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71.
加入世界贸易组织会给我国畜牧业带来一系列的影响 ,在生产方面会削弱我国畜产品生产固有的比较优势 ;在畜产品加工方面除了肉类畜产品深加工的比重低之外 ,我国的肉类加工食品结构也不合理 ;在市场方面则更是面临着外来产品的严重冲击。如何看待入世给我国畜牧产业带来的影响和采取何种应对措施是必须考虑的问题。笔者试图在这些方面进行分析和探讨。  相似文献   
72.
扁穗牛鞭草的抗性与利用途径   总被引:7,自引:0,他引:7  
扁穗牛鞭草是一种优良的草种,不仅具有高产优质牧草的特性,而且对逆境表现出很强的耐性或抗性。在分析其抗旱、抗寒性和耐盐、耐酸、耐金属污染性,以及侵占性、独居性、再生性等特性的基础上,分析了牛鞭草在畜牧业生产、生态治理、污染环境修复等领域的利用潜力。  相似文献   
73.
基于1978—2016年畜禽产品年度产量数据,采用HP滤波技术和非线性MS-AR模型,分析中国畜牧业生产波动的特征,从畜牧业生产区制转换的视角剖析畜牧业生产波动的具体路径,探讨影响畜牧业生产波动和路径转换的原因。结果表明:从生产波动变化趋势上看,猪肉生产增长高峰期出现最早,其次是牛肉、羊肉、禽肉和禽蛋生产,牛奶生产增长高峰期出现时间最晚;从生产波动比较上看,猪肉生产波动幅度最小,其他畜牧产业生产波动幅度相对较大,各畜牧产业生产波动趋势存在差异,但近年来总体趋于收敛。通过模型识别将畜牧业生产划分为低速、中速和快速增长3个区制,低速和中速增长区制下各畜禽业产品产量平均增长率在3%和5%左右,而快速增长区制下平均增长率在10%以上;猪肉生产倾向于保持中速增长,牛肉、羊肉和牛奶生产容易出现低中速增长往复徘徊的现象,禽肉和禽蛋生产在各区制下均较为稳定且区制变迁较为平稳;改革开放以来,除牛奶产业以外,其他畜牧产业生产基本在低速或中速增长区制时间最长。基于此,提出针对不同畜禽产业在不同发展阶段相机制定不同调控政策,推动畜禽产业规模化养殖和产业化经营水平,提高畜禽产业抗冲击能力等建议。  相似文献   
74.
Olive oil pomace (OLP) contains organic matter and nutrients that could be recycled by composting and supplying it to crops, solving the problem of disposal.

The effects of two OLP composts (C1 and C2) were assessed on two leguminous forage crops commonly cropped in the local livestock farms. In particular, C1 was applied on proteic pea and C2 on clover, compared with a mineral fertilizer (Min) and a commercial organic–mineral fertilizer (Org-min). The influence of composts on some soil chemical properties was also investigated.

The application of C1 significantly increased proteic pea dry weight at the end of the cycle by 27.2% and 52.0% and grain yield by 23.2% and 43.6%, in comparison with Org-min and Min, respectively. The clover dry weight during the entire cycle was lower in C2, in comparison with the other treatments, while no significant difference was found between C2 and the Org-min treatment both in yield and plant height.

Soil nitrate decreased from the beginning to the end of the trial in C1 and C2 plots by 22.8% and 50.9%, respectively. Soil phosphorous content significantly increased in Min by 32.4 and 41.7% compared to C1 and C2, respectively. These results showed that the substitution of commercial fertilizers with compost could be an environmentally sustainable solution. The high presence of heavy metals in compost should not affect soil application at least in this short-term trial.  相似文献   
75.
In this study, we examined temporal and spatial dynamics of minerals of forage, soil and cattle serum in two savannas (valley and plain) of South Africa. The aims were to explore the relationships between ecosystem components, and plan communal grazing and fodder flow for sustainable livestock production. In each area, grazing sites near, at intermediate distance from (middle) and far from homesteads were selected. In the valley land, site interacted with season to influence local variations (P<0.05) of soil calcium and microelements. In the plain lands, local variations occurred for soil phosphorus and magnesium. At the large scale, most macro-minerals showed differences between the valley and plain lands. In the valley areas, forage calcium differed (P<0.05) locally in the dry season, whereas in the plain areas, potassium and phosphorus showed local variations (P<0.05) in the wet season. Seasonal variations of most forage elements were significant within each local site of both study areas. All forages were deficient in phosphorus and copper. Cattle serum from the valley area had low iron concentrations. The study concluded that biotic and abiotic factors may influence the distribution of soil and forage elements, but their effects may vary between the two areas. Rangeland improvement and supplementation strategies are suggested to sustain animal production.  相似文献   
76.
Preparations derived from plants were the original therapeutic interventions used by man to control diseases (including parasites), both within humans and livestock. Development of herbal products depended upon local botanical flora with the result that different remedies tended to develop in different parts of the world. Nevertheless, in some instances, the same or related plants were used over wide geographic regions, which also was the result of communication and/or the importation of plant material of high repute. Thus, the Nordic countries have an ancient, rich and diverse history of plant derived anthelmintic medications for human and animal use. Although some of the more commonly used herbal de-wormers were derived from imported plants, or their products, many are from endemic plants or those that thrive in the Scandinavian environment. With the advent of the modern chemotherapeutic era, and the discovery, development and marketing of a seemingly unlimited variety of highly efficacious, safe synthetic chemicals with very wide spectra of activities, herbal remedies virtually disappeared from the consciousness--at least in the Western world. This attitude is now rapidly changing. There is a widespread resurgence in natural product medication, driven by major threats posed by multi-resistant pest, or disease, organisms and the diminishing public perceptions that synthetic chemicals are the panacea to health and disease control. This review attempts to provide a comprehensive account of the depth of historical Nordic information available on herbal de-wormers, with emphasis on livestock and to provide some insights on potentially rewarding areas of "re-discovery" and scientific evaluation in this field.  相似文献   
77.
The social background, farm characteristics, indicators of income and self-evaluation returns of 96 randomly selected users of a Basic Animal Health Service (BAHS) programme in northern Malawi were compared with those of 96 matched past-users and 96 non-users, respectively. All 288 farms were visited between July and October 1997. Data analysis was performed using univariate and multivariate techniques. The results showed that, on average, BAHS users had larger cattle herds (16.3) than part-users (14.7) or non-users (12.4). Similarly, the annual yields of crops were higher for users compared to either of the other groups. Users occupied better houses and owned a larger number of farm and household items than did part-users or non-users. A third of all farmers were engaged in additional income generation to lessen the risk of poverty. However, analysis of the livestock management and the educational background of the farmers suggested that usage of the BAHS programme was not only determined by already existing `wealth'. Improved livestock husbandry and management measures, which do not require capital investment, were more frequently applied by users compared to either of the other groups. Non-users and part-users had attained a lower level of education, were less open towards improved farming methods and felt less knowledgeable than BAHS users. The average straight-line distances from farms using BAHS to their respective village animal health worker (2.2 km) or veterinary assistant (2.9 km) were similar but varied according to ecological zone. Intensified extension and awareness meetings in villages will be required to get more non-users involved in BAHS.  相似文献   
78.
亚硝酸盐中毒(Nitrite poisonig)是畜禽常发生的一种中毒病。用白菜等含硝酸盐较多的菜类作猪的饲料,因调制加工不合理,会产生大量的亚硝酸盐,喂后引起猪急性中毒,常来不急抢救而死亡,对养猪业危害较大。用食用醋精加入调制白菜的浸泡液中,使其pH值为4时,完全可抑制反硝化细菌的活动,基本上不会产生亚硝酸盐。这是因为醋酸是含有2个碳原子的有机酸,对反硝化细菌毒性大,使菌体内DNA和ATP受到破坏,细菌失去脱氮作用所致。用醋精作调制白菜的抑制剂,会起到预防畜禽亚硝盐中毒的作用。  相似文献   
79.
世界农业由子实体向营养体的转型、北方休牧还草政策的出台以及南方理想的自然条件和市场空间,为草畜业发展提供了千载难逢的机遇;南方发展草畜业不失为一条帮助农民快速致富的有效途径;只要破解观念更新、资金筹措、技术传授三大难题,草畜业定能成为南方农业的主要板块。  相似文献   
80.
Two questionnaire surveys (2×44) were conducted among pastoral households, using three grazing management systems. The average number of Tropical Livestock Units (250 kg) was 4.0 per member of the household. Milk production was the most important source of revenue (66% of the total) followed by sale of livestock (17%) and transport (16%). High mortality rates were recorded for all livestock. About 27% of the milk was sold fresh or as butter. Sedentary and transhumant grazing management systems showed similar levels of income, but nomads had a 2.6-fold higher overall net income. The average total gross income from the entire herd amounted to US$ 6382 per household per year. The calculated costs were 29% of the gross returns. The contribution to the total gross revenues of camels, cattle and small ruminants was 58%, 25% and 17%, respectively.  相似文献   
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