驼绒藜属牧草种苗耐盐性评价及生理基础研究

对7份驼绒藜属材料种子萌发及幼苗进行耐盐性研究。结果表明,种苗具有较高的耐盐性,在种间及种内生态型间存在差异,其中华北驼绒藜耐盐性最强,其次为华北驼绒藜科尔沁生态型,驼绒藜荒漠生态型和心叶驼绒藜耐盐性最弱。种苗的耐盐能力和种子的活力呈正相关,在恶劣生境条件下形成的种子活力较低,种苗的耐盐力也较低;种苗耐盐半致死浓度与种子活力3项指标呈显著或极显著正相关(r=0.82^*、0.93^**、0.90^**)。而盐性生理基础的研究结果表明,种子耐盐性的指标与种子含氮量呈极显著正相关(r=0.88^**、0.90^**),与种子含磷量呈正相关(r=0.77、0.68),与含糖量相关性较小(r=-0.33～0.55)。初步认为种子耐盐半致死浓度、种子活力指数和含氮量可以作为种子耐盐性评价和选育的生理指标。     

Effect of Different Dietary Nutrition Levels on Fattening Effect of Holstein Bulls

This experiment was conducted to study the effect of different dietary nutrition levels on fattening effect of Holstein bulls.48 4-month-old Holstein bulls with an average body weight of 128 kg were allocated into two groups,group Ⅰ was fed a low nutrition level diet,group Ⅱ was fed a high nutrition level diet.Each group had 24 Holstein bulls.The pre-test period lasted for 7 days and the trial period lasted for 245 days.The results showed that compared with group Ⅰ,the ADG in group Ⅱ was significantly increased by 6.36% (P<0.01),while the F/G in group Ⅱ was decreased by 6.55%.With the increasing of dietary nutrition levels,the apparent digestibility of CP,EE,NDF,ADF,Ca and P were rising,but there was no significant differences between two groups (P>0.05).Compared with group Ⅰ,the serum GLU,AST,ALT and GH contents in group Ⅱ were increased by 12.52%,12.85%,9.68% and 13.24% (P<0.05),respectively,while the serum BUN content in group Ⅱ was decreased by 10.98% (P<0.05).Compared with group Ⅰ,the feeding profits of group Ⅱ increased by 1.37 yuan/(head·day),the total economic benefit of group Ⅱ increased by 335.65 yuan/head.In conclusion,the improvement of dietary nutrition levels could improve the fattening performance and the economic benefit of Holstein bulls.     

野菊嫩茎的组织培养

在适宜的培养条件下,利用野菊花的嫩茎作为外植体,用组织培养的方法,在MS培养基上生长良好,获得再生植株.练苗后,成活率达100%,生长势强,茎粗壮叶色浓绿.结果表明:利用组织培养的方式对野菊花进行扩繁,简便易行.     

Low Fertility in Daughters of Bulls with 1/29 Translocation

Non-return rates at different stages after insemination were compared in daughters (n = 21,212) of five translocation heterozygous sires with all cows and heifers (n = 610,714) represented in the Norwegian Red Cattle (NRF) breeding statistics during the period October 1970 to September 1972. The daughters of the carrier bulls showed statistically significant lower non-return rates for 0–30, 30–60, 60–90, 90–120, 120–150, 150–180 and 180–270 days as compared with the control animals. The decline in non-return percentage for the daughters of translocation sires was greater than in the control animals during the period from 0–30 to 60–90 days indicating higher losses of fetuses during the early period after insemination.Daughter groups of carrier bulls consisting of adult cows only showed higher non-return rates than groups comprising both cows and heifers.     

N-氨甲酰谷氨酸对荷斯坦奶公牛生长性能、瘤胃发酵及微生物区系和甲烷排放量的影响

本试验旨在研究添加不同水平的N-氨甲酰谷氨酸（N-carbamylglutamate,NCG）对荷斯坦奶公牛生长性能、瘤胃发酵、瘤胃微生物区系和甲烷排放量的影响。试验选择45头健康、体重相近（（478±13.66）kg）的荷斯坦奶公牛,随机分成3组,每组15头,每头分别添加0 g·d^-1（Ⅰ组,对照）、15 g·d^-1（Ⅱ组）、25 g·d^-1（Ⅲ组）的NCG。预试期7 d,正试期90 d。结果表明：1）与对照组相比,饲喂15 g·d^-1和25 g·d^-1 NCG的公牛饲料转化效率分别改善6.91%（P<0.01）和7.91%（P<0.01）;2）与对照组相比,饲喂15 g·d^-1和25 g·d^-1 NCG的公牛瘤胃微生物蛋白的浓度显著升高了22.91%和15.17%（P<0.01）;随着NCG的增加,丙酸浓度显著线性升高（P<0.01）,且15 g·d^-1 NCG组最高;3）从瘤胃产甲烷古菌属水平的相对丰度上分析,25 g·d^-1的公牛甲烷短杆菌属最低,其相对丰度为80.05%;随着NCG的增加,甲烷球菌属、甲烷丝状菌属的相对丰富度显著下降（P<0.01）;4）添加不同水平的NCG均显著降低了甲烷的排放量,饲喂15和25 g·d^-1 NCG公牛甲烷排放量分别比对照组降低了8.44%和10.51%（P<0.01）。综上,在本试验条件下,添加NCG能有效调控荷斯坦奶公牛瘤胃发酵,提高饲料转化效率,降低甲烷排放量。推荐添加量为15 g·d^-1。     

大麦不同品种不同播期幼穗分化时期形态诊断研究

 大麦幼穗分化进程与植株外部形态关系密切,1997年对5个大麦品种(品系)、不同播期的幼穗分化与叶龄、叶龄余数和叶枕距的关系进行了初步研究。结果表明,同一品种不同播期幼穗分化各阶段的叶龄基本一致,不同品种同一播期幼穗分化各阶段的叶龄有明显差异,弱春性品种主茎总叶数较多,幼穗分化起步迟,进程慢,春性品种主茎叶数较少,幼穗分化起步早,进程快。应用叶龄、叶龄余数和叶枕距等指标来判断幼穗分化各阶段,对于采取相应的栽培技术措施、促进小穗分化和小花发育都有重要意义。     

Evaluating Domestic Sheep Survival with Different Breeds of Livestock Guardian Dogs

Livestock guard dogs (LGDs; Canis familiaris) have been widely adopted by domestic sheep (Ovis aries) producers because they reduce predation by wild carnivores. LGDs were originally used in the United States to reduce coyote (Canis latrans) depredations, but their efficacy against a suite of large carnivores, including wolves (Canis lupus), brown bears (Ursus arctos), black bears (Ursus americanus), and cougars (Puma concolor), and whether specific breeds perform better than others remains unclear. To assess breed-specific effectiveness at reducing depredations from a suite of livestock predators, we compared survival rates of sheep protected by different breeds of LGDs, including three breeds from Europe (Turkish kangal, Bulgarian karakachan, and Portuguese cão de gado transmontano) and mixed-breed LGDs, “whitedog,” common in the United States. With the help of participating sheep producers, we collected cause-specific mortality data from domestic sheep in Idaho, Montana, Oregon, and Wyoming between 2013 and 2016. All three of the novel breeds of LGD tested were associated with overall reductions in sheep depredation relative to whitedogs, ranging from 61% to 95% (P < 0.05). In terms of predator-specific effectiveness, the Turkish kangal was associated with decreases in depredation from cougars (e^β = 0.31, 95% CI = 0.10–0.94, P = 0.04), black bears (e^β = 0.33, 95% CI = 0.28–0.37, P < 0.01), and coyotes (e^β = 0.56, 95% CI = 0.35–0.90, P = 0.02). The Bulgarian karakachan was associated with a decrease in coyote depredations (e^β = 0.07, 95% CI = 0.01–0.49, P < 0.01). The Portuguese transmontano was not associated with significant reductions in depredation hazard for any specific predator. Although variations in breed-specific effectiveness were subtle and nuanced, these findings will help livestock producers and wildlife managers make tailored decisions about how best to incorporate different breeds of LGD into sheep grazing regimes.     

几种抗球虫药物对獭兔球虫感染和幼兔生长性能的影响

在福建省福安市某獭兔场共检测出16种艾美耳球虫,均为混合感染。选取210只断乳1周、球虫卵囊阳性的獭兔幼兔,随机分为7组,进行抗球虫药物试验。在抗球虫药物试验组中,2.5%妥曲珠利组的獭兔幼兔按有效剂量30 mg/kg体重、5%肠球双效(盐酸氨丙啉+胺喹噁啉钠)组和5%优球乐(癸氧喹酯)组按有效剂量50 mg/kg体重灌服,分为1次用药组和2次用药组;对照组灌服等量生理盐水。结果显示,妥曲珠利组獭兔幼兔用药后第1周,粪便中的球虫卵囊数(OPG值)比用药前减少78.39%,也显著低于其他药物组和对照组(P<0.01);用药后第2周,球虫OPG值比用药前减少88.35%,感染率也降至最低;用药后第8周,粪便中球虫OPG值比用药前减少92.99%。至用药后第8周,各试验组与对照组獭兔幼兔球虫OPG值均转归为相对较低水平,感染率则仍保持较高水平;妥曲珠利组獭兔幼兔死亡率显著低于对照组(P<0.05),其他组间死亡率差异不显著;其平均增重显著高于对照组(P<0.05),料重比则显著低于对照组(P<0.05)、极显著低于5%肠球双效1次用药组(P<0.01)。     

白藜芦醇对奶牛性控冻精品质和体外受精能力的影响

本研究旨在探究不同浓度白藜芦醇处理对奶牛性控冻精品质和体外受精能力的影响。在解冻后的奶牛性控冻精中分别添加0、10~(-3)、10~(-4)、10~(-5) mol/L的白藜芦醇,各组精子在受精液中获能孵育1.5 h后,测定精子质量和体外受精能力。结果表明:添加白藜芦醇均可有效降低性控冻精中活性氧(ROS)含量、提高顶体完整活精子比例(P0.05),其中10~(-3)、10~(-4) mol/L的白藜芦醇处理对降低ROS含量最为显著;10-4 mol/L的白藜芦醇处理可显著降低丙二醛(MDA)含量并提高性控冻精的卵裂率和囊胚率(P0.05)。综上所述,白藜芦醇作为一种外源性天然抗氧化剂,通过降低性控精液中过量的ROS水平、抑制精子脂质过氧化反应、保护顶体完整性,从而提高性控精子质量和体外受精能力。     

马蹄金叶片离体培养及植株再生的研究

在不同植物生长调节剂组合、不同培养基条件下,探讨了马蹄金叶片离体培养的方法和影响因素。结果表明,含不同植物生长调节剂组合的培养基对愈伤组织的诱导频率无显著影响,出愈率均达90%～100%;以MS或B5培养基作诱导愈伤组织的基本培养基效果较好;将叶片接种到MS 2mg/L6-BA的诱导培养基中诱导愈伤组织,再用B5 1.5mg/L6-BA 0.5mg/LZT 0.2mg/Lα-NAA作分化培养基出苗效果最佳,愈伤组织分化频率高达20%。