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71.
Forage technology has been successfully introduced into smallholder cattle systems in Cambodia as an alternative feed source to the traditional rice straw and native pastures, improving animal nutrition and reducing labour requirements of feeding cattle. Previous research has highlighted the positive impacts of forage technology including improved growth rates of cattle and household time savings. However, further research is required to understand the drivers, challenges and opportunities of forage technology for smallholder cattle households in Cambodia to facilitate widespread adoption and identify areas for further improvement. A survey of forage-growing households (n = 40) in July–September 2016 examined forage technology adoption experiences, including reasons for forage establishment, use of inputs and labour requirements of forage plot maintenance and use of forages (feeding, fattening, sale of grass or seedlings and silage). Time savings was reported as the main driver of forage adoption with household members spending approximately 1 h per day maintaining forages and feeding it to cattle. Water availability was reported as the main challenge to this activity. A small number of households also reported lack of labour, lack of fencing, competition from natural grasses, cost of irrigation and lack of experience as challenges to forage growing. Cattle fattening and sale of cut forage grass and seedlings was not found to be a widespread activity by interviewed households, with 25 and 10% of households reporting use of forages for these activities, respectively. Currently, opportunities exist for these households to better utilise forages through expansion of forage plots and cattle activities, although assistance is required to support these households in addressing current constraints, particularly availability of water, if the sustainability of this feed technology for smallholder cattle household is to be established in Cambodia.  相似文献   
72.
在(25±1)℃水温、自然光照条件下,设3种投喂方式饲养革胡子鲶(clarias leath-er):第1种连续投喂整个试验期间不间断,第2和3种分别连续投喂3、7 d 后饥饿1 d,3种方式分别以R0(对照组)、R1/3、R1/7表示,试验周期共45 d。结果显示:R0、R1/3和R1/7组胃、后肠和肝脏中蛋白酶活性影响差异不显著,但前肠和中肠内蛋白酶活性影响存在差异(P<0.05)。R0、R1/3、R1/7组的胃、前肠、中肠、后肠和肝脏中淀粉酶影响不显著,R0、R1/3、R1/7的胃、前肠和肝脏内脂肪酶活性影响差异显著(P<0.05),而R0、R1/3、R1/7组中肠和后肠中脂肪酶活性影响差异不显著(P>0.05)。  相似文献   
73.
如果家里有一头老年犬,它一定陪伴你走过了好几个年头,在这么多年里它也许是你的精神寄托;有了它你的生活更快乐了,是它提高了你的生活品质。这个时候,它仍然在你的身旁,但它已经不像年轻时那样爱玩爱闹了,对事情的注意力、警惕性也有明显下降。这些都是不可避免的,你深爱的犬正在逐渐衰老。这个时候,它的需求正在变化,它对你的依赖越来越强,它需要你给它保持一个健康的身体和安逸的老年生沽。  相似文献   
74.
为了从分子生物学角度了解H6N6亚型禽流感病毒在湖南省洞庭湖区的变异特点和进化规律,为该地区H6N6亚型禽流感的防控提供一些理论依据,对2012年在洞庭湖区分离的H6N6亚型禽流感毒株的HA、NA基因进行扩增、克隆和测序,并对所得序列进行同源性和遗传进化分析。结果显示,本试验分离到的5株H6N6亚型禽流感毒株HA裂解位点为PQIETR↓GLF,均没有多个连续的碱性氨基酸插入,属于低致病性病毒;5株病毒的HA和NA潜在的糖基化位点有一些差别,这些差别是否会引起其毒力和致病力上的差异还有待研究;从基因遗传进化关系来看,这些毒株与我国汕头、广西分离的毒株同源性较高。  相似文献   
75.
Proliferation of disease pathogens capable of affecting humans, domestic livestock and wildlife increasingly threatens environmental security and biodiversity. Livestock and wild animals in proximity to human beings are often in the chain of transmission and infection. Globalization of industrial livestock production (especially poultry upon which so much of the burgeoning human population depends) often permits transcontinental disease spread. Rapidly expanding (and often illegal) international trade in wild and domestic animals and their products are increasingly involved in the emergence of new diseases that may have the ability to transmit among humans, livestock and wildlife. Rapidly increasing urbanization has led in many places to overcrowded townships that rely on “bushmeat” for sustenance and has contributed to the emergence of virulent zoonotic pathogens. The emergence and proliferation of pathogens are exacerbated by anthropogenic transformation of natural landscapes in order to increase agricultural and livestock production. This paper posits that data gathered by veterinary ecologists should be interpreted and used by other disciplines. The importance of a thorough knowledge of the “natural history” (ecology) of the disease agent and its human, domestic and wild hosts is stressed.  相似文献   
76.
Research in control of tick-borne diseases and trypanosomosis, and their vectors, namely, ticks and tsetse flies respectively, has been on going for decades. However, very little attention has been paid to the socio-economic factors that are likely to influence the outcome of the interventions in the control of these diseases. Thus, this study was designed to investigate these factors, mainly the intra-household factors influencing decision-making in the control of Vector-borne diseases in the pastoralist areas of Uganda. These factors included: indigenous technical knowledge, household economic factors, and gender. Both qualitative and quantitative methods were used in the collection and analysis of data. The tools used for data collection included among others, participatory learning and action (PLA), and Case studies. The findings included the following: In pastoralist households, a big proportion of the household budget was allocated to vector-borne diseases control. In the male-headed households, men dominated decision-making on vector-borne diseases control, although the goals and priorities of men and women in these households were not the same. Also, vector-borne disease control was predominantly by use of modern veterinary drugs, and pastoralists treated sick cattle by themselves even in situations where there were veterinary personnel.  相似文献   
77.
Three hundred and twenty 1-week old ducklings (160 males and 160 females) were used to evaluate the body weight, body parts and carcass characteristics of the African Muscovy duck. Sexual dimorphism was in favour of the male for all the parameters throughout the experimental period, however the difference was significant (P < 0.05) only after week 2. The 12-week old male weighed 1832.0 ± 180.4 g while the female reached only 68.2% of the male weight. Metatarsus diameter, thoracic perimeter, body length, length of bill, foot and wing in cm were respectively 1.3, 29.5, 57.5, 7.0, 27.1 and 27.8 for the male as compared with 1.2, 25.8, 51.0, 6.3, 23.3 and 26.9 for the female. Body measurements were highly (P < 0.01) correlated with body weight for both sexes, however the highest correlation coefficients were obtained with wing length (0.990 and 0.995) and thoracic perimeter (0.993 and 0.973) for female and male respectively. Live body weight had a linear relationship with both wing length (R2 = 0.991 and 0.81) and thoracic perimeter (R2 = 0.948 and 0.986) for male and female respectively. The female duck yielded higher percent ready-to-cook carcass (66.3%), breast (13.6%), liver (2.8%), heart (1.5%) and gizzard (3.8%) as compared to the male (65.0%, 12.0%, 2.5%, 1.1% and 3.4% respectively) although the difference was not significant (P > 0.05). The male small intestine (185.1 ± 3.4 cm), colon (14.8 ± 1.0 cm) and caecum (17.9 ± 0.4 cm) were significantly (P < 0.05) longer than that of the female (152.2 ± 1.8, 10.8 ± 0.7 and 14.85 ± 0.6 cm respectively).  相似文献   
78.
1. The aim of this study was to describe the role of Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) receptor signalling in chicken.

2. Tissue-specific expression analysis of NOD1, receptor-interacting serine-threonine kinase 2 (RIPK2), nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase 11 (MAPK11 or p38) by quantitative real-time PCR (qRT-PCR) revealed their wide distribution in various organs and tissues.

3. Salmonella pullorum infection activated NOD1 receptor signalling in vivo and in vitro, resulting in significant induction of downstream signalling molecules RIPK2, NF-κB/p65, MAPK11/p38 and the effector molecules IL-1b and IL-8.

4. Activation of NOD1 by its agonist bacterial γ-D-glutamyl-meso-diaminopimelic acid (iE-DAP) in HD11 cells induced the adapter molecular RIPK2 and activated the NF-κB/p65 and MAPK11/p38 pathways, resulting in an increase in IL-8 but not IL-1β. Additionally, inhibition of NOD1 using NOD1-shRNA resulted in downregulation of RIPK2, MAPK11 and IL-8, while NF-κB/p65 and IL-1β were unaltered.

5. These results highlight the important role of NOD1 receptors in eliciting the innate immune response following pathogenic invasion in chicken.  相似文献   

79.
于良  魏刚  王铭  朱鹏  董俊哲 《棉花科学》2021,43(4):66-72
根据近五年实验室检测大数据,分析我国进口巴西棉花品质指标的主体范围,总结不同主体指标各等级分布情况及变化趋势.结果 表明,巴西棉花的品级、长度和马克隆值合同品质符合率高,但不同指标不同时间段品质符合率略有偏差.综合认为:近五年巴西棉花品质一致性好,主体品质占比大,主体指标范围品质符合率高.  相似文献   
80.
丰宁县森林食品资源现状及开发利用前景   总被引:1,自引:0,他引:1  
随着科学技术的进步、人类生活水平的提高,天然绿色食品受到人们的青睐。森林经济植物种源丰富,其可食部分的营养价值及微量元素有的优于栽培植物,开发利用前景广阔。1989年,丰宁林业局同原北京林学院等单位联合,对丰宁森林木本植物资源进行了清查,摸清了种源分布,为合理?..  相似文献   
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