Effect of selenium supplementation on semen characteristics of Brazil's ram

The aim of this study was to investigate the effects of different concentrations of oral supplementation with selenium (Se) upon ram sperm parameters. Thirty rams managed in stall under intensive system were used and divided into five groups (six animals per group) as follows: control group (G1) mineral mixture supplementation without Se, group 2 (G2) mineral mixture supplemented with 5 mg/kg Se, group 3 (G3) supplemented with 10 mg/kg Se, group 4 (G4) supplemented with 15 mg/kg Se and group 5 (G5) supplemented with 20 mg/kg Se. For each group, there was an adjustment period of 14 days. The experimental period was 350 days. Every 56 days, the animals were weighed and semen samples were collected by electroejaculation. Semen analysis included volume, mass moviment, total motility, vigour, concentration and morphology. For plasmatic and acrosomal membrane integrity evaluation and mitochondrial membrane potential were used a combination of fluorescent probes. Differences between means values obtained by analysis of variance were verified by Tukey test with 5% probability. There was no statistical difference between treatment groups in relation to volume, mass moviment, total motility, vigour, concentration, plasma and acrosomal membrane integrity (p > .05). Sperm morphology was different between treatment groups, the G1 (0 mg of selenium) had the highest percentage of major defects (11.11 ± 1.11^a; p < .05). It was concluded that selenium decrease the percentage of sperm defects and did not directly influence on ram sperm volume, mass moviment, total motility, vigour, concentration and membrane integrity.     

黄芪对育肥绵羊生长及产肉性能的影响

为探寻育肥绵羊日粮中黄芪(Astargalus membranaceus)适宜的添加量,将36只3月龄体重相近广灵大尾羊公羔随机分成6组,对照组、I、II、III、IV和V处理组分别喂给基础日粮+0%,0.5%,1%,1.5%,2% 和3%黄芪。试验期70 d,考察其生长及产肉性能。结果显示:试验结束时II组活体重显著高于对照组、III组和IV组(P<0.05),极显著高于V组(P<0.01)。II组绵羊30 d和60 d日增重显著高于其他处理组和对照组(P<0.05),II组料重比极显著低于IV组和V组(P<0.01),显著低于C组和III组(P<0.05)。II组胴体重和净肉重极显著高于 IV组、V组和对照组(P<0.01),显著高于I组和III组(P<0.05);胴体分割后II组羊肋脊排和带臀腿重显著高于其他处理组和对照组(P<0.05)。育肥绵羊日粮中添加1%黄芪可显著提高日增重,提高饲料利用率,增加优质肉块的比例。     

小尾寒羊种公羊的培育

2005年对经培育的102只小尾寒羊公羊测定,成年种公羊平均体重102.8kg,周岁公羊体重75kg,6月龄公羔体重42.32kg,3月龄公羔体重24.19kg,较培育前2003年分别提高了12.94,8.87,11.07和5.82kg(P<0.01)。     

条中32号生理小种对小麦成株期致病性的初步研究

为了给小麦育种提供抗源材料及为生产中筛选抗务锈品种提供依据,以33个小麦常规品种、区试品系为材料,对务中32号生理小种的成株期致病性进行了研究。结果表明,供试小麦品种(系)中近1／2品种(系),包括部分慢锈品种对务中32号均表现高感,但慢锈品种的严重度比较轻;含有小麦亲缘种属染色体片段的一些材料,如含有中间偃麦草染色体片段的M8007等,含有长穗偃麦草染色体片段的9322、西农291等,含有偏凸山羊草染色体片段的贵农775等,对条中32有较好的抗病能力,这些材料可作为杂种小麦改良亲本抗病性以及常规品种选育的中间种质材料加以利用。