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101.
试验采用1日龄艾维菌肉仔鸡198只,随机分为6组,每组33只。核黄素添加量分别为0、3.6(1NRC)、7.2(2NRC)、14.4(4NRC)、21.6(6NRC)和28.8mg/kg(8NRC),其中0为对照组,5组为试验组,试验选在夏季高温季节进行(7~8月),试验期间鸡舍温度30—38℃,湿度60%-80%。试验鸡28日龄时,从198只肉仔鸡中每组选出体质量相近的肉仔鸡6只,共6组即36只,用全收粪法进行消化代谢试验,研究高温季节核黄素对日粮营养物质利用率的影响。研究结果表明,高温季节日粮中添加高水平的核黄素,与对照组相比提高肉仔鸡粗蛋白、粗脂肪和粗灰分的利用率。 相似文献
102.
103.
<正>1现有粉碎机的运行状态及分析物料经锤片打击破碎后加速作圆周运动,离心力的作用使物料脱离锤片的打击,并很快在筛片侧形成物料环,粗细物料的质量不同造成物料环的分层,粗料粒层紧靠筛片侧,细料粒层覆在粗料粒层上。如果无法破坏物料的环流层,不但影响大颗粒物料重返粉碎区,而且还影响细物料的过筛, 相似文献
104.
Monde Mapekula Michael Chimonyo Cletos Mapiye Kennedy Dzama 《Tropical animal health and production》2010,42(7):1413-1419
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities.
The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern
Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected
households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l
per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early
lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee
or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had
the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities
of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems. 相似文献
105.
桑蓟马生活习性及防治对策 总被引:3,自引:1,他引:3
桑蓟马(Pseudodendrotrips mori Niwa)俗称举尾虫,属缨翅目(Thysanoptera)、蓟马科(Thripidae)、不完全变态(incomplete metamorphosis)中的渐变态(paurometabola),是我省桑树的主要害虫之一。据调查,全龄使用桑蓟马被害叶与全龄使用正常叶相比,全茧量下降30.0%、茧层量下降37.5%、茧层率下降5.769/6、产卵量下降18.0%、良卵率下降12.0%、孵化率下降8.0%,严重影响蚕农利益及蚕种生产。经多年的调查研究,初步探明了桑蓟马在我场桑园的生活规律及防治对策,现总结于后。 相似文献
106.
Jemberu Dessie Solomon Melaku Firew Tegegne Kurt J. Peters 《Tropical animal health and production》2010,42(5):841-848
The experiment consisting of 7 days of digestibility and 90 days of feeding trial was conducted at Wogda (Ethiopia) to determine
the effect of supplementation of graded levels of concentrate mix (CM) on feed intake, digestibility, and body weight (BW)
change in hay-based feeding of Simada sheep. Twenty-yearling Simada sheep with a mean initial BW of 17.9 ± 0.81 kg (mean ±
SD) were used in randomized complete block design arranged into five blocks of four animals. The four dietary treatments that
consisted of hay alone (T1), hay +150 g dry matter (DM; T2, low), hay +250 g DM (T3, medium), and hay +350 g DM (T4, high)
CM were randomly assigned to each sheep within a block. The CM consisted of wheat bran (WB), noug seed (Guizotia abyssinica) meal and safflower (Carthamus tinctorius) seed meal at the ratio of (2:1:1), respectively. Supplementation with T2 and T3 increased (P < 0.001) total DM and organic matter intake than the control treatment. Overall, supplementation improved (P < 0.001) crude protein intake, digestibility, feed conversion efficiency, BW gain, and profitability compared to the control,
whereas sheep on the high than the low and medium level of supplementation performed better in these parameters among the
supplemented treatments. From the results of this study, T4 is recommended as the best level of supplementation since it resulted
in better nutrient utilization, animal performance, and profitability. 相似文献
107.
Kagira JM Kanyari PN Githigia SM Maingi N Ng'ang'a JC Gachohi JM 《Tropical animal health and production》2012,44(3):657-664
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This
study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from
135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique.
The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also
administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode
eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free
range pigs in Busia District, which can be used when implementing integrated control measures. 相似文献
108.
饲料企业要搞好质量管理工作,首先要重视工作方法的研究。通过这样的研究,选出适合企业的方案,然后贯彻下去,这样,不但能解决企业的质量管理问题,还能推动效率问题的解决,可谓事半功倍。目前,业内的质量管理工作还处于初级阶段,现状与发展的需求不符,加强对饲料企业质量管理工作方法的研究也就很有必要。方向对了路才可能对有效的质量管理工作方法,取决于饲料企业的质量理念。宗旨———增加顾客价值为什么要研究饲料企业质量管理工作方法?有人说是为了“搞好质量管理工作”,也有人说是为了“增加顾客价值”。后者更具高度,若想做百年饲料企… 相似文献
109.
运用测色仪对227个月季种质资源花色表型进行分类,并运用紫外分光光度计测定总类黄酮,探讨二者之间的相关性。结果表明:在a~*和b~*二维象限图上,7类色系主要集中分布在Ⅰ、Ⅱ、Ⅳ象限,在第Ⅲ象限(蓝色)没有分布,花瓣正面颜色分布较为集中、部分橙红色和深红色品种的反面花色分布较为离散;7个色系的明度均为L~(*B)L~(*F),绝大多数色系的颜色参数a~(*F)/b~(*F)/C~(*F)a~(*B)/b~(*B)/C~(*B),并且玫红色、紫红色、橙红色和深红色的正反面花色a~*、b~*、C~*差异显著;各个色系TA之间差异显著(P0.05),深红色TA含量最高。而TF含量,除了深红色和紫红色差异显著外,其他色系之间差异不显著(P0.05);TA与L~*呈负相关关系(P0.01),与花瓣L~(*B)相关性更大;TA与h°负相关(P0.01)。TA与a~*/C~*呈正相关关系(P0.01),与正面颜色参数值相关性更强,而TF与L~*/h°也呈负相关关系(P0.05)。说明TA和TF共同影响花色的呈现,并且花青苷含量的高低是影响花色深浅的主要因素。 相似文献
110.
研究人参三醇组皂苷(PTS)对大鼠坐骨神经急性损伤蛋白表达的影响。建立大鼠坐骨神经挤压损伤模型,随机分为PTS组,模型对照组及空白对照组,每组各10只大鼠;各组均经腹腔注射给药,PTS组损伤后注射PTS;模型对照组,损伤后注射同剂量生理盐水;空白对照组,不损伤坐骨神经,注射同剂量生理盐水。坐骨神经损伤术后30d,免疫荧光化学染色检测PTS对损伤侧坐骨神经神经丝蛋白(NF-M)、微管相关蛋白-2(MAP-2)、生长相关蛋白(GAP-43)表达的影响,观察PTS对损伤侧神经的影响。大鼠损伤侧坐骨神经NF-M、MAP-2、GAP-43平均光密度表达(9.66±0.99、12.43±1.44、0.344±0.040)与模型对照组(8.21±1.25、11.90±1.14、0.278±0.042)比较有极显著性差异(P0.01)。PTS可促进坐骨神经损伤大鼠NF-M,MAP-2,GAP-43的表达。 相似文献