The relationship between carcass characteristics,plasma hormones and metabolites in young fattening bulls

Six Belgian Blue bulls (double-muscled type) and six Friesian bulls were offered a fattening diet for 34 weeks. Plasma samples were obtained once a week and also every 20 min over a 24 h period, 7 weeks before slaughter.No differences were observed between the breeds in plasma glucose, urea and free amino nitrogen concentrations, while creatinine was significantly higher in the Belgian Blue bulls. Tri-iodothyronin, tetra-iodothyronin, insulin-like growth factor 1, insulin and testosterone concentrations were higher in the Holstein group. In contrast, the Belgian Blue bulls appeared to produce more growth hormone. The slaughter weight, carcass weight, dressing percentage and proportion of lean meat were significantly higher in the Belgian Blue group. The characteristics of muscle mass (carcass weight, dressing percentage and proportion of lean meat) were positively correlated with creatinine and with the total peak area or peak amplitude of growth hormone. The insulin concentration was positively correlated with the proportion of adipose tissue in the carcass and negatively correlated with the proportion of muscle. There were no correlations between the carcass characteristics and insulin-like growth factor 1 or testosterone. No further information was provided when the ratios of the hormones were correlated with carcass characteristics.     

短穗兔耳草的克隆生长特征

以调查统计的方法研究了高寒草甸匍匐茎植物短穗兔耳草Lagotis brachystachya无性系的生长特征、形态特征以及能量分配规律,研究结果表明:匍匐茎只有1条的短穗兔耳草最多,占60．47％,匍匐茎有4条的短穗兔耳草只占6．98％。在牧草生长盛期,短穗兔耳草无性系的基株高度4．03 cm,根长为9．11 cm,叶数为7．98;分株高度0．85 cm,根长2．73 cm,叶数为3．08;匍匐茎的茎生叶数为12．54,长度为15.14 cm,匍匐茎比节间重为2．18 mg／cm,粗度为0．97 mm,不同构件的干质量呈现出基株>匍匐茎>分株>茎生叶的规律。随着匍匐茎数目的增多,短穗兔耳萆无性系的基株根长逐渐增加,用于克隆繁殖的能量投资也有增加的趋势,其他参数都没有明显的变化规律。     

Effects of three different concentrate proportions and rapeseed meal supplement to grass silage on animal performance of dairy-breed bulls with TMR feeding

A 3 × 2 factorial design with growing dairy-breed bulls was used to study the effects on animal performance of (1) proportion of concentrate (rolled barley) in the diet, and (2) inclusion of rapeseed meal (RSM) in the barley-based concentrate in a total mixed ration (TMR). The interactions between concentrate proportion and RSM supplement were also examined.Three feeding experiments comprised in total of 84 Finnish Ayrshire bulls and 6 Friesian bulls. The bulls were fed TMR ad libitum. The three concentrate proportions were 300 (L), 500 (M) and 700 (H) g/kg dry matter (DM), fed without RSM (RSM−) or with RSM (RSM+). Rapeseed meal was given so that the crude protein (CP) content of the concentrate was raised to 160 g/kg DM in the RSM+ diets. In the RSM− diets the CP content of the concentrate was 128 g/kg DM, so the CP content increased 25% with RSM supplementation. Increasing the proportion of concentrate led to a linear improvement in daily live weight gain (LWG) (P < 0.05), but there were no significant treatment differences in the DM intake (kg/d). Increasing the proportion of concentrate also led to significantly higher CP (P < 0.001) and phosphorus (P) (P < 0.001) supply and significantly improved DM and organic matter (OM) digestibility (P < 0.001). However, the digestibility of neutral detergent fibre (NDF) decreased (P < 0.001) as the proportion of concentrate increased. The feed conversion rate (kg DM/kg LWG) decreased significantly with increasing concentrate proportion (P < 0.001). Rapeseed meal supplement had no effect on animal performance, but the supply of CP (P < 0.01) and P (P < 0.001) was higher when RSM was included in the diet. The CP (P < 0.001) and NDF (P < 0.05) digestibilities were also higher for the RSM+ diets than for the RSM− diets. Because RSM at the concentration used did not affect animal performance, there is no reason to use RSM supplementation for finishing dairy bulls when there is good quality grass silage and barley-based concentrate in the TMR ration. This study also shows that there is a need to update the Finnish feeding recommendations for dairy-breed growing bulls, and extra calculations are needed for the energy and protein supply of growing dairy bulls.     

Efficacy of probiotics from anaerobic microflora with prebiotics on growth performance and noxious gas emission in growing pigs

We investigated the effect of probiotics from anaerobic microflora with prebiotics (synbiotics) on growth performance, noxious gas emission and fecal pathogenic bacteria populations in growing pigs. The basal diet, which contained approximately 25% corn, 24% whey, 12% wheat and 12% soybean meal, was supplemented alternatively with 0.15% antibiotics (US diet), prebiotics and 0.2% probiotics from anaerobic bacteria (BS diet), yeast (YS diet), mold (MS diet) or compounds (CS diet). One hundred and fifty pigs were fed an experimental diet for 15 days. Although the growth performance was not affected by supplemental synbiotics, the BS group showed higher dry matter and crude protein digestibility. The BS group decreased fecal ammonia and amine gas emissions, and increased fecal acetate gas emission compared with the US group. All synbiotics groups decreased in fecal propionate gas emission. Fecal Escherichia coli population was lower in the synbiotics groups than in the US group. Therefore, the results of the present study suggest that synbiotics exert similar effects with antibiotics on the nutrient digestibility and fecal microflora composition in growing pigs. Moreover, synbiotics can also decrease the fecal noxious gas emission in growing pigs.     

成长型饲料企业人力资源面临的问题及解决策略研究

企业的发展通常要遵循企业的生命周期理论,从企业最初创立进入生存期,到企业规模进一步增大进入成长期,再到企业成熟期和衰退期,每个生命周期阶段的生产经营和管理策略都有所不同.当企业进入成长期,其发展潜力进一步释放,生产销售数据呈现快速增长的趋势,企业的管理形式也逐渐趋向成熟.对于成长型的企业而言,人力资源管理水平和现状关乎...     

青贮甘蔗尾、青贮玉米秸秆对生长水牛生长性能、消化代谢及血液生化指标的影响

试验旨在研究青贮甘蔗尾(sugarcane tops silage,SS)和青贮玉米秸秆(corn straw silage,CS)对生长水牛生长性能、消化代谢及血液生化指标的影响。试验1:选择21头体重、胎次相同或相近的6月龄生长水牛,随机分为3个组,分别饲喂SS+精料、CS+精料、SS+CS+精料,进行为期30 d饲养试验。试验2:另选6头体重、胎次相同或相近的6月龄生长水牛随机分为2组,分别饲喂SS和CS,不喂精料,利用全收粪法进行为期4 d的消化代谢试验。结果表明:①SS和CS单独饲喂对生长水牛平均干物质采食量(ADMI)影响不显著(P>0.05),饲喂CS组生长水牛平均日增重(ADG)较SS组高,差异不显著(P>0.05)。二者组合饲喂时生长水牛ADMI、ADG比其单独饲喂时高。②CS的养分消化率、氮代谢和能量代谢率均高于SS,但差异均不显著(P>0.05),二者中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)消化率差异不显著(P>0.05)。③SS和CS对生长水牛血液生化指标影响差异均不显著(P>0.05),对动物机体无不良影响。由此可见,单独饲喂时CS养分消化率较SS高,CS及SS对生长水牛血液生化指标均无不良影响,且二者组合饲喂能提高生长水牛生长性能。     

海北高寒草甸地区太阳总辐射、植被反射辐射的有关特征

祁连山海北高寒草甸地区,有较强的太阳总辐射及地表反射辐射.通过2000年观测结果表明,在植物生长期的4～10月,太阳总辐射和地表反辐射总量分别达422.049MJ·m^-2和93.556MJ·m^-2.二者有明显的日变化规律,瞬时最高值出现于北京时间13～14h左右,日瞬时最大值分别可达1200W·m^-2和220W·m^-2以上.植物生长期间太阳总辐射变化受太阳高度角及其当地气候环境的影响,太阳高度角高或气候干燥时太阳总辐射值大,而地表反辅射依太阳总辐射的变化而变化,二者均在月最高,5月次高.植物生长后期,气候湿润,太阳总辐射和地表反射辐射均较低.地表反射率不论在日间还是植物生长的季节间,均表现一"U"型变化过程,其中日间在中午前后最低,最低可达0.19,季节变化以6～月最低,约为0.21,当然受土壤潮湿程度及地表性质等影响,其它时间也可降到0.21.就整个植物生长期内来看,祁连山海北高寒草甸地区地表反射率平均约为0.23.     

西南地区农田主要种植草种及种植模式探讨

利用南方农区丰富的农田资源,大力发展草地畜牧业,引草入田,是发挥草业优势,突破农村发展瓶颈,增加农民收入的一项重要措施。探讨了西南地区农田的主要种植草种以及适宜西南地区的种植利用模式。     

五个饲用玉米品种营养成分研究

试验对5个饲用玉米品种（东陵白、中原单32、科多8号、科青1号、科多4号）不同生育期（拔节期、抽穗期、乳熟期）的主要营养物质变化进行了研究,筛选出适宜当地栽培利用的饲用玉米品种并确定最适刈割期。试验结果表明：随着生育期的推进,各品种中粗蛋白、钙、磷、CA显著下降（P〈0.05）,NDF、ADF、OM含量则显著上升（P〈0.05）,各品种在每个生育期内营养物质含量差异不显著;与其它营养物质不同的是WSC含量在抽穗期显著高于拔节期和乳熟期（P〈0.05）。     

饲料铜水平对生长猪血清铜、血清锌和血清铁的影响

选 60头生长白猪 ( 1 9.2 6± 1 .2 0 kg)随机分成 6组 ,每组公母各半 ,使用硫酸铜作为铜源 ,在饲料中添加不同浓度的铜 ,对照组铜添加浓度为 0 mg/kg,高铜试验各组添加浓度为 1 0 0、1 5 0、2 0 0、2 5 0和 30 0 mg/kg。试验期为 80 d,期间每隔 2 0 d采血一次 ,检测血清铜、血清铁和血清锌的含量。分析结果显示 :高铜饲料可明显提高血清铜含量 ,降低血清锌含量 ,但血清铁无显著性变化。第 2 0 d高铜各组平均血清铜比对照组提高 1 7.7% ( P<0 .0 5 ) ,第 40 d提高 2 0 .2 % ( P<0 .0 5 ) ,第 60 d提高 8.6% ( P>0 .0 5 ) ,第 80 d提高 31 .5 % ( P<0 .0 1 ) ,30 0 mg/kg高铜组与对照组比较差异显著 ( P<0 .0 5 )。血清锌第 2 0 d和 40 d,高铜各组平均比对照组降低 1 1 .6%和 1 0 .3%。