探花直播 of Cambridge - cattle

Of cabbages and cows: increasing agricultural yields in Africa

lw355 — Mon, 13 Feb 2017 11:17:32 +0000

探花直播humble cabbage, universally despised by British schoolchildren, has found unexpected popularity on another continent. But just as the people of Ghana have developed an appetite 鈥� and a market 鈥� for this leafy green, so too has something else: a virus carried by aphids that causes the cabbages to wilt and die

By contrast, a parasite that emaciates cattle across sub-Saharan Africa has been around for thousands of years but continues to take its toll on certain species of the animals it infects. Prominent ribs are the frequent hallmarks of trypanosomiasis 鈥� caused by the presence of a cunning parasite that evades the animal鈥檚 immune system by periodically changing its protein 鈥榗oat鈥�.

Meanwhile, farmers in Ethiopia are turning away from the traditional zebu cattle towards breeds that produce greater quantities of milk. As a result they are exposing their herds 鈥� and themselves 鈥� to increasing levels of tuberculosis (TB) that are brought about by intensified animal husbandry practices.

What links cabbages and cows are three programmes that hope to connect fundamental research with improving farm yields, and in so doing contribute to solving a looming pan-African problem. More than half of global population growth between now and 2050 is expected to occur in Africa. And more people means a requirement for more food.

Ethiopia, for example, has the largest livestock population in Africa but, with a growing population and increasing urbanisation, even its 53 million cattle are not enough. And now efforts to intensify farming in the country are bringing a significant health concern. 鈥� 探花直播new breeds are more vulnerable than zebu to bovine TB,鈥� explains Professor James Wood from Cambridge鈥檚 Department of Veterinary Medicine. 鈥淭his may have health implications for those who work with and live alongside infected cattle, and also raises concerns about transmission to areas with previously low TB.鈥�

Wood leads a 拢2.9 million research programme, ETHICOBOTS, which is looking at the feasibility of control strategies, including cattle vaccination. 探花直播programme combines partners in eight Ethiopian and UK institutions, and brings together veterinary scientists, epidemiologists, geneticists, immunologists and social scientists. 鈥淲e need this mix because we are not only asking how effective strategies will be, but also whether farmers will accept them, and what the consequences are for prosperity and wellbeing.鈥澛�

探花直播difference that increasing productivity can have on farmers鈥� livelihoods is not lost on an insect expert at the 探花直播 of Ghana, Dr Ken Fening, who is working on another food-related research project. Cabbages are not indigenous to the continent but have become a major cash crop for Ghanaian farmers and an important source of income for traders to markets and hotels.

鈥淎 good crop can bring in money to buy fertilisers and farm equipment, and also help to pay for healthcare and education for the family,鈥� he says. Recently, however, fields of stunted, yellowing, wilting cabbages, their leaves curled and dotted with mould, have become an all too familiar and devastating sight for the farmers of Ghana.

From his field station base in Kpong, Ghana, Fening works closely with smallholder farmers on pest control strategies. Two years ago they started reporting that a new disease was attacking their crops. 鈥淚t seemed to be associated with massive infestations of pink and green aphids,鈥� says Fening, 鈥渁nd from my studies of the way insects interact with many different vegetables, I鈥檓 familiar with the types of damage they can cause.鈥�

Farmers were typically seeing the total loss of their crops and he realised that the devastation couldn鈥檛 just be caused by sap-sucking insects. Despite no previous reports of viral diseases affecting cabbage crops in Ghana, the symptoms suggested a viral pathogen.

With funding through the CAPREx programme, Fening began work with Cambridge plant biologist Dr John Carr. 探花直播pair collected samples of cabbage plants in Ghana showing signs of disease, and also aphids on the diseased plants. Back in Cambridge, Fening used screening techniques including a type of DNA 鈥榝ingerprinting鈥� to identify the aphid species, and sophisticated molecular biology methods to try to identify the offending virus.

鈥淎phids are a common carrier of plant-infecting viruses,鈥� explains Carr, whose research is funded by the Biotechnology and Biological Sciences Research Council as part of the 拢16 million SCPRID (Sustainable Crop Production Research for International Development) initiative. 鈥� 探花直播鈥榰sual suspects鈥� are turnip mosaic virus and cauliflower mosaic virus, which affect cabbages in Europe and the US.鈥�

鈥淲e found that two different species of aphids, pink and green, were generally found on the diseased cabbages,鈥� says Fening. 鈥淚t turned out this was the first record of the green aphid species, Lipaphis erysimi (Kaltenbach), ever being seen in Ghana.鈥� 探花直播pink aphid was identified as Myzus persicae (Sulzer).

What鈥檚 more, the virus was not what Carr expected, and work is now ongoing to identify the culprit. 探花直播sooner it can be characterised, the sooner sustainable crop protection strategies can be developed to prevent further spread of the disease not only in Ghana, but also in other countries in the region.

Another researcher who hopes that eradication strategies will be the outcome of her research project is Dr Theresa Manful. Like Fening, she is a researcher at the 探花直播 of Ghana and a CAPREx fellow. She has been working with Cambridge biochemist Professor Mark Carrington on African animal trypanosomiasis.

探花直播trypanosome that causes the disease is carried by the tsetse fly, which colonises vast swathes of sub-Saharan Africa. 鈥淭his is a major constraint to cattle rearing in Africa,鈥� she explains. 鈥淎lthough trypanosomiasis is also a disease of humans, the number of cases is low, and the more serious concerns about the disease relate to the economic impact on agricultural production.鈥�

Carrington has worked for a quarter of a century on the parasite that causes the disease. He understands how the organism evades the immune system of the animal by changing its coat proteins so as to remain 鈥榠nvisible鈥�.

鈥淲hen you first start working on these parasites you are enamoured with the molecular mechanisms, which we now know a huge amount about,鈥� he says. 鈥淏ut then when you look at the effect on large animals like cows you realise that there is almost nothing known about the dynamics of an infection, and even whether an infection acquired at an early age persists for its lifetime.鈥�

Manful and Carrington set about testing herds in Ghana. They discovered that several trypanosome species can be found in the cattle at one time and that nearly all cattle were infected most of the time.

For Manful, one of the important gains has been the ability to expand the research in Ghana: 鈥淚 now have a fully functional lab and can do DNA extraction and analysis in Ghana 鈥� I don鈥檛 have to bring samples to Cambridge. We are teaching students from five Ghanaian institutions the diagnostic methods.鈥� She and Carrington have been recently funded through a Royal Society Leverhulme Trust Africa Award to continue their work.

鈥淎griculture faces increasing challenges,鈥� adds Carr. 鈥淏ioscience is playing a crucial part in developing ways to mitigate pest impact and reduce the spread of parasites.

鈥淲e want to ensure not only that every harvest is successful, but also that it鈥檚 maximally successful.鈥�

ETHICOBOTS is funded under the Zoonoses and Emerging Livestock Systems (ZELS) programme, a research initiative in the UK jointly funded by six research council and government bodies. Dr Ken Fening and Dr Theresa Manful were funded by the Cambridge-Africa Partnership for Research Excellence (CAPREx) and 探花直播ALBORADA Trust, through the Cambridge-Africa Programme.

Images: top: cabbage aphids (credit: Dr Ken Fening); bottom: cattle in Ghana (credit: Dr Theresa Manful and Professor Mark Carrington).

To keep up to date with the latest stories about Cambridge鈥檚 engagement with Africa, follow #CamAfrica on Twitter.

Africa鈥檚 food requirements, along with its population, are growing fast. Three research聽programmes聽ask how a better understanding of viruses, parasites and the spread of disease can pave the way to improving agricultural yields.

A good crop can bring in money to buy fertilisers and farm equipment, and also help to pay for healthcare and education for the family

Ken Fening

Hendrik Terbeck

Greengrocer at Arusha Market

探花直播text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Sustainable livestock production is possible

gm349 — Wed, 25 Sep 2013 09:10:15 +0000

Consumers are increasingly demanding higher standards for how their meat is sourced, with animal welfare and the impact on the environment factoring in many purchases. Unfortunately, many widely-used livestock production methods are currently unsustainable. However, new research out today from the 探花直播 of Cambridge has identified what may be the future of sustainable livestock production: silvopastoral systems which include shrubs and trees with edible leaves or fruits as well as herbage.

Professor Donald Broom, from the 探花直播 of Cambridge, who led the research said: 鈥淐onsumers are now demanding more sustainable and ethically sourced food, including production without negative impacts on animal welfare, the environment and the livelihood of poor producers. Silvopastoral systems address all of these concerns with the added benefit of increased production in the long term.鈥�

Current cattle production mostly occurs on cleared pastures with only herbaceous plants, such as grasses, grown as food for the cows. 探花直播effects on the local environment include the removal of trees and shrubs as well as the increased use of herbicides, all of which result in a dramatic decrease in biodiversity. Additionally, there is also contamination of soil and waterways by agricultural chemicals as well as carbon costs because of vehicles and artificial fertiliser necessary to maintain the pasture.

探花直播researchers advocate that using a diverse group of edible plants such as that in a silvopastoral landscape promotes healthy soil with better water retention (and less runoff), encourages predators of harmful animals, minimizes greenhouse gas emissions, improves job satisfaction for farm workers, reduces injury and stress in animals, improves welfare and encourages biodiversity using native shrubs and trees.

Additionally, shrubs and trees with edible leaves and shoots, along with pasture plants, produce more food for animals per unit area of land than pasture plants alone. Trees and shrubs have the added benefit of providing shade from hot sun and shelter from rain. It also reduces stress by enabling the animals to hide from perceived danger.

鈥� 探花直播planting as forage plants of both shrubs and trees whose leaves and small branches can be consumed by farmed animals can transform the prospects of obtaining sustainable animal production,鈥� said Professor Broom. 鈥淪uch planting of 鈥榝odder trees鈥� has already been successful in several countries, including the plant Chamaecytisus palmensis which is now widely used for cattle feed in Australia.鈥�

Another success has been in Colombia where a mixed planting of the shrub Leucaena with a common pasture grass resulted in a 27% increase in dry matter for food and 64% increase of protein production.

When ruminants, such as cows, goats and sheep, are consuming the plants from a silvopastoral system, researchers have seen an increase in growth and milk production. Milk production in the tropical silvopastoral system mentioned above was 4.13 kg per cow when compared with 3.5 kg per day on pasture-only systems. As the numbers of animals per hectare was much greater, production of good quality milk per hectare was four to five times greater on the silvopastoral system.

One of the additional benefits of using the silvopastoral system is that it increases biodiversity. Biodiversity is declining across the globe, and the main culprit is farming 鈥� 33% of the total land surface of the world is used for livestock production.聽 If farmers were to switch to sustainable livestock production methods, such as the silvopastoral system, the result would be much greater biodiversity with no increase in land use.

Professor Broom added: 鈥淚t is clear that silvopastoral systems increase biodiversity, improve animal welfare and provide good working conditions while enabling a profitable farming business. 探花直播next step is to get farmers to adopt this proven, sustainable model.鈥�

探花直播paper 鈥楽ustainable, efficient livestock production with high biodiversity and good welfare for animals鈥� was published today, 25 September, in the journal Proceedings of the Royal Society B.

New research advocates use of pastures with shrubs and trees as it is more sustainable, improving animal welfare and increasing biodiversity.

It is clear that silvopastoral systems increase biodiversity, improve animal welfare and provide good working conditions while enabling a profitable farming business.

Professor Donald Broom

Donald Broom

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Farming the 'long-necked thing鈥�: moving from cows to camels

lw355 — Mon, 23 Sep 2013 10:12:38 +0000

It鈥檚 a long and bone-shaking drive from Nairobi to the Marsabit County of northern Kenya.

Marsabit has聽an arid landscape, prone to drought, with dusty lowlands leading up to forested volcanic highlands. 探花直播thousands of people who make a living from the land here 鈥� among them the Boran and Gabra 鈥� are pastoralists. For as long as anyone can remember, they have moved with their livestock, following the rain to find grazing.

In 2012 Dr Elizabeth Watson, a human geographer who specialises in eastern Africa, spent a month carrying out fieldwork in Marsabit. It wasn鈥檛 her first trip to the region: she trained as an anthropologist and an earlier study of the relationship between landscape and ritual had brought her into contact with the Boran and neighbouring groups. She returned last year with a more specific set of objectives: to understand why the Boran people, whose culture has been traditionally tied to cattle herding, are now turning to camel keeping.

She said: 鈥淐amels were by no means unknown to the Boran but they were always considered inferior by people whose daily lives are linked to the cattle which provide them with milk, meat, ritual goods and trading opportunities. Boran identity is so strongly connected to cattle that it is often said that 鈥榯o be Boran is to have cattle鈥�, and some observe a taboo that forbids them from saying the word camel, which they describe as 鈥榯he long-necked thing鈥�.鈥�

Yet, whereas cattle are demanding in terms of their needs for water and fodder, camels have an extraordinary ability to survive for a long time without water and to live on harsh scrub vegetation, and they produce rich, nutritious milk over long periods.

鈥淔aced with increased aridity and pressures of food security, the Boran people began investing in camels as an alternative or addition to cattle around 16 years ago,鈥� said Watson, whose research was funded by a Thesiger Oman International Fellowship and the Royal Geographical Society with IBG.

鈥淎n investigation into how people negotiate such a profound change of lifestyle forms one of the chief strands of my fieldwork. There鈥檚 an assumption that pastoralists, who are seen as being highly traditional, will be resistant to change. In fact they are highly flexible and pragmatic. People spoke to me warmly about the advantages of camels over cattle. And when I asked them how they would pay for brides, they said they would sell a camel to buy cattle so that the ritual would be upheld. It鈥檚 an interesting example of people鈥檚 ability to adapt to changes and embrace opportunities.鈥�

While cattle herding took the Boran on long treks to distant water points in times of drought, camels are happy to live near or in town where they feed on the liquid-rich euphorbia hedges that surround many compounds. 鈥淥ne man said he hadn鈥檛 taken his camel to water for three years. Proximity to town gives herders access to a ready market for milk and they are able to sign contracts with shopkeepers and caf茅 owners,鈥� said Watson. 鈥淲e also found that while the milking of cattle was one of the duties carried out by women, both men and women were involved in milking camels.鈥�

Camels bring new challenges as well as advantages. There are few vets in rural Kenya and camels suffer from a range of diseases, some of which can affect humans. Watson said: 鈥淲hile some people said that their camels were flourishing, others said that their animals had become sick and had died. There was a lack of knowledge and medicines to treat them. Certain breeds of camel are more suited to harsh, rocky areas than others, something not always understood by the development organisations who, seeing the new preference for camels, have started to give them out as a form of restocking.

Watson鈥檚 work will not only inform NGOs but also provide much-needed information about the challenges faced when a society adapts to pressures such as the need for food security.

A move from cattle herding to camel keeping among Kenyan farmers is more than an economic transition, it represents a fundamental shift in age-old customs.

Some observe a taboo that forbids them from saying the word camel, which they describe as 鈥榯he long-necked thing鈥�

Elizabeth Watson

Camel farming

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New strain of MRSA discovered

gm349 — Fri, 03 Jun 2011 09:10:27 +0000

Scientists have identified a new strain of methicillin-resistant Staphylococcus aureus (MRSA) which occurs both in human and dairy cow populations.

探花直播study, led by Dr Mark Holmes at the 探花直播 of Cambridge, identified the new strain in milk from dairy cows while researching mastitis (a bacterial infection which occurs in the cows鈥� udders).

探花直播new strain鈥檚 genetic makeup differs greatly from previous strains, which means that the 鈥榞old standard鈥� molecular tests currently used to identify MRSA - a polymerase chain reaction technique (PCR) and slide agglutination testing - do not detect this new strain. 探花直播research findings are published today in the journal 探花直播Lancet Infectious Diseases.

Dr Laura Garc铆a-脕lvarez, first author of the paper, who discovered the new strain while a PhD student at the 探花直播 of Cambridge鈥檚 Veterinary School, said: 鈥淭o find the same new strain in both humans and cows is certainly worrying. However, pasteurization of milk will prevent any risk of infection via the food chain. Workers on dairy farms may be at higher risk of carrying MRSA, but we do not yet know if this translates into a higher risk of infection. In the wider UK community, less than 1% of individuals carry MRSA 鈥� typically in their noses 鈥� without becoming ill.鈥�

探花直播scientists discovered the antibiotic resistant strain while researching S. aureus, a bacterium known to cause bovine mastitis. Despite the strain being able to grow in the presence of antibiotics, when they attempted to use the standard molecular tests available 鈥� which work by identifying the presence of the gene responsible for methicillin resistance (the mecA gene) - the tests came back negative for MRSA.

When Dr Matt Holden and a research team at the Wellcome Trust Sanger Institute sequenced the entire genome (decoding all of the genes in the bacteria鈥檚 DNA) they realised that the new strain possessed unconventional DNA for MRSA.聽 They found that the new strain does have a mecA gene but with only 60% similarity to the original mecA gene. Unfortunately, this results in molecular tests (which identify MRSA by the presence of the mecA gene) giving a false negative for this strain of MRSA.

Subsequent research revealed that the new strain was also present in humans. During the study, the new strain was found in samples from Scotland, England and Denmark (some from screening tests and others from people with MRSA disease). It has since been identified in Ireland and Germany. Additionally, by testing archived S. aureus samples, the researchers have also identified a recent upward trend in the prevalence of the antibiotic resistant bacteria.

Dr Mark Holmes said: 鈥� 探花直播majority of MRSA testing in British hospitals is performed by seeing if the bacteria will grow in the presence of antibiotics, typically oxacillin and cefoxitin, rather than methicillin - which is now no longer manufactured. This type of testing detects both the new MRSA and conventional MRSA.

鈥淗owever, it is important that any of the MRSA testing that is based on detection of the mecA gene - i.e. PCR based testing, or slide agglutination testing - be upgraded to ensure that the tests detect the new mecA gene found in the new MRSA. We have already been working with public health colleagues in the UK and Denmark to ensure that testing in these countries now detects the new MRSA.鈥�

探花直播new research also raises questions about whether cows could be a reservoir for the new strains of MRSA.

Dr Holmes added: 鈥淎lthough there is circumstantial evidence that dairy cows are providing a reservoir of infection, it is still not known for certain if cows are infecting people, or people are infecting cows. This is one of the many things we will be looking into next.

鈥淎lthough our research suggests that the new MRSA accounts for a small proportion of MRSA 鈥� probably less than 100 isolations per year in the UK, it does appear that the numbers are rising. 探花直播next step will be to explore how prevalent the new strain actually is and to track where it is coming from. If we are ever going to address the problem with MRSA, we need to determine its origins.鈥�

Scientists at the Health Protection Agency (HPA) co-authored this paper, providing the analysis of the human samples of the new strain. Dr Angela Kearns, head of the HPA鈥檚 Staphylococcus Reference Laboratory said: 鈥淭here are numerous strains of MRSA circulating in the UK and the rest of Europe. Even though this new strain is not picked up by the current molecular tests, they do still remain effective for the detection of over 99 per cent of MRSAs. This new strain can be picked up by another type of test, which has shown to be effective in trials in the UK and elsewhere in Europe.

鈥淭his is a very interesting find and the HPA is currently involved in further research to screen a wider population of MRSA samples to ascertain how prevalent it is. It鈥檚 important to remember MRSA is still treatable with a range of antibiotics and the risk of becoming infected with this new strain is very low.鈥�

With funding from the Medical Research Council, the researchers will next be undertaking prevalence surveys in people and in dairy cattle in the UK to determine how much new MRSA is present in these populations. They will also be performing an epidemiological study on farms to identify any factors that may be associated with infection by the new MRSA, to look for further new MRSA strains, and to explore the potential risks of the new strain to farm workers.

Antibiotic resistant bacteria found in both humans and dairy cows.

Although our research suggests that the new MRSA accounts for a small proportion of MRSA 鈥� probably less than 100 isolations per year in the UK, it does appear that the numbers are rising. 探花直播next step will be to explore how prevalent the new strain actually is and to track where it is coming from. If we are ever going to address the problem with MRSA, we need to determine its origins.

Dr Mark Holmes, Department of Veterinary Medicine at the 探花直播 of Cambridge

Royalty-free image Collection by Flickr

Cow

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