,依靠人工授精技术,应用种间三元杂交技术生产优质商品肉牛试验,测定初生、3月龄的体重、体尺指标,观察高寒气候的适应性。[结果]结果显示:参配母犏牛200头,实配160头,其中104头母犏牛怀孕受胎,98头顺利产犊。实配率80%,人工授精受胎率65%,成活率94.23%。犏牛平均妊娠期(266.81±11.93) d。安格斯与西藏犏牛杂交后代的出生体尺、体重与传统杂交犊牛(多勒)相比,平均体重增加8.95 kg,提高73.23;体高、体斜长、胸围、管围平均分别比传统杂交犊牛(多勒)增加7.491 cm,1.394 cm,8.998 cm,0.063 cm,提高了13.94%,2.56%,15.70%,0.068%。安格斯与西藏犏牛杂交后代的3月龄与传统杂交犊牛(多勒)相比,平均体重增加43.3 kg,提高168.89;体高、体斜长、胸围、管围平均分别比传统杂交犊牛(多勒)增加15.67 cm,16.95 cm,26.31 cm,1.64 cm,提高23.27%,24.76%,34.31%,15.83%。[结论]弥补了犏牛传统杂交后代普遍存在的体躯发育差、生长发育慢等缺陷,且很好地适应西藏高寒生态环境和管理条件,杂种优势十分明显,因此安格斯牛可作为高原环境下繁殖犏牛生产肉牛的理想父本品种使用,并拥有开发高端产品的巨大潜力。     

14个鲜食葡萄品种在河北承德的引种表现

为筛选出适宜在河北承德地区栽培的优良鲜食葡萄品种,以满足消费者需求,提高种植户经济效益,优化当地鲜食葡萄种植结构,对京亚、醉金香和绿玫香等14个鲜食葡萄品种进行引种试验。试验采用田间调查与室内测试相结合的方法,包括观察记录各供试品种的物候期和生长特性,测定果实的理化成分,评价果实的感官质量。结果表明,卓越玫瑰、蜜光、巨茉莉、醉金香和绿玫瑰5个鲜食葡萄品种栽培性状和果实品质最佳,可作为中早熟品种承德推广种植,金光和摩尔多瓦不适宜在承德露地推广种植。     

基于Sentinel-2卫星数据的灌区农田土壤水盐协同反演

土壤含水量（soil water content, SWC）和土壤含盐量（soil salt content, SSC）是影响作物生长和农业生产力的重要因素。光学卫星图像已成为SWC和SSC估计的主要数据源。然而,在SWC或SSC变化较大地区,土壤水分和盐分会影响对方对光谱反射率的响应,使得SSC和SWC的反演精度较差。对此,该研究提出了一个半解析性的反射率模型—RVS模型,来模拟植被光谱反射率（R_v）对作物根区土壤含水量和含盐量的响应;并通过构建的RVS模型,对植被覆盖区域的土壤含水量和土壤含盐量进行同步监测。研究表明：RVS模型在反演研究区土壤含盐量和含水量时,精度较为可靠(水分：决定系数R²为0.63～0.74,均方根误差为0.017～0.028;盐分：决定系数R²为0.68～0.75,均方根误差为0.0525～0.0617)。在作物生长过程中,植被光谱反射率对深层土壤的含水量和含盐量的响应比对浅层土壤的含水量和含盐量的响应更加明显,而且随着作物的生长,影响光谱反射率的主导因素从土壤水分慢慢转向土壤盐分和水盐相互作用。该研究在一定程度上揭示了土壤水分、盐分、水盐交互作用对作物光谱反射率的干扰过程,实现土壤水分和盐分的同步监测,对实现区域尺度上土壤含盐量和含水量的精准监测具有一定的意义。     

Late onset cerebellar cortical degeneration in a koala

A 10-year-old male koala started to fall from the tree while sleeping. Subsequently, the koala often fell down while walking and showed a gait abnormality, abnormal nystagmus and hypersalivation. At 12 years of age, the koala became ataxic and seemed blind. At 13 years of age, the koala exhibited signs of dysstasia and was euthanased. Necropsy revealed marked symmetrical atrophy of the cerebellum. Histopathologically, a severe loss of Purkinje and granule cells was evident in the cerebellum, while the molecular layer was more cellular than normal with cells resembling small neurons, which were positively stained with parvalbumin immunohistochemistry. Reactive Bergmann glial cells (astrocytes) were present adjacent to the depleted Purkinje cell zone. The very late onset and slow progression of the cerebellar cortical degeneration in this case is particularly interesting and appears to be the first report in the koala.     

Clinical trial of efficacy of ivermectin pour‐on against gastrointestinal parasitic nematodes in silvopasturing horses

The aim of this study was to assess, by a clinical trial, the efficacy of an ivermectin‐based pour‐on treatment against gastrointestinal parasitic nematodes in naturally infected horses using 2 groups of mature indigenous Pura Raza Galega grazing mares. Faecal and blood samples were collected individually over a 21 week period. Faeces were analysed by the coprological flotation, sedimentation and migration techniques. Changes in circulating blood cells were monitored over the study period. The administration of the ivermectin suppressed the eggelimination of ascarids and pinworms throughout the study and no strongyle‐eggs were observed in the treatment group between the 3rd and 10th weeks. The numbers of red cells increased significantly after the anthelmintic therapy, and a statistical reduction in circulating leucocytes was recorded. No side effects were observed. The pour‐on ivermectin formulation was highly successful against gastrointestinal nematodes and appears to be a useful therapeutic routine for large groups of horses.     

Interobserver Repeatability of Measurements on Computed Tomography Images of Lax Canine Hip Joints from Youth to Maturity

Objectives— To determine interobserver repeatability of measurements on computed tomography (CT) images of lax canine hip joints at different ages and in the presence of degenerative joint disease at maturity. Study Design— Longitudinal observational investigation. Animals— Sibling crossbreed hounds. Methods— Pelvic CT was performed at 20, 24, 32, 48, 68, and 104 weeks of age. Measures were performed on 3 contiguous two‐dimensional (2D) transverse CT images of both hips at each time point by 3 investigators. Center‐edge angle (CEA), horizontal toit externe angle (HTEA), ventral (VASA), dorsal (DASA), and horizontal (HASA) acetabular sector angles, acetabular index (AI), and percent femoral head coverage (CPC) were measured. Interobserver repeatability was quantified with the intraclass correlation coefficient (ICC). Satisfactory repeatability was considered when ICC≥0.75. Results— DASA, CEA, and CPC were repeatable in all age groups. HASA and HTEA were repeatable for all but 1 time point. At 20 weeks of age, all measures but AI were repeatable, and at 104 weeks of age, DASA, CEA, CPC, and HASA were repeatable. Measures were repeatable in hips with and without degenerative changes with the exceptions of AI and HASA in normal hips and VASA and HTEA in osteoarthritic hips. Conclusions— Most 2D CT measurements examined were repeatable regardless of age or joint disease. Clinical Relevance— Two‐dimensional CT measures may augment current techniques for assessing joint changes in lax canine hips.     

Effects of CIDR-G and Melatonin Implants, and their Combination on the Efficacy of Oestrus Induction and Fertility of Kilis Goats

The objective of this study was to compare the efficiency of oestrus induction protocols on Kilis dairy goats kept on a goat farm situated close to Kilis, Turkey. Eighty goats were assigned randomly into four groups of 20 animals each in a factorial arrangement: (i) untreated control (CON), (ii) melatonin implant (MEL), (iii) CIDR-G (CIDR) and (iv) melatonin implant plus CIDR-G (MC). Experiments were performed in mid-anoestrus season under natural photoperiod environment. The differences among treatment groups in oestrus response were significant. Oestrus response was higher in the MC group than in other groups (p < 0.05). A significant difference was observed in the time interval from cessation of treatment to the onset of oestrus among treatments. The CIDR-G treatment reduced intervals from buck introduction to oestrus. The time to onset of oestrus in both the MC and CIDR groups was significantly shorter, compared with the MEL and CON groups (p < 0.05). The number of does kidding and fertility were not different among treatment groups (p > 0.05). Fecundity was similar among goats in all groups. Prolificacy and twining rates showed similar trends as fecundity rates, with no differences (p > 0.05) between treatments. The results of this study showed that oestrus in Kilis does can be effectively induced by using melatonin and CIDR combined treatment, and fertility will not be adversely affected. However, this treatment did not improve fecundity, prolificacy and twining rates.     

猪乳糖酶基因启动子及增强子的活性研究

采用PCR、TA克隆、构建pGL3.0 Basic荧光素酶报告基因载体并转染Caco-2细胞、Dual-Glo萤光素酶检测系统检测细胞系中荧光信号值的方法分析猪乳糖酶基因不同基因型的启动子与增强子活性。结果表明:GA型启动子和CG型启动子相比差异极显著(P=0.001),CG型启动子能显著促进猪LCT基因表达,而GA型启动子不能促进基因表达。A型增强子,可以使GA型启动子活性显著增强(P<0.05),使CG型启动子活性显著降低(P<0.01);G型增强子对GA型启动子或CG型启动子,均起显著的抑制作用(P<0.01)。猪LCT增强子和启动子多态性位点组合形成的单倍型促进基因表达的作用从高到低顺序为:A型增强子+GA型启动子>A/G型增强子+CG型启动子>G型增强子+GA型启动子。