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1.
Improved large ruminant productivity is increasingly acknowledged as a pathway for the alleviation of rural poverty and food insecurity in smallholder communities in Southeast Asia; yet, in much of Laos, bovine reproductive management is practically absent. Large ruminant reproduction skills were studied, using face-to-face surveys (n=60) of the knowledge, attitudes, and practices (KAP) of farmers, plus an extension of an examination of parameters of reproductive efficiency (n?=?1786 cattle and 434 buffalo) in the northern provinces of Luang Prabang and Xieng Khouang. The surveys particularly involved female farmers to provide gender-disaggregated data, with females making up 38.3 % of participants. Results confirmed that KAPs of smallholder farmers on bovine reproductive management were low (34–46 %) with trends toward higher KAP scores in male survey respondents. Poor reproductive parameters were identified in both provinces, with low calving percentages of 54–75 and 45–54 % in cattle and buffalo groups, respectively, and prolonged inter-calving intervals of 14.1–19.8 and 26.0 months for the cattle and buffalo groups, respectively. Improving the reproductive efficiency of large ruminants in the northern upland regions would enable smallholder farmers to be more effectively engaged in the dramatic economic growth of the Southeast Asia region, although these findings indicate that intensive training and supportive interventions are required to improve large ruminant reproductive outcomes in communities that have low-level large ruminant husbandry skills.  相似文献   

2.
Livestock provide a wide variety of goods and services that generate income and support the livelihoods of millions of poor people in the developing world. Natural and human selections have shaped existing livestock genotypes throughout the estimated 12,000 year history since the first animal domestication. The result, in many production systems in the developing world, is a livestock genotype adapted to its environment and capable of meeting the needs of smallholder farmers. However, this adaptation is unlikely to be optimal and the rapid changes currently affecting the livestock sector, including policy and market changes, movements of germplasm frequently involving the importation of exotic breeds, and the increasing impacts of climate change are affecting the livestock genotype-environment optimum. This is challenging livestock production systems of smallholder farmers. Current challenges include: high rates of loss of the diversity in livestock populations, rapid transformation in smallholder production systems requiring significant changes in genotypes and their management; increased demand for quality and safe foods; increased market competition in a globalizing economy; increased need for complex partnership arrangements in the ever-changing livestock commodity chain; and lack of adaptive capacity to respond to the rapid system changes. Underlying all these is the general lack of strategies for genetic improvement of livestock in smallholder systems and poor livestock infrastructure in developing countries. Opportunities include increased demand for livestock products — and hence potential market opportunities, and new technologies with potential to leap-frog breeding progress in developing countries. This paper analyses options for pro-poor livestock improvement in developing countries, with particular emphasis on the potential role that science – both old and new – will have, from understanding the social underpinnings to innovative technical solutions. It concludes that one of the highest priority interventions for the smallholder systems is the development of innovative approaches for the strategic use of appropriate genotypes from the available range of global breed resources. The analysis strongly suggests that the highest priority ‘breeding intervention’ should be the provision of appropriate genotypes in a sustainable manner, underpinned by a good understanding of what breed resources exist that have demonstrated potential, where else they could be used, and how they would be delivered to smallholders. Efforts to improve/refine breeding skills of smallholders should proceed in parallel. Institutional arrangements and enabling policies are critical for the success in identifying and applying appropriate genetic technologies, improving access to input services and facilitating access to markets in order to translate productivity gains into incomes.  相似文献   

3.
Commercialization of animal biotechnologies, including those related to reproduction [also known as assisted reproductive techniques (ARTS)], is an increasing reality in developing countries, following the enormous flow of information around us and the increasing global commercial interests in areas where cattle production has its major assets. The present review discusses the achievements of various biotechnological tools for reproduction in cattle including semen handling for artificial insemination (AI), superovulation and embryo transfer (MOET), in vitro handling of oocytes and production of embryos, reproductive cloning and emerging technologies (sex selection, gene targeting and nuclear transfer for livestock transgenesis, genomics for marker-assisted selection, etc.). The application of these technologies for cattle breeding is critically discussed in relation to their impact in the improvement of the efficiency of dairy and beef production in developed and - particularly - in developing countries, which ultimately rule the possibilities of a competitive and sound production of food for human consumption. Despite the remarkable progress made and the punctual importance of some of the above-mentioned technologies, AI remains the most important assisted reproductive technology (ART) in developing countries. Any attempt to gain widespread of any other ART under the predominant economical conditions in developing countries ought to match the simplicity and the success of AI as a breeding tool.  相似文献   

4.
Survey data on dairy cattle production were gathered in two sites [Site I (three-year survey) and Site II (two-year survey)] in Southern Luzon, Philippines. Crossbred (Holstein-Friesian x Sahiwal) dairy cows (n = 122) managed by smallholder farmers belonging to five primary cooperatives under the federation of dairy farmers, were monitored monthly for milk production, feed intake and availability, and reproduction and health status. The purpose of the survey was to identify constraints to productivity. The reproductive status of the cows was monitored by measuring milk and plasma progesterone concentrations by radioimmunoassay and rectal palpation of the ovaries. Plasma concentrations of selected metabolites [beta-hydroxybutyrate (BHB), inorganic phosphorus, albumin, globulin, urea] were also measured at one month before calving and at one month and 2-3 months postpartum, to determine if these could serve as biochemical indicators of nutritional stress. A long calving interval (CI = > 400 days) was identified as the major constraint to productivity of dairy cattle on smallholder farms. The three main problems related to this reproductive constraint were: (1) poor breeding management, in particular lack of accurate estrus detection; (2) repeat breeding, i.e. three or more services were required before conception; and (3) poor ovarian function, shown by some cows with lose progesterone levels. An important cause of these problems was undernutrition, particularly at critical periods of the cow's reproductive life, reflected in the slow recovery from loss in body weight and condition score during the early postpartum period and the increased plasma BHB values at peripartum period in some cows, indicative of negative energy balance, and the flat lactation profile. These findings are useful and relevant as a database in the development of an appropriate management scheme aimed toward improving dairy cattle production and productivity at smallholder level. It highlights the importance of estrus detection, good breeding management and the use of a practical strategic nutritional supplementation, particularly during stressful periods in the cows's reproductive life.  相似文献   

5.
This study was completed to determine the prevalence and distribution of Toxocara vitulorum infection in cattle and buffalo calves and investigate its clinical impact in northern Lao PDR (Peoples Democratic Republic). The results aim to assist decisions on disease control measures that can contribute to increasing cattle and buffalo productivity within smallholder farming systems in tropical areas. A prevalence survey for T. vitulorum in buffalo and cattle calves aged <3 months was conducted between September 2009 and June 2010 in five provinces of northern Lao PDR using a two-stage sampling technique to select 69 villages and 899 calves, with faecal samples collected and examined for T. vitulorum eggs at a local laboratory. At the time of sampling, data on calf morbidity and anthelmintic treatment was also collected. Factors potentially associated with infection and severity of infection were analyzed at univariable and multivariable levels, using T. vitulorum status (positive/negative) and on the positive calves only, faecal egg count levels as outcome variables. The estimated prevalence of T. vitulorum in northern Lao was 22.6 % (95 % confidence interval [CI], 0.17–0.28), and 76.8 % of villages had at least one positive calf. Province was the only significant (p?<?0.05) variable investigated associated with calf infection status. Species (buffalo) was the only variable significantly (p?<?0.05) associated with higher egg per gram of faeces levels among infected calves. Prevalence in calves aged 1–21 days, the reported prepatent period, was 17.5 % (CI 0.11–0.24). Treatment levels were very low (8.2 %) and if treatment occurred it was mostly unsuccessful. The high and wide spread infection of T. vitulorum in cattle and buffalo calves identified in this survey is likely to result in suboptimal cattle and buffalo productivity. Improved management of T. vitulorum infection in cattle and buffalo calves in northern Lao PDR is indicated to reduce potential negative production impacts and enable more efficient development of large ruminant livestock industry as a pathway from rural poverty for smallholder farmers in northern Lao PDR. In addition to quantifying this disease problem in calves, the conduct of this applied participatory research study provided an important opportunity to improve animal health services by increasing the parasite, large ruminant handling and research knowledge and capacity of government animal health staff and farmers.  相似文献   

6.
Toxocara vitulorum infection in large ruminants is endemic in many tropical countries and particularly in South-East Asia. A single treatment of calves with pyrantel at 14–21 days of age effectively controls the parasite. Despite this treatment being readily available, T. vitulorum infection remains common and widespread. To understand drivers of effective control of T. vitulorum infection, we examined treatment practices and knowledge of smallholder farmers of this parasite plus determined annual calf morbidity and mortality and identified potential risk factors for these estimates. Interviews were conducted with 273 smallholder farmers who had calves tested for T. vitulorum 4–6 months earlier. Reproductive rates of 0.6 and 0.4 calf per annum in cattle and buffalo respectively, and annual calf morbidity and mortality of 42.6% (CI 0.38–0.47) and 37.3% (CI 0.33–0.42) respectively, were identified. Interviewed farmers had either none (80.6%) or only minimal (19.4%) knowledge about T. vitulorum and only 2.5% of the farmers treated their calves for T. vitulorum using the recommended control regime. Multivariable logistic regression analyses with random effects showed that the number of adult cattle per household, T. vitulorum infection status of the household herd and farmer knowledge of T. vitulorum were significantly associated with calf morbidity and mortality. Financial analysis using partial budgeting showed a net benefit of USD 3.69, 7.46, 11.09 or 14.86 per calf when treating calves with pyrantel and attributing 25%, 50%, 75% or 100% of morbidity and mortality to T. vitulorum infection. The study identified that poor reproduction, high calf morbidity and mortality combined with very limited farmer knowledge and effective control of endemic Toxocariasis, contribute to suboptimal large ruminant production in mixed smallholder farming systems in South-East Asia. The large net benefit per calf achievable by a single pyrantel treatment should drive implementation of this intervention by smallholder farmers, especially as demand for livestock products continues to increase in this region and forces a change to more production oriented farming. To support this, continued capacity building that ensures knowledge transfer of best practice T. vitulorum control to smallholder farmers is required.  相似文献   

7.
Factors influencing dairy technology adoption and impact on milk yield were studied in 240 smallholder farms in Dejen district, Ethiopia. The majority of the smallholders had more than 20 years of farming experience and were living at more than 10 km distance from market or trading centers (67% and 54% in that order). The dairy technologies studied included the use of crossbred animals, improved feed technologies and improved management practices. Application of acaricides, deworming, vaccination, heat-detection and haymaking had wide application (more than 80% adoption levels) while urea straw treatment, silage making, rotational grazing and fodder beet development were the least practiced ones. Only 20 percent of the cows were crossbred animals. It has been found that higher level of technology adoption is associated with better milk yield regardless of the breed of cattle (local or crossbred) owned by the farmers. Milk yields in local breeds increased by 0.07 times when the number of technologies increased by one unit. In crossbred cows, this rate of increase was five fold higher (0.38 times for one unit increase). Correlation coefficients between and within farm household characteristics and technologies adoption were, generally, significant. Male-headed households adopted significantly higher number of technologies than female-headed households (P?<?0.001). Technology adoption rates increased significantly with increased education level and family size and decreasing distance from market or trade centers (P?<?0.01). The level of technology adoption by smallholder farmers is still unsatisfactory and is highly dependent on gender, family size and level of education of smallholder farmers and location of farms.  相似文献   

8.
An extreme cold exposure event occurred between March 14th and 19th 2011 in northern and central Lao PDR resulting in a major mortality of cattle and buffalo. At least six northern and one central province reported losses, involving 46 districts and 1,384 smallholder farmers, with a total of 7,162 cattle and 3,744 buffalo reported to have died in association with cold weather. Affected animals were observed to shiver, display slow and shallow respiration, lose consciousness and eventually die. Many deaths occurred at night and were recorded in both sexes and all ages of large ruminants. However, mortalities occurred mostly in animals that were free-grazing in the forest and natural grassland, and exposed to the cold weather. Some housed animals that were provided with warmth from shelter and fires and supplementary feed did not die. Samples from dead animals collected for laboratory analysis confirmed that bacterial or viral pathogens were not present. The cause of the mortality was attributed to hypothermia, and the economic losses were estimated at USD 2,463,912.00. Xieng Khouang Province reported the most severe losses with deaths of 4,600 cattle and 1,665 buffalo. At Thong Haihin meteorological station in this province on March 16th and 17th 2011, minimum temperatures recorded were 6.7°C and 7.5°C and rainfall recorded was 36.6 mm and 61.7 mm, respectively. This was the first reported extreme cold event in living memory occurring between the end of dry season and beginning of the wet season in northern Laos. This event is reported in detail as it caused a major loss of wealth for poor smallholder farmers and indicates that strategies to minimise the impact of extreme cold weather events need to be included in livestock development extension programmes.  相似文献   

9.
Bovine venereal campylobacteriosis (BVC) is a major cause of economic loss to the cattle industries in different parts of the world. Camplylobacter fetus subsp. venerealis (Cfv), the main causative agent of BVC, is highly adapted to the genital tract of cattle and is transmitted by carrier bulls. However, infertility and abortions can also be caused by the intestinal pathogens C. fetus subsp. fetus (Cff), and C. jenuni, which are not venereally transmitted. Bovine venereal campylobacteriosis, caused by Cfv associated with lowered fertility, embryo mortality and abortion, repeated returns to service, reduced pregnancy rates and extended calving intervals, has the highest prevalence in developing countries where natural breeding in cattle is widely practised. The epidemiology, pathogenesis and diagnosis of the disease have been the subject of previous reviews. The main focus of this review is to highlight the epidemiology of this disease with particular reference to geographical distribution and recent advances in molecular diagnostic techniques. It is hoped that further research interest of scientists will be stimulated with a view to finding lasting solutions to the reproductive problems associated with the disease for better livestock productivity, particularly in developing endemic countries.  相似文献   

10.
Australian scientists, in partnership with Asian, African and Pacific nations have longstanding interests in applied research on helminth parasite control. Many technologies and practices have been successfully developed to control the parasite problems of smallholder and emerging farmers. This wide range extends from simple herbal remedies to complex, integrated use of chemicals, feeding and breeding. In many cases widespread adoption has been limited by lack of technical support, poor access to input markets and lack of incentives for poorer farmers to seek out and pay for innovations. A further new approach may be required that encompasses the wider production and market environment. The biological, social and economic context of each 'emerging farming system' is different and the matching of technologies to each system requires sound understanding of farmer needs and requirements. Thus, it is essential that farmers, extension workers, and scientists jointly decide what technologies to try, what results mean and, if successful, how to sustain their use. In one Asian example a range of technologies were considered for pig, large ruminant and goat production and parasite control through a participatory process which was also used to agree on what determines sustainability beyond testing. The criteria use to screen technologies and practices were (a) continued availability of inputs including dewormers, (b) dependence on related innovations (e.g. weaning or fencing) and (c) degree of community organisation required (e.g. control of breeding or communal grazing). On this basis deworming with chemicals, especially for Toxacara infection in cattle and buffalo calves following on from supplementary feeding with forages were the most feasible entry points. Further interventions were dependent on changes to the production system, including the introduction of weaning and controlled breeding. Further, the incentives for these production changes could not exist without improved market access and market signals for improved weight and condition. Examples such as this point to the need for stronger multidisciplinary and participatory approaches to parasite control.  相似文献   

11.
The aim of this study was to describe animal production on small farms in the Kaski district of Nepal, with the goal of identifying areas where animal health and productivity could be improved. Eighty-five randomly selected farms from four different Village Development Committees were visited. Farmers were interviewed and premises and animals visually inspected on all farms. Feed samples were collected from a subset of farms. The most commonly kept species were water buffalo (used for milk and meat), cattle (used for milk and labor), and goats (used for meat). Average milk production levels were 4.7?kg/day for water buffalo and 1.9?kg/day for cattle. All animals were milked manually, no calves were weaned, and only one farm practiced artificial insemination. A majority of cattle and goats had access to pasture, and a majority of farms fed their working or producing animals concentrates; however, nutritional input was insufficient in terms of energy, protein, and micronutrient content to increase levels of production. Goat-raising was the most profitable endeavor, followed by water buffalo and cattle. We conclude that animals have the potential to contribute significantly to improved livelihoods of farmers in terms of both income generation and non-tangible benefits. However, we found that significant constraints on animal production exist, including insufficient nutritional levels and a lack of preventative care resulting in animal disease. Furthermore, cultural considerations reflecting attitudes toward cattle shape farming in ways that may limit production. Nevertheless, targeted interventions that improve animal health and productivity are possible without being cost prohibitive.  相似文献   

12.
Structural changes in the economic and demographic landscapes in the developing countries create a host of opportunities for smallholder livestock producers to tap into the economic growth from which they have largely been excluded. However, small livestock herd sizes limit the opportunities available to farmers to commercialize and benefit from the growing demand for livestock and livestock products. Therefore, understanding what it takes to build and maintain the herd size is a critical step in addressing the problem of low market participation. The study used five cross-sectional nationally representative data sets to arrive at the following conclusions. While purchases are a primary source for the initial stock, births are the principal way of increasing the herd size. Livestock deaths as reflected by high mortality rates are the major outflow channel through which livestock leaves the herd, and reducing the mortality rates has a positive effect on the livestock population as evidenced within the cattle sub-sector. Thus, provision of adequate animal health services is key to addressing the high mortality rates which subsequently can lead to increased herd size. As births are the primary means of increasing the herd size, it is necessary to implement interventions that address the reproduction rates. The interventions include adequate feeding of livestock on high-quality feed and strategic feeding to address the dry season challenges. These interventions can facilitate the growth of the young livestock into mature breeding stock and thus increase the herd size.  相似文献   

13.
We conducted a longitudinal study to obtain baseline information about the health and productivity of sows and boars raised by smallholder-pig raisers in the Philippines, and test constraints and opportunities to smallholder-sow production that had been identified previously in a cross-sectional study [More, S.J., Lee, J.-A.L.M., La?ada, E.B., Taveros, A.A., Cotiw-an, B.S., 1999. Weight-for-age of growing pigs raised by smallholder farmers in the Philippines. Prev. Vet. Med. 41, 151-169]. Over 12-18 months, we collected data during monthly on-farm visits about 213 sows raised in 119 herds at 2 sites and 32 boars in 31 herds at 1 site. Sow reproductive performance was low and boars were used only infrequently (an average of 0.9 services/month). Using repeated-measure analyses, we identified sow nutrition and piglet care (such as provision of creep feed and unrestricted access to the sow) as important husbandry issues associated with increased sow productivity.  相似文献   

14.
While there is a general consensus that using dairy technologies, such as improved breeds of dairy cows, can substantially increase farm productivity and income, adoption of such technologies has been generally low in developing countries. The underlying reasons for non-adoption of beneficial technologies in the dairy sector are not fully understood. In this study, we characterised adopters and non-adopters of dairy technologies in Ethiopia and Kenya based on farmers’ resources ownership in order to identify why many farmers in Ethiopia and Kenya have not adopted improved dairy technologies. As compared to non-adopters, farmers who adopt dairy technology own relatively more farm resources. The result signals that differences in resource endowments could lead to divergent technology adoption scenarios. Results show that a higher proportion of sample smallholders in Kenya have adopted dairy technologies than those in Ethiopia. Except for the use of veterinary services, fewer than 10% of sample farmers in Ethiopia have adopted dairy technologies—less than half the number of adopters in Kenya. The higher level of dairy technology adoption in Kenya can be ascribed partly to the long history of dairy development, including improvements in the value chain for the delivery of inputs, services and fluid milk marketing. Interventions that deal with the constraints related to access to farm resources and input and output markets could facilitate uptake of dairy technology in developing countries.  相似文献   

15.
We conducted a cross-sectional study at two sites in the Philippines to obtain baseline information about the reproductive performance of smallholder sows, and to identify important constraints and opportunities for smallholder pig raisers. Using an interview-based questionnaire, we collected data about 99 (with 128 sows) and 123 (144) herds at the northern and southern study sites, respectively. A range of animal- and herd-level measures of sow productivity were assessed, including average interfarrowing interval (9.7 and 6.6 mo in herds at the northern and southern sites, respectively), number of liveborn piglets (8.5 and 8.4) and preweaning mortality (19.0% and 12.8%). We have identified a number of animal- and herd-level factors associated with the productivity of smallholder sows in the Philippines, including aspects of breeding and piglet management and nutrition.  相似文献   

16.
The objective of the study was to investigate constraints to dairy cattle health and production in rural smallholder communities in northern Vietnam, one of the target areas of the Vietnam government's dairy development programme. A total of 99 dairy farms (11 per commune) were recruited from 9 of 32 communes in Ba Vi District, using random two-stage cluster sampling. After the initial questionnaire interviews were conducted, farms were visited at three monthly intervals over a period of 1 year. Information on several health and production parameters relating to the study cattle was collected. Using multiple indicator modelling, it was found that Fasciola infestation, farmers who had been involved in dairying for longer (not indicative of better management skills), larger herd size, and cattle being kept in a shed were linked to reduced reproductive performances.  相似文献   

17.
Status of dairy cow management and fertility in smallholder farms in Malawi   总被引：1，自引：1，他引：0  
A review of the smallholder dairy production in Malawi was conducted using livestock annual reports and other literature that was supplemented with primary data from a baseline survey conducted in December 2009. Smallholder dairy farming in Malawi operates with support from institutions that facilitate access to initial stock and dairy production technologies. Most farmers (94%) keep the animals in pens where feed is provided throughout the year. Results indicated unsatisfactory feeding, housing and health management practices, which negatively impact cow fertility. Dairy population trends suggest low replacement rates, which could be associated to low cow fertility and inadequate management skills. There are challenges related to access to breeding and health services, which further contribute to low productivity. Low fertility is evidenced by low calving rates (22–61%) and long calving interval (405–549 days). Existence of programmes on farmer capacity building provides an opportunity for improved management skills and cow productivity. It is concluded that dairy cow management and fertility have challenges and opportunities that are influenced by the extent to which farmers have access to important services such as extension, health, breeding and finance.  相似文献   

18.
水牛的繁殖受诸多因素的影响。为提高其繁殖力 ,多种繁殖生物技术得到大量研究。水牛精子的稀释、冷冻及人工授精已基本程序化 ,并得到了广泛推广。通过超数排卵和胚胎移植的研究 ,获得了水牛胚胎移植的后代。水牛卵母细胞的采集、体外成熟、体外受精和受精胚的培养也得到大量研究 ,并成功产出体外受精水牛。在水牛胚胎冷冻和移植的研究方面也取得成功并产犊。细胞核移植、基因组和基因图谱等新兴生物技术在水牛上也得到初步研究。随着转基因等生物技术的进一步发展 ,水牛的遗传资源将得到更好的开发  相似文献   

19.
Protein JY‐1 is an oocyte‐specific protein that plays an important regulatory role in the granulosa cell layer and during the early embryo development stages. It is the first specific protein of maternal origin discovered in a single‐ovulating species. In this study, the exon regions of the JY‐1 gene were characterized by sequencing in 20 unrelated cattle (Bos taurus indicus) and 20 unrelated buffaloes (Bubalus bubalis). Eighteen polymorphisms were detected in cattle and 10 polymorphisms in buffaloes. Some of the polymorphisms were identified in codifying regions and caused amino acid changes. The insertion of a thymine was detected in the codifying region of exon 3 of the buffalo sequence when compared to the cattle one. This insertion causes a change in the codons frameshift from this point onwards, modifying the 19 terminal amino acids of the buffalo protein and creating a premature stop codon. This finding may explain reproductive differences between cattle and buffaloes in terms of follicle recruitment, embryo development and incidence of twin pregnancies.  相似文献   

20.
Water buffalo are an ancient component of Turkey’s domestic livestock resources. Commonly referred to as the Anatolian buffalo the animal is part of the Mediterranean group which includes Syrian, Egyptian and Southeast European animals. Once quite numerous, there have been drastic reductions in their numbers since the 1970s due to intensification of dairy activities, agricultural mechanization and changing consumer preferences. The main areas of distribution are in northwest Turkey in the Marmara and Black Sea Regions. Buffalo are kept in small herds by livestock and mixed crop–livestock farmers. Milk is the main product, meat is largely a by-product of the dairy function and provision of the once-important draught power is now a minor output. Buffalo milk is used to prepare a variety of speciality products but output of both milk and meat is very low in comparison to cattle. Conditions of welfare and health status are not optimal. Internal parasites are a constraint on productivity. Some buffalo are being used for conservation grazing in the Black Sea area to maintain optimal conditions for bird life in a nature reserve. Long neglected by government there are recent activities to establish conservation herds, set up in vitro banks and undertake molecular characterization. More effort is needed by government to promote buffalo production and to engage the general public in conservation of their national heritage.  相似文献   

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