Report sifelani chikunya

REPORT TO THE FARMERS CLUB ON MY STUDY VISIT TO CORNELL UNIVERSITY (ITHACA, NEW YORK, USA) by Dr Sife Chikunya Senior Lecturer in Animal Science at Writtle College I recently visited the Department of Animal Science at Cornell University (Ithaca, New York, USA) as one of the recipients of the 2008 Farmers Club Charitable Bursary awards. The aims of my study visit to the USA were to enhance my expertise in advanced laboratory techniques, in particular those used in the analysis of the fatty acids in ruminant (cattle, sheep and goats) food products. The other objectives were to establish international links and professional contacts in this area of research. I also, intended to attend the 2008 Centennial joint annual conference of the American Dairy Science Association and the American Society of Animal Science in order to keep abreast with recent developments and other topical issues in the field of animal science. I also wanted to participate in field visits, to learn and acquaint myself with the livestock industry in the USA. I also intended to learn about the animal science curriculum at Cornell and to identify and acquire learning and teaching resources to support my teaching at Writtle College.

Cornell University is situated in the picturesque small town of Ithaca in New York State, 250 miles North West of New York City. My host at Cornell was Professor Dale E Bauman (Liberty Hyde Bailey Professor) and his group. Professor Bauman is a world renowned scientist in the field of animal science, and the opportunity to work with him was invaluable to my own career development. His main area of interest is the regulation of nutrient use during lactation, growth and pregnancy in ruminants.

The bulk of my visit was spent in his laboratory, learning new lipid analytical techniques.

My interest in the effects of dietary lipids (fats and oils) on the

composition of animal food products (meat, milk and dairy products) and in animal body fluids (blood plasma and semen) stems from the work that I did as post-doctoral fellow at Harper Adams University College before joining Writtle College in 2002.

There are several other current research projects in the Department of Animal Science at Cornell University that are directly relevant to my own research and teaching activities in School of Equine and Animal Science here at Writtle College.

1

There have significant developments in the area of lipid research in the last 10 years.

Consumers, in their food choices, are increasingly aware of the links between types of lipids in diet and their impact on human health. It is recognised that food products from ruminants (cattle, sheep, goats, deer etc) are high in saturated fatty acids, which are viewed negatively from a consumer point of view. The saturation of these fatty acids is a consequence of transformation in the rumen by micro-organisms, of fatty acids consumed by ruminant animals. In recent years, much research emphasis has been placed on studies investigating strategies for modifying the content and composition of these fatty acids, to make ruminant products more acceptable, in line with consumer perceptions and to comply with health recommendations. There have been recent discoveries of fatty acids with the potential to improve human health.

The most noteworthy advancement in this area was the discovery of the potential beneficial health effects of conjugated linoleic acid (CLA). CLA is the collective term to describe several positional and geometric isomers (variants of the same molecule) of linoleic acid, an essential fatty acid. CLA has several potential benefits to human health, such as inhibition of cancer, reducing incidence of obesity, anti-diabetic effects, lowering blood cholesterol, and enhancement of the immune function. The investigation of strategies to enhance the levels of CLA in meat and milk, and its role in regulation milk fat content in dairy animals is a current area of intense of research.

Professor Bauman’s group at Cornell University did some of the pioneering work in this area. I was therefore; greatly privileged to have had the opportunity work his group for six weeks in the summer. I was able to re-acquaint myself with recent developments and knowledge in this area, and also to gain advanced technical expertise in this area.

One of the challenges facing researchers working in this area is the challenge of improving and adapting analytical techniques used in the laboratory in order to accurately extract, characterise and quantify these important fatty acids such as CLA in animal feeds, tissues and in biological fluids such as blood plasma, milk, semen etc. Hence, the greater part of my visit to Cornell University was devoted working in the laboratory learning new analytical techniques in the extraction, separation and quantification of fatty acids. Professor Bauman’s laboratory was an ideal environment to acquire such expertise; they have state of the art equipment and expertise in the area, which I immensely benefited from. I am grateful to Anne O’Donnell, Mahmoud Hassan, Dr Jude Capper and Dr Kevin Harvatine for the assistance they gave me with regards to laboratory work during my visit to Cornell. I also had the opportunity

2

to visit Professor Thomas Brenna’s laboratory in the division of nutritional sciences at Cornell University, where I shown around by Cynthia Tyburczy. She explained and demonstrated the various sophisticated analytical techniques and equipment used in their laboratory. Visiting their laboratory was indeed an eye-opener. Professor Brenna is a distinguished analytical chemist who has published extensively in lipid chemistry. Professor Brenna’s group has developed ground-breaking techniques in the identification, resolution and quantification of the various isomers of CLA. For instance, they developed techniques for elucidating the positions and geometry of double-bonds in the various isomers of CLA. During the study visit I was fortunate enough to fly to Indianapolis (Indiana) to attend the joint centennial meeting of the American Society of Animal Science (ASAS) and the American Dairy Science Association (ADSA).

The meeting was held at the

International Convention Centre in downtown Indianapolis, from 7-11th July. This ASAS and ADSA conference is the largest animal science meeting in the world, with over 3000 delegates. In the meeting, I managed to attend several seminar and poster presentations, including some keynote Centennial lectures. The centennial lectures covered the some of the major achievements, discoveries and challenges facing the livestock industry both in the USA and world wide. Of great significance, in the conference were the challenges posed by global warming to the industry. Several papers on the subject were presented, in particular the effects of using grain and biomass for bio-fuels versus animal feed, and the impact and strategies for mitigating the carbon footprint of the livestock industry. The ASAS and ADSA also covered some of the current challenges relating to teaching animals science courses in American Universities, which I found very informative and relevant to our situation here in the UK. In general, I was overwhelmed by the disparities in resources, between UK and US agricultural institutions. The department of Animal Science at Cornell is well resourced. It has large dairy, beef and sheep units solely devoted for teaching, and for academic and industry research. The university farm is situated near a small town called Dryden, which is about 15 miles from the main campus in Ithaca. I made several visits to the dairy unit to learn about how they conduct and manage their teaching and research operations at the farm. I am grateful to Mr Tom Eddy, Ms Anne O’Donnell for their patience and time showing me around the Research and Teaching Farm. The land on which these units are built is owned by the state of New York. The dairy unit alone is on a 2600-acre site. Ownership of the land by the state

3

has pros and cons, for instance it greatly restricts further development on the site, but on the other hand it reduces overheads associated with the running the operations at the farm. The dairy unit houses 993 Holstein cows and heifers, of which 483 cows are lactating. The average productivity of the cows is 39 kg milk per cow per day, and the average lactation length is 192 days. They operate a three-time daily milking system using a double ten herring bone milking parlour. The bulk of the feeds they use are grown on the estate, corn (maize, 560 acres), alfalfa (Lucerne, 550 acres), grass (Fescue) pastures (200 acres) and wheat (30 acres). The unit is managed such that it breaks even, and generates about US$2,8 million per year in milk sales.

Some of the milk from the dairy unit is sold to the university’s Food Science department where it is processed into ice cream, yoghurts and other dairy products that are sold on campus. The major concern at the unit is dairy cow fertility; they have a culling rate of 30%. They operate an all year round calving system, with 22 to 26 cows calving monthly. The artificial insemination (AI) at the unit is managed and carried by a local commercial AI Cooperative.

The opportunities for student learning, teaching and research at these facilities are second to none. For trial work, The Teaching and Research units charges the department of Animal Science about $1.75 per cow per day to conduct trials at the facility. This is heavily subsidised, the actual cost is about $17 per cow per day.

There are also dormitories on-site at the teaching and research unit for accommodating staff and students during the duration of conducting their research trials; they are only charged a nominal fee of $1 per night. The other facilities for teaching available in addition to the dairy unit are the beef unit (100 cow and calf operation), a sheep unit (1400 sheep, of which 700 are ewes), a swine facility (50 sow, furrow to finish operation) , and a poultry unit (200 birds).

During my study visit to Cornell University I was also able to visit the 75 th Empire Farm Days exhibitions that were held at Seneca Falls (New York) on the 5 th, 6th and 7th of August. The Empire Farm Days is one of the premier farm shows in North America, attracting over 70 000 visitors each year. It was an excellent opportunity to learn about new technologies in the industry, to meet producers and agricultural experts, to familiarise with ground-breaking ideas and innovative equipment.

This was a successful visit. It indeed, enabled me to acquire and widen the range of teaching materials for my lectures at Writtle College at BSc and MSc level. The knowledge, expertise and skills acquired during the visit will no doubt significantly

4

enhance my research skills and range of projects I can offer to support student dissertations and theses at BSc, MSc & PhD levels. I also managed to update myself with recent developments in the field of animal science; this will undoubtedly enhance our teaching the School of Equine and Animal Science at Writtle College. I also managed to establish important professional contacts with various scientists within the livestock industry in the USA. I am sincerely grateful to the Farmers Club Charitable Trust for awarding me the bursary that funded this technical exchange visit to the USA.

5