IDF/DeLaval conference on Climate Change, Edinburgh: Don't 'waste' slurry - conference told

By Barry McCann

The first IDF Dairy Summit on climate change was held in Edinburgh, attracting 250 participants from 40 countries worldwide. The issue of reducing the carbon footprint within a growing dairy sector was addressed from a worldwide perspective. A number of dairy farmers gave an insight into their respective dairy industries.

The dairy industry needs to market slurries and by products as organic fertilizers and not categorise them as 'waste', according to Dr John Gilliland, chairman of the Rural Climate Change Forum.

He told the conference that with the world's population growing by 70 million people, a move from starch to protein diets was having an impact on land use and levels of efficiency. He said: "Research is critical to reducing greenhouse gas on the dairy front. More capital also is required, as policy cannot be made without good research.''

On tackling 'efficiency' at farm level, Dr Gilliland said biodigesters could be used for turning methane into energy sources, for consumption on domestic and international markets. However, when questioned about the implications of supplying electricity to a monopoly, he stated that an ideal system would be for farmers to store energy, so it is available at peak times.

Dr. Gideon K Bruckner, deputy director general, World Organisation for Animal Health, said the outbreak of Bluetongue in Western Europe was probably caused by sandstorms in northern Africa. But, he added, climate change was only one aspect of disease spread. The main contributor, he said, was the rise in people travelling worldwide, with zoonotic spores diseases being the greatest threat, transferring from animals to humans.

Scottish government scientific adviser Maggie Gill highlighted the importance of reducing the carbon footprint at farm level and stressed that farmers should act now before governments intervene with legislation.

Torsten Hemme, International Farm Comparison Network, Germany, gave an economic perspective to climate change. "Increasing milk yields from a higher yielding herd can reduce the carbon footprint,'' he claimed.

Milking 40 million cows in China

China has a population of 1.3 billion people with a land mass of 9.6 million k square meter. The country has over 40% of the world's cultivated land and employs over 800 million in agriculture. Well-known for specialising in cotton, wheat, corn and poultry production, Chinese dairying also plays a vital role.

Having 40 million dairy cows producing 28.6 million tonnes of milk annually and processing over 80% into UHT, it is a thriving sector.

Although most dairy farms have between one and three cows, there are intensive units located around the main cities.

One such farm, described at the conference, was located north of Bejing. It has 1,200 cows with 264 hectares of top quality land and a further 790 hectares of forage land. Milk accounts for 70% of the farm output, while 20% of the income is derived from embryos and the remaining 10% from young bulls. Average milk yields are 9,800kg per cow. Fat is less than 4% and protein is about 3.3% to 3.5%. Somatic cell counts are 200,000 while total bacteria are about 50,000.

Recently, there was speculation that the quality of milking from small-scale Chinese holdings was not up to standard as hand milking was a common practice. This saw the introduction of milking villages, which enabled farmers to milk their cows at hygienic centres, while also serving as easy collection points.

Consumers' preferences for milk products are based on the taste, price and a mix of nutritional value and quality. However, a fluctuation in price seldom affects the level of purchase. While the consumption of dairy products in China is small, at 22/kg per person, it is a fast-growing market. With an enormous population, there are threats of world food shortages. The main environmental constraints are access to clean water, utilising energy, a changing climate, pollution, contamination, effects of greenhouse gases while, at the same time, increasing production levels.

2,000 is the magic number in the USA

Agriculture accounts for 8% of the GDP in the USA, using 41% of the land. Large barn-style dairy farms are common as dairy farmer John Nobles, who attended the summit, explained. Farming in upstate New York, his herd grew from 250 cows in 1964 to 1,650 cows today.

Annual milk yields are 10,900/kg per cow, milking three times a day. Over 60% of the feed is homegrown forage, while concentrates are brought in from the mid-west.

One of the measures taken to utilise energy was installing a methane digester on the farm.

The manure from the farm goes through a tube into the methane digester. The methane is converted into electricity and sold to the regional electricity grid. The separated solids are heaped and left to compose.

During the fermentation process, harmful pathogens are killed. At this stage, it is used for bedding cows in the open stalls, reducing the need for extra material on the farm.

The effluent from the slurry is stored in an open lagoon and spread in springtime.

However, there are both environmental and consumer constraints.

The environmental challenge is to conserve energy as it is becoming more expensive.

Technology

The main issue at stake is how far technology can be pushed without a reaction from the consumer.

The USA is spending a lot of money on understanding the emissions from different types of cow housing and diets. California faces the challenge of reducing its greenhouse emissions to 1990 levels by 2020, with the dairy industry being a key player.

On the ideal farm size, John said that the magic number is between 1,500 and 2,000 cows.

He feels this style of farming won't be incorporated worldwide, although it suits their systems.